Reductive Mode Thin-Layer Amperometric Detector for Liquid Chromatography

Abstract

An electrochemical detector for liquid chromatography is described based on the use of a mercury film electrode in a thin-layer cell with the auxiliary electrode placed across the channel from the working electrode. Considerations relevant to optimizing performance of the detector are described including removal of dissolved oxygen from the sample and mobile phase. Detection limits are reported for a number of reducible organic compounds of interest in environmental and biomedical research. Detection limits at the picomole level are readily achieved for easily reduced nitro compounds. Typical applications are illustrated for the determination of parathion in field runoff water and chloramphenicol in human plasma.