Development of an amperometric sensor for phenol compounds using a Nafion (R) membrane doped with copper dipyridyl complex as a biomimetic catalyst

The use of [CuDipyCl(2)] as a biomimetic catalyst in the construction of an amperometric enzymeless biosensor for phenol determinations is reported. The sensor was prepared modifying a glassy carbon electrode with a Nafio((R)) membrane doped with [CuDipyCl(2)]. The sensor presented a higher response for dopamine in 0.1 mol l(-1) phosphate buffer at pH 7, with an applied potential of -50 mV versus SCE. With the optimized operational conditions a linear response range between 4.0 x 10(-5) and 6.0 x 10(-4) Mol l(-1), with a sensitivity of 350 +/- 10 nA 1 mmol(-1) cm(-2) and a detection limit of 9.0 x 10(-6) Mol l(-1) were observed for the sensor. The response time presented for this sensor was approximately 1 s, presenting the same response for at least 50 measurements, with good repeatability (R.S.D. 3.8%, for n = 9). The difference of the response between four preparations was 7%. Detailed investigations of the sensor response for monophenol and diphenol compounds and interfering species were carried out. (C) 2002 Elsevier Science B.V. All rights reserved.53641671718