kulim

Kulim Surface Potential Meter

2012-01-27T19:25:00.000-08:00

If there exists a difference in the electrostatic potential between two surfaces and these are put in movement relative to each other there will be a current flowing through an external circuit. This kind of “condensator” was used by Volta and Kelvin to study the differences in Volta potential between various metals. This “condensator” is often also called the Kelvin probe. Yamins and Zisman applied this method to study monomolecular films.1 Since then this method has widely been used for determining the surface potential of monolayers. The design of KSV SPOT is based on these main ideas. The main application area for KSV SPOT is in monolayer studies, but due to its stand-alone property it is also suitable for other areas where surface potential measurements are required.
Insoluble monolayers at the gas/liquid interface are generally characterized by measuring the surface pressure ()- area (A) isotherm. The  - A isotherm is characteristic for any given ampiphile2 or mixtures of ampihphilic molecules. Many substances show a variety of different monolayer phases.3,4 The major phases are easily recognized in the isotherm as sharply separated regimes with different compressibility. Although the measurement of  as a function of A can give valuable information about monolayers (area per molecule, collapse pressure, phase transition pressures and temperatures, mixing behavior of two or more amphiphiles etc) it may not reveal all of the desired information.
A complementary and a more sensitive way to characterize a floating monolayer is to measure the changes in the surface potential, V.5 This is possible due to the fact that an insoluble monolayer at the gas/liquid interface changes the surface potential through this interface. This change equals the Volta potential between the surface of the liquid and that of the metal probe. Normally only the changes in V due to the presence and changes in the state of the monolayer are measured. In this case the clean liquid surface is fixed to the value 0 mV, and the spread monolayer gives the obtained V. V can be used to determine the composition of the monolayer, the dissociation degree of an ionisable monolayer, the orientation and reorientation of the monolayer molecules at the interface during compression.3,5,6,7,8 By measuring V one can also reveal the interaction between the molecules in the monolayer much earlier than by measuring . The type of deposition that has occurred for LB films (X, Y or Z deposition) has also been determined by measuring the V.9

Kulim Surface Potential Meter

2012-01-25T23:23:00.000-08:00

KSV SPOT is a small computer controlled stand alone surface potential measuring instrument. It is based on the non-contact and non-destructive vibrating plate capacitor method. KSV SPOT has a high accuracy, minimal drift and high reproducibility, which guarantee a high sensitivity and stability for the measurements.
KSV SPOT is mainly designed for monolayer measurements, but due to its stand-alone property it is also suitable for surface potential measurements over a range of solids and liquids.
KSV SPOT enables you to complement surface pressure - area data with the more sensitive surface potential data. Thus, giving you for example the following additional information about your Composition, Dissociation degree, Orientation, Interaction, Adsorption of your monolayers

Kulim LB

2012-01-15T21:25:00.000-08:00

Kulim SPR BioNavis

2012-01-15T21:21:00.000-08:00

Measuring Contact Angle,Interfacial Tension And Wettability in Electronics Industry

2011-12-21T23:38:00.000-08:00

Electronics industry provides electrical circuits involving active electrical components. Integrated circuits that are used in electrical and electronic devices are built on wafers made of semiconductor materials. Silicon is the most used semiconducting material. Silicon wafers are made of extremely pure silicon, which requires a high quality control. Polymers are also used in the electronic industry as insulating layers in the fabrication of chips and chip carriers. By using our product brand Attension, Tensiometry can be widely utilized in the electronics industry to characterize different material properties.
Application examples include:

• Cleanliness of silicon wafers and circuit boards is an important factor to ensure the optimized functionality of the final product. Contact angle measurements with optical tensiometers can be used to study cleanliness of silicon wafers and circuit boards during the manufacturing process. • Semiconducting wafers are typically processed with protecting coatings. Quality and uniformity of these coatings can be studied with contact angle measurements. • Wettability and interfacial tension are important characteristics of soldering systems used in electronics industry. The molten solder alloy needs to wet both metal surfaces in order for the surfaces to link. Wettability of molten solder on metal can be defined by contact angle force tensiometer. measurements with

Measuring Contact Angle & Surface Tension In Energy Industry

2011-12-21T23:08:00.000-08:00

Energy industry is a wide term that includes all the industries involved in the production, manufacturing, sales and distribution of energy. It includes petroleum and gas industries, coal industry, nuclear power industry and the renewable power industries. Researchers in the energy industry are developing more efficient and environmentally safe ways to produce energy. The petroleum industry looks for efficient ways of extracting and removing raw material from earth. This requires knowledge on different interfacial interactions between the drilling pipes and crude oil. Our product brand Attension tensiometers provide high precision tools for the demanding needs of different applications of energy industries.
Application examples include:

• Thin film solar cells consist of a photovoltaic coating deposited onto a substrate. Contact angle measurements with optical tensiometer can be used to determine the quality of the coatings.

• Adhesion influences oil recovery in all operations. Therefore studies of adhesion of crude oil to the reservoir rock surface are important. Such adhesion studies can be performed by measuring contact angle using an optical tensiometer.

• Biofouling is an unwanted phenomenon causing contamination in pipelines and heat exchangers which use seawater as a coolant. These kinds of pipelines are commonly used especially next to nuclear power plants. Surface free energy analyzes with optical tensiometer can be used to study the properties of different coatings used to prevent the adhesion of microbial and mineral contaminants to pipelines.

• Surface and interfacial phenomena have a significant role in all stages of petroleum industry. Force and optical tensiometers can be used for example in exploring surface tension of different crude oil compositions to understand oil flow through capillary channels.

Kulim KHT - KSV NIMA Surface Potential Sensor (SPOT)

2011-12-21T19:11:00.000-08:00

KSV NIMA Surface Potential Sensor
The KSV NIMA Surface Potential Sensor is a compact and highly
sensitive characterisation instrument that offers complementary
data on the packing and orientation of Langmuir films. The KSV
NIMA Surface Potential Sensor (SPOT) measures the potential
difference above and below the film.

Applications
The KSV NIMA Surface Potential Sensor allows complementing
data from surface pressure - area isotherm measurements that are
obtained from a Langmuir and Langmuir-Blodgett Trough. It allows
the determination of monolayer composition, molecular orientation,
degree of molecular dissociation and molecular interactions at the
interface. The most common applications are:
· Determining effective dipole moments
The KSV NIMA SPOT can be used to determine effective dipole
moments through simple surface potential measurements of a
compressed film.
· Determining molecular orientation
The KSV NIMA SPOT can be use to obtain information on molecular
orientation by observing changes in surface potential and
combining the data with surface pressure information.
· Film electronic structure characterisation
Even the smallest change in the electronic structure of molecules
can be detected by measuring the change in surface potential.
· Molecular structure characterisation
Quantify the effects of changes to molecular structure through
positional offsets and peak values of the surface potential plots.
· Complex formation monitoring
Observe and follow complex formations between monolayers,
subphase species or adsorbates.

Kulim Electrochemical Setup

2011-12-04T23:43:00.000-08:00

Kulim DPI Farfield

2011-11-28T22:30:00.000-08:00

SPR Kulim

2011-11-28T21:58:00.000-08:00

Kulim KHT-KSV NIMA Brewster Angle Microscopes

2011-11-24T19:43:00.000-08:00

KSV NIMA Brewster Angle Microscopes
Brewster Angle Microscopes enable observation of monolayers, typically at the air-water interface using a Langmuir Trough. They create an image of the surface by detecting changes in the refractive index of the water surface in the presence of surfactant molecules. It provides information on homogeneity, phase behaviour and film morphology.

Applications
A Brewster Angle Microscope (BAM) enables the visualization of Langmuir monolayers or adsorbate films at the air-water interface. In conjunction with a Langmuir Trough, it enables the study of:

· Monolayer/film behaviour

It is possible to observe phase changes, phase separation,
domain size, shape and packing.

· Monolayer/film homogeneity

When combined with a KSV NIMA L & LB Trough, observation can
be performed during compression/expansion at known surface
pressures.

· Influence of subphase conditions on film structures

Observe and study monolayer/film behaviour and formation in
different subphase conditions including salt concentrations, pH
and temperature to name a few (e.g. Gibbs adsorption layers).

· Monitoring of surface reactions

For example, photochemical reactions, polymerisation reactions
as well as enzyme kinetics can be followed in real time.

· Monitoring and detection of surface active materials

For example protein adsorption and nanoparticle flotation.

BAMs are primarily designed for the air-water interface. However under some conditions the KSV NIMA BAM can be used for other interfaces such as air-glass.

Kulim KHT-KSV NIMA PM-IRRAS Polarization Modulation Infrared Reflection Absorption Spectrometer

2011-11-24T01:29:00.000-08:00

KSV NIMA PM-IRRAS Polarization Modulation Infrared Reflection Absorption Spectrometer The KSV NIMA PM-IRRAS is the first infrared spectrometer made specifically for IR analysis of monolayers floating on an aqueous subphase or deposited on reflective substrates. It is a highly sensitive and very surface specific instrument enabling measurements in ambient conditions. The innovative goniometric configuration allows easy angle adjustment and fast setup time.

Applications
PM-IRRAS is a highly surface specific FT-IR method that is capable of detecting chemical compositions from interfacial films down to one molecule thick films. The PM-IRRAS technique allows enhanced detection on substrates and measurements from the air-water interface. Changes in the PM-IRRAS signal intensity and position can be used to infer molecular absorption/desorption behavior and kinetics, molecular packing, phase transitions, hydration, hydrogen bonding and different surface reactions in a thin film. Additionally in PM-IRRAS the properties of the polarized light can be used to determine the molecular orientation in a film.
The reported infrared absorption of the PM-IRRAS is in the range of 800 - 4000 cm-1 making it possible to detect the following: ·

Chemical composition of thin films

Chemical composition can be detected from thin films that are just one molecule thick.

· Adsorption / desorption and surface reactions in mono- and multilayers

Studying interaction of biomolecules using cell membrane models can provide means to understand reactions related to drug delivery and the membrane behavior itself. These kinds of model systems are employed in several application areas, such as drug development, food technology, and biological and biochemical research.

· Phase transitions in thin films

Monolayer phase transitions can be detected with PM-IRRAS. A typical example would be protein denaturation at the interface or deposited layer.

· Hydration / hydrogen bonding

The PM-IRRAS peak position shifts dramatically when the hydration stage changes. This allows the observing of a films structural response due to changing external condition such as pH or temperature.

· Molecular-scale quantitative analysis of molecular orientation

The orientation changes of molecules at the air-water interface or at reflective solids can be detected from the PM-IRRAS peak inten- sity. This enables, for example, observing the effect of Langmuir film packing density as well as Langmuir Blodgett coating orientation

Kulim KHT-Interfacial Shear Rheometer

2011-11-24T01:02:00.001-08:00

KSV NIMA Interfacial Shear Rheometer

The Interfacial Shear Rheometer is a unique instrument that
provides an accurate and quantitative method to measure the
shear properties of fluid interfaces (gas/liquid or liquid/liquid).
The ISR can be combined with a KSV NIMA Langmuir trough,
allowing measurements on both soluble and insoluble films

The relationship between stresses and deformation defines the
rheological properties of a film. Most systems encountered in
industry and in biology are viscoelastic films where these relationships
are nonlinear and intermediate between purely viscous and
purely elastic responses. The rheological properties are extremely
important for defining product stability in different industries such
as food, petrochemical, cosmetics, and pharmaceuticals.
For example protein layers and polymers are strong stabilizers in
dispersion and typically used in the food industry for foams and
emulsions. In the petrochemical industry oil extraction is performed
in multiple steps where oil-water and water-oil emulsions are
formed to recover oil and later on destabilized to separate the two
phases. Many different kinds of emulsifiers, pigments and stabilizers
are widely used in cosmetic and pharmaceutical industries such as
lotions, creams and hair sprays.

· Prediction of emulsion, froth and foam stability.

Viscoelasticity of an interface can predict the stability of a complex fluid. Micelle/droplet fusion and fission are largely dependent on the interface viscoelasticity.

Determination of thin film structure

The presence of networking, hydrogen bonding and other interactions can be detected from the viscoelastic behavior of films.

· Examination of phase transitions

Phase transitions in a monolayer, thin film, can result in a change in the rheological properties of the layer.

· Real time monitoring of surface reactions

Surface gelation, network formation and protein denaturation at interfaces are detected from the changes in the viscoelastic properties.

· Continuous monitoring of molecule adsorption into interfaces

Especially in biological systems the adsorption and desorption at interfaces and surfaces can change viscoelasticity. Many processes in cells such as mitosis are highly dependent on membrane rheology.

Kulim KHT-Farfield Analight Systems for Surface Science and Nanotechnology

2011-11-23T23:29:00.000-08:00

Farfield AnaLight® Systems for Surface Science and Nanotechnology

AnaLight® Systems for Surface Science bring Farfield's revolutionary Dual Polarisation Interferometry (DPI) technology into instrument formats to suit a range of surface science and thin film applications in basic research and industrial product development. The latest product in the range, the AnaLight® 4D adds has capabilities to study birefringence dynamically as these thin films are formed or stimulated range of surface science and thin film applications in basic research and industrial product development. The Workstation provides a flexible temperature range and automated sample introduction for enhanced flexibility and high productivity.

