Hyphenation of electrochemistry with mass spectrometry for bioanalytical studies

Hyphenation of electrochemistry (EC) and mass spectrometry (MS) is a growing research field with particular importance for bioanalytical applications. It opens the way for studying reaction mechanisms and metabolic pathways of biological compounds and drugs. Electrochemical conversion of sample molecules prior to MS analysis gives rise to short-lived intermediates and products naturally occurring in biological systems, which leads to better understanding of physiological processes. Numerous interesting and attractive studies in this field have been published so far demonstrating potential of EC–MS coupling. The combination with separation system such as liquid chromatography or capillary electrophoresis widens the scope of application providing additional information about compounds of interest. The combination of EC with liquid chromatography has been the most frequently used hyphenated system due to the simplicity of coupling to mass spectrometric detection. In terms of bioanalytical applications capillary electrophoresis offers some advantages and is a complementary technique to liquid chromatography. This review summarizes recent developments in this field from both instrumental and application perspectives. A rather new approach of coupling electrochemistry–capillary electrophoresis–mass spectrometry and its potential for bioanalysis is presented.