Development of an amperometric L-ascorbic acid (Vitamin C) sensor based onelectropolymerised aniline for pharmaceutical and food analysis

A sensor has been developed that selectively catalyses the oxidation of L-a scorbic acid at low potentials (+100 mV). The low applied potential minimis es the effects of many common electrochemical interferents. The interferent s tested are those commonly found in juices and pharmaceutical preparations , including 4-acetamidophenol (paracetamol), uric acid and citric acid. Pol yaniline was grown on both glassy carbon and screen-printed electrodes, and the analytical behaviour of both sensor types investigated. The linear ran ges of the batch mode sensors were determined to be between 0.4 muM and 2 m M, with a limit of detection of 0.4 muM, while in flow injection format the linear range extended from 5 muM to 0.1 mM with a Limit of detection of 2. 45 muM. (C) 2001 Elsevier Science B.V. All rights reserved.