Passive elution of proteoforms from polyacrylamide gels combined with anion exchange purification for in-depth top-down analysis of the human low molecular weight proteome.

We developed a novel sample preparation method by combining Passively Eluting Proteins from Polyacrylamide gels as Intact species for MS (PEPPI-MS) fractionation with Anion-Exchange disc-assisted Sequential sample Preparation (AnExSP) purification, and evaluated its performance in TDP analysis by comparing it with a conventional PEPPI workflow using Methanol-Chloroform-Water (MCW) precipitation.