AbstractAn amperometric sensor for L-Cys is described which consists of a glassy carbon electrode (GCE) that was modified with reduced graphene oxide placed in a Nafion film and decorated with palladium nanoparticles (PdNPs). The film was synthesized by a hydrothermal method. The PdNPs have an average diameter of about 10 nm and a spherical shape. The modified GCE gives a linear electro-oxidative response to L-Cys (typically at +0.6 V vs. SCE) within the 0.5 to 10 μM concentration range. Other figures of merit include a response time of less than 2 s, a 0.15 μM lower detection limit (at signal to noise ratio of 3), and an analytical sensitivity of 1.30 μA·μM−1·cm−2. The sensor displays selectivity over ascorbic acid, uric acid, dopamine, hydrogen peroxide, urea, and glucose. The modified GCE was applied to the determination of L-Cys in human urine samples and gave excellent recoveries. Graphical abstractSpherical palladium nanoparticles (PdNPs) on reduced graphene oxide-Nafion (rGO-Nf) films were synthesized using a hydrothermal method. This nanohybrid was used for modifying a glassy carbon electrode to develop a sensor electrode for detecting L-cysteine that has fast response (less than 2 s), low detection limit (0.15 μM), and good sensitivity (0.092 μA μM-1 cm-2).

中文翻译：

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使用在 Nafion 基质中的还原氧化石墨烯上生长的钯纳米粒子修饰的玻碳电极对 L-半胱氨酸进行电流法测定

摘要描述了一种用于 L-Cys 的电流传感器，它由玻璃碳电极 (GCE) 组成，该电极被放置在 Nafion 膜中的还原氧化石墨烯修饰并用钯纳米粒子 (PdNPs) 装饰。该薄膜是通过水热法合成的。PdNPs 的平均直径约为 10 nm，呈球形。在 0.5 到 10 μM 的浓度范围内，改进的 GCE 对 L-Cys（通常为 +0.6 V 与 SCE）产生线性电氧化响应。其他优点包括响应时间小于 2 秒、检测下限为 0.15 μM（信噪比为 3）和分析灵敏度为 1.30 μA·μM-1·cm-2。该传感器对抗坏血酸、尿酸、多巴胺、过氧化氢、尿素和葡萄糖具有选择性。改进的 GCE 用于测定人尿样品中的 L-Cys，并获得了极好的回收率。图形摘要使用水热法合成了还原氧化石墨烯-Nafion (rGO-Nf) 薄膜上的球形钯纳米粒子 (PdNP)。该纳米杂化物用于修饰玻碳电极，开发出响应快（小于2 s）、低检测限（0.15 μM）和良好灵敏度（0.092 μA μM-1 cm-）的L-半胱氨酸检测传感器电极。 2）。