基于适配体亲吻复合物构建电化学阻抗传感器用于腺苷的检测  

Detection of Adenosine Using Electrochemical Impedance Biosensor Based on Aptamer-Kissing Complexes

作　　者：陈秋香[1,2] 赵燕苹 吴冬枝 蔡淑贤[1] 夏垚坤 陈梅[1] 陈敬华[1] 

机构地区：[1]福建医科大学药学院药物分析学系,福建福州350108 [2]晋江市疗养院,福建泉州362200

出　　处：《分析测试学报》2015年第9期1081-1086,共6页Journal of Instrumental Analysis

基　　金：国家自然科学基金资助项目(21105012;21375017);福建省自然科学基金杰出青年人才项目(2013J06003);福建省科技厅重点项目(2013Y0045);福建省高等学校新世纪优秀人才支持计划(JAl3130);福建省卫生系统中青年骨干人才培养项目(2014-ZQN-ZD-26)

摘　　要：基于适体探针（Aptamer probes,AP）和发卡探针（Hairpin probes,HP）在腺苷（Adenosine,AD）存在时的新型结合模式,构建了一种非标记型电化学阻抗传感器用于腺苷的检测。固定在电极表面的AP在腺苷存在时会折叠成发夹结构,其发夹的环部与HP的环部部分互补杂交,二者通过环-环相互作用（类似人类“亲吻”行为）形成一个“亲吻型适配体复合物”,由于复合物的空间位阻作用,使得电极的阻抗信号明显变大。相反,腺苷不存在时,AP呈舒展状态,无法与HP结合成稳定的“亲吻”结构,电极的阻抗信号无明显变化。以电子传递电阻值作为响应信号来检测腺苷,最佳实验条件下,在5~1 000 nmol/L浓度范围内,电阻值与腺苷浓度的对数呈良好的线性关系,检出限达0.6 nmol/L。另外,该传感器具有良好的选择性,有望应用于临床实际样本中腺苷的检测。A label-free electrochemical impedance biosensor was fabricated for adenosine detection based on a new combining mode of aptamer probes（ AP） and hairpin probes（ HP） in the presence of adenosine（ AD）. AP was first modified on the surface of the electrode. In the presence of AD,AP was folded into hairpin structure,the loop of the hairpin hybrids with complementary loop of HP to form a ＂kissing aptamer complex＂,through the loop- loop interactions（ being similar to ＂kissing＂behavior of the human）. Due to the steric effect of the complex,the impedance signal of the electrode was obviously increased. On the contrary,in the absence of adenosine, AP was unfolded,which was unable to combine with HP into a stable ＂kissing＂ structure. The impedance signal did not change significantly. In this study,the electron transfer resistance values before and after combination were used for the detection of adenosine. Under the optimized conditions,a good linear relationship was obtained between resistance value and logarithm of concentration of AD in the range of 5-1 000 nmol/L. The limit of detection for adenosine is as low as 0. 6 nmol/L. In addition,the sensor has a good selectivity. Guanosine,cytidine and uridine did not influence the detection of adenosine.The sensor is expected to be applied in the detection of adenosine in clinical real samples.

关 键 词：适体 电化学阻抗传感器 亲吻 腺苷 

分 类 号：O657.1[理学—分析化学] Q524[理学—化学]