AnaLight® gives surface science, thin film and surface science structural and behavioural measurements in a convenient benchtop package:

Dynamic, high-resolution characterisation of thin films and nanosurfaces revealing interfacial mass and structural changes in real time
Measure film thickness, optical density (RI) and mass loading simultaneously
Data analysis with minimal assumptions and no modelling
Dynamic structural behaviour of polymers, surfactants and biomaterials (soft surfaces)
Quantitative analysis of molecular adsorption, absorption and desorption processes as they happen
Nearfield technique enables study of turbid and scattering systems without compromise

Kulim KHT-Farfield Analight Systems For Biophysics

2011-11-23T22:47:00.000-08:00

Farfield AnaLight® Systems for Biophysics

AnaLight® Systems for Biophysics bring Farfield's revolutionary Dual Polarisation Interferometry (DPI) technology into instrument formats to suit a range of classical biophysics applications in basic research, drug discovery and drug and assay development. The latest product in the range, the AnaLight® 4D Workstation adds a new capability to study Conformation, Kinetics, Affinity and Thermodynamics.

AnaLight® gives biophysical Conformation Activity Relationship measurements in a convenient realtime benchtop package:

Quantitative, real time biomolecule size and fold density measurements
Unique ability to measure affinity and kinetics of both mass and structural changes
Dynamic conformational change measurements as they happen - no mass change necessary
Understand macromolecular assembly and aggregation processes
Study biomolecules in your environment of choice - buffer, DMSO, lipids, detergents etc.

KULIM Force Tensiometer CMC DCA etc....

2011-11-23T00:51:00.000-08:00

kulim Tensiometer / Contact Angle

2011-11-23T00:25:00.000-08:00

Kulim KHT SPR

2011-11-22T19:45:00.000-08:00

Langmuir-Blodgett film characterization in air using surface plasmon resonance

Introduction
The ability to assemble ordered molecular films with tailored
functionality over macroscopic lateral dimensions provides
exciting and unique opportunities in many practical and
commercial applications. Sensors, detectors, displays and
electronic circuit components are just a few examples. This
well known technique is referred to as Langmuir-Blodgett
(LB) deposition, where films of functional molecules,
nanoparticles, nanowires or microparticles are spread at the
air-water interface, compressed and transferred to a solid
substrate. Compared to other organic thin film deposition
techniques, such as thermal evaporation, sputtering,
electrodeposition, molecular beam epitaxy, layer-by-layer
or self-assembly, LB is much less limited by the molecular
structure of the functional molecule. This means that it
is often the only technique that can be used for bottomup
assembly in nanotechnology and functional materials
applications. The aim of this note is to demonstrate that
SPR-Navi is ideal for the ex situ
investigation in air of mono- and multilayer films of stearic
acid deposited on a gold surface.

Experimental
The gold-coated glass slides used in the SPR
measurements were cleaned by immersion in a boiling
1:1:5 NH3OH:H2O2:H2O for ten minutes, flushed thoroughly
with ion exchanged water and blown dry with nitrogen.
Monolayers and multilayers of Cadmium Stearate (SACd,
(C17H35COO)2Cd) were deposited via the LB technique
(KSVNIMA System 2) on cleaned gold slides,

Complete SPR curves were measured after depositing one, three and five layers of
SACd on separate gold slides.

Kulim ASTM D971 Attension Sigma 702ET

2011-11-15T21:49:00.000-08:00

ASTM D971 standard test method for interfacial tension of oil againstwater by the ring method

This application note describes how the Attension Sigma 702ET

can be used to measure interfacial tension of oil against water

according to the ASTM D971 standard.

Description of the standard

This application note describes the measurement of interfacial

tension between oil and water under non- equilibrium conditions

by using the ring method according to the ASTM standard. The

Attension Sigma 702ET allows a precise characterization of wateroil

interfacial tension with this standard. The method is especially

important in petroleum industry as it can be used to determine oil

purity.

In this interfacial tension measurement the platinum ring is lifted

through the water-oil interface. The oil is lying on the water surface

due to the density difference of these two liquids. Water has a

higher surface tension than the oil and therefore force is needed

to detach the ring from the water surface. The force measured is

used to calculate the interfacial tension (mN/m) between oil and

water. The measurement is made within 60 seconds after formation

of the interface with a tensiometer determining tension

between 0-100mN/m. The Sigma 702ET fulfills the requirements

of the ASTM D971 standard. The instrument allows the measurement

do be done fully automatically. A high interfacial tension

value (40mN/m) [1] indicates the absence of undesirable polar

contaminants in the hydrocarbon fluid which means that the fluid

is immiscible with water. A decrease in interfacial tension occurs

for example due to accumulation of contaminants or due to formation

of oxidation by-products. The impurities in the hydrocarbon

fluid encourage the oil to mix with water.

ATTENSION SIGMA 702ET

General applications

The ASTM D971 standard is used to determine the possible

contaminants of hydrocarbon fluids. The purity of hydrocarbon

fluids is important in many industrial areas, such as in aviation,

diesel fuels and transformer oils. For example in aviation, jet fuel

needs to be highly purified as water or dirt contaminations can

cause serious danger in flight safety. Surfactants in jet fuel can

cause the lifting of rust in storage tanks as well as absorption of

water on coalescing surfaces [2]. The ASTM D971 standard is also

a useful indicator of the cetane number of diesel fuels [3]. The

cetane number of diesel fuels is used to define the quality of

combustion during ignition.

QCM-D Kulim

2011-10-31T22:34:00.000-07:00

Real-time Physiological Measurement via A Magnetic AcousticResonance Sensor

Ruifen Hu

Department of Chemical Engineering and Biotechnology, University of Cambridge, UK

Smart polymers have been widely used in biomedical field, since 1950 W. KUHN etc. put forward ‘muscle-like working’ materials. Smart polymers can detect physiological parameters, like pH, ionic strength and blood glucose level, with high sensitivity and selectivity.

In this study, real-time physical detection can be realized by combining smart polymers with a novel acoustic sensor, Magnetic Acoustic Resonance Sensor (MARS). Acoustic resonance is generated in a small quartz disc (12mm in diameter, 0.25mm in thickness), and can be stimulated wirelessly via electromagnetic effect. Measurement can be implemented by implanting the disc coated with a thin layer of smart polymer subcutaneously. pH-sensitive and Glucose-sensitive hydrogels have been investigated. The sensitivities to pH and Glucose can reach 2626.47mV/pH and 2.21mV/mM respectively. The combining system of smart polymers and MARS is a promising tool for implantable biomedical measurement.

QCM-D Kulim

2011-10-31T22:27:00.000-07:00

QCM-D Scientific World Tour 2011

October 19-20 - Beijing, China

Abstracts

The Conformational Behavior of Grafted Polymer Chains at the Solid/Liquid Interface

Investigated Using QCM-D

Guangming Liu

University of Science and Technology of China

The interfacial properties are significantly influenced by the grafted polymers at the solid/liquid interface. However, characterization of the dynamic conformational behavior of the grafted polymer chains is still difficult. Quartz crystal microbalance with dissipation (QCM-D) can be used to study the conformational behavior of grafted polymer chains at the solid/liquid interface.

Generally, frequency shift (Δf) reflects the mass change or the solvation/desolvation of the chains, whereas dissipation shift (ΔD) indicates the structure change or the stretching/collapse of the chains. Based on our studies, I will introduce the application of QCM-D in the study of conformational changes of grafted polymer chains induced by temperature, solvent composition, pH, salt concentration, and salt type. I will also present some results about the grafting kinetics of polymer chains

Kuliim QCM-D

2011-10-10T00:34:00.000-07:00

Take your QCM-D knowledge
to the next level

Sign up for the QCM-D Certificate Training.

Q-Sense's head quarters in Gothenburg, Sweden.
November 28 - December 2, 2011.

The full week of QCM-D training will include hands-on training with different modules such as the humidity module, electrochemistry module and the open module, plus extended QTools data analysis training.

See pictures from previous course.

Please note that there will be a limited number of participants on the course in order to provide you with the best personal service possible.
Please contact Application Specialist Fredrik Andersson for further information or to register.

Get the most out of your QCM-D data using QTools

Join one of the upcoming Q-Sense's QTools training webinars on how to model your QCM-D data.

Upcoming webinars

We have upcoming application webinars on QCM-D and Nanoparticle studies, on the new His.tag Capturing Sensor and QTools introduction.

To register and find more details, go to Q-Sense's Webinar Center

Listen to one of our Application Specialists discuss how to better analyze and quantify your QCM-D measurement data using QTools.

The webinar is an interactive session in which we will walk you through how to analyze raw data using the QTools viscoelastic model. Our Application Specialist will answer your questions during the entire session.

All you need to join are headphones and an internet connection.

Please note, that to provide the best quality we limit the number of attendees in our webinars.

If you would like more information or if you have any questions, please contact us.

Sincerely,
Q-Sense

Tip a friend

info@q-sense.com
www.q -sense.com

If you no longer wish to receive our mailings you can unsubscribe here. Powered by Web Power

Kulim Webinar

2011-10-04T01:13:00.000-07:00

Dear Friends,

It is our pleasure to announce the time table and topics for the next Attension and KSV NIMA webinar and hands-on sessions. For webinars there will be two sessions each day to suit different time zones. The detailed schedule is below. Please note that the times are given in Finnish time (Northern European Summer Time, GMT +3). Each webinar session will last approximately an hour.

WEBINARS

KSV NIMA

Tuesday, October 25^th

Webinar content

· L & LB product range and technology review. This webinar covers the basic offering, measurement methods and applications.

Webinar times

· Session KSV NIMA 1: 10.00 (GMT +3)

· Session KSV NIMA 2: 16.00 (GMT +3)

KSV NIMA

Wednesday, October 26^th

Webinar content

· PM-IRRAS, ISR & BAM product range and technology review. This webinar covers the basic offering, measurement methods and applications.

Webinar times

· Session KSV NIMA 1: 10.00 (GMT +3)

· Session KSV NIMA 2: 16.00 (GMT +3)

ATTENSION

Thursday, October 27^th

Webinar content

· Attension product range and technology review. This webinar covers the basic offering, measurement methods and applications.

Webinar times

· Session Attension 1: 10.00 (GMT +3)

· Session Attension 2: 16.00 (GMT +3)

ATTENSION

Friday, October 28^th

Webinar content

· New application notes regarding;

Ø Interfacial rheology and flotation (including technology presentation related to PD200)

Ø Main application fields of Sigma 702ET

Webinar times

· Session Attension 1: 10.00 (GMT +3)

· Session Attension 2: 16.00 (GMT +3)

HANDS-ON

KSV NIMA

Tuesday & Wednesday, November 8^th -9^th

Training content

· L & LB product range and measurements.

· ISR, MicroBAM and PM-IRRAS

The training topics can be adjusted based on participants whishes.

ATTENSION

Thursday & Friday, November 10^th - 11^th

Training content

· Theta

· Sigma

· BPA

The training topics (e.g. special modules) can be adjusted based on participants whishes.

Please, register to the webinars and hands-on training sessions with information which sessions you want to participate in by email one week prior to the scheduled dates. Registration is done with an e-mail to Maiju.Pykonen@biolinscientific.com or Jaakko.Valimaa@biolinscientific.com. More detailed information on the participation will be sent after registration.

Biolin Webinar

2011-09-23T22:30:00.000-07:00

Webinar on Nanoparticle studies using QCM-D

In this webinar we will review examples where QCM-D has been used to study nanoparticle interactions.

October 12 at 2 PM (China) 3 PM (Korea)

45-60 minutes

Interactive and time for questions

Several examples from literature:

Nanocomposites
Nanoparticles and the environment
Nanotoxicity
Nanomedicine

To register and find more details, go to Q-Sense's Webinar Center

The webinar is an interactive session and our Application Specialist will answer your questions during the entire session and there will be time for questions at the end.

All you need to join are headphones and an internet connection.

Please note, that to provide the best quality we limit the number of attendees in our webinars.

If you would like more information or if you have any questions, please contact us.

Sincerely,
Q-Sense

Register now

Meet Q-Sense at the
QCM-D Scientific World Tour 2011 in Beijing

info@q-sense.com
www.q-sense .com

KULIM Hi-Tech Sdn Bhd

2011-09-14T18:54:00.000-07:00

Association and solubility studies of mixed polyglycol ether surfactants in water

Bassem M. Bajouk, Rolf O. Sköld

Department of Applied Surface Chemistry, Chalmers University of Technology, Kemivägen 10, SE-412 96 Göteborg,Sweden

The effect of varying the molecular structure and the type of counter ion of polyglycol ether based anionic

surfaceactive components on the processes of phase separation, adsorption to the air-water interface and

molecular association in aqueous model metalworking formulations containing a polypropylene glycol was

studied. Phase separation and micellization were studied via static surface tension measurements and by

using an instrument, which enables the automatic scanning of temperature and concentration dependent pH,

turbidity and conductivity data. The anionic surfactants investigated were highly water-soluble and the

surface tension isotherms of all formulations were found to display a common anomalous trend characterized

by an initial maximum in the Gibbs surface excess function followed by a plateau region before a second

maximum occurs just before the concentration taken to indicate micellization. The aqueous mixtures in most

cases displayed concurrent phase separation and micelle formation, which has to be taken into account when

comparing critical micelle concentrations (CMCs). The present availability of parallel data, turbidity data in

particular, allowed incipient phase separation to be detected. This is a circumstance, which would otherwise

pass unnoticed, since it is not visually detectable. Results are considered industrially useful since the control

of the isotropic temperature - concentration space is a key aspect in the design and fine-tuning of

environmentally benevolent aqueous functional fluids for specific applications.

Colloids and Surfaces A: Physicochem. Eng. Aspects 212 (2003) 65 -/77

SPR Navi™ 220A - THE AUTOMATED MP-SPR

2011-09-08T19:50:00.000-07:00

SPR Navi™ 220A - THE AUTOMATED MP-SPR

SPR Navi™ 220A is the top of our line. Choose SPR Navi™ 220A, if you want to perform high-throughput MP-SPR with minimum dead-volumes and increased measurement confidence. As shown in the comparison, it is fully automated. Also here, to fully enjoy the MP-SPR, we recommend the additional set of lasers.

