Monodisperse polystyrene based micro particles (size: 0.5 μm) are a particle size standard, designed to profile the particle size distribution (PSD) of test samples.

Used to calibrate, qualify and monitor the performance of particle size analyzers, surface scanning instruments and particle counters.
Monodisperse polystyrene latex particles are also used to find the PSD of colloidal dispersions.

For every lot exact values of particle size and standard deviation are determined with an accuracy of 0.001 μm. The size determination of these particles follows procedures described by National Institute of Standards and Technology (NIST, USA) respectively by the Community Bureau of Reference (BCR), esp.:

• Transmission electron microscopy (TEM)
• Scanning electron microscope
• Light microscopy
• Coulter^™ counter with MDF-system

Calibration of equipment is carried out with NIST-respectively BCR-particle size standards.

Coulter is a trademark of Beckman Coulter, Inc.