Application of sample displacement batch chromatography for
fractionation of proteoforms
Abstract
Fractionation of proteoforms is currently the most challenging topic in
the field of protein purification. The need for considering the
existence of proteoforms into experimental approaches is not only
important in Life Science research in general but especially in the
manufacturing of therapeutic proteins (TPs) like recombinant therapeutic
antibodies (mAbs). Some of the proteoforms of TPs have significantly
decreased actions or even cause side effects. The identification and
removal of proteoforms differing from the main species, having the
desired action, is challenging because the difference in the composition
of atoms often is very small and their concentration in comparison to
the main proteoform can be small. In this study we demonstrate that
sample displacement batch chromatography (SDBC) is an easy to handle,
economic and efficient method for fractionating proteoforms. As a model
sample a commercial ovalbumin fraction was used, containing many
ovalbumin proteoforms. The most promising parameters for the SDBC were
determined by a screening approach and applied for a 10-segment
fractionation of the ovalbumin with cation exchange chromatography
resin. Mass spectrometry of intact proteoforms was used for
characterizing the SDBC fractionation process. By SDBC a significant
separation of different proteoforms was obtained.