title: A G-quadruplex-based Label-free Fluorometric Aptasensor for Adenosine Triphosphate Detection.
abstract: A G-quadruplex-based, label-free fluorescence assay was demonstrated for the detection of adenosine triphosphate (ATP). A double-stranded DNA (dsDNA), hybridized by ATP-aptamer and its complementary sequence, was employed as a substrate for ATP binding. SYBR Green I (SG I) was a fluorescent probe and exonuclease III (Exo III) was a nuclease to digest the dsDNA. Consequently, in the absence of ATP, the dsDNA was inset with SG I and was digested by Exo III, resulting in a low background signal. In the presence of ATP, the aptamer in dsDNA folded into a G-quadruplex structure that resisted the digestion of Exo III. SG I was inserted into the structure, showing high fluorescence. Owing to a decrease of the background noise, a high signal-to-noise ratio could be obtained. This sensor can detect ATP with a concentration ranging from 50 μM to 5 mM, and possesses a capacity for the sensitive determination of other targets.
authors.affiliation: State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University.
authors.forename: Li Juan
authors.initials: LJ
authors.lastname: Li
authors.forename: Xue
authors.initials: X
authors.lastname: Tian
authors.forename: Xiang Juan
authors.initials: XJ
authors.lastname: Kong
authors.forename: Xia
authors.initials: X
authors.lastname: Chu
mesh_terms: D000255:Adenosine Triphosphate / Q000032:analysis* / Q000378:metabolism; D052157:Aptamers, Nucleotide / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D055162:Biocatalysis; D015374:Biosensing Techniques / Q000379:methods*; D004247:DNA / Q000737:chemistry; D005090:Exodeoxyribonucleases / Q000378:metabolism; D054856:G-Quadruplexes; D057230:Limit of Detection; D008958:Models, Molecular; D009693:Nucleic Acid Hybridization
chemical_list: D052157:Aptamers, Nucleotide; D000255:Adenosine Triphosphate; D004247:DNA; D005090:Exodeoxyribonucleases; C020133:exodeoxyribonuclease III