以阿尔新蓝为低背景信号探针的Pb^(2+)电化学传感器  

An electrochemical Pb^(2+) sensor using Alcian blue as a low background signal probe

作　　者：刘先鑫 高彩 倪健聪 汪庆祥 LIU Xianxin;GAO Cai;NI Jiancong;WANG Qinxiang(School of Chemistry,Chemical Engineering and Environment,Minnan Normal University,Zhangzhou,Fujian 363000,China)

机构地区：[1]闽南师范大学化学化工与环境学院,福建漳州363000

出　　处：《闽南师范大学学报（自然科学版）》2024年第3期84-93,共10页Journal of Minnan Normal University：Natural Science

基　　金：国家自然科学基金项目(21275127,22376089);福建省自然科学基金项目(2018J01435)。

摘　　要：基于电活性探针阿尔新蓝8GX(AB)与G-四联体-Pb^(2+)(G4-Pb^(2+))复合物的亲合作用,以AB为指示探针构建了一种特异性检测Pb^(2+)并具有低背景响应特点的电化学传感器.首先将末端修饰巯基的G4序列通过Au-S键组装到金电极表面,当目标分析物(Pb^(2+))不存在时,AB不与G4发生作用,因此,电极表面观察不到任何法拉第信号;而当Pb^(2+)存在时,其特异性诱导G4从自由链状态折叠为刚性G4-Pb^(2+)结构,并可通过π-π共轭作用将AB吸附在电极表面,从而产生一个可测的法拉第信号.基于此,该传感器可实现对Pb^(2+)的低背景检测.最佳实验条件下的定量分析结果表明,以AB信号探针的传感器能在浓度范围4.9~39μmol/L内对Pb^(2+)进行检测.根据3倍信噪比获得检测限为0.13μmol/L.该方法具有良好的特异性,可用于河水和自来水等不同水样中Pb^(2+)的检测.A novel electrochemical Pb^(2+)sensor with low background response has been constructed based on the specific affinity between the electroactive Alcian blue(AB)and G-quadruplex-Pb^(2+)(G4-Pb^(2+)).First,the G4 sequence with terminal thiol modification was assembled onto the gold electrode surface through Au-S bonding.When the target analyte(Pb^(2+))does not exist,AB does not interact with the G4 molecule,and no Faraday signal is observed on the electrode surface.Nevertheless,in the presence of Pb^(2+),it specifically induces the conformational change of the G4 from free coil situation to a rigid G4-Pb^(2+)structure,which can adsorb AB onto the electrode surface throughπ-πconjugation,thereby generating a measurable Faraday signal.Based on this,the sensor can realize the low background electrochemical detection of Pb^(2+).The quantitative analysis results under optimal experimental conditions indicate that the sensor,using AB as a signal probe,can detect Pb^(2+)within a concentration range of 4.9 to 39μmol/L.The detection limit,based on a signal-to-noise ratio of 3,is 0.13μmol/L.The method has good specificity and can be used for the detection of Pb^(2+)in tap and river water samples.

关 键 词：电化学传感器 G-四联体 铅离子 核酸适体 阿尔新蓝 

分 类 号：O614[理学—无机化学]