Biotherapeutics such as monoclonal antibody-derived molecules as well as their impurity profiles are becoming more complex. That challenges the routinely applied analysis of high- and low-molecular weight impurities by size exclusion chromatography and UV-absorbance. Possible limitations of SEC-UV can be overcome by adding advanced detection technologies such as multiangle light scattering (MALS) and mass spectrometry (MS). This podcast will explain the different detection methods and the results they deliver. Special emphasis will be placed on the higher requirements for size exclusion columns and methods preceding advanced detection methods.