Development of a tandem time-of-flight mass spectrometer “MULTUM-TOF/TOF” at Osaka University: Combination of a multi-turn time-of-flight mass spectrometer and a quadratic-field ion mirror

A new multi-turn tandem time-of-flight (TOF) mass spectrometer'MULTUM-TOF/TOF' has been designed and constructed.It consists of a MALDI ion source, a multi-turn TOF mass spectrometer, a collision cell and a quadratic-filed ion mirror.The multiturn TOF mass spectrometer can overcome the problem of precursor ion selection in TOF due to insufficient time separation between two adjacent TOF peaks by increasing the number of cycles and as a result increasing the total time-of-flight.The quadratic-field ion mirror allows temporal focusing for fragment ions with different kinetic energies.Tandem mass spectra of angiotensin I have been obtained.The fragmentions mainly observed are a result of high-energy collision induced dissociation (CID).