  While prefractionation has previously been shown to improve results in MS
analysis, a novel combination provides an additional dimension of separation:
protein fractionation by SDS-PAGE followed by IEF of tryptic peptides before
separation by RP-LC [Atanassov and Urlaub, Proteomics 2013, 13, 2947-2955].
This three-step separation procedure prior to MS/MS substantially increases
proteome coverage and represents a further step toward a more comprehensive
analysis of complex proteomes.
