Zetasizer Pro

The Zetasizer Pro is an instrument to perform measurement of particle size, molecular size, electrophoretic mobility, zeta potential and molecular weight in the liquid solutions. The Dynamic Light Scattering (DLS) mode can be used to measure particle and molecule size, from 0.3 nm to 10 µm. Electrophoretic Light Scattering (ELS), which measures the zeta potential of particles and molecules, can be used to indicate sample stability and/or propensity to aggregate.  The Non-Invasive Back Scatter (NIBS) offers possibility to use these optics for versatile, high sensitivity, particle and molecular size measurements and molecular weight measurements. M3-PALS with constant current mode is used for zeta potential and electrophoretic mobility measurements. ZS Xplorer software suite offers a simple and flexible method set-up and data analysis. The software is also equipped with Adaptive Correlation function for faster, more reproducible sizing measurements with less sample preparation. The optical filter wheel with fluorescence filter allows measurement of fluorescent samples without impairing overall system sensitivity. It is suitable for routine sample investigation such as metallic colloids, metal oxides and pigments. The accessory of MPT-3 Autotitrator enables study of the effect of changes in pH. A range of disposable and reusable cells are available to optimize the measurement in terms of sample volume and concentration.

MPT-3 Autotitrator

pH is one of the main influences on the zeta potential of materials. Understanding how the samples behave over a range of pH conditions is important in determining when they are most, or least, electrostatically stable, or even if their particle size will change (for instance, by agglomeration or dispersion) over a specific pH range. 

The MPT-3 Autotitrator incorporates a pump to carry the sample from the reaction vessel to the Zetasizer, pH probe and measurement electronics, and three syringes for three titrants. The syringes have low volume displacement and well-characterized plunger diameters. This allows the accurate addition of very small amounts of titrant, as low as 0.28 µL, which enables precise targeting of the desired pH value. This is particularly important at pH values close to neutrality. The Autotitrator supports the use of two concentrations of acid or base in order to generate a very wide pH range. The system will automatically use the appropriate titrant to provide the minimum amount of additive with the maximum accuracy. Use of a degasser for titrants is recommended to prevent air-locks forming in the titrant lines.