Title

ESI outcompetes other ion sources in LC/MS trace analysis.

Authors

Laaniste, Asko; Leito, Ivo; Kruve, Anneli

Abstract

Choosing an appropriate ion source is a crucial step in liquid chromatography mass spectrometry (LC/MS) method development. In this paper, we compare four ion sources for LC/MS analysis of 40 pesticides in tomato and garlic matrices. We compare electrospray ionisation (ESI) source, thermally focused/heated electrospray (HESI), atmospheric pressure photoionisation (APPI) source with and without dopant, and multimode source in ESI mode, atmospheric pressure chemical ionisation (APCI) mode, and combined mode using both ESI and APCI, i.e. altogether seven different ionisation modes. The lowest limits of detection (LoDs) were obtained by ESI and HESI. Widest linear ranges were observed with the conventional ESI source without heated nebuliser gas. In comparison to HESI, ESI source was significantly less affected by matrix effect. APPI ranked second (after ESI) by not being influenced by matrix effect; therefore, it would be a good alternative to ESI if low LoDs are not required.

Subjects

ION sources; TRACE analysis; MATRIX effect; ATMOSPHERIC pressure; MASS spectrometry; LIQUID chromatography-mass spectrometry

Publication

Analytical & Bioanalytical Chemistry, 2019, Vol 411, Issue 16, p3533

ISSN

1618-2642

Publication type

Academic Journal

DOI

10.1007/s00216-019-01832-z