基于NaCl高效聚集纳米金的比色适配体传感器检测多菌灵
Colorimetric aptasensor for carbendazim determination based on the salt-induced aggregation of gold nanoparticles

植物体和水体中残留的多菌灵通过食物链进入生物体,最终对生物体健康造成威胁,已经引起了社会的广泛关注。现有的检测方法虽然具有一定的灵敏度和精确性,但往往需要昂贵的大型设备、专业的技术人员和较长的检测时间,因此建立快速、高效的检测方法具有重要的现实意义。在本文中,我们使用标记的多菌灵特异性适配体作为传感探针,NaCl溶液作为聚集诱导剂,纳米金粒子作为颜色指示剂,开发了一种比色适配体传感器用于检测水溶液中的多菌灵。在没有多菌灵时,纳米金颗粒被多菌灵适配体包裹,在NaCl溶液中依然维持分散。当多菌灵存在时,多菌灵适配体与多菌灵特异性结合形成稳定的复合物,此时,溶液中裸露的纳米金在NaCl的作用下聚集,整个体系从红色变为蓝色。该比色法的检测限低至2.3 nmol/L,线性检测范围为2.3~800 nmol/L。加标水样中多菌灵的平均回收率为96.3%~111.2%,相对标准偏差为1.5%~8.9%。该比色适配体传感器操作简单,检测时间短,仪器要求低,因此具有在水环境中快速检测多菌灵的潜力。
Carbendazim (CBZ) residues in plant and water bodies enter the organisms through food chain,and ultimately pose a threat to the health of organisms,which has aroused widespread concern in the society.Although the existing methods for CBZ detection have certain sensitivity and accuracy,they often need expensive large-scale equipment,professional technicians and long detection time.Therefore,it has great practical significance to establish a fast and efficient method for CBZ detection.In this paper,we developed a colorimetric aptasensor for CBZ determination in aqueous solution using label-free CBZ-specific aptamer,NaCl and gold nanoparticles (AuNPs) as sensing probe,aggregation inducer and color indicator respectively.In the absence of CBZ,AuNPs were wrapped by CBZ aptamer and maintained dispersed in NaCl solution basically.In the presence of CBZ,CBZ aptamer could specifically combine with CBZ to form stabilized complex,the AuNPs were released by aptamer and aggregated under the influence of NaCl.The color of the solution changes from red to blue.This colorimetric assay has a detection limit as low as 2.3 nmol/L,a linear range from 2.3 to 800 nmol/L.It was applied to determine CBZ in water samples with recoveries in the range of 96.3%-111.2%,and the relative standard deviation is 1.5%-8.9%.The colorimetric aptasensor is simple,convenient,rapid and low cost,so it holds potential for CBZ detection in environmental water samples.