Key Features of SPR Navi™ 220A:

True Goniometric SPR

Unlike most SPR systems, SPR Navi™ 220A is a true goniometric SPR. This eanbles a wide angular scan range ( = 40–78°) that produces a complete SPR curve with absolute angle information. The true goniometric SPR configuration confers great advantages as it widens the range of refractive indexes at which you can measure, allowing you to characterize surfaces in gas and/or liquid. It also allows you to check the quality of user-defined surfaces before sample injection, providing you with additional evidences. In other words, the wide angular scan range makes SPR Navi 200 an extremely sensitive and versatile characterization instrument.

Customizable flow cell

SPR Navi™ 220A comes with dual measurement channels for in-line referencing or duplicate measurements. In addition, the easily accessible flow-cell can be customized for user-specific experiments, thus broadening your experimental capabilities. For instance, BioNavis can provide electrochemical flow cells or flow cells equipped with optical fibers for surface illumination. The flow cell shape can also be customized to tailor the flow dynamics to your needs.

Flexible sensor-slide system

With the SPR Navi™ 220A instrument, you can use the innovative sensor-slide holder for easy “drop-in” placement of your sensor-slide into the instrument. It allows users to change surfaces within seconds, making SPR Navi™ 220A an extremely convenient instrument to work with. The sensor-slide holders can be labeled and used for long-term storage of your custom-modified surfaces. Sensor-slides can be modified outside the instrument, with a great number and combination of layers, prior to the actual analysis. This unique removable sensor system provides additional flexibility. It allows you to combine SPR data with other widely used techniques to provide supporting information, including surface topography, surface wettability, chemical composition, photochemical processes, swelling, adsorption...

Contamination free MP-SPR

The proprietary optical elastomer in the SPR Navi™ 220A finally does away with the need for messy and potentially contaminating index-matching oil. The result is a contamination-free environment for your measurements. The optional immobilizer, a horizontally oriented stand-alone flow cell, can be used for in-situ functionalization of SPR slides. This further minimizes the risk of cross-contamination and enables minimal sample depositions.

Kulim Hi-Tech

2011-08-18T01:13:00.000-07:00

How is contact angle measured?

To measure contact angle using a tensiometer a probe of your solid is brought into contact with a reservoir of the test liquid. The tensiometric method works on the principal that if the forces of interaction, geometry of the solid and surface tension of the liquid are known, the contact angle may be calculated. The user first makes a measurement of the surface tension of the liquid using either a Wilhelmy plate or DuNouy ring. The sample of the solid to be tested is then hung on the balance and tared. The liquid is then raised to contact the solid. When the solid contacts the liquid the change in forces is detected and your Sigma70 registers this elevation as zero depth of immersion. As the solid is pushed into the liquid the forces on the balance are recorded. The forces on the balance are

F_total = wetting force + weight of probe - buoyancy

Your Sigma70 has tared the weight of the probe and can remove the effects of the buoyancy force by extrapolating the graph back to zero depth of immersion. The remaining component force is the wetting force which is defined as:

Wetting force = g_LV P cosq

where g_LV is the liquid surface tension, P is the perimeter of the probe and q is the contact angle. Thus at any depth data is received which can be used to calculate contact angle. This contact angle, which is obtained from data generated as the probe advances into the liquid, is called the ‘advancing contact angle’. The sample is immersed to a set depth and the process is reversed. As the probe retreats from the liquid data collected is used to calculate a ‘receding contact angle’.

KULIM

2011-08-05T22:49:00.000-07:00

Theta optical tensiometer is modular: you can choose exactly the features that you require for your studies. The minimun setup

requires one choice from each of the module categories of camera, sample stage, liquid dispenser and liquid dispenser motion.

Module choices range from camera speeds to manual or motorized movements. Available accessories add measurement types,

control temperature or allow improved measurements.

Attension offers also ready-made Theta packages with pre-selected modules adapted to different needs. For more information

on those packages please contact : KULIM HI-TECH SDN BHD.

QCM-D Scientific World Tour 2011 in Bensheim

2011-07-25T01:32:00.000-07:00

A top scientific meeting on the theme:

QCM-D – A Versatile Tool for Life Science Related Research

September 14-15, 2011

Meet with some of the top surface science researchers and QCM-D researchers at this two days event.

Dr. Ralf Richter will chair this event that takes place in Bensheim in the scientific hot-bed of the Frankfurt area.

Preliminary program

Speakers

Dr. Ralf Richter, CIC BiomaGUNE, San Sebastian (chair) - Biomolecular hydrogels - Combining QCM-D, ellipsometry and imaging techniques for the detailed interrogation of very soft and hydrated surface-confined films
Prof. Henk Busscher, University of Gröningen - Interfacial re-arrangement in initial microbial adhesion to surfaces.
Prof. Tommy Nylander, Lund University - QCM-D to reveal processes at bio-membrane surfaces of relevance for drug delivery
Prof. Pierre Schaaf, CNRS, Strasbourg - From step-by-step construction to one pot film buildup
Dr. Erik Reimhult, BOKU, Institute of Nanobiotechnology, Vienna - Presentation and hydration of biomimetic and non-fouling polymer surfaces
Prof. Christof Wöll, KIT, Karlsruhe – Deposition and loading of metal organic frameworks, MOFs, on solid substrates: A fascinating application field for QCM
Dr. Ilya Reviakine - Hydrodynamic effects in laterally heterogeneous films studied by QCM(-D)

QCM-D, Quartz Crystal Microbalance with Dissipation monitoring, is a versatile tool for studying interfaces at the nanoscale. At this event we will, among other examples, cover:

- Proteins

- Lipids

- Cells and bacteria

- Polymers

Register now

View preliminary program

This is an excellent opportunity for QCM-D users and other surface-scientists.

/Ralf Richter, chair

Welcome to join us at this event,

The Q-Sense team

Tip a friend

info@q-sense.com
www.q-sense .com

Farfield Measuring Conformational Change

2011-07-24T23:11:00.000-07:00

We would like to invite you to join Farfield’s next webinar:

Topic: The Importance of Measuring Conformational Change
Date: Wednesday, August 3, 2011
Time: 2:00 pm, GMT - 9:00 am, EST

Please register at the following link www.farfield.webex.com

If you are not able to attend, just register and we will send you the recorded version.

All the best,

Contact Angle.

2011-07-20T00:17:00.000-07:00

DEMO.

KHT did a Demo in one of our Top Universities.

Theta with KSV software. We got 3hrs to prove.

Surface Plasmon Resonance SPR BioNavis 200

2011-06-28T20:53:00.000-07:00

Dip Coating, LB and LS methods have been shown to be excellentmethods for controlled preparation of thin films graphene and graphene oxide. The methods offer great amount of control for depositing dispersed SG and SGO produced by the liquid exfolia-tion methods. As the liquid exfoliation methods are recognized as some of the most potential methods for producing graphene in industrial scale, these deposition methods are of great impor-tance in graphene research.We introduced more thoroughly two powerful optical methods for characterizing graphene films before and after deposition, PM-IRRAS and SPR. With the KSV PMI 550 it was possible to record detailed IR spectra of floating and deposited layers to determine the chemical composition. The SPR Navi 200 was capable of characterizing the thicknesses and the complex refractive indices of the deposited layers. It was possible to distinguish single sheet and aggregated graphene from each other.

Lb Langmuir Blodgett Film KSVNIMA

2011-06-28T20:36:00.001-07:00

Langmuir Troughs

Langmuir Troughs are used to create, modify and study monolayers at either the gas-liquid or liquid-liquid interface (Langmuir films). A Langmuir film can be defined as an insoluble monolayer of functional molecules, nanoparticles, nanowires or microparticles that reside at the gas-liquid or liquid-liquid interface. The fact that these molecules can move freely at the interface provide great flexibility for the control of the packing density and the study of monolayer behaviour.

Once compressed, a monolayer film can be considered to be a two-dimensional solid film with a surface area to volume ratio far above that of bulk materials. At these conditions, materials often yield fascinating new properties. The Langmuir Trough allows you to infer how particular molecules pack together while confined in two dimensions. The surface pressure-area isotherm can also provide a measure of the average area per molecule and the compressibility of the monolayer.

Potentiostat ACM

2011-06-28T19:40:00.002-07:00

The potentiostatic test is usually performed to determine resistance to pit initiation at a given potential and to simulate galvanic situations using any of Gill AC 8 12 Field Machine and manual potentiostat set to a stable potential whilst recording the current. In the study of pitting the cyclic sweep method can have problems related to sweep rate and too much pitting propagation before sweep reversal. The use of individual samples held at potentials around the suspected pitting potential will allow the correct determination of the pitting potential. For example the graph below shows current versus time for samples polarised at different potentials.

Corrosion Testing and Study

2011-06-28T02:00:00.000-07:00

Cortest was formed in 1977, and since then, Cortest has grown to include a family of related companies providing corrosion testing equipment, corrosion testing services, technical consulting, field service, and training courses.

Cortest Incorporated specializes in a systems approach to meet all of your corrosion testing needs. We manufacture a comprehensive line of corrosion testing apparatus and support equipment that combine to form complete testing capabilities for both static and dynamic test conditions. It is this ability to ensure equipment compatibility and proven system performance which makes Cortest a unique single source of supply for your test equipment needs.

For the past 25 years, Cortest has manufactured laboratory corrosion testing equipment, as listed below. Please select your areas of interest for additional information.

Proof Rings and accessories, for testing of stress corrosion cracking in accordance with NACE Test Standard TM-01-77-90. The Cortest Proof Rings provide an economical but effective way to accurately determine the Stress Corrosion Cracking (SCC) susceptibility of metals in different environments.

Autoclaves for high temperature and high pressure tests at 5,000 psi (350 bars) and 600°F (315°C) (up to 20,000 psi (1400 bars) and 1100°F (600°C) for specific systems).

Slow Strain Rate Test (SSRT) systems with the CERT machines for Constant Extension Rate Tests from 10^-5 to 10^-8 in/sec, including a variety of environmental chambers and controls, and featuring the new CVI (Computer Virtual Instrument).

Corrosion Fatigue Test system extending the capabilities of the CERT machine and simulating a wide range of loading cycles.

Recirculating Test Loop to refresh autoclave systems.

Multiphase Test Loop for studying behavior of materials under multiphase flow conditions.

Training Courses on corrosion, metallurgy, and multiphase flow.

Instrumentation/Sensor Design. Customized instrumentation and sensors for corrosion load, steam, pH, O₂, H₂ and other measurements.

Corrosion Measurement in laboratory equipment.

Custom Equipment for specialized applications. Aside the large range of laboratory equipment available, Cortest has a long experience in customized laboratory equipment. The combination of electrochemical and mechanical testing has been meeting the individual needs of corrosion engineers for all kind of corrosion testing requirements.

QCMD Q-Sense

2011-06-28T01:18:00.000-07:00

Q-Sense Sensor QSX 334 is a representative model surface of native cellulosic fibers, thanks to the native type of cellulose used during coating.

Before use, rinse the sensor gently with water and dry with nitrogen gas. If the sensors are monitored in water, there might be some initial swelling of the cellulose, which will level out.

General cleaning procedures are not given due to the varying usages of this sensor. For some applications like degradation studies, the sensors can only be used once as cellulose surfaces.

Advertisement of SPR Navi 200

2011-06-10T00:37:00.000-07:00

The stand-up poster of Bio Navis product which is SPR Navi 200 is being displayed at one of our Malaysian top universities' souvenir shop to attract potential lecturers or students.

Theta Optical Tensiometer

2011-06-08T03:12:00.000-07:00

Theta Picoliter Dispenser Released

2011-06-07T21:40:00.000-07:00

We are pleased to present the newest addition to the
Attension product line: the Picoliter dispenser! This
additional module to the Theta Optical Tensiometer
allows precision measurements with low volume drops
as small as 20 pl.

Picoliter dispensing is becoming increasingly important
for the study of sorption phenomena in applications
such as inkjet printing and printed electronics. In
addition, the picoliter dispenser enables contact angle measurement of a picodrop deposited on single fiber. A
range of nozzle sizes and heaters exist to accommodate
your needs, and liquid viscosities up to 10 Pas . We
also offer a convex sample holder for improved image
quality as well as a fiber holder for easy picoliter
drop placement on a single fiber or hair.

This module can be included onto any new or
existing Theta Optical Tensiometer, and many
older optical tensiometers.

Contact your closest Attension representative
for further details kulimht@gmail.com

Theta OneAttension Software

2011-06-07T18:27:00.000-07:00

BEST USABILITY & PERFORMANCE WITH ONEATTENSION OneAttension is an all-inclusive software enabling immediate access to the entire range of Attension tensiometry measurements and data analysis with no need to purchase, install and maintain separate software modules. Modern user interface, live analysis, user specific settings, easy data export and software configurability are examples of the functionalities built in for maximal usability and performance. Should you be interested in upgrading your Theta, Theta Lite, CAM 200, CAM 100, CAM 101, Sigma 700 or Sigma 701 tensiometer, please contact your nearest Attension representative. kulimht@gmail.com

THETA PICOLITER DROP DISPENSER

The Theta picoliter drop dispenser enables precision contact angle measurements with low volume drops as small as 20 pl. It allows the study of sorption phenomena in applications such as inkjet printing and printed electronics. In addition, it allows contact angle measurement of a picodrop deposited on single fiber or hair.

THETA NEW PULSATING DROP MODULE FOR RHEOLOGY STUDIES

The PD-200 pulsating drop module for Theta optical tensiometer functions by oscillating drops with control of both frequency and amplitude as well as wave shape (sine, triangle, square, etc.). This enables quick and easy interfacial rheology, providing viscoelasticity information for surfactant applications. Together with OneAttension and an automatic liquid dispenser, the PD-200 enables automatic drop volume adjustement to compensate evaporation. Compared to the previous version, PD-200 no longer requires calibration and benefit from an improved integration to the software.

