A fresh strategy based on two-step electrochemical reduction for the fabrication of palladium nanoparticles/reduced oxide nanocomposite-modified glass carbon electrode (PdNPs/rGO/GCE) was established in this study. Field emission scanning electron microscopy (FESEM) images showed that spherical PdNPs were evenly distributed on the surface of rGO-modified electrode (rGO/GCE), and the introduction of PdNPs has no effect on the morphology of rGO. Electrochemical impedance spectroscopy (EIS) studies revealed that the conductivity of PdNPs/rGO/GCE was higher than that of rGO/GCE and bare GCE. The electrochemical performances of PdNPs/rGO/GCE sensor were investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and chronoamperometry using ascorbic acid (AA), dopamine (DA), and uric acid (UA) as analytes. At the optimized conditions, wide linear ranges of 0.5–3.5 mM (R² = 0.99), 3–15 μM (R² = 0.99) and 15–42 μM (R² = 0.99), and 0.3–1.4 mM (R² = 0.99) towards AA, DA, and UA in ternary mixture were observed, respectively. In addition to superior anti-interference capability, fast response (≤5 s), excellent reproducibility, and good long-term stability were also given by this sensor. These results suggested that PdNPs/rGO/GCE is promising for the simultaneous detection of AA, DA, and UA in practical application.

中文翻译：

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基于钯纳米颗粒/还原氧化石墨烯纳米复合材料的新型电化学传感器同时检测抗坏血酸，多巴胺和尿酸

本研究建立了一种新的基于两步电化学还原的策略，用于制备钯纳米颗粒/还原氧化物纳米复合材料修饰的玻璃碳电极（PdNPs / rGO / GCE）。场发射扫描电子显微镜（FESEM）图像显示球形PdNPs均匀地分布在rGO修饰电极（rGO / GCE）的表面上，并且PdNPs的引入对rGO的形态没有影响。电化学阻抗谱（EIS）研究表明，PdNPs / rGO / GCE的电导率高于rGO / GCE和裸露的GCE。使用抗坏血酸（AA），多巴胺（DA）和尿酸（UA）作为分析物，通过循环伏安法（CV），微分脉冲伏安法（DPV）和计时电流法研究了PdNPs / rGO / GCE传感器的电化学性能。在最佳条件下[R ²  = 0.99），3-15  μ M（- [R ²  = 0.99）和15-42  μ M（- [R ²  = 0.99），和0.3mm〜毫米（- [R ²  = 0.99）朝向AA，DA，和UA在三元分别观察到混合物。除了出色的抗干扰能力外，该传感器还具有快速响应（≤5s），出色的重现性和良好的长期稳定性。这些结果表明，PdNPs / rGO / GCE在实际应用中有望同时检测AA，DA和UA。