Surface plasmon resonance is widely used to study binding interactions with proteins, potentially yielding information on kinetics, thermodynamics and active concentrations. However, the technology cannot identify the involved interaction partners. Mass spectrometry, on the other hand, can be used for specific identification of proteins in amounts comparable to the levels that can be captured on a Biacore SPR sensorchip. Here we present protocols for capturing, washing and eluting proteins from Biacore instruments as well as for robust sample preparation for sensitive mass spectrometric identification.
