Dynamic light scattering (DLS), sometimes referred to as Quasi-Elastic Light Scattering (QELS), is a non-invasive, well-established technique for measuring the size and size distribution of molecules and particles typically in the submicron region, and with the latest technology lower than 1nm.

Typical applications of dynamic light scattering are the characterization of particles, emulsions or molecules, which have been dispersed or dissolved in a liquid. The Brownian motion of particles or molecules in suspension causes laser light to be scattered at different intensities. Analysis of these intensity fluctuations yields the velocity of the Brownian motion and hence the particle size using the Stokes-Einstein relationship.

Dynamic light scattering technology from Malvern Instruments offers the following advantages:

  • Accurate, reliable and repeatable particle size analysis in one or two minutes.
  • Measurement in the native environment of the material.
  • Mean size only requires knowledge of the viscosity of the liquid.
  • Simple or no sample preparation, high concentration, turbid samples can be measured directly.
  • Simple set up and fully automated measurement.
  • Size measurement of sizes < 1nm.
  • Size measurement of molecules with MW < 1000Da.
  • Low volume requirement (as little as 2µL).
  • Compliance with regulatory standards ISO 13321, ISO 22412, 21 CFR Part 11.