Toehold-mediated strand displacement reaction-propelled cascade DNAzyme amplifier for microRNA let-7a detection  

作　　者：Na Wang Yongjian Jiang Kunhan Nie Di Li Hui Liu Jian Wang Chengzhi Huang Chunmei Li 

机构地区：[1]Key Laboratory of Luminescence Analysis and Molecular Sensing(Southwest University),Ministry of Education,College of Pharmaceutical Sciences,Southwest University,Chongqing 400715,China [2]The Second Affiliated Hospital of Chongqing Medical University,Chongqing 400010,China

出　　处：《Chinese Chemical Letters》2023年第6期211-214,共4页中国化学快报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(NSFC,Nos.22074124 and 22134005);the fund of Fundamental Research Funds for the Central Universities(No.XDJK2020TY001);Chongqing Talents Program for Outstanding Scientists(No.cstc2021ycjh-bgzxm0178);the Chongqing Graduate Student Scientific Research Innovation Project(No.CYB21119)。

摘　　要：DNAzyme amplifiers have been extensively explored as a useful sensing platform,but single DNAzyme amplifier is limited in biosensing applications by its low sensitivity.Herein,a cascade DNAzyme amplifier was designed by exploiting concurrent amplification cycle principles of toehold-mediated strand displacement reaction(TSDR)and Zn^(2+)-assisted DNAzyme cycle with lower cost and simpler procedures.Compared with single DNAzyme amplifier,the proposed TSDR-propelled cascade DNAzyme amplifier exhibited higher sensitivity by releasing more DNAzyme through TSDR to cleave substrate strand during the DNAzyme cycle.Base on this,let-7a could be sensitively detected in the range of 5-50 nmol/L with a detection limit of 64 pmol/L.Furthermore,the dual signal amplification strategy of the cascade DNAzyme amplifier exhibited excellent selectivity to distinguish single-base mismatched DNA strands,which has been successfully applied to the determination of let-7a in blood serum,showing high promise in early cancer diagnosis.

关 键 词：DNAzyme amplifier Toehold-mediated strand displacement reaction Signal amplification let-7a Cancer marker 

分 类 号：R318[医药卫生—生物医学工程]