Fast and high-resolution fractionation of positional isomers of a PEGylated protein using membrane chromatography

The fractionation of positional isomers of a PEGylated protein is quite challenging as these have similar molecular weight, and only very slightly different surface charge. In this study, cation exchange z² laterally-fed membrane chromatography (z²LFMC), which has been shown to be suitable for high-speed, high-resolution protein purification, was used to fractionate positional isomers of mono-PEGylated lysozyme. The performance of the z²LFMC …