Updated project metadata. The goal of the project is development of an online two dimensional reverse phase/reverse phase liquid chromatography (2D-RP/RPLC) separation platform, employing an online non-contiguous fractionating and concatenating device (NCFC fractionator) in order to provide highly improve separation orthogonality of the two RPs, resulting in significant increase in peptide identification sensitivity compared with those of the conventional contiguous 2D-RP/RPLC method.