THETA FULLY AUTOMATIC XYZ SAMPLE STAGE
Attension now offers an automatic XYZ sample stage with improved resolution (0.01 mm). Drop samples can be placed in desired positions to test any location of one substrate enabling fully automatic measurements with oneAttension. When combined with an automated dispenser and motorized vertical liquid dispenser motion, fully software controlled measurements are possible. With OneAttension, it is also possible to program deposition sequences along the X, Y and even Z axis.

ATTENSION WORLWIDE SUPPORT Attension provides high quality support through a network of highly competent distribution partners and from a team of experts based in our offices in Europe, Asia and North America. In Malaysia, Kulim Hi Tech is the official Attension representative and closely work with Attension application specialists and engineers to deliver quality support and services. Attension support can be reach at support@attension.com, through our website support page or with the help of Kulim Hi Tech

In situ investigations on enzymatic degradation of poly

2011-05-31T21:47:00.000-07:00

SPR Bionavis

Q-Sense 4 sample in one Run workhorse

The present study leads to the following conclusion. QCM-D

and SPR can be used to investigate the enzymatic degradation of

a polymer film in real time, where the changes in mass and morphology

of the film can be well described by the frequency and

dissipation in QCM-D as well as the SPR signal response. PCL

with small crystallites degrades in a way of layer-by-layer with

pseudo first-order degradation kinetics. The degradation of PCL

with crystalline lamellae exhibits two-stage kinetics, which relates

to the degradation of amorphous PCL and PCL crystallites,

respectively. The former degrades more quickly than the latter,

leading the film to be microporous

Surface Plasmon Resonance (2 Channels/exchangeable cuvette)

2011-05-25T01:50:00.000-07:00

BB Band played superbly that night ..... Impressed .... Especially Jorma...

Advantages of SPR NAVI 200

• Increased angular range that enables simultaneous gas and liquid-phase measurements

• Contamination-free index matching with a proprietary optical gel

• “Drop-in” sensor plate design• Integrated high-performance liquid handling

• Dual measurement channels for in-line referencing and/or duplicate measurements

• Support for a second laser wave length, for simultaneous determination of RI and thickness

• Automated determination of measurement parameters for sensogram measurement

• High-accuracy sensogram (kinetic) measurements• Easy use of user-defined/modified surfaces

Application notes are provided at our web site: www.bionavis.com

DP Meeting Helsinki

2011-05-25T01:40:00.000-07:00

An Introduction to Biophysical Characterisation

using Dual Polarisation Interferometry

Dual Polarisation Interferometry (DPI) is a highly versatile, powerful analytical technique for

biophysical characterisation of proteins and other biomolecules. It extends the typical dynamic

measurements of conventional biosensors by including an additional quantitative, sub molecular,

conformational measurement.

DPI delivers a unique perspective on biochemistry, linking conformational changes to biochemical activity at a resolution normally associated with ‘big physics.

Two polarisations of light are passed through the

sensor which consists of an upper ‘sensing’ layer

and an embedded ‘reference’ layer. The output

from each of the layers then combine producing two

interference patterns which are detected by a

camera.

As molecules bind (or change shape) on the

surface of the ‘sensing’ layer, they are probed by

the evanescent field from the ‘sensing’ surface.

This, in turn, changes both interference patterns. As

material binds, the interference pattern shifts one

way. As material is removed from the surface, the

interference pattern returns.

The AnaLight® Resolver software automatically analyses both sets of data and outputs the real time

changes in the thickness, density and mass of the molecular layer. All of the calculations are based on

classical optics theory and have been independently validated by, amongst others, the National

Physics Laboratory (NPL) in the UK. www.farfield-group.com

Basics and Applications of the QCM-D Technology

2011-05-24T02:27:00.000-07:00

From Life Science to Polymers -

Basics and Applications of the QCM-D Technology

October 19-20, 2011

During two days you will get the chance to meet with some of the top surface science and QCM-D researchers. Professor Fredrik Höök from Chalmers University of Technology, Sweden, will chair this event.
Invited speakers

Prof. Fredrik Höök, Chalmers University of Technology (chair) – “Design of small-scale sensors guided by QCM-D studies”
Prof. Guangzhao Zhang, South China University of Technology – “QCM-D Studies on Anti-biofouling”
Prof. Jian Ji, Zhejiang University – “Multilayered assemblies as platforms for cardiovascular biomaterials”
Prof. Guangming Liu, University of Science and Technology of China - "The Conformational Behavior of Grafted Polymer Chains at the Solid/Liquid Interface Investigated Using QCM-D".
Dr. Nam-Joon Cho, Stanford University - "Engineering strategies to combat infectious diseases"
Prof. Zhaohui Su, Changchun Institute of Applied Chemistry – “Manipulating Polyelectrolyte Multilayers through Polyelectrolyte Addition”
Prof. Ying Chih Chang, Genomic Research Center, Academia Sinica - "Deposition and Conformations of Surface Tethered Extra-Cellular Matrices Monitored by QCM-D"
Dr. Ping Wang, Shanghai Institute of Applied Physics – “Properties of DNA molecules in the solid-liquid interface using QCM-D applies physics technique"
Prof. Shuqing Wu, South China University of Technology – "Influence of Surface Roughness on Cetyltrimethylammonium Bromide (CTAB) Adsorption from Aqueous Solution"
Dr. Ruifen Hu, University of Cambridge - "Monitoring the viscoelasticity of polymer films on the acoustic sensor"
Prof. Jing-jong Shyue, Research Center for Applied Science, Academia Sinica - "Adsorption of plasmid DNA on the Binary Self-Assembled Monolayers Modified QCM Chip"

QCM-D, Quartz Crystal Microbalance with Dissipation monitoring, is a versatile tool for studying interfaces at the nanoscale. At this event we will cover several life science examples as well as specific polymer topics.

We hope to meet you in Beijing and look forward to listening to the presenting scientists as well as interesting scientific discussions throughout the meeting.

Submit a poster or an oral contribution

"Here you will learn how to make best use of QCM-D results and let them complement alternative surface analysis techniques."

/Professor Fredrik Höök, Chalmers

Welcome to join us at this event,

The Q-Sense team

Tip a friend

info@q-sense.com
www.q-sense .com

LB Minitrough

2011-05-23T02:32:00.000-07:00

Sigma Tensiometer

2011-05-10T08:39:00.000-07:00

Training in Helsinki Office

2011-05-08T01:26:00.001-07:00

DP Meeting

2011-04-27T20:29:00.000-07:00

2011 BiolinScientific and BioNavis Distribution Partner Meeting - Helsinki, Finland

May , 2011

Main Venue: Klaus K Hotel

Bulevardi 2/4 -

Helsinki 00120

Finland

KSV NIMA PM-IRRAS

2011-04-18T01:19:00.000-07:00

Precise methods for thin film surface preparation and characterization are key factors in modern nanotechnology. Polarization modulation infrared reflection adsorption spectroscopy (PM-IRRAS) is a powerful method for measuring FT-IR from molecules on substrates. From the surface specific IR-spectrum obtained with this method it is possible to deduce chemical composition of films, orientation of molecules and relative amount of material on the surface. This is important in many industrial areas utilizing or planning to utilize nanofabrication and self assembly, molecular electronics, coatings, corrosives, sensors and catalysis.

The Langmuir-Blodgett (LB) deposition technique is a way to create one molecule thick films. It offers control over the molecular orientation and film thickness in the molecular scale. Stearic acid (SA) was used as a model compound to present how the KSV NIMA PM-IRRAS can be used to characterize nanofabricated thin films. A self-assembled film of a well known anticorrosive compound for copper containing metals, methylbenzo triazole (MBT), was created on brass and the layer was studied with the KSV NIMA PM-IRRAS.

The KSV NIMA PM-IRRAS is a FT-IR spectrometer mounted on a goniometer and equipped with a photoeslastic modulator. The IR-light is modulated at high frequency (different from the FT-IR source frequency) and at the signal processing the two are separated electronically. The result is that two IR-spectra are obtained simultaneously, a so-called sum spectrum and difference spectrum. Because p- and s-polarized light reflect differently from surfaces, any differences between the two spectra come from surface specific absorptions. Furthermore on conductive surfaces so called mirror effect will enhance p-polarized components and diminish s-polarized of dipoles, which makes it possible to deduce conformational information of molecules from the spectrums [1].

Also the use of sum and difference spectra diminishes environmental effects on the spectra, such as CO2 and water vapor, and removes the need for protective gasses in reflection measurements. This property allows the to have a very open architecture, enabling measurements from liquid surfaces and solid samples of almost any size. The open design also allows combined use of external UV light source, heater or other complementary equipment.

Conclusions

The PM-IRRAS method was found to be excellent for FT-IR experiments of nanometer scale thin films. It was possible to acquire FT-IR spectrums of films of around 2 nm thick, and also deduce molecular orientation from the experiments. Linear correlation between LB layer number and peak intensities was found. This demonstrates that the KSV NIMA PM-IRRAS is a powerful tool for thin film characterization and analysis. The measurements are fast and simple to perform thanks to KSV NIMA PM-IRRAS unique design.

This application note illustrates how the KSV NIMA Interfacial Shear Rheometer can be used to measure viscoelastic properties of Langmuir films and mo

2011-04-08T02:30:00.000-07:00

Introduction

Rheology is a branch of science studying the flow of materials. Interfacial rheology concerns the unique two dimensional systems formed between two immiscible phases like liquid and gas or liquid and liquid. The stability of interface depends a lot on the viscoelastic properties of the interface, which makes it a crucial aspect for many industries where foams, emulsions and dispersions are used such as in pharmaceuticals, foods, beverages, cosmetics and coatings.

Interfacial rheology is a challenging field of research because the magnitude of forces in the interface is really small. Rotating ring and bicone methods have been developed, but they have been demonstrated to work only with macromolecular compounds at the interfaces. The KSV NIMA Interfacial Shear Rheometer (ISR) utilizes a small magnetic probe which is moved with an oscillating magnetic field. The method reduces the inertia and enhances the sensitivity of the probe compared to the rotating ring method and makes it possible to measure low molecular weight surface active compounds.

In dynamic rheological experiments three variables are measured: applied stress (σ), strain (γ) and phase shift (δ) between the stress and strain oscillation. Dynamic viscoelastic modulus G* is obtained as a function of oscillation frequency from the measurement, and it can be separated into two components, elastic (or storage) modulus G’ and viscous (or loss) modulus G’’.

This application note illustrates how the KSV NIMA Interfacial Shear Rheometer can be used to measure viscoelastic properties of Langmuir films and monolayers.

Materials and methods

A Langmuir monolayer of 1-eicosanol was created by spreading 80μL of a 1mg/ml chloroform solution onto a distilled water surface using a KSV NIMA ISR Langmuir Trough. An ultra-light glass capillary ISR probe was used in the measurements, and a strain of 30 μm (approximately 3%) was used in all the experiments.

Two different types of experiments were performed. Dynamic single frequency experiments as a function of surface pressure were performed with an oscillation frequency of 0.2 Hz. Frequency sweep experiments as a function of oscillation frequency were performed from two different surface pressures, 5 mN/m and 30 mN/m.

Conclusions

The KSV NIMA Interfacial Shear Rheometer shows excellent sensitivity, making it capable to measure viscoelastic properties of Langmuir films and monolayers. It extends the interfacial rheology measurements from not only studying self absorption of macromolecules but also to study Langmuir monolayers of surface active compounds. This makes it possible to study viscoelastic properties of emulgators that are not polymeric. The precise control of surface pressure during the measurement makes it also capable to model natural systems like cell membranes enabling viscoelastic change measurements at the membrane level.

Q-Tools Webinar playback

2011-04-04T01:35:00.000-07:00

https://q-senseab.webex.com/q-senseab/k2/playback.php?FileName=http%3A%2F%2Fwww.q-sense.com%2Fsauerbrey-tutorial.wrf&rnd=0.8485829113051295&isUTF8=1

Remembering 2010 Iceland Volcanic Ash

2011-03-31T02:11:00.000-07:00

DATE FRIDAY 16, 2010. TIME 16 HOURS

START FROM GOTHENBURG SWEDEN TO LONDON UK.

ENTERING DENMARK

ENTERING GERMANY

ENTERING NETHER LAND

ENTERING BELGIUM

ENTERING FRANCE- DIRECT TO Z1 DU PORT DUNKERQUE

ENTERING UK- DOVER PORT TO DOVER TRAIN STATION

REACH ST. PANCRAS INTERNATIONAL ON SATURDAY 17. 2010 8.30 HOURS. 1600KM

l AM BEING HOLD BY BRITISH M16 OUTSIDE ST. PANCRAS INTL TRAIN STATION

SUSPECTED ME AS TERRORIST, BUT THEN THEY LET ME GO SINCE I GOT NOTHING ON ME . MEET ENGLAND PM GORDON BROWN OUT SIDE THE TRAIN STATION.

PM IS ON HIS ELECTION CAMPAIGN VISITING PUBLIC AT THE TRAIN STATION.

ALL BECAUSE OF VOLCANIC ASH FROM ICELAND.

