Danyel Biotech Ltd 2 articles published in JoVE Biochemistry Characterization of Proteins by Size-Exclusion Chromatography Coupled to Multi-Angle Light Scattering (SEC-MALS) Daniel Some1, Hadar Amartely2, Ayala Tsadok3, Mario Lebendiker2 1Wyatt Technology Corporation, 2Wolfson Centre for Applied Structural Biology, The Alexander Silberman Institute of Life Science, The Hebrew University of Jerusalem, 3Danyel Biotech Ltd. This protocol describes the combination of size exclusion chromatography with multi-angle light scattering (SEC-MALS) for absolute characterization of proteins and complexes in solution. SEC-MALS determines the molecular weight and size of pure proteins, native oligomers, heterocomplexes and modified proteins such as glycoproteins. Biochemistry Ion Exchange Chromatography (IEX) Coupled to Multi-angle Light Scattering (MALS) for Protein Separation and Characterization Hadar Amartely1, Daniel Some2, Ayala Tsadok3, Mario Lebendiker1 1Wolfson Centre for Applied Structural Biology, The Alexander Silberman Institute of Life Science, The Hebrew University of Jerusalem, 2Wyatt Technology Corporation, 3Danyel Biotech Ltd This protocol describes the use of high-specificity ion-exchange chromatography with multi-angle light scattering for an accurate molar mass determination of proteins, protein complexes, and peptides in a heterogeneous sample. This method is valuable for quality assessment, as well as for the characterization of native oligomers, charge variants, and mixed-protein samples.