Abstract In this study, spindle-like α-Fe2O3 mesocrystals/reduced-graphene-oxide composites modified glassy carbon electrode (α-Fe2O3/rGO/GCE) is developed for ultrasensitive electrochemical detection of DA. Morphologies and crystal structures of this composite are characterized by SEM, TEM, XRD, Raman spectrum, and XPS, respectively. The electrochemical behavior of DA on these electrodes are investigated by CV and EIS. The electrochemical conditions are optimized systematically. As results, the oxidation current of DA on α-Fe2O3/rGO/GCE is 38.13-fold increase than that on bare GCE. It is ascribed to the high catalytic activity of α-Fe2O3 mesocrystals and large electrochemical active area of rGO. Under the best voltammetric condition, wide linear detection range (from 1.0×10−8 to 9.0×10-4 mol/L) and low LOD of 3.26 nM (S/N=3) are obtained on the α-Fe2O3/rGO/GCE. Furthermore, this electrode is also used for DA detection in real human serums samples successfully. This α-Fe2O3/rGO/GCE provides a good example in design of other mesocrystals-based composite materials for electrochemical detection.

中文翻译：

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在纺锤体状 α-Fe2O3 介晶/rGO 修饰 GCE 上通过电化学途径超灵敏检测多巴胺

摘要 在本研究中，开发了纺锤状 α-Fe2O3 介晶/还原氧化石墨烯复合材料修饰的玻碳电极 (α-Fe2O3/rGO/GCE) 用于 DA 的超灵敏电化学检测。该复合材料的形貌和晶体结构分别通过 SEM、TEM、XRD、拉曼光谱和 XPS 进行表征。DA 在这些电极上的电化学行为通过 CV 和 EIS 进行研究。电化学条件被系统地优化。结果表明，DA 在 α-Fe2O3/rGO/GCE 上的氧化电流是裸 GCE 上的 38.13 倍。这归因于 α-Fe2O3 介晶的高催化活性和 rGO 的大电化学活性面积。在最佳伏安条件下，线性检测范围宽（从 1.0×10−8 到 9.0×10-4 mol/L）和 3 的低 LOD。在 α-Fe2O3/rGO/GCE 上获得 26 nM (S/N=3)。此外，该电极还成功用于真实人血清样品中的 DA 检测。这种 α-Fe2O3/rGO/GCE 为设计用于电化学检测的其他介晶复合材料提供了一个很好的例子。