Coupling electrochemistry to capillary electrophoresis-mass spectrometry

• Electrochemistry (EC) with capillary electrophoresis-mass spectrometry (CE-MS).
• On-line coupling of EC with CE-MS is possible.
• EC is a means to enable CE-MS studies of neutral compounds.
• Electrochemical flow cell with screen-printed electrodes can be coupled directly to MS.

Hyphenated techniques have become an important tool in modern analytical research. Among detection techniques, mass spectrometry (MS) plays a dominant role, but efficient analyte separation prior to MS detection is usually desirable, as it provides the basis for reliable qualitative and quantitative determination. However, electrochemical methods offer very versatile approaches for selective sample pretreatment or analyte conversion. This review summarizes recent instrumental analytical developments, which resulted in a special kind of a hyphenated system: electrochemistry-capillary electrophoresis-MS (EC-CE-MS). We discuss the analytical characteristics of this approach and compare them with those of other techniques coupling EC with separation techniques and MS.