DT310 – Zeta potential and Titration

Zeta potential probe with 2 burettes titration

This instrument measures zeta potential of concentrated dispersions and emulsion. Consequently, it is similar to the model DT-300. However, in addition it allows conducting titration due to 2 burettes. Consequently, it provides data on iso-electric point, surfactant optimum doze, sample kinetics changes. This instrument can be supplied with conductivity probe when samples are aqueous solutions. Temperature probe and pH probe are standard options of this model.

This Zeta potential instrument requires mixing capability for the sample since added chemicals should be properly spread throughout the sample. Peristaltic pump is one of the possible means for organizing such mixing, especially when samples are rather viscous. Alternatively, magnetic mixer allows achieving the same goal for low viscosity samples. Hoto above demonstrates such setup.

Windows based software contains database of materials which simplifies sample definition. It allows creation of standard operating procedures when the same sample is measured routinely for quality control. The same database stores all measurements results automatically after measurement finished.

Advantages over micro-electrophoresis and ELS:

• no dilution when volume fraction up to 50%
• less sensitive to contamination due to lack of dilution
• higher precision (± 0.1 mV)
• low charges (down to 0.1 mV)
• electro-osmotic flow negligible
• convection is not important
• accurate for non-aqueous dispersions when dielectric constant is low