Dynamic Light Scattering (DLS)

Size distributions without fractionation

Dynamic Light Scattering (DLS) measures the translational diffusion coefficients Dt of nanoparticles and colloids in solution by quantifying dynamic fluctuations in scattered light. Sizes and size distributions, in turn, are calculated from the diffusion coefficients in terms of hydrodynamic radius Rh or hydrodynamic diameter dh.DLS is suitable for ensemble measurements ranging from Rh values of 0.2 nm up to 5,000 nm. Wyatt offers high-throughput, automated DLS as well as conventional, cuvette-based formats.

Applications of DLS

Here are just a few of the diverse applications supported by DLS:

  • Estimate populations of aggregates large and small, for small molecules, proteins or liposomes
  • Check quality of biomolecules prior to running costly analyses such as SPR or SANS
  • Analyze thermal stability and chemical denaturation, differentiating pure unfolding from aggregation
  • Measure size and concentration of viruses and VLPs
  • Quantify self-assembly processes of polypeptides or DNA
  • Assess colloidal stability as a precursor to aggregation and precipitation
  • Measure viscosity of concentrated biotherapeutics with just a few microliters of solution
DLS analysis showing a protein monomer mixed with 50 nm particulates. The size resolution of unfractionated solutions is a factor of 3-5x in radius.
DLS determines size distributions without fractionation, providing polydispersity estimates as well as hydrodynamic radii.