Dr. Stepan Podzimek discusses the limitations of size-exclusion chromatography and how they can be solved using multi-angle light scattering and asymmetric-flow field-flow fractionation.
Size-exclusion chromatography (SEC), also known as gel-permeation chromatography (GPC), has become the dominant technique for the determination of molar mass distributions of synthetic and natural polymers. The method is relatively simple and easy to use. However, limitations of this technique may lead to results that are not only incorrect, but even completely misleading.
The principal limitations of SEC are: 1) lack of appropriate column calibration standards; 2) non-ideal separation due to column interactions beyond purely steric; and 3) shear degradation of HMW fractions. These limitations can revealed—and often solved—by incorporating a multi-angle light scattering (MALS) detector following the SEC separation. Shear degradation and most of the non-steric effects can be eliminated by applying an alternative separation technique, asymmetric-flow field-flow fractionation (AF4).
Key Topics Include:
- Separation principles of SEC and AF4
- Non-steric separation mechanisms
- Why SEC with column calibration often provides incorrect molar mass distributions
- Theory and instrumentation of multi-angle light scattering
Who Should Attend?
The webinar is intended for all scientists interested in detailed characterization of synthetic and natural polymers, especially SEC users and those who are interested in learning about an alternative separation technique offering advantages over SEC.