Departamento de Química de los Materiales, Facultad de Química y Biología, Universidad de Santiago de Chile (USACH), Santiago 3363, Chile.
Departamento de Química de los Materiales, Facultad de Química y Biología, Universidad de Santiago de Chile (USACH), Santiago 3363, Chile.
Food Chem. 2020 Aug 15;321:126682. doi: 10.1016/j.foodchem.2020.126682. Epub 2020 Mar 23.
An inexpensive and environmental friendly electrochemical sensor based on a glassy carbon electrode (GC) modified with graphene quantum dots (GQDs) and Nafion (NF) has been developed for the determination of Cd(II) and Pb(II) in bivalve mollusks using square wave anodic stripping voltammetry (SWASV). GQDs were characterized by UV-Vis spectroscopy, fluorescence and transmission electronic microscopy (TEM). The modified electrode was evaluated by cyclic voltammetry, scanning electronic microscopy (SEM) and electrochemical impedance spectroscopy (EIS). A linearity of 20-200 μg L was found, with a limit of detection (LOD) of 11.30 μg L for Cd(II) and 8.49 μg L for Pb(II). The proposed methodology was validated with a certified reference material TMDA-64.2. The reproducibility of GC/GQDs-NF for both species had an RSD of less than 10%. The results were compared with ICP-OES. The method was applied in the determination of Cd(II) and Pb(II) in bivalve mollusks samples with excellent results.
一种基于玻碳电极（GC）修饰的石墨烯量子点（GQDs）和 Nafion（NF）的廉价环保电化学传感器，已被开发用于使用方波阳极溶出伏安法（SWASV）测定双壳类软体动物中的 Cd(II)和 Pb(II)。GQDs 通过紫外-可见光谱、荧光和透射电子显微镜（TEM）进行了表征。修饰电极通过循环伏安法、扫描电子显微镜（SEM）和电化学阻抗谱（EIS）进行了评估。发现 Cd(II)的线性范围为 20-200μg L，检测限（LOD）为 11.30μg L，Pb(II)的线性范围为 8.49μg L。该方法已用认证参考物质 TMDA-64.2 进行了验证。对于两种物质，GC/GQDs-NF 的重现性的 RSD 均小于 10%。结果与 ICP-OES 进行了比较。该方法已应用于双壳类软体动物样品中 Cd(II)和 Pb(II)的测定，结果非常理想。
