title: An electrochemical DNA sensor without electrode pre-modification.
abstract: We present a non-modification electrochemical DNA sensing strategy, which used Potential-Assisted Au-S Deposition and a clamp-like DNA probe. The dual-hairpin probe DNA was tagged with a methylene blue (MB) at the 3' terminal and a thiol at the 5' terminal., Without being hybridized with target DNA, the loop of probe prevented the thiol from reaching the bare gold electrode surface with an applied potential., After hybridization with the target DNA, the probe' s loop-stem structure opened through two distinct and sequential events, which led to the formation of a triplex DNA structure. Then the thiol easily contacted with electrode and resulted in potential-assisted Au-S self-assembly. Electrochemical signals of MB were measured by differential pulse voltammetry (DPV) and used for target quantitative detection. This strategy offered a detection limit down to 2.3pM. and an inherently high specificity for detecting even single mismatch.
authors.affiliation: Department of Pharmacy, JiangXi University of Traditional Chinese Medicine, JiangXi 330004, China.
authors.forename: Nian
authors.initials: N
authors.lastname: Hong
authors.affiliation: Department of Pharmacy, JiangXi University of Traditional Chinese Medicine, JiangXi 330004, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Cheng
authors.affiliation: Department of Pharmacy, JiangXi University of Traditional Chinese Medicine, JiangXi 330004, China.
authors.forename: BingGuo
authors.initials: B
authors.lastname: Wei
authors.affiliation: Department of Pharmacy, JiangXi University of Traditional Chinese Medicine, JiangXi 330004, China.
authors.forename: ChaDan
authors.initials: C
authors.lastname: Chen
authors.affiliation: Department of Pharmacy, JiangXi University of Traditional Chinese Medicine, JiangXi 330004, China.
authors.forename: Ling Ling
authors.initials: LL
authors.lastname: He
authors.affiliation: Department of Pharmacy, JiangXi University of Traditional Chinese Medicine, JiangXi 330004, China.
authors.forename: DeRong
authors.initials: D
authors.lastname: Kong
authors.affiliation: The Research Center of Chinese Medicine Resource and National Medicine of Jiang Xi University of Traditional Chinese Medicine, JiangXi 330004, China.
authors.forename: JinXiang
authors.initials: J
authors.lastname: Ceng
authors.affiliation: Department of Pharmacy, JiangXi University of Traditional Chinese Medicine, JiangXi 330004, China. Electronic address: cuihanfeng@126.com.
authors.forename: Han-Feng
authors.initials: HF
authors.lastname: Cui
authors.affiliation: Department of Pharmacy, JiangXi University of Traditional Chinese Medicine, JiangXi 330004, China. Electronic address: fanhao11@aliyun.com.
authors.forename: Hao
authors.initials: H
authors.lastname: Fan
mesh_terms: D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods*; D004247:DNA / Q000032:analysis* / Q000737:chemistry; D015342:DNA Probes / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D006046:Gold / Q000737:chemistry; D057230:Limit of Detection; D009690:Nucleic Acid Conformation; D009693:Nucleic Acid Hybridization / Q000379:methods*; D013438:Sulfhydryl Compounds / Q000737:chemistry
chemical_list: D015342:DNA Probes; D013438:Sulfhydryl Compounds; C051802:triplex DNA; D006046:Gold; D004247:DNA
keywords: Clamp-like DNA probe; Electrochemical DNA sensor; Homogenous sensing; Non-modification; Potential-Assisted