USE OF ENZYMATIC REACTORS IN THE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC DETERMINATION OF ETHANOL AND METHANOL WITH ELECTROCHEMICAL DETECTION

Despite numerous applications both in industry and in analytical chemistry, immobilized enzyme technology has encountered only limited success in modern liquid chromatography. The strict requirements of enzymatic reactors for high performance liquid chromatography (HPLC) (i.e., mechanical resistance, limited void volumes, high contact surface, high binding capacity, stable enzyme‐to‐matrix bond without loss of enzyme activity) are not yet fully met by commercially available products. In our laboratory, the development of post‐column reactors with immobilized alcohol oxidase on‐line with an HPLC/EC system has been undertaken. Three home‐made reactors were produced: in the first alcohol oxidase from Candida boidinii was quasi‐immobilized onto an HPLC‐sized anion exchange support, in the second the enzyme was bound to a silica‐based support via Schiff's base formation, and in the third a covalent linkage to an epoxy‐activated hydroxyalkyl methacrylate material was chosen. Chemical immobilization proved superior to the ionic binding. The importance of limiting the post‐column band spreading due to the reactor void volume, by using HPLC‐sized supports, was confirmed. Copyright © 1990 John Wiley & Sons, Ltd.