Hunan Key Laboratory of Biomedical Nanomaterials and Devices, College of Life Sciences and Chemistry, Hunan University of Technology, Zhuzhou, 412007, China.
Hunan Key Laboratory of Biomedical Nanomaterials and Devices, College of Life Sciences and Chemistry, Hunan University of Technology, Zhuzhou, 412007, China; Department of Chemistry and Material Science, Hengyang Normal University, Hengyang 421008, China.
Colloids Surf B Biointerfaces. 2018 Dec 1;172:565-572. doi: 10.1016/j.colsurfb.2018.09.005. Epub 2018 Sep 9.
A novel manganese dioxide nanorods-electrochemically graphene oxide nanocomposites modified glassy carbon electrode (MnONRs-ErGO/GCE) was developed for the rapid and sensitive detection of Amaranth in foodstuffs. The morphology, structure and composition of MnONRs, ErGO, and MnO/ErGO were characterized by SEM and XRD. The electrochemical behavior of Amaranth on the bare GCE, ErGO/GCE, and MnONRs-ErGO/GCE were investigated by cyclic voltammetry and electrochemical impedance spectroscopy. The voltammetric conditions (including pH, scan rate, accumulation potential as well as time) were optimized systematically. Due to large electrochemical active area and low charge transfer resistance, the MnONRs-ErGO/GCE exhibited a great enhancement effect on the oxidation of Amaranth, and significant increased the oxidation peak current i (approximately 38-fold increase compared to that of bare GCE). Under the optimum voltammetric conditions, the i varied linearly with Amaranth concentration in the range of 0.02 μM-10 μM, and 10 μM-400 μM with a low detection limit of 1.0 nM (S/N = 3). Moreover, satisfactory results were obtained in the analysis of real samples. Together with the merits of rapidness, cost-effectivity, high sensitivity and selectivity, the result suggests the proposed MnONRs-ErGO/GCE have broad application prospects on the sensitive detection of Amaranth in various real samples.
一种新型的二氧化锰纳米棒-电化学氧化石墨烯纳米复合材料修饰玻碳电极（MnONRs-ErGO/GCE）被开发用于快速灵敏地检测食品中的苋菜红。通过 SEM 和 XRD 对 MnONRs、ErGO 和 MnO/ErGO 的形貌、结构和组成进行了表征。通过循环伏安法和电化学阻抗谱研究了苋菜红在裸 GCE、ErGO/GCE 和 MnONRs-ErGO/GCE 上的电化学行为。系统优化了伏安条件（包括 pH、扫描速率、累积电位和时间）。由于具有较大的电化学活性面积和较低的电荷转移电阻，MnONRs-ErGO/GCE 对苋菜红的氧化表现出了很好的增强效果，显著增加了氧化峰电流 i（与裸 GCE 相比约增加了 38 倍）。在最佳伏安条件下，i 在 0.02 μM-10 μM 和 10 μM-400 μM 范围内与苋菜红浓度呈线性关系，检测限低至 1.0 nM（S/N=3）。此外，在实际样品分析中得到了令人满意的结果。该方法具有快速、经济、高灵敏度和选择性的优点，表明所提出的 MnONRs-ErGO/GCE 在各种实际样品中对苋菜红的灵敏检测具有广阔的应用前景。
