The use pulsed and amperometry combined with ion-exclusion chromatography for the simultaneous analysis of ascorbic acid and sulfite

Abstract

Initial attempts monitor ascorbic acid and sulfite, in a beer matrix, by combining ion-exclusion chromatography with a pulsed amperometric dectector using a single applied voltage to the platinum working electrode, were unsuccessful. Alternatively, good chromatograms for the separation of the two antioxidants were achieved utilizing a standard, amperometric cell. However, remarkably superior results were observed when this standard cell was operted in a pulsed mode and cleaning cycles were continually applied throughout the analysis. The working electrode stability and precision have been examined. Preliminary spike recovery data indicate acceptable accuracy for the method. Comparisons of this method to standard reference methods are currently ongoing.