Polyethylene glycol (PEG) strands are conjugated to therapeutic proteins to increase the half-life of the protein in the bloodstream and make it less likely to be hydrolyzed. Since PEGylated proteins have a very different conformation and hydrodynamic size-molar mass relationship than globular proteins or linear polymers, they cannot be analyzed by standard analytical SEC using column calibration. In this application note we demonstrate the information that can be obtained on the results of a PEGylation process by combining sizeexclusion chromatography with multi-angle light scattering (SEC-MALS) to analyze conjugation.

null
Download PDF
microDAWN®

microDAWN®

The microDAWN MALS detector performs absolute characterization of macromolecules eluting from UHPLC, determining molar mass and size independently of retention time and molecular reference standards.

This instrument offers superb sensitivity over a wide range of molar mass, size and concentrations. In most respects the microDAWN is similar to the well-established miniDAWN , a workhorse MALS instrument used in hundreds of labs around the world for characterizing proteins and other molecules smaller than 50 nm in radius.

Read more
microOptilab

microOptilab

Universal Detection for UHPLC and SEC-MALS

Refractive index detection is an important component of any SEC-MALS system, and necessary for analyzing conjugated proteins or polymers devoid of chromaphores. The microOptilab connects with the microDAWN MALS detector for a complete UHP-SEC-MALS setup that transfers the many benefits of SEC-MALS analysis to the realm of UHPLC.

Read more