Li Peng, Zhan Haonan, Tao Sijian, Xie Zhuohao, Huang Jiahao
School of Biomedical Engineering, Southern Medical University, Guangzhou , China.
Department of Critical Care Medicine, Affiliated Hospital of Guangdong Medical University, Zhanjiang , China.
Front Bioeng Biotechnol. 2023 Mar 3;11:1165724. doi: 10.3389/fbioe.2023.1165724. eCollection 2023.
Biosensors always respond to the targets of interest in a specific manner, employing biological or bio-mimic recognition elements such as antibodies and aptamers. Inspired by target recognition in nature, an aptamer-mediated, gold nanoparticle-based sensing approach is developed in this work for effective determination of malathion. The sensing system consists of negatively charged aptamer probes, and polycationic proteins, protamine, as well as exceptional colorimetric nanoprobes, barely gold nanoparticles (AuNPs). Protamine molecules bound to aptamer probes hinder the aggregation of AuNPs, while no such inhibition is maintained when aptamer-specific malathion is introduced into the solution, thus leading to the solution colour change from red to blue observable by the naked eye. The assay is accomplished a mix-and-measure step within 40 min with a detection limit as low as 1.48 μg/L (3σ/s rule). The assay method also exhibits high selectivity and good applicability for the quantification of malathion in tap water with recovery rates of 98.9%-109.4%. Additionally, the good detection accuracy is also confirmed by the high-performance liquid chromatography method. Therefore, the non-enzymatic, label- and device-free characteristics make it a robust tool for malathion assay in agricultural, environmental, and medical fields.
生物传感器总是以特定方式对感兴趣的目标作出响应，采用生物或生物模拟识别元件，如抗体和适体。受自然界中目标识别的启发，本研究开发了一种基于适体介导的金纳米颗粒传感方法，用于有效测定马拉硫磷。传感系统由带负电荷的适体探针、聚阳离子蛋白鱼精蛋白以及特殊的比色纳米探针（即金纳米颗粒，AuNPs）组成。与适体探针结合的鱼精蛋白分子会阻碍金纳米颗粒的聚集，而当将适体特异性的马拉硫磷引入溶液中时，这种抑制作用就会消失，从而导致溶液颜色从红色变为蓝色，肉眼即可观察到。该检测在40分钟内通过一个混合测量步骤完成，检测限低至1.48μg/L（3σ/s规则）。该检测方法对自来水中马拉硫磷的定量分析还具有高选择性和良好的适用性，回收率为98.9%-109.4%。此外，高效液相色谱法也证实了该检测方法具有良好的检测准确性。因此，这种非酶促、无标记和无设备的特性使其成为农业、环境和医学领域中马拉硫磷检测的有力工具。
