title: In situ amplified electrochemical aptasensing for sensitive detection of adenosine triphosphate by coupling target-induced hybridization chain reaction with the assembly of silver nanotags.
abstract: Biomolecular immobilization and construction of the sensing platform are usually crucial for the successful development of a high-efficiency detection system. Herein we report on a novel and label-free signal-amplified aptasensing for sensitive electrochemical detection of small molecules (adenosine triphosphate, ATP, used in this case) by coupling with target-induced hybridization chain reaction (HCR) and the assembly of electroactive silver nanotags. The system mainly consisted of two alternating hairpin probes, a partial-pairing trigger-aptamer duplex DNA and a capture probe immobilized on the electrode. Upon target ATP introduction, the analyte attacked the aptamer and released the trigger DNA, which was captured by capture DNA immobilized on the electrode to form a newly partial-pairing double-stranded DNA. Thereafter, the exposed domain at trigger DNA could be utilized as the initator strand to open the hairpin probes in sequence, and propagated a chain reaction of hybridization events between two alternating hairpins to form a long nicked double-helix. The electrochemical signal derived from the assembled silver nanotags on the nicked double-helix. Under optimal conditions, the electrochemical aptasensor could exhibit a high sensitivity and a low detection limit, and allowed the detection of ATP at a concentration as low as 0.03 pM. Our design showed a high selectivity for target ATP against its analogs because of the high-specificity ATP-aptamer reaction, and its applicable for monitoring ATP in the spiking serum samples. Improtantly, the distinct advantages of the developed aptasensor make it hold a great potential for the development of simple and robust sensing strategies for the detection of other small molecules by controlling the apatmer sequence.
authors.affiliation: Key Laboratory of Analysis and Detection for Food Safety (Ministry of Education & Fujian Province), Institute of Nanomedicine and Nanobiosensing, Department of Chemistry, Fuzhou University, Fuzhou 350108, PR China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Analysis and Detection for Food Safety (Ministry of Education & Fujian Province), Institute of Nanomedicine and Nanobiosensing, Department of Chemistry, Fuzhou University, Fuzhou 350108, PR China.
authors.forename: Youxiu
authors.initials: Y
authors.lastname: Lin
authors.affiliation: Key Laboratory of Analysis and Detection for Food Safety (Ministry of Education & Fujian Province), Institute of Nanomedicine and Nanobiosensing, Department of Chemistry, Fuzhou University, Fuzhou 350108, PR China.
authors.forename: Yuping
authors.initials: Y
authors.lastname: Lin
authors.affiliation: Key Laboratory of Analysis and Detection for Food Safety (Ministry of Education & Fujian Province), Institute of Nanomedicine and Nanobiosensing, Department of Chemistry, Fuzhou University, Fuzhou 350108, PR China. Electronic address: dianping.tang@fzu.edu.cn.
authors.forename: Qiaohua
authors.initials: Q
authors.lastname: Wei
authors.affiliation: Key Laboratory of Analysis and Detection for Food Safety (Ministry of Education & Fujian Province), Institute of Nanomedicine and Nanobiosensing, Department of Chemistry, Fuzhou University, Fuzhou 350108, PR China.
authors.forename: Guonan
authors.initials: G
authors.lastname: Chen
authors.affiliation: Key Laboratory of Analysis and Detection for Food Safety (Ministry of Education & Fujian Province), Institute of Nanomedicine and Nanobiosensing, Department of Chemistry, Fuzhou University, Fuzhou 350108, PR China.
authors.forename: Dianping
authors.initials: D
authors.lastname: Tang
mesh_terms: D000255:Adenosine Triphosphate / Q000032:analysis* / Q000097:blood / Q000737:chemistry; D000818:Animals; D052157:Aptamers, Nucleotide / Q000737:chemistry* / Q000235:genetics; D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods*; D002417:Cattle; D004247:DNA / Q000737:chemistry* / Q000235:genetics; D004563:Electrochemistry; D057230:Limit of Detection; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry*; D009690:Nucleic Acid Conformation; D009693:Nucleic Acid Hybridization; D012834:Silver / Q000737:chemistry*
chemical_list: D052157:Aptamers, Nucleotide; D012834:Silver; D000255:Adenosine Triphosphate; D004247:DNA
keywords: Adenosine triphosphate; Electrochemical aptasensor; Hybridization chain reaction; Label free; Metal silver nanotags