title: Use of β-cyclodextrin-tethered cationic polymer based fluorescence enhancement of pyrene and hybridization chain reaction for the enzyme-free amplified detection of DNA.
abstract: Herein, we proposed an enzyme-free strategy for the amplified detection of DNA by combining the efficient fluorescence enhancement capability of a β-cyclodextrin-tethered cationic polymer (cationic polyβ-CD) to pyrene with the amplification capability of target DNA triggered hybridization chain reaction (HCR). Cationic polyβ-CD with positive charge was synthesized. Two hairpin probes, H1 and H2, were employed in the system and the pyrene-labelled H2 was chosen as the signal unit. The pyrene attached on the sticky end of H2 was flexible and there was strong electrostatic interaction between cationic polyβ-CD and negatively-charged H2, so pyrene could easily enter the cavity of CD that is tethered on the cationic polymer, accompanied by significant fluorescence enhancement. Once target DNA was introduced, HCR was triggered to form a rigid long dsDNA polymer with pyrene attached on it. The pyrene was hardly able to enter the cavity of cationic polyβ-CD because of steric hindrance, leading to a weak fluorescent signal. Owing to the efficient pyrene fluorescence enhancement of cationic polyβ-CD and the amplified capability of HCR, an enzyme-free sensitive detection of target DNA was achieved with a detection limit of 0.1 nM and high selectivity.
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Key Laboratory for Bio-Nanotechnology and Molecular Engineering of Hunan Province, Hunan University, Changsha 410082, China. yangxiaohai@hnu.edu.cn kmwang@hnu.edu.cn and School of Science, Anhui Agricultural University, Hefei 230036, China.
authors.forename: Chunxia
authors.initials: C
authors.lastname: Song
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Key Laboratory for Bio-Nanotechnology and Molecular Engineering of Hunan Province, Hunan University, Changsha 410082, China. yangxiaohai@hnu.edu.cn kmwang@hnu.edu.cn.
authors.forename: Bingjie
authors.initials: B
authors.lastname: Li
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Key Laboratory for Bio-Nanotechnology and Molecular Engineering of Hunan Province, Hunan University, Changsha 410082, China. yangxiaohai@hnu.edu.cn kmwang@hnu.edu.cn.
authors.forename: Xiaohai
authors.initials: X
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Key Laboratory for Bio-Nanotechnology and Molecular Engineering of Hunan Province, Hunan University, Changsha 410082, China. yangxiaohai@hnu.edu.cn kmwang@hnu.edu.cn.
authors.forename: Kemin
authors.initials: K
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Key Laboratory for Bio-Nanotechnology and Molecular Engineering of Hunan Province, Hunan University, Changsha 410082, China. yangxiaohai@hnu.edu.cn kmwang@hnu.edu.cn.
authors.forename: Qing
authors.initials: Q
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Key Laboratory for Bio-Nanotechnology and Molecular Engineering of Hunan Province, Hunan University, Changsha 410082, China. yangxiaohai@hnu.edu.cn kmwang@hnu.edu.cn.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Key Laboratory for Bio-Nanotechnology and Molecular Engineering of Hunan Province, Hunan University, Changsha 410082, China. yangxiaohai@hnu.edu.cn kmwang@hnu.edu.cn.
authors.forename: Jin
authors.initials: J
authors.lastname: Huang
mesh_terms: D004247:DNA / Q000032:analysis* / Q000737:chemistry*; D057230:Limit of Detection; D009693:Nucleic Acid Hybridization; D011108:Polymers / Q000737:chemistry*; D011721:Pyrenes / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D047392:beta-Cyclodextrins / Q000737:chemistry*
chemical_list: D011108:Polymers; D011721:Pyrenes; D047392:beta-Cyclodextrins; D004247:DNA; C030984:pyrene