Advancement of Traveling Wave Ion Mobility Spectrometry and Its Application

Ion mobility spectrometry (IMS) utilizes the difference in ion mobility K (collision cross section) to realize the separation and determination of different ions, which has the advantages of fast analysis speed and high sensitivity. And it coupling with mass spectrometry (IM-MS) was widely used in the fields of proteomics, metabolomics, medicine, etc. With the increasing complexity of the analyzed objects, higher demands are put on the resolution of the IMS. Traveling wave ion mobility spectrometry (TWIMS) uses a time-domain continuous traveling wave electric field to realize ion transport and separation. The analytical path length of the TWIMS is not limited by the amplitude of the travelling wave voltage, theoretically the path can be extended indefinitely to improve the resolution. Currently, the resolution of TWIMS can reach up to 1 860, which is advantageous for the analysis of complex samples with the multiple isomers. The principle of TWIMS and the influencing factors of resolution were introduced, the characteristics, performance and applications of TWIMS instruments with different structures were further discussed, and finally the future development directions of TWIMS were prospected.