Bao Jing, Hou Changjun, Chen Mei, Li Junjie, Huo Danqun, Yang Mei, Luo Xiaogang, Lei Yu
Key Laboratory of Biorheological Science and Technology (Chongqing University), Ministry of Education, Bioengineering College, Chongqing University , Chongqing 400030, China.
Department of Chemical and Biomolecular Engineering, University of Connecticut , 191 Auditorium Road, Unit 3222, Storrs, Connecticut 06269, United States.
J Agric Food Chem. 2015 Dec 2;63(47):10319-26. doi: 10.1021/acs.jafc.5b03971. Epub 2015 Nov 18.
As broad-spectrum pesticides, organophosphates (OPs) are widely used in agriculture all over the world. However, due to their neurotoxicity in humans and their increasing occurrence in the environment, there is growing interest in their sensitive and selective detection. This paper reports a new cost-effective plant esterase-chitosan/gold nanoparticles-graphene nanosheet (PLaE-CS/AuNPs-GNs) biosensor for the sensitive detection of methyl parathion and malathion. Highly pure plant esterase is produced from plants at low cost and shares the same inhibition mechanism with OPs as acetylcholinesterase, and then it was used to prepare PLaE-CS/AuNPs-GNs nanocomposites, which were systematically characterized using SEM, TEM, and UV-vis. The PLaE-CS/AuNPs-GNs composite-based biosensor measured as low as 50 ppt (0.19 nM) of methyl parathion and 0.5 ppb (1.51 nM) of malathion (S/N = 3) with a calibration curve up to 200 ppb (760 nM) and 500 ppb (1513.5 nM) for methyl parathion and malathion, respectively. There is also no interference observed from most of common species such as metal ions, inorganic ions, glucose, and citric acid. In addition, its applicability to OPs-contaminated real samples (carrot and apple) was also demonstrated with excellent response recovery. The developed simple, sensitive, and reliable PLaE-CS/AuNPs-GNs composite-based biosensor holds great potential in OPs detection for food and environmental safety.
作为广谱农药，有机磷酸酯（OPs）在世界各地的农业中被广泛使用。然而，由于其对人类的神经毒性以及在环境中日益频繁的出现，人们对其灵敏且选择性的检测越来越感兴趣。本文报道了一种新型的具有成本效益的植物酯酶-壳聚糖/金纳米粒子-石墨烯纳米片（PLaE-CS/AuNPs-GNs）生物传感器，用于灵敏检测甲基对硫磷和马拉硫磷。高纯度的植物酯酶可低成本地从植物中制备，并且与有机磷酸酯具有与乙酰胆碱酯酶相同的抑制机制，然后用其制备PLaE-CS/AuNPs-GNs纳米复合材料，通过扫描电子显微镜（SEM）、透射电子显微镜（TEM）和紫外可见光谱对其进行了系统表征。基于PLaE-CS/AuNPs-GNs复合材料的生物传感器对甲基对硫磷的检测下限低至50 ppt（0.19 nM），对马拉硫磷的检测下限低至0.5 ppb（1.51 nM）（信噪比S/N = 3），甲基对硫磷和马拉硫磷的校准曲线分别高达200 ppb（760 nM）和500 ppb（1513.5 nM）。大多数常见物质如金属离子、无机离子、葡萄糖和柠檬酸均未观察到干扰。此外，还证明了其对受有机磷酸酯污染的实际样品（胡萝卜和苹果）具有良好的响应回收率。所开发的基于PLaE-CS/AuNPs-GNs复合材料的简单、灵敏且可靠的生物传感器在用于食品和环境安全的有机磷酸酯检测中具有巨大潜力。
