Tracker™ - the only surface and interfacial tensiometer you will ever need

All relevant and vital surface & interfacial parameters you need in one simple, intelligent analytical package

Interfaces are fascinating and control most natural and industrial processes and reactions. While some interfaces are simple, most are dynamic and complex.

To correctly understand the behavior of surfaces and interfaces, any analysis tool must meet the challenge of accurately analyzing all pertinent aspects of the interface and surface characteristics under various environmental conditions.

Surface and interfacial tension analysis (tensiometry) can be grouped into

1) pure liquid analysis and

2) liquids containing surface active materials analysis.

If you only work with pure liquids, you have many choices and can analyze the surface and interfacial tension via older methods such as the Wilhelmy plate technique, du Noüy ring method, falling drop, and capillary tube apparatus.

Since virtually all natural and industrial environments and products contain some surface-active materials, your choices are more limited. If your goal is to understand and measure surface and interface properties correctly, the aforementioned older techniques do not work.

We built our Tracker™ tensiometer platform around an advanced optical technique using axisymmetric drop shape analysis (i.e., pendant drop, sessile drop).

The advantage for you is that you can use the method to analyze all surface and interfacial tension phenomena.

You can work with pure liquids and with liquids containing surface active ingredients.

You can measure both static and dynamic events.

And you can do so accurately under different environmental conditions.

“The drop shape method is an absolute measurement of surface and interfacial tension.”

— Surface Chemistry of Solid and Liquid Interfaces, Professor H. Y. Erbil, Blackwell Publishing, 2006

We designed the Tracker™ to be the most comprehensive tensiometer available.

Yet we wanted it also to have a modular design because not everyone needs or wants to analyze all surface and interfacial properties.

The Tracker allows you to measure one, a couple, or all relevant surface and interface properties under wide-ranging environmental conditions. All with one instrument.

As your needs and application field grows, you can always add additional modules.

With the Tracker™, you have the freedom of choice.

Surface and interfacial tension dynamics

Measure all relevant surface and interfacial properties

The Tracker™ modular design gives you the freedom and flexibility to invest in only those analytical modules that are important to your work. Measure:

Interfacial tension (liquid/liquid)
Surface tension (liquid-gas)
Adsorption/desorption kinetics
Interfacial Dilatational Rheology
Viscoelastic modulus
Coefficient of rigidity
Critical micelle concentration CMC
LaPlace pressure inside a bubble
Tensiometry at elevated pressures and temperatures

Critical micelle concentration (CMC)

Surfactants contain hydrophilic and hydrophobic parts. Due to this amphiphilic nature, surfactants can form spontaneous structures referred to as association or self-assembled colloids.

The simplest forms of association colloids are micelles. They are dynamic self-forming structures with various shapes (spherical, lamellar, disk, and cylindrical shaped) and sizes.

The most common and valuable measurement to understand micelles is the concentration at which micelles form spontaneously; the critical micelles concentration (CMC).

The Tracker™ intelligent CMC module automatically determines the critical micelle concentration using up to four different surfactant solutions. The injected volume and concentration are determined by an algorithm that calculates the concentration steps and volume amount to optimize the accuracy of the CMC determination.

The Tracker™ intelligent CMC module gives you extraordinary sensitivity and flexibility to understand complex surfactant interactions and micelle formations.

Phase Exchange Module

You can study the effects of solution chemistry and composition changes on the surface or interfacial layer inside or outside the formed bubble/droplet.

This phase exchange method is potent as it allows you to measure the sequential adsorption of different components at a liquid/liquid interface, in addition to the classic simultaneous adsorption measurement from a mixed solution.

Thus, for example, the movement of pre-adsorbed proteins after the successive addition of another surfactant can be successfully studied by this technique.

Measuring surfactant interface adsorption and desorption kinetics

Interfacial Rheology

Interfaces are dynamic entities. When working with solutions containing different or a mixture of surfactants, polymers, proteins, lipids, and particles, understanding the adsorption-desorption kinetics and surface/interface equilibrium arrangement is essential.

Calculating the viscoelastic modulus also allows you to deduce interfacial elasticity and viscosity effects on foam and emulsion stability.

With the Tracker™, you can control the drop/bubble volume and perform high-frequency sinusoidal variations with industry-leading precision giving you exceptionally accurate and repeatable viscoelasticity and rigidity data (for membrane-type interfaces and surfaces).

Surface Pressure

You can also control and measure the surface pressure using the Tracker.

Specific or custom-made interfaces can be made to mimic different interfacial systems and to study rheological properties at different interfacial pressures.

Thus, it is possible to determine the building blocks of an interface, study the adsorption of one or several molecules sequentially added, or determine the exclusion pressure of molecules.

It is a powerful and unique tool to study membranes like surfaces (e.g., lipid membranes)

Solid-liquid interfaces

In addition to all the surface and interfacial measurement capabilities, the Tracker™ also allows you to measure all relevant material surface properties of solids surfaces using the well-known sessile drop method (static and dynamic).

Measure static and dynamic (advancing and receding) contact angles in both ambient and under extreme temperatures and pressures.

Elevated Temperature and Pressure Module

Perform surface and interface/interfacial analysis at elevated temperatures and pressures up to 120 C (248 Fahrenheit)and 8 bars (116 psi) using the medium temperature and medium pressure module.

For ease of use, the syringe piston is accessible from outside the cell and can be automatically controlled. The cell pressure is controlled via the gas control box, which can be connected to any in-house pressure setup, gas cylinder, or compressor.

You can make multiple contact angle measurements without opening the high-pressure cell. This is due to the unique design of the pressure cell, which allows you to place several drops on or under a solid and then perform the contact angle measurement.

A separate thermocouple measures the temperature of the liquid inside the cell and is regulated via a dedicated temperature control box.