SPR Navi 200 specification

2011-03-26T01:49:00.000-07:00

SPR Navi 200 specification

1. True goniometric principle, enabling to record the full SPR curve for thickness and refractive index model-ing

2. Wide SPR angle range (40 degrees to 78 degrees) allowing to measure both liquid and gas samples with the same instrument

3. Proprietary SPR slide holder allowing easy change and use of SPR gold slides

4. Easy drop-in action in placing the SPR slide in the instrument

5. Easily removable and easily customizable flow cell

6. Modular design allowing to add an autosampler and other features, such as multi wavelength function, at the later stage

7. No need to use messy and inconvenient index matching oil because of the proprietary index matching gel

8. Open design allowing the customer use their own fluidics and flow control (our pump can easily be by-passed)

9. Build in peristaltic pump and optional syringe pump available

10. Easy to use slide holder allowing quick and easy slide replacement without any tools

11. External immobilizer allowing the instrument be used while immobilizing the gold surfaces

12. Possibility to use two lasers with different wave lengths and/or even IR lasers

13. Optional electrochemistry flow cell

Contact Angle: Theory

2011-03-24T04:12:00.000-07:00

Contact Angle: Theory

The following is a short introduction to the concepts involved in the measurement of contact angles. Included is an introduction to the techniques involved and some practical advise. For those interested in further information a list of references appears at the end of this chapter.

What is contact angle?
Contact angle ,q, is a quantitative measure of the wetting of a solid by a liquid. It is defined geometrically as the angle formed by a liquid at the three phase boundary where a liquid, gas and solid intersect.

It can be seen from this figure that low values of q indicate that the liquid spreads, or wets well , while high values indicate poor wetting. If the angle

q is less than 90 the liquid is said to wet the solid. If it is greater than 90 it

is said to be non-wetting. A zero contact angle represents complete wetting.

recent history of the interaction. When the drop has recently expanded the angle is said to represent the ‘advanced’ contact angle. When the drop has recently contracted the angle is said to represent the ‘receded’ contact angle. These angles fall within a range with advanced angles approaching a maximum value and receded angles approaching a minimum value.

The difference between the maximum(advanced) and minimum(receded) contact angle values is called the contact angle Hysteresis. A great deal of research has gone into analysis of the significance of hysteresis. It has been used to help characterize surface heterogeneity, roughness and mobility. You are recommended to the papers listed in the reference of this section for details on experiments regarding hysteresis.

Contact angle can also be considered in terms of the thermodynamics of the materials involved. This analysis involves the interfacial free energies between the three phases and is given by:

g_lv cos q = g_sv- g_sl

where g_lv,g_svand g_sl refer to the interfacial energies of the liquid/vapor, solid/vapor and solid/liquid interfaces.

Coatings: Coatings may be applied to any solid for testing contact angles. Microscope slides and cover slips make ideal supports for such an application. Ideally the coating should be applied to all sides. If you reduce the size of your sample by cutting after coating you will expose part of the support which is not coated. This will introduce an error in your data especially if the cut side is rough. Your data may be consistent enough to compare between similarly treated samples but the absolute values will not be accurate.

Testimonials

2011-03-22T11:02:00.000-07:00

CNRS Nancy University, France

Founded in 1939, the Centre National de la Recherche Scientifique (National Center for Scientific Research) is a government-funded research organization that account for more than a quarter of the public research in France. Geographically, the CNRS is divided in 19 regional centers, with the Nancy campus being part of one of them.

“We are using KSV NIMA PM-IRRAS instrument to record IR spectra on various monolayers formed at air-water interfaces and often used as model of biological membranes. Our studies aim for instance at characterizing the interaction of drugs or toxics with the monolayers. We use KSV NIMA Langmuir troughs to form monolayers and control packing densities. Our relationship with KSV NIMA is very special: they always give very fast answers and they are interested in helping us with our research. For instance, their PM-IRRAS was created after we expressed our interest toward such a system and following discussions between our research team and KSV NIMA. We had been using another IR system previously, spending a lot of time adjusting the system and playing with mirrors. The ease of use and fast setup of the KSV NIMA PM-IRRAS has greatly simplified our work. This unique configuration of the instrument is benefiting our research on floating monolayers.”

The adsorption and network formation of proteins to air-liquid and liquid-liquid

2011-03-22T10:55:00.000-07:00

Introduction
The adsorption and network formation of proteins to air-liquid and liquid-liquid interfaces is a commercially important process in food, cosmetics and pharmaceutical industries. Especially in food industries where natural components of food fats, oils, proteins and water usually form colloidal solutions and the colloidal structure is partially stabilized by amphiphilic proteins. In some cases the proteins can form a two dimensional network at the interface while denaturating, increasing the stability of the emulsion or dispersion dramatically. This effect, also called interfacial gelation, can be easily detected from the viscoelastic properties of the interface, but the phenomena has not been extensively investigated yet due to the lack of sensitive enough methods to perform rheological experiments on interfaces.
The KSV NIMA Interfacial Shear Rheometer (ISR) uses a floating magnetic probe to detect the viscoelasticity of the interface. The method is highly sensitive because the probe inertia is small compared to the measured changes, and the method has been proven suitable for many different viscoelastic interfaces. [1-5]
Dynamic shear rheological experiments are capable of separating the storage (elastic) and loss (viscous) modulus of complex rheological behavior. When time dependent network formation is measured, it is possible to measure the changes of the viscoelastic components quantitatively. It is also possible to determine the gel point of the system after which the elastic properties start to dominate over viscosity and a two dimensional gel has been formed at the interface.
This application note demonstrates how the KSV NIMA Interfacial Shear Rheometer can be used to study monolayer viscoelastic properties at the air-water and oil-water interface.
KSV NIMA AN 4
Materials and methods
A 20 mg/ml solution of Lysozyme (hen egg, Sigma Aldrich) was prepared in PBS buffer. Two distinct measurements were conducted, one at the air-water interface, the other at the oil-water interface. For the air-water (AW) interface measurement, a low volume measurement cell was filled with PBS buffer. In the oil-water (OW) interface experiments Brassica rapa oil was carefully poured on the buffer phase, which was otherwise prepared the same way as for the AW experiments. For both experiments, after a short background measurement the Lysozyme solution was injected to the buffer phase so that the final concentration of the lysozyme compared to buffer was 1 mg/ml. The ISR measurements were performed in a single frequency mode using a frequency of 0.1 Hz and shear of less than 3 %.
Results and discussions
The dynamic surface modulus (G’ storage and G’’ loss) is shown in Figure 1 in a semi-logarithmic plot. The adsorption to the air-water interface had only a slight effect on the viscoelastic properties. There was no network formation, the adsorption ended to a plateau and the viscosity dominated during the whole experiment. In the oil-water experiment the interfacial elasticity clearly developed faster than the interfacial viscosity and a gel point was reached after approximately 11 600 seconds (3.2 hours).

Attension

2011-03-18T22:37:00.000-07:00

http://www.attension.com/applications.aspx/

http://www.attension.com/tensiometers.aspx/

Attension Sigma 700

2011-03-18T02:20:00.000-07:00

Installation in Malaysian Top University Sigma 700 complete system

LPR technique

2011-02-23T01:50:00.001-08:00

The LPR technique is the most frequently used being both quick and easy. A small sweep from typically -10 mV to +10 mV at 10 mV/min around the rest potential is performed. The resulting current/voltage plot usually exhibits a straight line the inverse slope of which is proportional to the corrosion rate. The Gill AC Gill 8 and 12 the Field Machine the Pocket Machine the LPR meter and the Bubble Test software all use this method.

New Office

2011-02-18T02:57:00.000-08:00

KULIM HI-TECH SDN.BHD.

A3-03, BLOCK A, SRI HIJAUN,

NO. 1, JALAN BUKIT HIJAU 26/24

SECTION 26, 40400, SHAH ALAM.

SELANGOR DARUL EHSAN

TEL: 603-5192 5110: FAX 603-51920501: Cell: 6016-6339009

azaham@tm.net.my

Theta touch on contact Lens

2011-02-15T07:46:00.000-08:00

Captive bubble method in contact lens studies

Contact lenses are widely used and hydrogel contact lenses are the most

prescribed type of contact lenses around the world. Hydrogel lenses are made from

hydrophilic polymers, such as polyhydroxyethyl. Contact lenses should have certain

characteristics to avoid discomfort during wear. These include an adequate oxygen

permeability, lens motion and surface wettability. A fairly recently discovered

material for contact lens manufacturing is the silicone hydrogel, which is suitable for

long term use as it has improved oxygen delivery on the ocular surface. However,

this material has been reported to have reduced wettability compared to the other

materials used in hydrogel contact lenses.

The wettability of a lens is measured on the abilities of the lens to support a

continuous and rupture-resistant tear film on its surface. A lens with a limited

wettability is uncomfortable and has a reduced visual performance. Therefore it has

been a major investment for the contact lens industry to develop a soft lens surface

that is highly wettable in the ocular environment.

How to study the wettability of contact lenses?

Contact angle measurement is the most common method used to characterize

wettability of solid surfaces. There are a variety of contact angle techniques that can

be used for this purpose: the sessile drop method and the captive bubble method.

Sessile drop and captive bubble methods can also be used simultaneously to

measure the different contact angles of a lens. Sessile drop method can be used to

examine the advancing contact angle and captive bubble method to obtain the

receding contact angle. Both of these contact angles can also be obtained only by

captive bubble method. Captive bubble method is very useful as it is possible to

maintain fully hydrated conditions on the lens surface during the experiment. This is

essential as the drying of the lens causes the setup to be far from the ideal

conditions. Figure 1a illustrates the sessile drop method, where a drop of water is

replaced on a glass slide. The contact angle obtained with this method was 140°. In

Figure 1b the contact angle of an air bubble in water is obtained with the captive

bubble method and it is calculated to be 40°. Contact angle hysteresis is the

difference between the advancing and receding contact angles. It can be used to

characterize the surface roughness, chemical heterogeneity, re-arrangement of

molecules at the surface, solid swelling and mobility. In highly water wetting lenses

the contact angle hysteresis is eliminated and both the advancing and receding

contact angles approach zero.

Captive bubble technique

In the captive bubble method the contact angle is measured by placing a bubble of

air onto the lens surface with a capillary while the lens is immersed in a liquid.

Preferably the lens should be soaked in liquid for a couple days before the

measurement takes place in order to get the lens fully wet. The conditions in this

experiment should mimic the in vivo conditions as good as possible, meaning that

the liquid used in the contact angle experiments should be close to the real nature

of a tear film in the eye. The tear film is composed of surface active components

such as mucin and lysozyme.

Receding and advancing contact angles are both important measures of contact

lens wettability. A receding angle forms as the water phase moves away from the

capillary. This corresponds to the situation when the eyelid is open and the tear film

starts rupturing on the lens. The advancing contact angle develops as the water

phase moves towards the capillary. This is the case when the eyelid closes and the

tear film on the lens starts to recover.

A solution for finding improved wettability?

With captive bubble method contact angles of lenses can be measured in different

solutions to obtain the most ideal solution that wets the lens best. Some have

reported that significant change can’t be seen in whether the solution is pure water

or a liquid containing surfactants (like the contact lens solutions on the market).

Also studies of different coatings to improve the lens wettability have been made.

Protein coatings have found to be successful in improving the wettability of contact

lenses. Protein coatings resist the tear protein adsorption and deposition into the

lens.

QCM-D

2011-02-03T17:47:00.000-08:00

QCM-D Technology

By collecting both the dissipation and the resonance frequency of a quartz crystal,
QCM-D technology can be used to characterize the formation of thin films (nm) such as proteins, polymers and cells onto surfaces, in liquid. This is QCM-D, Quartz Crystal Microbalance with Dissipation monitoring, Q-Sense's proprietary sensor technology.

In liquid, an adsorbed film may consist of a considerably high amount of water, which is sensed as a mass uptake by all QCMs. By measuring several frequencies and the dissipation it becomes possible to determine whether the adsorbed film is rigid or water-rich (soft) which is not possible by looking only at the frequency response. The amount of water in an adsorbed film can be as high as 95% depending on the kind of molecule and the type of surface you are studying. Picture elongated molecules - if they would adsorb flat on the surface, little water will be coupled to the molecules. However, if they adsorb standing up at the surface, lots of water will be coupled. With QCM-D the kinetics of both structural changes and mass changes are obtained simultaneously.

Would you like to ask specific questions or gain more information about the QCM-D technique? You are welcome to contact us at any time.

The QCM-D Principle

Unlike all other QCMs, QCM-D monitors the response of the freely oscillating crystal, which is faster and more accurate than the usual frequency sweep principle.

KSV NIMA LB ACCESSORY and MODULE

2011-01-28T01:39:00.000-08:00

We are happy to announce the new KSV NIMA LB ACCESSORY and MODULE document. It will help everybody to easily see what modules are available, how they can be combined, and what they look like. At the same time we also have an updated version of the LB product brochure. The technical specifications and compatibility table now has the KSV NIMA BAM and KSV NIMA MicroBAM listed on separate lines showing which system they can be used with.

Both of them can be found online on the KSV NIMA Langmuir / Langmuir-Blodgett web page. (http://www.ksvnima.com/langmuir-and-langmuir-blodgett-troughs)

ASTM D971 standard.

2011-01-27T00:40:00.000-08:00

Performing an interfacial tension measurement

between water / oil according to ASTM D971 standard.

1. Check the instructions in section 5.1 and make necessary preparations.

2. Set oil density to correct value. You may also measure the density of the

oil (see section 5.2).

3. Make sure that the correction method of your preference is selected. You

can change the active ring correction method from Adjust parameters

menu. To be strictly compliant with ASTM D971 standard, choose

Zuidema-Waters. However, Huh-Mason is a more modern method that is

generally regarded more accurate.

4. Pour distilled water at a temperature of 25 ± 1°C into cleaned sample

container to a depth of 10 to 15 mm. Place it in to the middle of the

tensiometer platform. Make sure no foam is present at the water surface.

If foam is visible, discard the water. Foam indicates that the water is

contaminated or that the vessel is not clean.

5. Mount the ring in the tensiometer hook. If the oil to be measured is denser

than water, the measurement must be performed in Push Mode1, and the

supplied weight therefor needs to be attached to the ring before mounting

the ring.

