Assessment of the reproducibility of random hexapeptide peptide library-based protein normalization.

The wide dynamic range of proteins in biological samples poses a challenge for the detection of low-abundance proteins. Recently, combinatorial hexapeptide peptide libraries have been suggested as an approach to normalization of proteins in such mixtures. We examined the reproducibility of a commercial hexapeptide ligand library for quantitative and comparative serum proteomic analysis. We also compared this technology with IgY-based affinity depletion.