Method of multi-reflecting timeof flight mass spectrometry with spectral peaks arranged in order of ion ejection from the mass spectrometer

Abstract

A multi reflection time of flight (MRTOF) mass spectrometer () And method for identifying a sample is disclosed. Sample ions are generated at an ion source (). The MRTOF is a closed mirror arrangement with first and second opposed ion mirrors (') on an axis of reflection (XX′). The MRTOF () also includes a bidirectional ion deflector () on that axis (XX′). The deflector () deflects ions onto the reflection axis as a short pulse at time to <zero> where they oscillate multiple times, separating in time of flight according to ion m/z. At a later time t, ions travelling in both directions along the axis (XX′) are ejected out of the MRTOF () by the bidirectional deflector () to an ion detector arrangement (). The separation of ions in time of flight allows a 'fingerprint' of a biological sample to be produced by the detector arrangement () without the need to assign a mass to each peak. Comparison with a library of fingerprints permits identification.