Postchromatographic electrochemical detection of carbohydrates at a silver oxide electrode

Silver electrodes, when conditioned at sufficiently positive potentials in the presence of a strong base, can be made to form a silver(I) oxide or silver(II) oxide surface. In the presence of this oxide surface, carbohydrates may be oxidized and quantitated by means of an electrocatalytic scheme. The current which flows to reoxidize the charge‐transfer mediator (silver oxide) is directly related to concentration of carbohydrate. Rectilinear response is obtained over at least two decades of concentration (104 M to 10−6 M). Design of a prototype electrochemical cell and studies of optimum cell conditions are discussed. The application of a high‐performance liquid chromatography (HPLC) detector for the separation of some common sugars is illustrated.