A novel composite film derived from cysteic acid and PDDA-functionalized graphene: Enhanced sensing material for electrochemical determination of metronidazole

• Published in: Talanta (Oxford) Vol. 104; pp. 204 - 211
• Main Authors: Liu, Weilu, Zhang, Jianfu, Li, Cong, Tang, Liu, Zhang, Zhiquan, Yang, Ming
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 30-01-2013
• Subjects: Anti-Infective Agents - analysis; Anti-Infective Agents - chemistry; Cysteic acid; Cysteic Acid - chemistry; Electrochemical sensor; Electrochemical Techniques; Graphene; Graphite - chemistry; Humans; Lakes - chemistry; Metronidazole; Metronidazole - analysis; Metronidazole - chemistry; Polyethylenes - chemistry; Quaternary Ammonium Compounds - chemistry; Cysteic acid; Metronidazole; Electrochemical sensor; Graphene
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2012.11.013

A novel composite film derived from cysteic acid and poly(diallydimethylammonium chloride)-functionalized graphene (PDDA-GN) was employed as an enhanced electrode material for ultrasensitive determination of metronidazole. The cysteic acid/PDDA-GN composite film was prepared by the electrochemical grafting of cysteic acid onto the PDDA-GN coated glassy carbon electrode (GCE). The cyclic voltammetry investigations reveal that the peak current of metronidazole reduction at the cysteic acid/PDDA-GN/GCE was remarkably enhanced compared to the bare GCE, the cysteic acid/GCE and the PDDA-GN/GCE. This result implies the synergistic electrocatalytic effect of cysteic acid and PDDA-GN. The fabricated sensor shows linear response to metronidazole in the ranges of 10nM–1μM and 70μM–800μM, with a detection limit of 2.3nM (S/N=3). The heterogeneous electron transfer rate constant and the diffusion coefficient of metronidazole were further evaluated by rotating disk electrode experiments. Moreover, we applied the present method to the determination of metronidazole in urine and lake water with satisfactory results.
► Facile microwave-heating procedure for preparing PDDA-functionalized graphene. ► Cysteic acid/PDDA-functionalized graphene composite film as a new electrode material. ► High electrocatalytic activity for metronidazole reduction. ► Wide linear range, low detection limit for the determination of metronidazole. ► Application in practical samples with satisfactory results.