TANDEM IONISATION FOR GC(×GC)-MS: COMPLEMENTARY SOFT ELECTRON IONISATION FOR INCREASED CONFIDENCE IN COMPOUND IDENTIFICATION

摘要

Electron ionisation (EI) at 70 eV is standard practice for GC-MS, due to the high degree of ionisation (and thus good sensitivity) and consistent mass spectra generated. Nevertheless, the identification of individual compounds in complex samples remains challenging when multiple compounds in a chemical class have similar spectra, or weak molecular ions at 70 eV EI. This problem can be addressed by the use of soft ionisation to reduce the degree of ion fragmentation, but this approach has been cumbersome to implement until now.