Thereafter, these eluates were pooled, concentrated and depleted again with ProteoPrep20. Even this multi-step depletion approach did not allow the complete removal of high abundance proteins,GAT211 although the number of peptides belonging to these proteins was reduced. Moreover, despite the multi-depletion approach, the number of identified peptides and proteins, the average sequence coverage, and the sensitivity limit of the analysis were similar compared to those obtained after a single depletion with ProteoPrep20. A further attempt to improve the analyses, by analyzing again the same samples using the same parameters and chromatographic conditions, but applying an exclusion list resulted only in the increase of the percent coverage of some proteins already identified. This partly confirms that, to dig deeper into the plasma proteome, the most appropriate strategy of analysis is to include additional steps and separate proteins on the basis of many different criteria, such as the specific capture of glycol- and cysteinyl-peptides. While ProteoPrep20 kit was developed specifically for the plasma analysis, the ProteoMiner approach, even if it is a relatively recently developed technology, has already been applied to the study of proteome from urine, serum, platelets,LUF7346 and red blood cells. This novel fractionation method employs a large, highly diverse bead-based library of combinatorial peptide ligands, which simultaneously reduces HAPs and enriches LAPs. The recovery of proteins after LAPs enrichment is approximately 3%, which is the same recovery obtained after the ProteoPrep20 depletion. In terms of amount of proteins, however, ProteoMiner allows obtaining a quantity 150 times greater and this depends on the high capacities of the column. Although LAPs enrichment led to the identification of fewer proteins with respect to ProteoPrep20 depletion, we must take into account the great advantage of obtaining sufficient material that can still be subjected to further analysis.