Pharmaceutical Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran; Department of Medicinal Chemistry, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
Research Institute of Sciences and New Technology, Mashhad, Iran.
Anal Chim Acta. 2018 Aug 22;1020:110-115. doi: 10.1016/j.aca.2018.02.066. Epub 2018 Mar 10.
Herein, a novel colorimetric aptasensor was introduced for detection of cocaine based on the formation of three-way junction pockets on the surfaces of gold nanoparticles (AuNPs) and the catalytic activity of the surfaces of AuNPs. Simplicity and detection of cocaine in a short time (only 35 min) are some of the unique features of the proposed sensing strategy. In the presence of cocaine, triple-fragment aptamer (TFA) forms on the surfaces of AuNPs, leading to a significant decrease of the catalytic activity of AuNPs and the color of samples remains yellow. In the absence of target, TFA does not form on the surfaces of AuNPs and 4-Nitrophenol, as a colorimetric agent, has more access to the surfaces of AuNPs, resulting in the reduction of 4-Nitrophenol and the color of sample changes from yellow to colorless. The sensing strategy showed good specificity, a limit of detection (LOD) of 440 pM and a dynamic range over 2-100 nM. The sensing method was also successfully applied to detect cocaine in spiked human serum samples with recovery of 94.71-98.63%.
本文提出了一种基于金纳米粒子（AuNPs）表面三链结口袋的形成和 AuNPs 表面催化活性的新型比色适体传感器，用于可卡因的检测。该传感策略具有一些独特的特点，如简单、可卡因的快速检测（仅需 35 分钟）。在可卡因存在的情况下，三片段适体（TFA）在 AuNPs 表面形成，导致 AuNPs 的催化活性显著降低，样品颜色保持黄色。在没有目标的情况下，TFA 不会在 AuNPs 表面形成，而 4-硝基苯酚作为比色试剂，更易于接触到 AuNPs 表面，导致 4-硝基苯酚还原，样品颜色从黄色变为无色。该传感策略表现出良好的特异性，检测限（LOD）为 440 pM，动态范围为 2-100 nM 之间。该传感方法还成功地应用于检测加标人血清样品中的可卡因，回收率为 94.71-98.63%。
