title: An exonuclease I-based label-free fluorometric aptasensor for adenosine triphosphate (ATP) detection with a wide concentration range.
abstract: A novel aptamer-based label-free assay for sensitive and selective detection of ATP was developed. This assay employs a new aptamer/fluorescent probe system that shows resistance to exonuclease I (Exo I) digestion upon binding to ATP molecules. In the absence of ATP, the complex between the ATP-binding aptamer (ATP-aptamer) and a DNA binding dye, berberine, is digested upon the addition of exonuclease I, leading to the release of berberine into solution and consequently, quenched berberine fluorescence. In the presence of ATP, the ATP-binding aptamer folds into a G-quadruplex structure that is resistant to Exo I digestion. Accordingly, berberine is protected in the G-quadruplex structure and high fluorescence intensity is observed. As such, based on the fluorescence signal change, a label-free fluorescence assay for ATP was developed. Factors affecting the analysis of ATP including the concentration of ATP-binding aptamer, reaction time, temperature and the concentration of Exo I were comprehensively investigated. Under optimal conditions, the fluorescence intensity of the sensing system displayed a response for ATP in a wide range up to 17.5 mM with a detection limit of 140 nM.
authors.affiliation: Institute of Environmental Science, and School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, PR China. Electronic address: weiyanli@sxu.edu.cn.
authors.forename: Yanli
authors.initials: Y
authors.lastname: Wei
authors.affiliation: Institute of Environmental Science, and School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, PR China.
authors.forename: Yanxia
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Institute of Environmental Science, and School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, PR China.
authors.forename: Huanhuan
authors.initials: H
authors.lastname: Li
authors.affiliation: Institute of Environmental Science, and School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, PR China.
authors.forename: Shaomin
authors.initials: S
authors.lastname: Shuang
authors.affiliation: Institute of Environmental Science, and School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, PR China. Electronic address: dc@sxu.edu.cn.
authors.forename: Chuan
authors.initials: C
authors.lastname: Dong
authors.affiliation: Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States. Electronic address: gwang10@ncsu.edu.
authors.forename: Gufeng
authors.initials: G
authors.lastname: Wang
mesh_terms: D000255:Adenosine Triphosphate / Q000737:chemistry / Q000302:isolation & purification*; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D001599:Berberine / Q000737:chemistry; D015374:Biosensing Techniques; D005090:Exodeoxyribonucleases / Q000737:chemistry*; D005453:Fluorescence; D005470:Fluorometry; D054856:G-Quadruplexes; D057230:Limit of Detection
chemical_list: D052157:Aptamers, Nucleotide; D001599:Berberine; D000255:Adenosine Triphosphate; D005090:Exodeoxyribonucleases; C028450:exodeoxyribonuclease I