Abstract This work presents the development of a sensor based on reduced graphene oxide (rGO) modified with silver nanoparticles (AgNPs) for the oxidation of estriol hormone. The morphology and electrochemical behavior of the rGO-AgNPs composite was characterized by scanning electron microscopy and cyclic voltammetry, demonstrating that the AgNPs were incorporated into rGO. The transfer of an electron from the estriol molecule for the working electrode at + 0.45 V, and the consequent loss of an H + ion for the buffer solution was confirmed combining electrochemical experiments and molecular modelling techniques. The glassy carbon (GC) electrode modified with the rGO/AgNPs composite was optimized for the determination of estriol using differential pulse voltammetry (DPV), achieving detection limit of 21.0 nmol L − 1 for estriol hormone. Reproducibility and repeatability values of 1.5% and 1.3%, respectively, were obtained compared to the conventional procedure. The proposed GC/rGO-AgNPs electrochemical device was successfully applied to the determination of estriol in tap water and synthetic urine samples.

中文翻译：

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用银纳米粒子修饰的还原氧化石墨烯用于雌三醇的电化学检测

摘要 这项工作提出了一种基于还原氧化石墨烯 (rGO) 的传感器的开发，该传感器用银纳米粒子 (AgNP) 修饰，用于氧化雌三醇激素。通过扫描电子显微镜和循环伏安法表征了 rGO-AgNPs 复合材料的形态和电化学行为，表明 AgNPs 被结合到 rGO 中。结合电化学实验和分子建模技术，证实了在 + 0.45 V 时工作电极的雌三醇分子的电子转移以及缓冲溶液中 H + 离子的损失。使用微分脉冲伏安法 (DPV) 对用 rGO/AgNPs 复合材料修饰的玻璃碳 (GC) 电极进行优化，以测定雌三醇，雌三醇激素的检测限为 21.0 nmol L - 1。与传统程序相比，重现性和重复性值分别为 1.5% 和 1.3%。所提出的 GC/rGO-AgNPs 电化学装置已成功应用于测定自来水和合成尿液样品中的雌三醇。