Zetasizer Nano ZSP

The Zetasizer Nano ZSP is the premium system in the Zetasizer range. It is used for the measurement of size, electrophoretic mobility of proteins, zeta potential of nanoparticles and surfaces, and optionally the microrheology of protein and polymer solutions.

The exceptional performance also enables the measurement of the molecular weight and second virial coefficient, A2, of macromolecules and kD, the DLS interaction parameter.

The system can also be used in a flow configuration to operate as a size detector for Size Exclusion Chromatography (SEC) or Field Flow Fractionation (FFF).

The Zetasizer Nano ZSP is the world’s highest performance system and particularly suitable for the characterization of proteins and nanoparticles where the highest sensitivity for size and zeta potential measurement is required. It includes a Protein Measurement option for protein mobility measurements.

The system incorporates a two angle particle and molecular size analyzer for the enhanced detection of aggregates and measurement of small or dilute samples, and samples at very low or high concentration using dynamic light scattering with ‘NIBS’ optics. The ZSP also incorporates a zeta potential analyzer that uses electrophoretic light scattering for particles, molecules and surfaces, and a molecular weight analyzer using static light scattering.

Using Non-Invasive Backscatter optics (NIBS) it has significantly better performance than systems using 90 degree scattering optics.

In addition, a microrheology option is available for measuring sample viscosity and viscoelastic properties.

The flow mode option enables the system to be connected to an SEC or an FFF system to use as a detector for the size of proteins or nanoparticles.

A choice of cuvettes are available, from disposable single-use to specific cells for viscous or high concentration samples or measuring the zeta potential of surfaces.

Parameters measured:
Particle and molecule size, translational diffusion, electrophoretic mobility, zeta potential of particles at high and low concentrations, viscosity and viscoelasticity of protein and polymer solutions, concentration, MW, A2, kD.

An optional accessory enables measurement of the zeta potential of solid surfaces.


The MPT-2 is an accessory for the Zetasizer Nano that provides extensive automation for a number of measurements that are routinely required when characterizing the size and zeta potential of dispersed particles and molecules.

Both the size and zeta potential can be measured in sequence as part of the automated titration.

pH is one of the main influences of the zeta potential of materials, so measuring zeta potential as a function of pH, and the determination of the isoelectric point are often required. Automating this improves productivity by proving a complete measurement using a stored method.

Conductivity is also measured, and automation can speed up the determination of whether ions in a formulation are specifically or non-specifically bound.

The same automation can be extended to study the effect of the concentration of additives such as surfactants and polyelectrolytes, and there is a dilution function to study the effect of dilution on the size and zeta potential of the sample.

The Zetasizer NanoSampler can accommodate up to 96 sample vials, accurately delivering up to 3 sequential aliquots of each sample into the Zetasizer Nano for automated particle size or molecular size measurements. All operation remains within the easy-to-use Zetasizer software using the simple Standard Operating Procedure (SOP) interface. The NanoSampler is delivered complete with the software, analysis cell and fittings to attach to the Zetasizer Nano instrument.