6. Select "Measure oil interface" from the menu selection and press the OK

button. Sigma will now measure automatically the surface tension of the

water. Wait until the measurement has completed. If the measurement

was successful, the ring will automatically descend back into the water,

except in the case of Push Mode measurement with dense oil, however,

the ring will remain about 5 mm above the water.

7. When the ring has stopped moving, carefully layer the oil on the surface of

the water, until an oil layer of at least 10 mm is reached2. Do not move

the sample container from tensiometer platform, nor move the ring.

8. Press the OK button right after the oil pouring is finished. The tensiometer

will then wait for 29 seconds (as the standard requires a wait between 29

and 31 seconds), until it starts the measurement of the interfacial tension

between water and oil. Wait until the measurement has completed.

9. Interfacial tension value is shown on the display.

As the ring is pulled through a surface or an interface, a curve is plotted,

showing the tension value calculated from the balance reading at each

instant. The highest value encountered will be displayed as the result of the

measurement.

1 If the oil is denser than water, it forms a layer below water and interfacial tension must

measured by pulling the ring downwards from water to oil; hence the name Push Mode. The

case of Push Mode measurement is not explicitly addressed in ASTM D971 standard.

2 Layering the oil should not take more time than 30s since completing the entire interfacial

tension measurement have to be done within 60s ±10s

ICENV 2010 IN PENANG

2011-01-03T01:26:00.000-08:00

Farfield’s AnaLight® 4D Workstation

2011-01-03T01:19:00.000-08:00

Introducing Farfield’s AnaLight® 4D Workstation

DUAL PLATE AUTOSAMPLER

We are pleased to introduce the new Dual Plate Autosampler for

Farfield’s Dual Polarisation Interferometer. This provides the most

advanced technology for automated sample care.

Some of the key features are:

State‐of‐the‐art injection technology

Efficient multi–solvent needle wash

Accurate sample cooling down to 4°C

Vials, 96 and 384 well formats

Dual microtitre plate capacity

Fast injection and wash cycles

Fully integrated with AnaLight® software

Conferences and Seminars

Farfield will be attending the following conferences and seminars.

Bill 2011—Grenoble, France January 12–13

Lorne Protein Structure and Function—Victoria, Australia February 6‐10

Biophysical Society—Baltimore Maryland, USA March 5‐9

ACIhE Conference—Chicago, Illinois USA March 13–19

ACS—Anaheim, California USA March 27‐31

Please visit our website for a full listing of events and conference links; http://www.farfield‐group.com/news_events_ec.asp

PHOTORESIST POLYMERS

2010-12-29T18:45:00.000-08:00

QCM-D TO STUDY DISSOLUTION MECHANISMS IN PHOTORESIST POLYMERS

INTRODUCTION
Many newly developed photoresist
polymers swell when exposed to the
developing solution, which is used
when creating a microlithographic
structure with photoresist polymers.
For these polymers, the effects on the
rate of dissolution due to the swelling
process are poorly understood.
The study reported in this application
note explores the response of a thin
film to an aqueous alkaline solution
as a function of the composition of the
polymer as it changes. The study was
conducted in real time using Quartz
Crystal Microbalance with Dissipation
monitoring (QCM-D). The reported
data challenges the current models
of photoresist polymer film dissolution
mechanisms that do not take into
account the swelling properties of the
film.

Surface Plasmon Resonance (2 Channels/exchangeable cuvette)

2010-11-26T20:52:00.000-08:00

Introduction:

Metal-organic frameworks (MOFs) are crystalline supramolecular assemblies that are built up from precisely defined subunits by coordination or covalent interactions [1]. MOFs are usually highly porous, and they offer a wide range of applications where incorporation of guest molecules are needed. Applications include fuel storage, catalysis, drug delivery and gas sensing. Recently a layer-by-layer (LbL) method for building such materials has been introduced, which offers more control on the MOF structure. [1,2]Surface Plasmon resonance (SPR) is a highly sensitive optical method that measures changes in refractive index (RI) near a metal surface, even as small changes as 10-6 RI units. [3] In the Kretschmann configuration, the SPR signal is excited and measured from the “dry side” of a metal coated sensor slide, which makes it possible to measure highly light-absorbing or turbid solutions. Due to the high sensitivity, SPR has traditionally been a tool for biochemists for measuring biomolecular interactions in solution. However, because the SPR phenomenon is not selective, it can also be used for nanoscale material science as well. Apart from only measuring relative changes in the intensity at fixed angles or angular position, the SPR Navi 200 also allows collection of the complete SPR curve with absolute angle information thus enabling optical constants and thickness determination of nanoscale films both in gas and liquid phases.

adsorption studies can provide valuable insight into the mechanism of asphaltene deposition.

2010-10-26T20:57:00.000-07:00

ANALYSIS OF ASPHALTENES AND CRUDE

OIL ADSORPTION ON SURFACES USING QCMD

Surface interactions of asphaltenes

in crude oil represent

an important issue for

the petrochemical industry.

QCM-D technology is helpful

for evaluating different approaches

to solve these problems.

In particular, the ability

to monitor different structural

arrangements of adsorbed

materials is useful for understanding

how asphaltenes adsorb

to surfaces.

QS 405-25-1

Introduction

Every day, the complex petroleum

industry faces the challenge of

handling fouling, altered wettability

and coking. A major cause of these

problems is the adsorption of petroleum

heavy ends at solid/liquid

interfaces that occurs at different

stages of oil production. Among

heavy ends in petroleum, asphaltenes

are often considered the

most problematic because of their

chemical nature and their tendency

to aggregate and form deposits under

certain pressure, temperature

and composition conditions.

CONCLUSION

QCM-D enables real-time characterization of asphaltene (in crude oil,

or purified from crude oil) adsorption onto different surfaces. The adsorbed

amounts and characteristics of adsorption depend on the solubility

state of the asphaltene as well as its origin. Furthermore, surface

adsorption varies to a small extent between different hydrophilic sensor

coatings.

Palm Oil Industry

2010-10-11T19:02:00.000-07:00

Cloud point

Cloud Point is the temperature at which the oil begins to cloud resulting from crystallisation under controlled cooling. The CP is related to the unsaturation of the oil. In general the higher is the unsaturation, lower will be the CP. The initial quality of crude palm oil CPO (diglycerides, FFA,…) has strong influence of the CP of the oleins. Due to often misinterpretations here the AOCS Official Method Cc 6-25 . (1993)

Definition : The cloud point is that temperature at which, under the conditions of this test, a cloud is induced in the sample caused by the first stage of crystallization.

Scope : Applicable to all normal animal and vegetable fats.

Apparatus

Oil sample bottle–115 mL (4 oz).
Thermometer–range –2–68°C, AOCS Specification H 6-40.
Water bath-made up of water, chipped ice and water; or chipped ice, salt and water, depending on the temperature required. The temperature of the cloud point bath shall not less than 2˚C, nor more than 5˚C below the cloud point. Either a beaker or insulated container is convenient for the test.

Procedure

The sample must be completely dry before making the test. If the sample contains traces of moisture, it should be filtered through suitable filter paper. Heat 60-75 g of sample to 130˚C (see Notes, 1) just before making the test. Pour 45 mL of the heated fat into the oil sample bottle.
Begin to cool the bottle and contents in the water bath, stirring enough to keep the temperature uniform. When the sample has reached a temperature about 10˚C above the cloud point, begin stirring steadily and rapidly in a circular motion so as to prevent supercooling and solidification of fat crystals on the sides or bottom of the bottle.
From this point on, do not remove the thermometer from the sample : doing so may introduce air bubbles which will interfere with the test. The test bottle is maintained in such a position that the upper level of the sample in the bottle is level with the water in the bath.
Remove the bottle from the bath and inspect regularly. The cloud point is that temperature at which that portion of the thermometer immersed in the oil is no longer visible when viewed horizontally through the bottle and sample.

Notes

It is essential that the sample be heated to 130˚C to destroy any crystal nuclei.

Krafft point

The temperature (more precisely, narrow temperature range) above which

the solubility of a surfactant rises sharply. At this temperature the solubility

of the surfactant becomes equal to the critical micelle concentration. It is

best determined by locating the abrupt change in slope of a graph of the

logarithm of the solubility against t or 1/T.

or in other word

The Krafft temperature (also known as Krafft point, or critical micelle temperature) is the minimum temperature at which surfactants form micelles. Below the Krafft temperature, there is no value for the critical micelle concentration (CMC), i.e., micelles cannot form. The Krafft temperature is a point of phase change below which the surfactant remains in crystalline form, even in aqueous solution.

Surfactants in such a crystalline state will only solubilize and form micelles if another surfactant assists it in overcoming the forces that keep it crystallized, or if the temperature increases, thus causing entropy to have a stronger force and encouraging the crystalline structure to break apart

Webinar on Qtools modeling

2010-10-07T21:21:00.000-07:00

As QCM-D monitors events as they occur, it is a valuable tool in understanding molecular changes at the surface. QCM-D can determine the mass of very thin surface bound layers while also providing simultaneous data about the layers’ viscoelastic properties, which indicates the structural properties of adsorbed molecular layers.

By revealing structural details and mass at the same time, QCM-D gives researchers the information they need to assess the impact of surface modification or to characterise molecular interactions.

The next webinar on Qtools modeling is scheduled Monday 11th of October 15.00 Swedish time. Only 10 people per session can be there so make sure your customers get this email in time for registration.

More info and how to register can be found here: https://q-senseab.webex.com/mw0305l/mywebex/default.do?siteurl=q-senseab&service=7

Force Tensionmeter

2010-09-21T22:09:00.000-07:00

Surface tension, γ

A molecule in the bulk of a liquid experiences

an equally attractive force in all

directions, but at the surface there is more

attractive force in the direction of the bulk

than away from it. This reduced attraction

at the liquid-gas boundary gives rise to the

measurable property of surface tension.

At the liquid-liquid phase boundary, it is

referred to as interfacial tension. Surface

tension can be measured with optical,

force, volumetric or bubble tensiometers,

while interfacial tension can be measured

with force and optical tensiometers.

Contact angle, θ

Surface tension alone does not explain

the shape of a drop along a solid. Interaction

between the liquid and solid can be

attractive or repulsive. When attracted

by the solid, the liquid spreads, forming

short drops with low contact angles. If

repelled, the drops are taller, rounder and

have high contact angles. The lotus effect

is a special case of water repelling, or

hydrophobic, behavior. The microstructuring

of a leaf makes the surface superhydrophic,

causing a rain droplet to roll

off by itself.

Surface free energy

Surface free energy is surface tension for

solids. Like in liquids, surface molecules in

solids have more attractive forces towards

the bulk than away from it. This leaves the

surface molecules inclined to attract neighbouring

substances, so the higher the

surface free energy the easier it is to wet a

substrate. In contrast to liquids, the surface

free energy of solids cannot be measured

with tensiometry but via contact angle

measurements with a range of liquids.

http://www.attension.com/force-tensiometers.aspx

Farfield DPI Technology Applications

2010-09-14T07:31:00.000-07:00

Biophysics Applications: Visit your application areas of interest in Biophysics to view or download PDFs of Farfield's AnaLight® application notes:

Surface Science Applications: Visit your application areas of interest in Surface Science to view or download PDFs of Farfield's AnaLight® application notes:

Why do biotech companies spend billions on developing protein drugs that later prove not to work ?

2010-09-13T09:22:00.000-07:00

One answer is that the development of protein drugs is a highly complex task. Firstly, protein drugs are made of protein structures that are difficult to design and manufacture. Secondly, protein drugs are made to affect complex processes in the body, processes of which we sometimes have limited knowledge.

Often, the biotech company succeeds in the design and manufacture of a protein suitable for its purpose. But still, it turns out to be inefficient, due to the fact that proteins are not stable. They can have a tendency to change their internal structure in an unwanted way. Or they may aggregate, in the packaging where they are stored or while it is being injected into the body. If the biotech company could predict this behaviour of its proteins, it could make efforts to modify its proteins and make them work, making great savings in their R&D spending.

We contribute by providing QCM-D technology. Q-Sense products contain a measurement chamber, which is utilized as a reaction chamber for a large variety of proteins. In addition, Q-Sense has built up a considerable knowledge base to support customers dealing with these highly complex issues.
www.biolinscientific.com.

QCM-D and SPR technology

2010-09-13T08:53:00.000-07:00

Hydrogen would be a great and clean fuel, but how do we store it ?

Hydrogen is the most common chemical element in the universe. And since it is involved in the transformation of energy on the sun, you don’t have to be a rocket scientist to realize it has a potential as a fuel. In the presence of oxygen, hydrogen is extremely flammable and it could therefore be used in combustion processes.

It is believed that hydrogen gas could be a strong candidate to replace fossil fuel in cars and as energy source also for very small devices, such as mobile telephones. Hydrogen is present in ordinary water, which we have lots of. When it combusts, it creates no carbon dioxide which would affect global warming.

However, there are some problems. Firstly, it takes a lot of energy to break out hydrogen from water. Secondly, hydrogen is evanescent and highly flammable, making it difficult to store and transport. Let’s hope that scientists figure these issues out so that we can start utilizing this easily accessible and environment friendly fuel !

We contribute by providing QCM-D and SPR technologies. These technologies, utilized in combination, have been used by researchers who try to analyze how hydrogen can be deposited in a bead of nanoparticles. Within Biolin Scientific there is eagerness to contribute more to the development of cleaner technologies.
www.biolinscientific.com

Visit KHT at ICENV 2010 on the13th to the 15th of December

2010-09-06T21:37:00.000-07:00

http://www.attension.com/icenv-2010-penang-malaysia.aspx

http://www.ksvnima.com/icenv-2010

Measuring a Conformational Change

2010-09-01T22:00:00.000-07:00

Proteins, the building blocks of life, are wonderfully complex

molecules whose correct function is essential to all biological

processes and whose malfunction lies at the heart of almost

every disease. Part of the complexity and subtlety of their

operation rests in the fact that it is not merely their chemical

composition but their shape (conformation) that determines

their characteristics. In response to pH, ionic strength, or other

molecules binding to them, proteins can open and close,

changing shape and, as a result, the a allocated function.

