Du Yun, Shen Yuru, Zeng Xingyu, Chen Mingjian, Zeng Xike, Huang Xiaobei, Xie Qingji
Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research (Ministry of Education of China), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, China; Changsha Center for Diseases Prevention and Control, Changsha 410004, China.
School of Material and Chemical Engineering, Tongren University, Tongren 554300, China.
Food Chem. 2025 Oct 15;489:144943. doi: 10.1016/j.foodchem.2025.144943. Epub 2025 May 27.
Quantitative analysis of organophosphorus-pesticide (e.g., methyl parathion (MP)) residues is important for environmental protection and food safety. Herein, a new method for MP analysis by rapid scan rate cyclic voltammetry (CV) is reported. The sensing electrode is a gold nanoparticles (AuNPs)/polypyrrole (PPy)/carboxylated multiwalled carbon nanotubes (HOOC-MWCNTs)/glassy carbon electrode (GCE) after various instrumental characterizations, which was fabricated by sequentially modifying a GCE with HOOC-MWCNTs (cast-coating), PPy (electropolymerization), and AuNPs (electrodeposition). Potential cycling of the AuNPs/PPy/HOOC-MWCNTs/GCE in 0.1 M phosphate buffer solution (pH 6.5) containing MP shows a pair of rather reversible and evident redox peaks of electroreduced MP, which enables the rapid scan rate CV analysis of MP and shows a linearity from 0.10 to 20.0 μM with a limit of detection of 5.0 nM (S/N = 3). The quantitative analysis of MP in vegetable extracts and environmental water samples gives satisfactory results.
有机磷农药（如甲基对硫磷（MP））残留量的定量分析对于环境保护和食品安全至关重要。在此，报道了一种通过快速扫描速率循环伏安法（CV）分析MP的新方法。经过各种仪器表征后，传感电极是金纳米颗粒（AuNPs）/聚吡咯（PPy）/羧基化多壁碳纳米管（HOOC-MWCNTs）/玻碳电极（GCE），它是通过依次用HOOC-MWCNTs（流延涂层）、PPy（电聚合）和AuNPs（电沉积）修饰GCE制备而成。在含有MP的0.1 M磷酸盐缓冲溶液（pH 6.5）中，AuNPs/PPy/HOOC-MWCNTs/GCE的电位循环显示出一对相当可逆且明显的电还原MP的氧化还原峰，这使得能够对MP进行快速扫描速率CV分析，并且在0.10至20.0 μM范围内呈线性，检测限为5.0 nM（S/N = 3）。对蔬菜提取物和环境水样中MP的定量分析给出了令人满意的结果。
