Application of a voltammetric flow-through cell to flow-injection-analysis (FIA)

Abstract

A new voltammetric flow-through cell has been designed to be used as an electrochemical detector in HPLC (high performance liquid chromatography) and may also be used as a voltammetric detector of FIA (flow-injection-analysis). The cell is of wall jet type and has a volume of approximately 1μl. Performance of the cell was tested and the flow-characteristic determined by analysing paracetamol which is oxidized at a glassy carbon electrode and is frequently used as a pain-killing drug. Application of d.c. (direct current) and n.p. (normal pulse) voltammetric working modes in FIA were studied. D.c. was found to be more sensitive and should be used when low sample concentrations are determined. N.p. was, however, found to give more reproducible results at high concentrations. A known tablet formulation containing paracetamol was analyzed by the proposed method and a good agreement was found between the result obtained and the manufacturer's certificate.