School of Chemistry and Chemical Engineering, Key Laboratory of Hubei Province for Coal Conversion and New Carbon Materials, Wuhan University of Science and Technology, Wuhan 430081, P. R. China.
National Key Laboratory of Green Pesticide, International Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry, Central China Normal University, Wuhan 430079, P. R. China.
Anal Chem. 2024 Apr 16;96(15):6072-6078. doi: 10.1021/acs.analchem.4c00789. Epub 2024 Apr 5.
The urgent need for sensitive and accurate assays to monitor acetylcholinesterase (AChE) activity and organophosphorus pesticides (OPs) arises from the imperative to safeguard human health and protect the ecosystem. Due to its cost-effectiveness, ease of operation, and rapid response, nanozyme-based colorimetry has been widely utilized in the determination of AChE activity and OPs. However, the rational design of nanozymes with high activity and specificity remains a great challenge. Herein, trace amount of Bi-doped core-shell Pd@Pt mesoporous nanospheres (Pd@PtBi) have been successfully synthesized, exhibiting good peroxidase-like activity and specificity. With the incorporation of trace bismuth, there is a more than 4-fold enhancement in the peroxidase-like performance of Pd@PtBi compared to that of Pd@Pt. Besides, no significant improvement of oxidase-like and catalase-like activities of Pd@PtBi was found, which prevents interference from O and undesirable consumption of substrate HO. Based on the blocking impact of thiocholine, a colorimetric detection platform utilizing Pd@PtBi was constructed to monitor AChE activity with sensitivity and selectivity. Given the inhibition of OPs on AChE activity, a biosensor was further developed by integrating Pd@PtBi with AChE to detect OPs, capitalizing on the cascade amplification strategy. The OP biosensor achieved a detection limit as low as 0.06 ng mL, exhibiting high sensitivity and anti-interference ability. This work is promising for the construction of nanozymes with high activity and specificity, as well as the development of nanozyme-based colorimetric biosensors.
迫切需要灵敏和准确的测定法来监测乙酰胆碱酯酶（AChE）活性和有机磷农药（OPs），这是保障人类健康和保护生态系统的必要条件。由于其成本效益高、操作简便和快速响应，基于纳米酶的比色法已广泛应用于 AChE 活性和 OPs 的测定。然而，合理设计具有高活性和特异性的纳米酶仍然是一个巨大的挑战。本文成功合成了痕量 Bi 掺杂核壳 Pd@Pt 介孔纳米球（Pd@PtBi），表现出良好的过氧化物酶样活性和特异性。由于痕量铋的掺入，Pd@PtBi 的过氧化物酶样性能比 Pd@Pt 提高了 4 倍以上。此外，未发现 Pd@PtBi 的氧化酶样和过氧化氢酶样活性有显著提高，这可防止 O 的干扰和不必要的底物 HO 的消耗。基于硫代胆碱的阻断作用，构建了一种利用 Pd@PtBi 监测 AChE 活性的比色检测平台，具有灵敏度和选择性。由于 OPs 对 AChE 活性的抑制作用，进一步通过将 Pd@PtBi 与 AChE 集成来开发 OP 生物传感器，利用级联放大策略。OP 生物传感器的检测限低至 0.06ng mL，表现出高灵敏度和抗干扰能力。这项工作有望用于构建具有高活性和特异性的纳米酶，并开发基于纳米酶的比色生物传感器。
