Probe Electrospray Ionization

Abstract

Probe electrospray ionization (PESI) is an electrospray-based atmospheric-pressure surface sampling and ionization technique for mass spectrometry that uses a solid needle instead of a capillary. While ionization occurs in a fashion similar to that involved in electrospray ionization, the novel aspect of PESI is discontinuous sampling. The needle is driven up and down along the vertical axis to the apex of the ion-sampling orifice. At the highest position, the liquid trapped at the needle tip is electrosprayed. PESI is applicable to analyze the biological samples, imaging, real-time reaction monitoring, etc. The most unique feature of PESI is the sequential and exhaustive ionization of the analytes that cannot be accomplished by the capillary-based electrospray.

Molecular ion formation on activated field emitters in atmospheric pressure field desorption mass spectrometry

“…The relationship of field desorption of ionic compounds and microscale variants of electrospray ionization, e.g., nanoESI and probe electrospray ionization (PESI), was pointed out in a book chapter on PESI [ 27 ].…”

“…Moreover, all ions described in this preceding work on APFD-MS were even-electron species, i.e., either the respective cations or anions of ionic liquids along with their corresponding cluster ions or protonated and deprotonated species formed from highly polar analytes [ 29 ]. In this work, a continuous transition from the FD process to the microscale ESI process had been discussed as in the aforementioned chapter on PESI [ 27 ].…”