An amperometric polyphenol biosensor based on polyvinyl chloride membrane

A method is described for construction of a polyphenol biosensor employing polyvinylchloride membrane bound banana fruit polyphenol oxidase. The biosensor showed optimum response within 30 s, when operated at 0.4 V in 0.1 M sodium phosphate buffer, pH 7.5 and 35 °C. The detection limit of the method was 7.5 × 10−7 M. The analytical recovery of added L-DOPA was 93.50%. Within batch and between batch coefficients of variation were < 0.82% and < 1.65% respectively. The sensor was employed for amperometric determination of polyphenols in tea leaves, alcoholic beverages and water. The enzyme electrode was used 200 times over 60 days, when stored at 4 °C.