AMPEROMETRIC DETECTOR FOR HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY, FEATURING A GLASSY-CARBON WORKING ELECTRODE ARRAY IN THE WALL-JET CONFIGURATION

A wall-jet segmented-ring-disc electrode array is applied:to reversed- phase HPLC. The segmented-ring electrode consists of eight independent glassy carbon discs, located around the central disc electrode. The e lectrode array is operated under amperometric conditions, and displays distinct qualitative. advantage over other modes of electrochemical d etection. The advantages are discussed in relation to data extraction from partially resolved chromatograms. The potential interference effe cts of closely eluting species are considered by the use af limited qu antitative data. The power to distinguish between co-eluting component s is clearly demonstrated by comparison with single-wavelength UV abso rbance detection. The analytes studied were phenol, 4-methylphenol, 2- nitrophenol, 4-nitrophenol, 2-chlorophenol and 4-chlorophenol. A furth er application of the electrode array is discussed, that of the analog ous operation to the wall-jet ring-disc electrode.