The study of electrochemistry with ambient mass spectrometry

•Coupling electrochemistry with ambient ionization mass spectrometry.•Coupling interfaces include liquid-sample desorption electrospray ionization (DESI).•Coupling interfaces include nanospray DESI.•Coupling interfaces include flowing atmospheric pressure afterglow (FAPA).•Interesting utilities with the focus on disulfide proteomics analysis.

Ambient ionization methods, which can be used to ionize samples directly with no or little preparation under ambient conditions, are a new generation of ionization technologies for mass spectrometry (MS). In this article, we review the coupling of electrochemistry (EC) and MS using ambient ionization methods, such as liquid-sample desorption electrospray ionization (DESI), nanospray DESI and flowing atmospheric pressure afterglow (FAPA). With these novel coupling interfaces, unique applications could be realized, such as online reduction and analysis of disulfide bond-containing proteins and peptides, and investigation of electrochemical reactions on electrode surfaces.