The electrochemical characterization and determination of the antibiotic cefadroxil were carried out at multi‐walled carbon nanotube (CNT) and gold nanoparticle (AuNP) modified glassy carbon electrodes (GCE). Oxidation of the phenol moiety of cefadroxil occurred at slightly less‐positive potentials and with a higher current response than at bare GCE. Differential pulse voltammetry and electrochemical impedance spectroscopy showed that the architecture combining CNT and AuNP surface modification is the best in pH 7 buffer solution. Scanning electron microscopy demonstrated good coverage of the AuNPs on the CNTs. The fixed potential amperometric determination of cefadroxil was carried out at +0.74 V vs Ag/AgCl with a limit of detection of 0.22 μM. Analysis of cefadroxil in commercial samples presented high recovery values and the amount of the pharmaceutical in each capsule was in excellent agreement with that measured by UV/Vis spectroscopy.

中文翻译：

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碳纳米管/金纳米粒子修饰的玻碳电极上的头孢氨苄抗生素的电分析

在多壁碳纳米管（CNT）和金纳米颗粒（AuNP）修饰的玻碳电极（GCE）上进行了抗生素头孢氨苄的电化学表征和测定。与在裸露的GCE上相比，头孢羟氨苄的酚部分发生氧化时，正电势略低，电流响应更高。差示脉冲伏安法和电化学阻抗谱表明，结合了CNT和AuNP表面修饰的体系结构在pH 7缓冲溶液中是最好的。扫描电子显微镜显示了在CNT上的AuNP的良好覆盖。相对于Ag / AgCl，在+0.74 V的固定电位安培法测定头孢氨苄，检出限为0.22μM。