Ion mobility separation coupled to high-resolution mass spectrometry in environmental analysis – Current state and future potential

The hyphenation of ion mobility separation (IMS) with high-resolution mass spectrometry (HRMS) presents a milestone in the screening of organic micropollutants (OMPs) in complex environmental matrices. Its use has become progressively more widespread in environmental analysis and has led to the development of novel analytical strategies. This work provides a comprehensive overview of the advantages of using IMS-HRMS instrumentation, with a special focus on environmental screening studies. IMS provides an additional parameter for OMP identification, a reduction of spectral background noise and the power to resolve isomeric/isobaric coeluting interferences. These advantages lead to a reduction of false positive identifications. By describing the fundamentals and rationale behind the observed advancements, we highlight areas for further development that will unlock new potential of IMS-HRMS. For example, an enhanced availability of empirical IMS data following the FAIR principles, a better standardization of IMS-HRMS data processing workflows and a higher IMS resolving power are possible ways to advance the use of IMS-HRMS instruments for the analysis of complex environmental samples.