An electrochemical aptasensor based on enzyme linked aptamer assay
An electrochemical aptasensor based on enzyme linked aptamer assay
复制标题
基于酶联适体检测的电化学适体传感器
DOI：
10.1016/j.bios.2011.10.046
复制
发表时间：
2012-01-15
影响因子：
12.6
通讯作者：
Zhang, Xin-Xiang
中科院分区：
文献类型：
--
作者：
Zhang, De-Wen;Sun, Cui-Jin;Zhang, Xin-Xiang
适体是一种人工合成的功能性寡核酸，能与靶分子发生高亲和力、高特异性的相互作用。基于核酸适体片段与可卡因之间的亲和作用，建立了核酸适体片段/可卡因构型检测可卡因的酶联核酸适体分析法（ELAA）。将抗可卡因适体切割成两段，一段组装在金电极表面，另一段在3 '端修饰生物素，可进一步用链霉亲和素-辣根过氧化物酶（SA-HRP）标记。当与可卡因结合时，在H2 O2存在下，在电极上形成的HRP标记的适体片段/可卡因复合物将增加氢醌（HQ）的还原电流。用微分脉冲伏安法（DPV）研究了该电化学适体传感器的灵敏度和特异性。结果表明，DPV信号的变化可以灵敏地检测可卡因，其动态范围为0.1 μ M ~ 50 μ M，检测限可达20 nM（S/N = 3）。该适体传感器具有灵敏度高、背景电流小等优点。此外，一个新的配置ELAA只需要一个单一的适配体序列的构建，它可以推广到检测不同类型的目标，通过切割的适配体成两个合适的片段。(C)2011爱思唯尔有限公司版权所有。
An aptamer is an artificial functional oligonucleic acid, which can interact with its target molecule with high affinity and specificity. Enzyme linked aptamer assay (ELAA) is developed to detect cocaine using aptamer fragment/cocaine configuration based on the affinity interaction between aptamer fragments with cocaine. The aptasensor was constructed by cleaving anticocaine aptamer into two fragments: one was assembled on a gold electrode surface, while the other was modified with biotin at 3'-end, which could be further labelled with streptavidin-horseradish peroxidase (SA-HRP). Upon binding with cocaine, the HRP-labelled aptamer fragment/cocaine complex formed on the electrode would increase the reduction current of hydroquinone (HQ) in the presence of H2O2. The sensitivity and the specificity of the proposed electrochemical aptasensor were investigated by differential pulse voltammetry (DPV). The results indicated that the DPV signal change could be used to sensitively detect cocaine with the dynamic range from 0.1 mu M to 50 mu M and the detection limit down to 20 nM (S/N = 3). The proposed aptasensor has the advantages of high sensitivity and low background current. Furthermore, a new configuration for ELAA requiring only a single aptamer sequence is constructed, which can be generalized for detecting different kinds of targets by cleaving the aptamers into two suitable segments. (C) 2011 Elsevier B.V. All rights reserved.