In the present work, an effective electrochemical sensor for the rapid and selective determination of epinephrine (EP) in the presence of uric acid (UA) based on a glassy carbon electrode (GCE) modified with gold nanoparticles (AuNPs) and cysteic acid was applied. This modified electrode exhibited a potent and persistent electron mediating behavior followed by well separated oxidation peaks of EP and UA. The surface and electrochemical characterization of the modified electrode was performed by field emission scanning electron microscopy (FESEM), chronocoulometry (CC), cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The effective surface area (0.087 cm²) which is 4.8 times as much as that of the unmodified GCE, electron transfer coefficient (α = 0.31) and number of electrons involved in the rate determining step (n_α = 2.2 ≈ 2) for EP were also determined using electrochemical approaches. Under optimal conditions, the AuNPs/cysteic acid/GCE displays a linear response for 0.4–11.7 μM EP and a good detection sensitivity of 1.2631 μA μM⁻¹ and the detection limit is 80 nM (S/N = 3). The suggested sensor was successfully used for the determination of analytes in real samples with satisfactory results.

中文翻译：

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尿酸存在下肾上腺素的选择性分析，方法是使用放大的电化学传感器，该传感器采用金纳米颗粒修饰的半胱氨酸膜

在当前的工作中，应用了一种有效的电化学传感器，该传感器基于金纳米颗粒（AuNPs）和半胱氨酸修饰的玻碳电极（GCE）在尿酸（UA）存在下快速和选择性地测定肾上腺素（EP）。 。这种修饰的电极表现出强而持久的电子介导行为，其后是EP和UA的良好分离的氧化峰。通过场发射扫描电子显微镜（FESEM），计时库仑法（CC），循环伏安法（CV）和微分脉冲伏安法（DPV）对修饰电极的表面和电化学特性进行了表征。有效表面积（0.087 cm ²）是未修饰的GCE的4.8倍，电子传递系数（α= 0.31），并参与了速率确定步骤的电子的数量（Ñ _α = 2.2≈2）EP还使用电化学方法来确定的。在最佳条件下，AuNPs /半胱氨酸/ GCE对0.4-11.7μMEP表现出线性响应，并具有1.2631μAμM ^-1的良好检测灵敏度，检测限为80 nM（S / N = 3）。所建议的传感器已成功用于实际样品中分析物的测定，结果令人满意。