Multi-angle light scattering (MALS)


At SOLVE we use the MALS detector (18-angles) almost exclusively connected on-line to SEC and AF4 for monitoring the eluted fractions. The MALS detectors we use are from Wyatt Technology.


Multi-angle light scattering (MALS) is a detection technique used to characterize macromolecules and particles in solution. The methodology is based on that the scattering of light from solutions containing macromolecules or particles depend on the macromolecules molecular weight and size among others.


MALS is a method applicable to a very wide range of compounds, such as proteins, nanoparticles, viruses, and polymers. MALS is applicable to compounds with molecular weight of ~ 1 000 g/mol and upwards, to sizes of approximately 500 nm. The MALS detector is typically used connected on-line to SEC or AF4 instruments to measure the molar mass and size of the eluted compounds.


  • Molar mass information without standards
  • High sensitivity for high molar mass components and aggregates
  • Excellent for troubleshooting SEC and AF4


  • Specialized and expensive equipment
  • Sensitivity to particulate impurities
  • Require some experience to operate and for data evaluation
  • Poor sensitivity for low molar mass components