Date recorded: October 21 2020

ZetaClass is a comprehensive webinar series on dynamic and electrophoretic light scattering where our experts walk you through the basic measuring principles, data interpretation and tests performed to gauge data quality. Whether you are a new or advanced user of light scattering solutions, we will answer all your questions.

Nanoparticles provide crucial functionality across a wide range of materials, applications and sectors. Dynamic light scattering analysis, together with zeta potential information, allows us to confidently measure the size distribution profiles of particles in the sub-micron range as well as assess the behavior of these nanoparticles in suspensions.


Zeta potential is a physical property which is exhibited by any particle in suspension. When an electric field is applied across an electrolytic solution, charged particles suspended in the electrolyte are attracted towards the electrode of the opposite charge. Viscous forces acting on the particles tend to oppose this movement.

The zeta potential is the electrostatic potential at the particle slipping plane, which is the outer boundary within which all ions diffuse with the particle. It is calculated from the mobility measured during an electrophoretic light scattering (ELS) experiment. It can be used to optimize the formulations of suspensions and emulsions. Knowledge of the zeta potential can reduce the time needed to produce trial formulations. It is also an aid in predicting long-term stability.

The Zetasizer Advance Series uses a combination of laser Doppler velocimetry and phase analysis light scattering (PALS) in a patented technique called M3-PALS to measure particle electrophoretic mobility. Implementation of M3-PALS enables even samples of very low mobility to be analyzed and their mobility distributions calculated. When establishing the level of confidence in the zeta potential results derived from an electrophoretic light scattering measurement, users should always first consider the repeatability of the measurement, i.e. how repeatable is the result derived from sequential measurements of the same sample aliquot.

The quality of data obtained from an electrophoretic light scattering (ELS) measurement is paramount to the reliability of the result obtained. However, in electrophoretic light scattering, there is no single parameter that can be used to gauge the quality or “goodness” of a measurement data set, but rather a collection of measurement parameters that need to be examined prior to attaching a large degree of confidence to an ELS derived zeta potential distribution.

This webinar discusses the parameters a user should consider to assess the quality of the measurement data obtained. This session is led by Dr Anand Tadas, Malvern Panalytical's regional application specialist who has a wealth of knowledge in biologicals and DLS. 

Interested to improve your R and D / manufacturing process and gain more knowledge about the applications of particle size distribution using DLS? Scroll down to register your interest in our series of webinars.

Join our free ZetaClass series

- ZetaClass 1: The best Dynamic Light Scattering (DLS) system for your particle characterization requirements. More info

- ZetaClass 2: Dynamic Light Scattering (DLS) data interpretation and troubleshooting. More info

- ZetaClass 3: Electrophoretic Light Scattering (ELS) for Zeta potential measurements​. More info

- ZetaClass 4: Applications of Zetasizer series across different sectors of the industry​. More info