title: A label-free fluorescent adenosine triphosphate biosensor via overhanging aptamer-triggered enzyme protection and target recycling amplification.
abstract: Herein, a label-free fluorescent adenosine triphosphate (ATP) aptasensor is fabricated with a DNA hairpin and an overhanging aptamer. In the presence of ATP, the overhanging sequences of the aptamer may form preferred substrates of exo III, and thus trigger the enzyme-assisted amplification, which results in the release of G-rich sequences. Free G-rich sequences subsequently generate an enhanced flourescent signal by binding with thioflavin T. However, if ATP is absent, the overhanging sequence can induce steric hindrance and protect the DNA hairpin against the digestion of exo III, significantly reducing the noise of this biosensor. Accordingly, the signal-to-noise ratio of the sensing system is greatly improved, which ensures the desirable analytical performance of the proposed aptasensor both in pure samples and real samples.
authors.affiliation: Jiangsu Collaborative Innovation Center of Biomedical Functional Materials and Jiangsu Key Laboratory of Biofunctional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, P. R. China. daizhihuii@ninu.edu.cn.
authors.forename: Zhaoyin
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Jiangsu Collaborative Innovation Center of Biomedical Functional Materials and Jiangsu Key Laboratory of Biofunctional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, P. R. China. daizhihuii@ninu.edu.cn.
authors.forename: Jian
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Jiangsu Collaborative Innovation Center of Biomedical Functional Materials and Jiangsu Key Laboratory of Biofunctional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, P. R. China. daizhihuii@ninu.edu.cn.
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Dai
mesh_terms: D000255:Adenosine Triphosphate / Q000737:chemistry*; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D052160:Benzothiazoles; D015374:Biosensing Techniques; D005090:Exodeoxyribonucleases / Q000737:chemistry; D006801:Humans; D013844:Thiazoles / Q000737:chemistry
chemical_list: D052157:Aptamers, Nucleotide; D052160:Benzothiazoles; D013844:Thiazoles; C009462:thioflavin T; D000255:Adenosine Triphosphate; D005090:Exodeoxyribonucleases