Mariyappan Vinitha, Keerthi Murugan, Chen Shen-Ming
Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, No.1, Section 3, Chung-Hsiao East Road, Taipei 106, Taiwan.
J Agric Food Chem. 2021 Mar 10;69(9):2679-2688. doi: 10.1021/acs.jafc.0c07522. Epub 2021 Mar 1.
Nowadays, a lot of pesticides have been used in the agriculture field due to the global demand for food production. Carbofuran (CF) is the most commonly used carbamate compound that is responsible for the highest toxicity to humans compared to any other pesticide used in agricultural settings. Thus, rapid, portable, and low-cost sensors are needed for the detection of CF in the environment and food samples. Herein, we have successfully developed an electrochemical sensor using a glassy carbon electrode (GCE) modified with gadolinium sulfide (GdS) and reduced graphene oxide (RGO) composite for the detection of carbofuran (CF). A novel GdS/RGO composite was prepared by the facile hydrothermal route and confirmed by morphological and structural analyses such as field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray (EDX), powder X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS), and also the formation mechanism of GdS/RGO composite was discussed. The desired electrical conductivity of GdS was enhanced by the RGO, which was estimated from the electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). Electrochemical studies demonstrated that the developed GdS/RGO sensor was highly sensitive and selective to CF. In addition, the GdS/RGO sensor exhibits a low detection limit (LOD) and the linear ranges were 0.0128 and 0.001-1381 μM, respectively, for CF detection under optimized experimental conditions. Moreover, we also investigated the practical applicability of the sensor for CF detection in the environment and food samples.
如今，由于全球对粮食生产的需求，农业领域使用了大量农药。克百威（CF）是最常用的氨基甲酸酯类化合物，与农业环境中使用的任何其他农药相比，它对人类的毒性最高。因此，需要快速、便携且低成本的传感器来检测环境和食品样品中的克百威。在此，我们成功开发了一种电化学传感器，该传感器使用硫化钆（GdS）和还原氧化石墨烯（RGO）复合材料修饰的玻碳电极（GCE）来检测克百威（CF）。通过简便的水热法制备了一种新型的GdS/RGO复合材料，并通过场发射扫描电子显微镜（FESEM）、高分辨率透射电子显微镜（HRTEM）、能量色散X射线（EDX）、粉末X射线衍射（XRD）、拉曼光谱和X射线光电子能谱（XPS）等形态和结构分析进行了确认，还讨论了GdS/RGO复合材料的形成机理。RGO提高了GdS所需的电导率，这是通过电化学阻抗谱（EIS）和循环伏安法（CV）估算得出的。电化学研究表明，所开发的GdS/RGO传感器对CF具有高灵敏度和选择性。此外，在优化实验条件下，GdS/RGO传感器对CF检测的检测限（LOD）较低，线性范围分别为0.0128和0.001 - 1381 μM。此外，我们还研究了该传感器在环境和食品样品中检测CF 的实际适用性。
