“…During stepwise solubilization, plasma membranes are frozen and thawed, and subsequently treated with salts, usually at higher pH, followed by chaotropic reagents, and then by different ionic or non-ionic detergents, or by combination of these substances [5, 8, 12]. We used this solubilization schema for qualitative and semi-quantitative comparison of proteomes of tissues and for identification of candidate biomarkers for hepatocellular carcinomas [13, 15]. Peng’s group recommended the use of a similar method for enrichment of membranes from the liver microsomal fraction, to be followed by SDS-PAGE, tryptic digestion of excised proteins and identification by LC-MS/MS [15].…”