聚嘧啶/石墨烯复合材料修饰电极同时测定日落黄和酒石黄

采用液相剥离法制备石墨烯纳米片悬浮液,将其直接滴涂于玻碳电极表面,制备石墨烯修饰电极,再采用电沉积法制得聚嘧啶/石墨烯复合膜修饰电极。采用扫描电子显微镜对该修饰电极的表面形貌进行表征;采用循环伏安法和方波伏安法探究日落黄和酒石黄在该修饰电极上的电化学行为。结果表明,该复合膜修饰电极对两种合成色素均表现出良好的电催化性能。在优化实验条件下,日落黄和酒石黄同时被检测,线性检测范围分别为0.002~2?mol/L和0.003~6?mol/L,检测限分别为0.5 nmol/L和0.9 nmol/L。该方法可用于食品中日落黄和酒石黄的同时测定。

Polypyrimidine/Graphene Composite Film Modified Electrode for the Simultaneous Detection of Sunset Yellow and Tartrazine

Graphene nanosheets (GNs), which were prepared by liquid-phase exfoliation method, were directly casted ontothe surface of a glassy carbon electrode to obtain a graphene-modified electrode (GN/GCE). Then, the polypyrimidine/graphene composite film modified electrode (pAMP/GN/GCE) was fabricated by electrodeposition method. The surfacemorphology of the modified electrode was characterized by scanning electron microscope. Electrochemcial behaviors ofsunset yellow (SY) and tartrazine (TT) on pAMP/GN/GCE were investigated with cyclic voltammetry (CV) and squarewave voltammetry (SWV). The experimental results showed that the as-prepared electrode exhibited remarkable catalyticability for both SY and TT. Under the optimized experimental conditions, the linear ranges for detecting SY and TT were0.002–2 mmol/L and 0.003–6 mmol/L, respectively. The limits of detection (LODs) were as low as 0.5 and 0.9 nmol/L(RSN = 3), respectively. This developed method can be used for the simultaneous determination of SY and TT in food samples.