This Application Note describes the nature of the electrostatic potential near the surface of a particle, called the zeta potential. It explains how the zeta potential is determined by measuring the velocity of the particles in an electric field. It also explains how the charge on the particle surface affects properties of suspensions and emulsions.
This document describes the electrostatic potential near the surface of a particle, known as the zeta potential. It explains how this potential is determined by measuring the velocity of particles in an electric field and how the charge on the particle surface affects the properties of suspensions and emulsions.
The text details the charge distribution around particles and the measurement process using electrophoresis. It specifically mentions the Agilent 7020 ZetaProbe, noting its unique method of measuring particle motion in MHz electric fields via sound waves, contrasting it with standard optical techniques. The document concludes by stating that a zeta potential magnitude greater than 25 mV is generally required to maintain a stable, dispersed system.
The zeta potential will usually need to be kept above 25 mV in magnitude to keep the system in a disperse state.
It measures particle motion by measuring the sound waves that the particles emit as they shake back and forth in MHz electric fields.