A new electrochemical sensor based on Fe₃O₄@SiO₂‐PANI‐Au nanocomposite was fabricated for modification of glassy carbon electrode (Fe₃O₄@SiO₂‐PANI‐Au GCE). The Fe₃O₄@SiO₂‐PANI‐Au nanocomposite was characterized by TEM, FESEM‐EDS‐Mapping, XRD, and TGA methods. The Fe₃O₄@SiO₂‐PANI‐Au GC electrode exhibited an acceptable sensitivity, fast electrochemical response, and good selectivity for determination of quercetin. Under optimal conditions, the linear range for quercetin concentrations using this sensor was 1.0×10⁻⁸ to 1.5×10⁻⁵ mol L⁻¹, and the limit of detection was 3.8×10⁻⁹ mol L⁻¹. The results illustrated that the offered sensor could be a possible alternative for the measurement of quercetin in food samples and biological fluids.

中文翻译：

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Fe3O4 @ SiO2-PANI-Au纳米复合材料，用于电化学测定食品样品和生物液体中的槲皮素

制备了一种基于Fe ₃ O ₄ @SiO ₂ -PANI-Au纳米复合材料的电化学传感器，用于修饰玻碳电极（Fe ₃ O ₄ @SiO ₂ -PANI-Au GCE）。通过TEM，FESEM-EDS-Mapping，XRD和TGA方法对Fe ₃ O ₄ @SiO ₂ -PANI-Au纳米复合材料进行了表征。Fe ₃ O ₄ @SiO ₂ -PANI-Au GC电极表现出可接受的灵敏度，快速的电化学响应以及对槲皮素测定的良好选择性。在最佳条件下，使用该传感器的槲皮素浓度的线性范围为1.0×10 ^-8至1.5×10 ^-5  mol L ^-1，检测限为3.8×10 ^-9  mol L ^-1。结果表明，所提供的传感器可以替代食品样品和生物液体中槲皮素的含量。