The design of an atmospheric pressure ionization/time-of-flight mass spectrometer using a beam deflection method

Abstract
A novel time‐of‐flight (TOF) mass spectrometer configuration has been designed which can be interfaced to a continuous ion beam source produced by atmospheric pressure ionization. The TOF device uses a beam deflection method to sweep the ion beam past a slit placed near the ionization source in order to generate a start pulse for TOF detection. The beam sweep technique is modeled by computer simulation and optimized for the various experimental parameters. Nonvolatile samples are injected into the TOF device using liquid injection into a glow discharge atmospheric pressure ionization source in helium. A resolution of at least 519 at m/z 311 is obtained, which is limited by the experimental parameters available in our experiment. The mass resolution is computer modeled and it is shown that as the mass increases, the experimental constraints become less important, and the resolution will increase. It is predicted that using the correct experimental conditions and with the addition of an ion reflector that resolution of well over 1000 should be obtained.