摘要
该文以特殊设计的DNA序列为捕获探针,以G-四链体-血红素复合物作为信号分子,利用链式反应实现目标DNA的灵敏检测。在目标DNA存在时,捕获探针与目标DNA相互识别,同时目标DNA能与辅助探针发生连续的链式反应,从而在电极表面引入大量G-四链体结构。血红素存在下,G-四链体可与血红素结合形成具有很强电化学信号的G-四链体-血红素复合物。用差分脉冲伏安法(DPV)扫描得到的电化学信号与体系中的目标DNA浓度存在对应关系,从而实现对目标DNA的检测。在各组分浓度最适的情况下,电流响应值与目标DNA浓度在0.01~10 pmol/L内具有良好的线性关系,检出限可达8 fmol/L。该传感器灵敏度高、特异性好,具有良好的应用前景。
In this study,a DNA biosensor was constructed for the sensitive detection of target DNA by chain reaction,with a specially-designed DNA sequence as capture probe and a G-quadruplex-hemin complex as signal molecule.In the presence of target DNA,the capture DNA and the target DNA could recognize each other,while the target DNA could have a continuous chain reaction with the assistant probe,leading to the formation of a large number of G-quadruplex on the electrode surface.In the presence of hemin,the G-quadruplex combines with the hemin to form a G-quadruplex-hemin complex,which emits a strong electrochemical signal.Therefore, the detection of target DNA could be realized as the electrochemical signal obtained by differential pulse voltammetry(DPV) has a corresponding relationship with concentration of the target DNA in the system.Under the optimal conditions for the concentration of each component,the DPV current response has a good linear relationship with the target DNA concentration in the range of 0.01-10 pmol/L,and the minimum detection limit reaches to 8 fmol/L.With the advantages of high sensitivity and good specificity,the sensor has a good application prospect.
作者
孙延修
孙笑凡
SUN Yan-xiu;SUN Xiao-fan(Department of Basic Courses,Shenyang Institute of Technology,Fushun 113122,China;Wuxi Yaoming Biotechnology Co.,Ltd,Wuxi 214122,China)
出处
《分析测试学报》
CAS
CSCD
北大核心
2020年第6期774-778,共5页
Journal of Instrumental Analysis
基金
中国烟草总公司标准项目(2018QBZ08)。
作者简介
通讯作者:孙笑凡,硕士,研究方向:电化学生物传感器,E-mail:sunxiaofan2020@126.com。
