Kang Jia, Qi Meng, Wang Yasen, Li Linchun, Zhou Xinda, An Xiaoshuo, Hammock Bruce D, Zhang Jinlin, Huo Jingqian
Hebei Agricultural University.
Langfang Normal University.
Res Sq. 2025 Jul 15:rs.3.rs-7065158. doi: 10.21203/rs.3.rs-7065158/v1.
Atrazine, one of the mostly used herbicides globally, is characterized as long residual effects on sensitive crops such as wheat, soybeans, and sweet potatoes. Also, its prolonged residues in the environment can jeopardize the health of non-target organisms and the safety of environmental ecosystems. Therefore, it is important to develop efficient and sensitive methods to detect trace atrazine in the environment. In this study, the nanobodies specifically recognizing atrazine were successfully obtained through immunize alpaca and phage display libraries, and an indirect competitive immunoassay (ic-ELISA) based on nanobodies was constructed with an of 0.062 μg/mL and a minimum detection limit of 0.01 μg/mL. Meanwhile, an Au@PtNPs with excellent colorimetric performance, high catalytic activity, and high stability was synthesized. The combination of Au@PtNPs and nanobodies led to the development of a direct competitive immunoassay (dc-ELISA) with higher specificity, convenience, lower cost and an value of 0.032 μg/mL which was lower than the ic-ELISA. Based on the Au@PtNPs and nanobodies, a novel LFIA model for qualitative and semi-quantitative detection of atrazine was constructed with a minimum detection limit of 5 ng/mL. The present study is of great significance for the construction of atrazine immunoassay combining nanobodies and nanoenzymes, which provides a sensitive, specific, simple and reliable method for the detection of atrazine in the environment.
阿特拉津是全球使用最广泛的除草剂之一，其特点是对小麦、大豆和红薯等敏感作物具有长期残留效应。此外，它在环境中的长期残留会危害非靶标生物的健康和环境生态系统的安全。因此，开发高效、灵敏的方法来检测环境中的痕量阿特拉津具有重要意义。在本研究中，通过免疫羊驼和噬菌体展示文库成功获得了特异性识别阿特拉津的纳米抗体，并构建了基于纳米抗体的间接竞争免疫分析（ic-ELISA），其半数抑制浓度为0.062μg/mL，最低检测限为0.01μg/mL。同时，合成了具有优异比色性能、高催化活性和高稳定性的Au@PtNPs。Au@PtNPs与纳米抗体的结合导致开发出一种直接竞争免疫分析（dc-ELISA），具有更高的特异性、便利性、更低的成本，且半数抑制浓度值为0.032μg/mL，低于ic-ELISA。基于Au@PtNPs和纳米抗体，构建了一种用于定性和半定量检测阿特拉津的新型侧向流动免疫分析（LFIA）模型，最低检测限为5 ng/mL。本研究对于构建结合纳米抗体和纳米酶的阿特拉津免疫分析具有重要意义，为环境中阿特拉津的检测提供了一种灵敏、特异、简单且可靠的方法。
