Use of TOFSim, a LabView-Based Time-of-Flight Mass Spectrometer Simulation, to Model Real Instrument Data.

It is demonstrated here that a recently published LabView-based time-of-flight mass spectrometer (TOFMS) simulation program (named TOFSim) can accurately simulate data collected on a commercial Bruker Autoflex III matrix-assisted laser desorption/ionization (MALDI) TOFMS instrument operating in linear mode. Once the instrument distances are determined by matching measured and simulated flight times, it is shown that both overall flight times and peak widths are reproduced for data collected under both focused and slightly defocused conditions. This work confirms that TOFSim can be used not just for training new instrument operators in the principles of TOFMS but, as demonstrated here, to show how changing the voltage applied to grid G1 in the source or the delayed extraction delay time affects the focusing properties of the instrument. In the future we expect that this will also allow users to perform "what-if" experiments to investigate scenarios which may be difficult or impossible to do in a real instrument.