Sensitive fluorescence detection of nucleic acids based on isothermal circular strand-displacement polymerization reaction.
Here we have developed a sensitive DNA amplified detection method based on isothermal strand-displacement polymerization reaction. This method takes advantage of both the hybridization property of DNA and the strand-displacement property of polymerase. Importantly, we demonstrate that our method produces a circular polymerization reaction activated by the target, which essentially allows it to self-detect. Functionally, this DNA system consists of a hairpin fluorescence probe, a short primer and polymerase. Upon recognition and hybridization with the target ssDNA, the stem of the hairpin probe is opened, after which the opened probe anneals with the primer and triggers the polymerization reaction. During this process of the polymerization reaction, a complementary DNA is synthesized and the hybridized target is displaced. Finally, the displaced target recognizes and hybridizes with another probe, triggering the next round of polymerization reaction, reaching a target detection limit of 6.4 x 10(-15) M.
Guo
Qiuping
Q
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China.
Yang
Xiaohai
X
Wang
Kemin
K
Tan
Weihong
W
Li
Wei
W
Tang
Hongxing
H
Li
Huimin
H
D004277:DNA, Single-Stranded / Q000737:chemistry; D004259:DNA-Directed DNA Polymerase; D005456:Fluorescent Dyes / Q000737:chemistry*; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D009693:Nucleic Acid Hybridization / Q000379:methods; D017422:Sequence Analysis, DNA / Q000379:methods*; D013696:Temperature
D004277:DNA, Single-Stranded; D005456:Fluorescent Dyes; D004259:DNA-Directed DNA Polymerase