Chem. J. Chinese Universities ›› 2021, Vol. 42 ›› Issue (3): 745.doi: 10.7503/cjcu20200435

• Analytical Chemistry • Previous Articles     Next Articles

Sensitive and Electrochemical Detection of Telomerase Activity Based on the Signal Amplification of Strand Displacement Reaction

MA Yanrong1, JIANG Shengnan2, JIN Yan2()   

  1. 1.School of Preparatory Education,North Minzu University,Yinchuan 750021,China
    2.Analytical Chemistry for Life Science of Shaanxi Province,School of Chemistry and Chemical Engineering,Shaanxi Normal University,Xi’an 710062,China
  • Received:2020-07-07 Online:2021-03-10 Published:2021-03-08
  • Contact: JIN Yan E-mail:jinyan@snnu.edu.cn
  • Supported by:
    ? Supported by the National Natural Science Foundation of China(21974083);the Fundamental Research Funds for the Central Universities, China(GK 202002002)

Abstract:

An electrochemical method was developed for sensitive detection of telomerase activity based on strand displacement reaction. A ferrocene(Fc)-labeled DNA probe(T-DNA) was designed as signal probe. The thiolated hairpin DNA(H-DNA) was used as capture probe and was self-assembled on the Au electrode surface via Au-S bond. Assisted DNA(A-DNA) partially hybridized with T-DNA to form AT-DNA duplex. In the presence of telomerase, telomerase substrate(TS) primer was elongated by adding multiple TTAGGG repeats at its 3′ terminal. The elongated DNA hybridized with A-DNA to displace T-DNA which can hybridize with H-DNA. As a result, the Fc tags are close to the Au electrode surface, producing an electrochemical signal. One elongated DNA can displace multiple T-DNAs, leading to the enrichment of Fc onto the Au electrode for signal amplification. Based on this, the peak current is linearly related with the number of HeLa cells in the range of 5―100 cells, and detection limit is down to 5 HeLa cells. Therefore, it provides a simple and sensitive approach for detecting telomerase activity.

Key words: Telomerase, Strand displacement reaction, Electrochemistry

CLC Number: 

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