Multichannel amperometric detection system for liquid chromatography and flow injection analysis

Abstract

more sophisticated technique like square-wave voltammetry (5-9) and coulostatic compensation of charging current (10-12) and/or by the use of microelectrodes (9,13,14). Another approach is the use of a potential scanning technique with a series configuration dual-electrode detector. The potential 0003-2700/91 /0363-2418S02.50/0 is scanned at the upstream electrode, and the current is monitored amperometrically at the downstream electrode (15, 16). However, in all mentioned cases, the detection limits are 2 or 3 orders of magnitude higher than those obtained by conventional amperometric detection systems.Another step toward three-dimensional information is the use of more working electrodes set at different potentials.

The use of silver solid amalgam electrode for voltammetric and amperometric determination of nitroquinolines

“…In our laboratory, an amperometric detector with MeSAE in "wall jet" geometry was developed [23] and tested on the determination of electrochemically active pesticides (2-methyl-4,6-dinitrophenol) and grow stimulators (4-nitrophenol) [23]. Further, gold amalgam electrodes and their modifications were used in flowing systems for detection of various biologically important substances, for example S-sulfocysteine [24] and cysteine [25], active plasma metabolite of a prodrug atriopeptidase inhibitor [26], glutathione [27], artemisinin and dihydroartemisinin (antimalaria drugs) [28] and epinephrine [29]. Copper amalgam electrode was used previously in flow arrangement for amperometric determination of metal-ions as Cu 2+ , Cd 2+ and Zn 2+ with limit of detection at 10 −11 mol L −1 level [30].…”

The Use of Silver Solid Amalgam Working Electrode for Determination of Nitrophenols by HPLC with Electrochemical Detection

“…Thanks to these qualities, the use of silver solid amalgam electrode (AgSAE) is possible in flow systems. Number of applications of amalgam electrodes such as HPLC-ED determination of catecholamines at gold amalgam electrode by multichannel amperometric detector [10], artemisinin, dihydroartemisinin, and artelinate at gold amalgam electrode [11] and FIA-ED determination of O(À II), Mn(II), Fe(II), I(À I), and HS(À I) in bioturbated sediments using gold amalgam microelectrode [12], cystine and S-sulfocystine using dual gold amalgam electrode [13] and 5-nitroquinoline and 6-nitroquinoline using meniscus modified AgSAE [14] have been described. The use of AgSAE for HPLC-ED has been only briefly mentioned [1,15].…”

Development and Possibilities of Multichannel Voltammetric Detection in Liquid Chromatography

“…However their application is not always successful. Another way to improve three-dimensional voltammetric detection would be the use of a multichannel working electrode set with several electrodes at different fixed potentials or with an offset in the potential scan [13][14][15][16][17][18][19][20].…”