title: Catalytic Hairpin Assembly-Programmed DNA Three-Way Junction for Enzyme-Free and Amplified Electrochemical Detection of Target DNA.
abstract: DNA three-way junctions (DNA 3WJ) have been widely used as important building blocks for the construction of DNA architectures and dynamic assemblies. Herein, we describe for the first time a catalytic hairpin assembly-programmed DNA three-way junction (CHA-3WJ) strategy for the enzyme-free and amplified electrochemical detection of target DNA. It takes full advantage of the target-catalyzed hairpin assembly-induced proximity effect of toehold and branch-migration domains for the ingenious execution of the strand displacement reaction to form the DNA 3WJ on the electrode surface. A low detection limit of 0.5 pM with an excellent selectivity was achieved for target DNA detection. The developed CHA-3WJ strategy also offers distinct advantages of simplicity in probe design and biosensor fabrication, as well as enzyme-free operation. Thus, it opens a promising avenue for applications in bioanalysis, design of DNA-responsive devices, and dynamic DNA assemblies.
authors.affiliation: Key Laboratory of Sensor Analysis of Tumor Marker, Ministry of Education, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, No. 53 Rd. Zhengzhou, Qingdao, Shandong, 266042, China. sliu@qust.edu.cn.
authors.forename: Shufeng
authors.initials: S
authors.lastname: Liu
authors.affiliation: Key Laboratory of Sensor Analysis of Tumor Marker, Ministry of Education, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, No. 53 Rd. Zhengzhou, Qingdao, Shandong, 266042, China.
authors.forename: Wenji
authors.initials: W
authors.lastname: Wei
authors.affiliation: Key Laboratory of Sensor Analysis of Tumor Marker, Ministry of Education, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, No. 53 Rd. Zhengzhou, Qingdao, Shandong, 266042, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Liu
authors.affiliation: Key Laboratory of Sensor Analysis of Tumor Marker, Ministry of Education, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, No. 53 Rd. Zhengzhou, Qingdao, Shandong, 266042, China. wangli@qust.edu.cn.
authors.forename: Li
authors.initials: L
authors.lastname: Wang
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D004247:DNA / Q000032:analysis*; D021881:DNA, Catalytic / Q000737:chemistry; D055664:Electrochemical Techniques / Q000379:methods; D061925:Immobilized Nucleic Acids / Q000737:chemistry*; D057230:Limit of Detection; D009690:Nucleic Acid Conformation
chemical_list: D021881:DNA, Catalytic; D061925:Immobilized Nucleic Acids; D004247:DNA
keywords: DNA biosensors; DNA three-way junction; electrochemical detection; strand displacement; target catalyzed hairpin assembly