Computer simulations of a new toroidal-cylindrical ion trap mass analyzer

A novel toroidal-cylindrical ion trap (TCIT) design is introduced based on a compact dual ion trap system that comprises an outer toroidal ion trap (T-trap) and an inner cylindrical ion trap (CIT). These two traps have specific but different functions that can improve the performance of tandem mass analysis operation.

The TCIT is studied by using a simulated mass spectrometer platform that is mainly based on SIMION modeling and extensive data processing. This platform combines different functions, such as simulation of ion motion and field calculations, as well as acquisition of a simulated mass spectrum.

The main steps of the MS operation, including the full scan process, the mass-selective ejection of the ions in the T-trap, and the capture of the injected precursor ions in the CIT, are realized using the abovementioned platform. In addition, the simulated design is optimized for improved mass analysis performance.

For the outer T-trap, when the outside surface of the inner cylindrical electrode is modified to include a circular arc with appropriate radius, the ion ejection efficiency that is directed into the CIT could be significantly enhanced. In the case of the inner CIT, the ion capture efficiency could be improved to more than 90% with geometry optimization. Copyright © 2016 John Wiley & Sons, Ltd.