Zhang Hanwen, Jin Jiabin, Wang Xini, Han Wei, Qin Lei, Chen Lin, Mao Xiaoyan, Liu Zhenjiang, Xiang Xingwei
College of Food Science and Technology, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China.
National Narcotic Laboratory Zhejiang Regional Center (NNLZRC), Hangzhou, Zhejiang 310021, China.
Sci Total Environ. 2024 May 10;924:171512. doi: 10.1016/j.scitotenv.2024.171512. Epub 2024 Mar 5.
The presence of pesticide residues in aquatic environments poses a significant threat to both aquatic ecosystems and human health. The presence of these residues can result in significant harm to aquatic ecosystems and can negatively impact the health of aquatic organisms. Consequently, this issue requires urgent attention and effective measures to mitigate its impact. However, developing sensitive and rapid detection methods remains a challenge. In this study, an all-in-one test strip, which integrated bioenzymes, nanoenzymes, and a chromogen, was developed in combination with an enzyme labeling instrument for a highly sensitive and convenient sensing of malathion residues. The oxidase activity of heme chloride (Hemin) in the strip can catalyze the oxidation of HO and 3,3',5,5'-tetramethylbenzidine (TMB) to produce a blue-colored oxide. Simultaneously, the alkaline phosphatase (ALP) present in the strip can break down l-ascorbic acid-2-phosphate to produce ascorbic acid (AA). This AA then acts to reduce the oxidized form of TMB, turning it into a colorless substance and leading to the disappearance of its fluorescent signal. In the presence of a pesticide, the activity of ALP is inhibited and formation of AA is blocked, thereby preventing the reduction of oxidized TMB and producing a colored signal. According to this principle, the integrated test strip detected the target pesticide with high performance as per the optical density value determined via an enzyme marker. The detection limit of the test strip was 0.209 ng/mL with good sensitivity. The method was used for detecting malathion in actual river water samples, and the recoveries were in the range of 93.53 %-96.87 %. The newly devised technique effectively identified malathion in samples of natural water. This research has introduced a novel approach for the precise and convenient surveillance of pesticide remnants. Additionally, these discoveries could inspire the advancement of proficient multi-enzyme detection systems.
水生环境中农药残留的存在对水生生态系统和人类健康都构成了重大威胁。这些残留的存在会对水生生态系统造成严重损害，并可能对水生生物的健康产生负面影响。因此，这个问题需要紧急关注并采取有效措施来减轻其影响。然而，开发灵敏且快速的检测方法仍然是一项挑战。在本研究中，结合酶标仪开发了一种集成生物酶、纳米酶和显色剂的一体化检测试纸条，用于高灵敏且便捷地检测马拉硫磷残留。试纸条中氯化血红素（Hemin）的氧化酶活性可催化HO和3,3',5,5'-四甲基联苯胺（TMB）氧化生成蓝色氧化物。同时，试纸条中存在的碱性磷酸酶（ALP）可分解L-抗坏血酸-2-磷酸生成抗坏血酸（AA）。然后，这种AA会将氧化形式的TMB还原，使其变成无色物质并导致其荧光信号消失。在有农药存在的情况下，ALP的活性受到抑制，AA的形成被阻断，从而阻止氧化TMB的还原并产生显色信号。根据这一原理，集成检测试纸条根据酶标仪测定的光密度值对目标农药进行了高性能检测。试纸条的检测限为0.209 ng/mL，灵敏度良好。该方法用于检测实际河水样品中的马拉硫磷，回收率在93.53% - 96.87%范围内。新设计的技术有效地鉴定了天然水样中的马拉硫磷。这项研究引入了一种精确且便捷监测农药残留的新方法。此外，这些发现可能会激发高效多酶检测系统的发展。
