To provide a retentate chromatography method for separating analytes in a sample.

The retentate chromatography method includes a process for adsorbing analytes in a substrate under a plurality of different selection conditions and a process for detecting the analytes held in the substrate by desorption spectrometry. The analytes are purified by this and conditions useful for the detection of the analytes are identified. The substrate having an adsorbent is used as specific detector of a plurality of analytes. Impurities are removed by exposing analytes containing impurities to the adsorbent, and the analytes are collected from the adsorbent in a subsequent round. The retentate chromatography method is useful for biology and medicine including clinical diagnosis and chemical discovery.