P200 ScreenTape can suppress antibody reduction artifacts under non-reducing conditions, providing a more accurate, precise and convenient method for mAb analysis
This document provides a technical overview regarding the analysis of monoclonal antibodies (mAbs). It addresses the issue where certain IgG subtypes exhibit higher than expected half-antibody representation under denaturing, non-reducing conditions due to cryptic cysteins exposed by dodecyl sulfate.
The text details an experiment using N-ethylmaleimide (NEM) prior to SDS-PAGE analysis. The results show that treating labile IgGs with NEM reduces the formation of these denaturing artifacts on P200 ScreenTape under non-reducing conditions, offering a more accurate method for mAb quantification compared to traditional methods.
Treatment with N-ethylmaleimide (NEM) prior to SDS-PAGE analysis reduces the appearance of half antibodies by alkylating free cystein residues, preventing auto-reduction.
The reactions should be carried out at a neutral pH because elevated pH can cause NEM to react with lysine residues and produce unexpected results.