For many years, biochemists and pharmacologists have

worked to determine precisely the consequences of a protein's

3‐D shape, in order to gain a better understanding of

how they operate or how drug molecules could be designed to

assist in function or mediate in malfunction. Images of protein

crystal structure are of intense interest to the pharmaceutical

industry, but these are static snapshots of what are elegantly

mobile mechanisms and provide only one fragment of the

information required to unravel the mysteries of proteins.

Furthermore, imaging a protein using x‐ray diffraction requires

first crystallizing the protein, an extremely difficult process (fortunately for the existence of life!) that has seriously restricted the

number of useful images that have been obtained to date.

Researchers require an analytical approach with which they can study a protein in a more native environment, measure protein

structure in real time and at a resolution likely to yield information about its function, and directly correlate any conformational

changes with protein activity. Dual Polarization Interferometry (DPI) provides just such a method.

DPI measures the conformation of a protein in one dimension (i.e., its diameter or size) and the density (i.e. its mass per unit volume

or how tightly folded it is) by coupling the protein to a glass slide and probing its structure using non‐diffractive optics. The method

resolves protein structure to subatomic dimensions (well below 0.1 Å) in real time and has a

growing acceptance among researchers in the field of protein characterization, an essential

discipline in the science of proteomics.

Operating Principles

How can you measure dimensions as small as this with an optical instrument using a

wavelength of light (632nm) which is ~10,000 times larger? DPI achieves this by making these

measurements with respect to a buried optical reference. A sensing optical layer (i.e.

waveguide) is constructed above this reference optical layer in a disposable glass slide. Light

traveling through both layers is projected onto a camera creating an interference pattern.

Molecules are captured on the sensing waveguide which changes its refractive index which in

turn moves the interference pattern. This movement is directly related to both the refractive

index and the thickness of the molecular layer. However with a single measurement one could

not resolve the difference between a thick layer with low refractive index and a thin layer with

high refractive index. This ambiguity is removed by taking a second measurement using an

orthogonal polarisation which provides another unique response. Resolving both responses

gives an unambiguous value for both the dimensions and refractive index of the molecular

layer.

The movement of the fringe pattern is referred to as a phase change and the phase changes of

interest, Δφ involve changes to the effective refractive index Ns of the mode in the upper

(sensing) waveguide. Changes occurring at the surface do not alter the effective index of the lower (reference) mode Nr, because the evanescent field of this mode decays rapidly in the region between the two layers.

The phase difference is given by Δφ=k0LΔNs (1)

where k0 is the free space wave number, L is the interaction length, and ΔNs is the effective index change in the upper waveguide mode. Direct measurement of Δφ is obtained by continuously monitoring the relative phase position of the fringe pattern by performing a Fourier transformation relating intensity (of the fringe pattern) to position. The path length is fixed, so one can thus easily convert the experimental data to changes in effective refractive index.

NEW INNOVATIVE TECHNIQUE FOR ACCELERATED CORROSION MEASUREMENT & AUTOMATIC INHIBITOR CHEMICAL OPTOMIZATION

2010-08-28T20:30:00.000-07:00

Traditional HPHT Autoclave designs have been enhanced by the introduction of real-time corrosion measurement instruments and probes, to accurately reproduce the multiphase flowing field conditions of operating pipelines and industrial environments.

Corrosion Measurement - Early Practices

Shear Stress Measurement- Effect of Velocity on Corrosion- Laminar Flow Studies

Corrosion Modeling- Multiphase Studies Accelerated Pipeline Integrity

Automated Inhibitor Injection (A.I.I.)- “Feedback” Chemical Pump Control

Corrosion Measurement

For many decades’ production and pipeline operators used simple corrosion coupons as an intermittent corrosion weight loss measurement. NACE, ASTM and others made exhaustive attempts to upgrade the method, Conducting Corrosion Coupon Tests in Plant Equipment, ASTM G4-84 originating (A224-39) in 1939.

Additional test methods were developed by NACE and others, as example TM01-77-96, Laboratory Testing of Metals for Resistance to Sulfide Stress Corrosion Cracking in H2S Environments. The standard addressed “the testing of metals for resistance to cracking failure under combined action of tensile stress and corrosion in aqueous environments containing Hydrogen Sulfide (H₂S)”.

Shear Stress Measurement

The 1995 NACE Publication 5A195 State Of-The-Art on Controlled Flow Laboratory Corrosion Tests was a “compilation of experimental techniques intended to provide the most up to date information available at the time on evaluating the effect of velocity on corrosion”, called Shear Stress. Included in NACE #5A195 (but not limited to) were the contents:

Interpretation of Lab Measurements
Philosophy Behind Experimental Design
Experimental Systems
References
Appendix B Governing Equations:
Rotating Disk
Rotating Cylinder
Impingement Jet
Flow-Loop System

In 1996 NACE Publication #1D196 Laboratory Test Methods for Evaluating Oilfield Corrosion Inhibitors, coupled the above NACE #5A195 with the effects of chemical inhibitor applications under multiphase flow controlled test equipment for lab simulations.

During recent decades, ER/LPR became viable techniques adapted from lab studies and applied in the form of probes and instruments developed for long-term field studies.

Modern electronic components and high speed data acquisition evolution allowed a more rapid response corrosion rate measurement to be made in real time. The new probe/instrument system could be used to make measurements not only in electrolytic, but in non-conductive gas environments as well. The rapid response Systems have been readily accepted by the corrosion community as touted in NACE Papers 1997 #288 A Critical Comparison of Corrosion Monitoring Techniques in Industrial Applications, and later in NACE 2000 #00090 Field Trial Results of a New Rapid Corrosion Monitoring System

Automated Inhibitor Injection

Complimenting the high shear and impingement measurements, new Automated Inhibitor Injection (A.I.I.) systems are in operation since 1998 using the rapid response corrosion rate output signal to determine and control the optimum inhibitor chemical dose rate using variable flow rate inhibitor chemical injection pumps.

CONCLUSION

Cost of corrosion and its associated long terms costs can be significantly reduced with properly configured laboratory HPHT simulation systems, in combination with the newest state-of-the-art A.I.I. skid installations. The initial cost of these systems is quite small compared to the potential savings in material assets, non-productive downtime, the global environment and personnel safety.

G. W. Mazurk Sr. Vice President Cortest, Inc.

www. cortest.com

RESEARCH-GRADE DUAL AUTOCLAVE SYSTEM

2010-08-26T21:40:00.000-07:00

RESEARCH-GRADE DUAL AUTOCLAVE SYSTEM

Research Project:

Physical and corrosion properties of pipeline, downhole and refinery steels and alloys

Optimization of anti-corrosion chemicals inhibitor formulations and dosage rates

Cost Savings Relation of Laboratory Test Results to Field Operations:

Materials of Construction

Material’s selection decision can be greatly improved by evaluating the material’s performance at high temperature and high pressure in a laboratory autoclave. These systems are very versatile, permitting short term tests for inhibitor screening, medium term electrochemical evaluations, and very long-term exposures. From these results, informed decisions can be made to optimize cost vs. performance of materials used in pipelines, valves, fittings, pumps, pressure vessels, and heat exchangers.

Corrosion Inhibitors

Inhibitor performance can be evaluated using multiple techniques in autoclave systems. Shear stress measurements using jet impingement or rotating cylinder tests can accurately define inhibitor performance, permitting selection of proper formulations.

PURPOSE OF RESEARCH

This dual autoclave system is necessary to accelerate tests screening results and support the I0 Dynamic Multiphase Test Loop according to ASTM G170-01a, Paragraph 4, Summary of Guide, attached.

In accordance with ASTM and NACE Test Method Standards; accurately simulate the physical field operating conditions and easily screen material samples fitting NACE and ISO recommended practices.

a) Study corrosion behavior and effects of field operations and oil/gas chemicals from down hole to refinery, including seawater, oxygen, CO₂/H₂S (and other gases) and effect of flow on the surfaces of subject screening material’s test specimen.

b) Characterize the corrosion product films that adhere on materials.

c) Study the effectiveness of the anti-corrosion inhibitor chemicals for all environments, from down hole to pipelines, to storage and refinery field applications.

d) Understand and apply the test results of the measured corrosion behavior and corrosion resistance.

LITERATURE REVIEW

Lab test equipments will fully conform to ASTM G170-01a Standard Guide for Evaluating & Qualifying Oilfield& Refinery Inhibitors in the Laboratory

www.cortest.com

Surface Plasmon Resonance (2 Channels/exchangeable cuvette)

2010-08-26T02:26:00.000-07:00

SPR

SPR Navi 200, the versatile SPR system for surface science. Surface molecular interactions Nanoscale film properties, Langmuir-Blodgett films.

Self-assembled monolayers, Spin and dip-coated layers, Non-dielectric films

Application notes are provided at our web site: www.bionavis.com

SPR and Nanoscale films. Physics and material sciences Bio-material films SwellingAdsorption/absorption- Membrane properties, Gas sensors

Surface Plasmon Resonance has been established as a powerful method to monitor label-free biomolecular interactions in liquids. However, today SPR can deliver well beyond kinetics and equilibrium constants: you can expect more from SPR with SPR Navi 200.With SPR Navi 200 – an incident beam of p-polarized light strikes an electrically conducting gold layer at the interface of a glass sensor (high Refractive Index) and an external medium with low RI (gas or liquid).At a given angle, due to a resonance phenomenon, light is exciting surface plasmons at the interface – resulting in a reduced intensity of the reflected light.A slight change at the interface (e.g. a change in refractive index or nanoscale film thickness) will lead to a change in SPR signal – allowing precise measurements of nanoscale film properties as well as surface molecular interactions.

BioNavis’ SPR Navi 200 System uses an increased angular scan range that produces a complete SPR curve. This increased angular range allows you to simultaneously characterize surfaces in gas and/or liquid. This also allows you to check the quality of user-defined surfaces before sample injection. This broadens the scope of your measurements.In addition to traditional biophysical interaction phenomena, you can characterize optical constants and thicknesses of nanoscale structures.

You can measure:

Surface-molecular interactions, Nanoscale film properties :

Langmuir-Blodgett films Self-assembled monolayers

Spin-and dip-coated layers Non-dielectric films

Physics and material sciences- Bio-material films:

Swelling Adsorption/absorption Membrane properties

Gas sensors:

BioNavis Ltd was established to develop, manufacture, supply and support Surface Plasmon Resonance (SPR) based instruments and sensors for research and diagnos-tics. The Company was founded in 2006 by private inves-tors and professionals with several decades experience in scientific instrumentation, to take over and further advance the SPR technology primarily developed at VTT - Technical Research Centre of Finland. Counting the previous devel-opment at VTT, there are more than 15 years of accumu-lated development history in the BioNavis SPR technology. BioNavis holds several international patents related to the SPR techniques and its applications.The mission of BioNavis is to respond customer needs by developing sensors, methods and research instruments which have clearly better features and performance as compared to competitors, but with affordable price.

The SPR instruments are mainly targeted to research of molecu-lar interactions, and are used by researchers in physical chemistry, biochemistry, pharmaceutics, biotechnology, and medical diagnostics.SPR Navi 200 has been developed in collaboration with Dr. Janusz Sadowski who has been the main driver in the research of SPR technique at VTT for over 20 years, and Dr. Ulf Jönsson, the founder and former CEO of Biacore, the company that pioneered the use of SPR spectroscopy for protein interaction analysis.BioNavis Ltd is based in Tampere – Finland – and provides worldwide distribution and local customer support via its fully trained and capable global network of distribution partners.

Application notes are provided at our web site: www.bionavis.com

Biophysical Characterisation

2010-08-25T00:26:00.000-07:00

Introduction to Biophysical Characterisation

using Dual Polarisation Interferometry

Dual Polarisation Interferometry (DPI) is a highly versatile, powerful analytical technique for

biophysical characterisation of proteins and other biomolecules. It extends the typical dynamic

measurements of conventional biosensors by including an additional quantitative, sub molecular,

conformational measurement.

DPI delivers a unique perspective on biochemistry, linking conformational changes to biochemical activity at a resolution normally associated with ‘big physics’.

DPI is an interferometric technique to derive dynamic information concerning the thickness,

density and mass of the molecular layer. As well as mass-based affinity and kinetic

determinations possible with other label-free optical and acoustic biosensor technologies, DPI

additionally provides real-time data on the orientation of the surface immobilised layer and

any conformational changes involved upon binding.

Two polarisations of light are passed through the sensor which consists of an upper ‘sensing’ layer and an embedded ‘reference’ layer. The output from each of the layers then combine producing two interference patterns which are detected by a camera. As molecules bind (or change shape) on the surface of the ‘sensing’ layer, they are probed by the evanescent field from the ‘sensing’ surface. This, in turn, changes both interference patterns. As material binds, the interference pattern shifts one way.

As material is removed from the surface, the interference pattern returns.

The AnaLight® Resolver software automatically analyses both sets of data and outputs the real time changes in the thickness, density and mass of the molecular layer. All of the calculations are based on classical optics theory and have been independently validated by, amongst others, the National Physics Laboratory (NPL) in the UK.

Meeting the Challenges of Glycobiology

2010-08-23T23:28:00.000-07:00

Glycobiology has emerged as an important area of biology, greatly facilitated by recent advances in biophysical measurement and characterisation of glycan structures. The field is made more complex as carbohydrate biochemistry is epigenetic with an infinite variety of structures that can be variable, but still retain a specificity of action or a regulatory function.

