High sensitivity analysis of proteins and peptides by capillary electrophoresis‐tandem mass spectrometry: Recent developments in technology and applications

Abstract

Analytical biochemistry, in particular the analysis of regulatory proteins that control biological systems and pathways, is dependent on methods of ever‐increasing sensitivity. Capillary electrophoresis (CE) has long been recognized as an ultrasensitive analytical technique. In spite of the high sensitivity, CE has not penetrated protein discovery research as a standard analytical method. In this review article we summarize recent technical developments which have significantly enhanced CE as a tool for the analysis of trace amounts of proteins. Specifically, we review recent advances in the development and application of capillary electrophoresis‐mass spectrometry (CE‐MS) and on‐line analyte concentration techniques, and introduce the emerging field of microfluidics as a front end to mass spectrometry (MS).