Abstract: Biomolecular interaction analysis mass spectrometry(BIA/MS) is a very promising method applied in proteomics for the characterization of protein-protein interactions. BIA/MS is an approach combining the surface plasmon resonance(SPR) technology with mass spectrometry for the real-time analysis and identification of interaction molecules that interact specifically with a known immobilized ligand. In this study, by using the Biacore-X instrument, about 0.1 pmol β₂-microglobulin was immobilized on sensor chip, the interacting protein in solution was delivered to the biosensor chip surface. Then, a microrecovery method of the principle of “sandwich” structure was used to elute the bonding microglobulin protein from the sensor chip, and the protein identification was then achieved after tryptic digestion by matrix-assisted laser desorption/ionization-time of flight mass fingerprint mapping and data-base search. The strategy was successfully applied to the model protein microglobulin interacting with its antibody, a unambiguous identification was obtained at 10^-15 mol level.

Key words: BIA/MS, Surface plasmon resonance(SPR), Biosensor chip, Proteomics