The Problem: The advent of MALDI-TOF has made it possible to derive high resolution structural information concerning glycan structures. However, such data is derived from static measurements at equilibrium, rather than from a a dynamic measurement of the mode of interaction of that structure with any of its biologically relevant molecular partners. Dynamic mass-based measurements have been conducted via such biosensor technologies as surface plasmon resonance (SPR). Such studies have been hindered by the relatively low affinity of sugar-based interactions and the practical issues of working at high sugar concentrations where prominent bulk refractive index effects interfere with the basic measurement principle.

The Solution: Dual Polarisation Interferometry (DPI) is increasingly being deployed in glycobiology as it’s inherent sensitivity and large dynamic range allow the user to work with high sugar concentrations. Additionally, a more complete biophysical characterisation is possible with quantitative measurements being determined in molecular size, density, birefringence and mass in real time. With DPI it is now possible to measure the mechanisms underlying the biomolecular interactions involving sugars together with the reaction rates and affinities of interaction.

www.farfield-group.com

Potentiostat with autoclave

2010-08-10T01:00:00.000-07:00

The potentiostatic test is usually performed to determine resistance to pit initiation at a given potential and to simulate galvanic situations using any of Gill AC 8 12 Field Machine and manual potentiostat set to a stable potential whilst recording the current. In the study of pitting the cyclic sweep method can have problems related to sweep rate and too much pitting propagation before sweep reversal. The use of individual samples held at potentials around the suspected pitting potential will allow the correct determination of the pitting potential.

KSV LB advantages

2010-08-09T01:58:00.000-07:00

Advantages of KSV L- and LB film instruments compared to competitors’ instruments
In most countries KSV has local support and service, which most of our competitors don’t have.
KSV has the capability for on-line digital displays to show real time status of surface pressure, substrate position during deposition, dipper speed, barrier position, temperature, pH, surface potential, lateral conductivity or display of signal from customers own measuring devise.
The use of digital displays makes practical work more convenient because the course of experiment and real time status or each measuring parameter can be followed in clear digits in the front panel of the instruments power supply tower. The same data is shown on-line also on the PC monitor both in graphical and numerical mode. However, drastic, expected or minor changes are more difficult to detect from the PC monitor x/y axis. From digital display one sees the status of the experiment and can instantly re-program the instrument if needed e.g. to slow down, increase or stop functions. Sometimes valuable experiments can be saved if changes in the progress are detected early.
Competitors have no digital displays.
KSV has as an option a remote control keypad to drive the barriers and dipper without PC control. This feature becomes useful when cleaning the surface from the film and when setting the system into starting position or when ending the experiment. The user can be very close to the instrument to control and observe its operation while the PC is disconnected. Sometimes the instrument can be a distance away from the PC and to control the preparative procedures from PC can become cumbersome especially if operator don’t see the operation and if there is programming involved.
Competitors have no manual control unit available and all movements must be pre-programmed.
All KSV LB instruments are designed so that the troughs are exchangeable and can easily be removed from the instrument for cleaning for example in a separate cleaning bath. This enables the exchange of troughs for different purposes i.e. from normal monolayer troughs to dipping, enzyme or polymerisation kinetics, lateral conductivity, two compartment troughs etc.
KSV design is more sophisticated; barrier drive belt, linear motion rail and riders, cogs (=toothed wheels) and DC-motor are all covered to protect accidental water spillage and to prevent dust collecting on the surfaces. Most of competitors systems all these are not covered.
KSV LB balances have a much larger measuring range (0-250 mN/m) than competitors (0-175 mN/m).
KSV has one piece (no glue sealing in the dipping well) PTFE trough as standard. Competitors have it as option, if at all.
KSV has symmetric compression by two barriers as standard. Most competitors have this as an option.
KSV has the dipping in the centre of the trough. Most competitors have this as an option.
KSV uses hydrophilic (Delrin) barrier material to avoid film leakage. The hydrophilic material draws the water molecules against the bottom of the barrier and the front edge of the barrier. The film can not escape from under the barrier. Some competitors use force to push down hydrophobic (PTFE) barriers in an attempt to avoid the film leakage under the barrier. Force increases the friction when barrier is sliding on the trough edges. Increased friction causes vibration.
All KSV LB systems are very modular and can easily be combined in any kind of configuration i.e. a film balance system for monolayer studies can easily be upgraded to a dipper system without needed to buy a whole new instrument. The troughs can be easily moved from the instrument itself for cleaning. Even multiple balances can be attached to the configuration in order to measure the surface pressure on several places over the compressed monolayer.
KSV’s alternating dipper, and trough with a clean phase in between the compartments allow built up any alternating layer structure (see KSV 2000 catalogue page 6). Stacking order can be freely selected and the hardware won’t restrict the freedom of selecting the stacking order. Additionally, KSV´s configuration enables the deposition of multiple substrates starting from the liquid phase from one monolayer experiment while in competitors troughs you need to always make a new monolayer for each solid substrate.
Competitors system does not have clean phase. This limits the stacking order.
KSV’s alternating dipper and trough system is absolutely contamination free (layer A and B can’t be mixed) as the compartments are independent troughs with boundaries. Competitors system uses seals to prevent the monolayer to enter into the dipping mechanism compartment and to the other film compartment. In continuous use the seal leaks and the risk of contamination increases.
KSV’s alternate dipper can be used as conventional LB dipper. For competitors system you must buy a separate dipper.
KSV have Windows 95/98/NT/2000/vista/win*7 software and up-dates are provided free of charge.

CONTACT ANGLE MEASUREMENT

2010-08-03T23:45:00.000-07:00

Contact Angle: Theory
The following is a short introduction to the concepts involved in the measurement of contact angles. Included is an introduction to the techniques involved and some practical advise. For those interested in further information a list of references appears at the end of this chapter.
What is contact angle?
Contact angle ,q, is a quantitative measure of the wetting of a solid by a liquid. It is defined geometrically as the angle formed by a liquid at the three phase boundary where a liquid, gas and solid intersect

It can be seen from this figure that low values of q indicate that the liquid spreads, or wets well , while high values indicate poor wetting. If the angle
q is less than 90 the liquid is said to wet the solid. If it is greater than 90 it
is said to be non-wetting. A zero contact angle represents complete wetting.

Hysteresis: For any given solid / liquid interaction there exists a range of contact angles which may be found. The measurement of a single static contact angle to characterize the interaction is no longer thought to be adequate. The value of static contact angles are found to depend on the
recent history of the interaction. When the drop has recently expanded the angle is said to represent the ‘advanced’ contact angle. When the drop has recently contracted the angle is said to represent the ‘receded’ contact angle. These angles fall within a range with advanced angles approaching a maximum value and receded angles approaching a minimum value.
The difference between the maximum(advanced) and minimum(receded) contact angle values is called the contact angle Hysteresis. A great deal of research has gone into analysis of the significance of hysteresis. It has been used to help characterize surface heterogeneity, roughness and mobility. You are recommended to the papers listed in the reference of this section for details on experiments regarding hysteresis.
Contact angle can also be considered in terms of the thermodynamics of the materials involved. This analysis involves the interfacial free energies between the three phases and is given by:
glv cos q = gsv - gsl
where glv ,gsv and gsl refer to the interfacial energies of the liquid/vapor, solid/vapor and solid/liquid interfaces.

Surface of Liquid

2010-08-03T23:29:00.000-07:00

Surface and Interfacial Tension
What is surface tension?
Surface tension is a measurement of the cohesive energy present at an interface. The molecules of a liquid attract each other. The interactions of a molecule in the bulk of a liquid are balanced by an equal attractive force in all directions. Molecules on the surface of a liquid experience an imbalance of forces as indicated below.
The net effect of this situation is the presence of free energy at the surface. The excess energy is called surface free energy and can be quantified as a measurement of energy/area. It is also possible to describe this situation as having a line tension or surface tension which is quantified as a force/length measurement. The common units for surface tension are dynes/cm or mN/m. These units are equivalent. This excess energy exists at the interface of two fluids. If one of the fluids is the vapor phase of a liquid being tested the measurement is referred to as surface tension. If the surface investigated is the interface of two liquids the measurement is referred to as interfacial tension. In either case the more dense fluid is referred to herein as the ‘heavy phase’ and the less dense fluid is referred to as the ‘light phase’. Solids also may be described to have a surface free energy at their interfaces but direct measurement of its value is not possible through techniques used for liquids. (see Contact Angle Theory section for advise on calculating solid surface free energies)
Polar liquids, such as water, have strong intermolecular interactions and thus high surface tensions. Any factor which decreases the strength of this interaction will lower surface tension. Thus an increase in the temperature of this system will lower surface tension. Any contamination, especially by surfactants, will lower surface tension. Therefore researchers should be very cautious about the issue of contamination.

QCM-D Technology

2010-07-24T22:29:00.000-07:00

Abstract
Cu(I)-catalyzed azide−alkyne [3 + 2] cycloaddition is used to construct step-by-step covalent polymer or polyelectrolyte multilayers. The catalysis involves the formation of a transient, yet rather stable, positively charged Cu(I)/alkyne complex. We demonstrate that the formation of this complex has a strong influence on the multilayer buildup process. It favors, for example, the film buildup between neutral polymer bearing alkyne groups and polyanion bearing azide groups. In contrary, it disfavors the buildup of the same neutral polymer with polycations bearing azide groups. The constructions of other multilayer systems are investigated and discussed in the light of the electrostatic interactions between these positively charged Cu(I)/alkyne complexes and the polyelectrolytes.
Plasma Oxidized Polyhydroxymethylsiloxane—A New Smooth Surface for Supported Lipid Bilayer Formation
C. Satriano*†, M. Edvardsson‡, G. Ohlsson‡, G. Wang, S. Svedhem‡ and B. Kasemo*‡
† Department of Chemical Sciences, Catania University, Viale A. Doria, 6, 95125 Catania, Italy
‡ Department of Applied Physics, Chalmers University of Technology, SE-412 96 Gteborg, Sweden
Langmuir, 2010, 26 (8), pp 5715–5725
DOI: 10.1021/la903826d
Publication Date (Web): February 19, 2010
Copyright © 2010 American Chemical Society
*Corresponding authors. csatriano@unict.it. Phone: (+39) 095 7385136. Fax: (+39) 095 580138. kasemo@chalmers.se. Phone: (+46) 31 7723370. Fax: (+46) 31 772 3134.
Abstract
A novel substrate for preparation of supported lipid bilayers (SLBs), smooth at the subnanometer scale and of variable thickness from ten to several hundred nanometers, was developed by surface oxidation of spin-coated poly(hydroxymethylsiloxane) (PHMS) films. The deposited polymeric thin films were modified by a combination of oxygen plasma and thermal treatment (PHMSox), in order to convert the outermost surface layer of the polymer film to a stable SiO2 film, suitable for SLB formation. The hydrophilic, SiO2-like surfaces were characterized by XPS, wetting angle, ellipsometry, and AFM. Lipid bilayers were formed on this surface using the well-known vesicle adsorption-rupture-fusion process, usually performed on glass or vapor-deposited SiO2. Reproducible formation of homogeneous SLBs of different compositions (POPC, DOEPC, and POPC/DOPS) was demonstrated on the new SiO2 surface by quartz crystal microbalance with dissipation (QCM-D), surface plasmon resonance (SPR), and optical reflectometry measurements. The SLB formation kinetics on the PHMSox-coated sensors showed very similar characteristics, for all investigated PHMS thicknesses, as on reference sensors coated with vapor-deposited SiO2. The good adhesive properties of the PHMS to gold allows for the preparation of thin PHMSox layers compatible with SPR. The much smaller roughness at the nanometer scale of the PHMSox surfaces, compared to standard vapor-deposited SiO2-coated sensors, makes them advantageous for AFM and optical experiments and promising for patterning. To benefit optical experiments with the PHMSox surfaces, it was also investigated how the PHMS film thickness influences the SPR and reflectometry responses upon SLB formation.

Technology will destroy our world

2009-07-02T20:22:00.000-07:00

Well this picture can be real in 20 years to comes.

If you see some 20-30 years old movies, those

thing that show on TV now is happening for real.

The best example is just look arround you. Now basically

all our thing are mobile and we could not imagine that

this thing can be achieve by us.

KSV Sigma 700

2009-06-23T00:32:00.000-07:00

Modern Surface Chemistry that meet the international standard set by ISO and ASTM

ISO 6889, 6295, 1409, 304, 4311, DIN 53914, 53993, ASTM D 1590, 1417, 1331 971,

EN 14370, JIS K2241, IEC 60422

Call- 016-6339009

Ring Re-Form

2009-06-23T00:23:00.000-07:00

LB System 2000

2009-06-22T21:35:00.000-07:00

Travel to Sweden

2009-06-22T01:59:00.000-07:00

Sigma 700

2009-06-22T00:48:00.001-07:00

Sigma 700 Surface/Interfacial tension instrument, Also able to do Contact Angle, Wetting, Powder, Single Fiber, CMC, SFE, Density & Etc. Call 016-6339009

LB System 2000

2009-06-21T20:54:00.000-07:00

Contact 016-6339009 for more information

Sigma 702

2009-06-21T20:47:00.001-07:00

Introduction

2009-06-17T01:55:00.000-07:00

THETA NEW PULSATING DROP MODULE FOR RHEOLOGY STUDIES

The PD-200 pulsating drop module for Theta optical tensiometer functions by oscillating drops with control of both frequency and amplitude as well as wave shape (sine, triangle, square, etc.). This enables quick and easy interfacial rheology, providing viscoelasticity information for surfactant applications. Together with OneAttension and an automatic liquid dispenser, the PD-200 enables automatic drop volume adjustement to compensate evaporation. Compared to the previous version, PD-200 no longer requires calibration and benefit from an improved integration to the software.