MEDIATED GLUCOSE BIOSENSOR BASED ON POLYVINYLFERROCENE

Polyvinylferrocene (PVF) was electrochemically deposited on platinum a nd carbon electrodes to form a stable and resilient film. During cycli c voltammetry in phosphate buffer, the PVF film deposited on carbon el ectrodes exhibited anodic and cathodic peaks at 214 and 68 mV, respect ively. Both types of electrodes, bearing electrodeposited PVF and cros slinked glucose oxidase, were responsive to glucose, but the carbon el ectrode appeared to provide a faster response and could determine gluc ose between 0.1 and 8 mM. When protected by a layer of polymer electro chemically formed from resorcinol and phenylenediamine, the mediated b iosensors based on PVF-deposited carbon electrodes were capable of det ermining glucose up to 25 mM with a response time of 1 min, for at lea st 50 repeated analyses with good reproducibility. The presence of amb ient oxygen, ascorbic acid (0.1 mM), and uric acid (0.5 mM) did not af fect their performance. When applied for the determination of the gluc ose level in reconstituted human serum, the results agreed well with t hose of the reference hexokinase assay.