title: Highly selective and sensitive electrochemical biosensor for ATP based on the dual strategy integrating the cofactor-dependent enzymatic ligation reaction with self-cleaving DNAzyme-amplified electrochemical detection.
abstract: A dual strategy that combines the adenosine triphosphate (ATP)-dependent enzymatic ligation reaction with self-cleaving DNAzyme-amplified electrochemical detection is employed to construct the biosensor. In this design, the methylene blue-labeled hairpin-structured DNA was self-assembled onto a gold electrode surface to prepare the modified electrode through the interaction of Au-S bond. In the procedure of ATP-dependent ligation reaction, when the specific cofactor ATP was added, the two split oligonucleotide fragments of 8-17 DNAzyme were linked by T4 DNA ligase and then released to hybridize with the labeled hairpin-structured DNA substrate. The linked 8-17 DNAzyme catalyzes the cleavage of the hairpin-structured substrate by the addition of Zn(2+), causing the methylene blue which contains high electrochemical activity to leave the surface of the gold electrode, therefore generating a dramatic decrease of electrochemical signal. The decrease of peak current was readily measured by square wave voltammetry and a relatively low detection limit (0.05 nM) was obtained with a linear response range from 0.1 to 1000 nM. By taking advantage of the highly specific cofactor dependence of the DNA ligation reaction, the proposed ligation-induced DNAzyme cascades demonstrate ultrahigh selectivity toward the target cofactor ATP. A catalytic and molecular beacons strategy is further adopted to amplify the electrochemical signal detection achieved by cycling and regenerating the 8-17 DNAzyme to realize enzymatic multiple turnover, thus one DNAzyme can catalyze the cleavage of several hairpin-structured substrates, which improves the sensitivity of the newly designed electrochemical sensing system.
authors.affiliation: Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Lu
authors.affiliation: Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
authors.forename: Jing Cao
authors.initials: JC
authors.lastname: Si
authors.affiliation: Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
authors.forename: Zhong Feng
authors.initials: ZF
authors.lastname: Gao
authors.affiliation: Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China.
authors.forename: Jing Lei
authors.initials: JL
authors.lastname: Lei
authors.affiliation: Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China. Electronic address: luohq@swu.edu.cn.
authors.forename: Hong Qun
authors.initials: HQ
authors.lastname: Luo
authors.affiliation: Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China. Electronic address: linb@swu.edu.cn.
authors.forename: Nian Bing
authors.initials: NB
authors.lastname: Li
mesh_terms: D000255:Adenosine Triphosphate / Q000737:chemistry / Q000302:isolation & purification*; D015374:Biosensing Techniques; D004247:DNA / Q000737:chemistry*; D011088:DNA Ligases / Q000737:chemistry; D021881:DNA, Catalytic / Q000737:chemistry*; D006801:Humans; D057230:Limit of Detection; D009693:Nucleic Acid Hybridization
chemical_list: D021881:DNA, Catalytic; D000255:Adenosine Triphosphate; D004247:DNA; D011088:DNA Ligases
keywords: 8-17 DNAzyme; ATP detection; Electrochemical biosensor; Signal amplification; T4 DNA ligase