Extractive electrospray ionization mass spectrometry-enhanced sensitivity using an ion funnel

Anal Chem. 2012 Feb 21;84(4):2076-80. doi: 10.1021/ac203022x. Epub 2012 Jan 30.

Abstract

Electrodynamic ion funnel interfaces for electrospray ionization (ESI) have shown to enhance the sensitivity of measurements by more than 2 orders of magnitude in the intermediate pressure region of the instrument (1-30 Torr). In this study, we use an ion funnel at ambient pressure to enhance the sensitivity of extractive electrospray ionization (EESI) by spraying directly into the ion funnel. EESI is a powerful ionization technique that is capable of handling complex matrixes that may contain dozens of compounds. Our results using atenolol, salbutamol, and cocaine as test compounds show that we can improve the limit of detection for these compounds by more than 3 orders of magnitude compared to standard EESI experiments.