Advance in Structures for Lossless Ion Manipulations

The structures for lossless ion manipulations (SLIM) combined with electrostatic field, radio frequency electric field and ion-driven electric field enable manipulation of ions in the gas phase including trapping, selecting and accumulating efficiently without loss, which has significant potential to ion mass spectrometry-mass spectrometry ( IMS-MS ) analysis, mini-IMS, multi-level ion reaction and so forth. According to the type of ion-driven electric field, SLIM can be divided into direct current gradient (DC-SLIM) and travelling wave (TW-SLIM). DC-SLIM uses gradient voltage to drive ions, which is simple in structure, but with the increase of migration length, the applied potential is large and difficult to realize. TW-SLIM uses traveling wave to push ions in wave mode. The applied electric potential is periodic and moderate, and the ion manipulation is more flexible, so it is more popular at present. In this paper, the working principles of two types of SLIM are analyzed and the research progress of SLIM in recent years is summarized. Finally, the anticipated research directions of SLIM are given to the further development of SLIM including function, structure and application.