Dynamic Light Scattering (DLS) allows the hydrodynamic size of particles in dispersion to be measured by quantifying their diffusive motion.
At particle sizes approaching the upper size range for DLS, sedimentation, thermal currents and number fluctuations can mean that the detected scattering no longer accurately describes purely diffusive motion, and particle size analysis becomes less accurate.
This can be seen in measurements of monodispersed samples that exhibit
artefacts in the correlation function baseline. This may be mitigated by
adjusting dispersant, either density or viscosity, however both offer a less than
ideal remedy as we are no longer measuring the original system of interest.
Download this free white paper to find out more.