Size Exclusion Chromatography with Multi Angle Light Scattering (SEC-MALS)

​Application: Protein characterisation (molecular mass, oligomerisation, complexes)

​Instrument: OmniSEC (Malvern)

​Location: VBC5, room 101

SEC-MALS is used to measure the weight-averaged molar mass of proteins (and other macromolecules) in solution, and can determine oligomeric state and sample polydispersity. Size-exclusion chromatography (SEC) separates molecules based on hydrodynamic volume, but is dependent on similarity to a set of reference standards for accurate mass determination and fails for elongated or sticky proteins. Multi-Angle Light static Scattering (MALS) is used to measure light scattering intensity accurately, which is proportional to the weight-averaged mass in solution. Combining SEC, MALS and concentration detectors in a SEC-MALS experiment allows for more accurate mass measurements that SEC or MALS alone.

By using two concentration detectors (RI and UV), the molar mass and weight-fraction of a biomolecular heterocomplex can be determined. This can be used to measure protein and modifier masses of integral membrane proteins in detergent micelles and of glycosylated proteins.  

Measurements are exclusively performed by ProTech staff upon request.
Data analysis training by ProTech staff is possible upon request.