title: A DNA-stabilized silver nanoclusters/graphene oxide-based platform for the sensitive detection of DNA through hybridization chain reaction.
abstract: A silver nanoclusters (AgNCs)/graphene oxide (GO)-based fluorescence sensor was developed for label-free DNA detection through hybridization chain reaction (HCR). A DNA sequence associated with the human immunodeficiency virus (HIV) was selected as a model target. Two DNA probes, hairpin probe 1 (H1) and hairpin probe 2 (H2), were partially complementary. GO was used as an adsorption material to capture the hairpin probes and a selective fluorescence quencher was used to reduce the background signal. Upon addition of AgNO3and NaBH4, the AgNCs were synthesized at the terminals of the H1and H2probes. In the absence of target DNA (THIV), hybridization chain reaction (HCR) could not be triggered due to the stability of H1and H2probes. The hairpin probe-protected AgNCs attached to the GO surface, efficiently quenching fluorescence of the AgNCs. Therefore, the system showed very low background. In presence of THIV, the target triggered the chain-like assembly of H1and H2through HCR, generating a long chain of H1and H2complexes. The HCR product (AgNCs nanowires) could not be adsorbed on the surface of GO; hence, it generated a strong fluorescent signal based on the concentration of the target. Under the optimized conditions, the detection limit of the fluorescence sensor was 1.18nM, and hence it can be applied to clinical samples.
authors.affiliation: Department of Chemistry, Taizhou University, Jiaojiang 318000, China; College of Sciences, Northeastern University, Shenyang 110819, China. Electronic address: zsqneu@126.com.
authors.forename: Siqi
authors.initials: S
authors.lastname: Zhang
authors.affiliation: College of Sciences, Northeastern University, Shenyang 110819, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Wang
authors.affiliation: Department of Chemistry, Taizhou University, Jiaojiang 318000, China.
authors.forename: Kai-Bin
authors.initials: KB
authors.lastname: Li
authors.affiliation: Department of Chemistry, Taizhou University, Jiaojiang 318000, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Shi
authors.affiliation: Department of Chemistry, Taizhou University, Jiaojiang 318000, China.
authors.forename: Wen-Ping
authors.initials: WP
authors.lastname: Jia
authors.affiliation: Department of Chemistry, Taizhou University, Jiaojiang 318000, China.
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Chen
authors.affiliation: College of Sciences, Northeastern University, Shenyang 110819, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Sun
authors.affiliation: Department of Chemistry, Taizhou University, Jiaojiang 318000, China. Electronic address: hdm@tzc.edu.cn.
authors.forename: De-Man
authors.initials: DM
authors.lastname: Han
mesh_terms: D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods; D015342:DNA Probes / Q000737:chemistry / Q000235:genetics; D004279:DNA, Viral / Q000032:analysis* / Q000235:genetics; D005456:Fluorescent Dyes / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D006678:HIV / Q000235:genetics / Q000302:isolation & purification*; D015658:HIV Infections / Q000097:blood / Q000821:virology; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry*; D008958:Models, Molecular; D009693:Nucleic Acid Hybridization / Q000379:methods*; D010087:Oxides / Q000737:chemistry; D012834:Silver / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods
chemical_list: D015342:DNA Probes; D004279:DNA, Viral; D005456:Fluorescent Dyes; D010087:Oxides; D012834:Silver; D006108:Graphite
keywords: DNA detection; Fluorescence sensor; Graphene oxide; Hybridization chain reaction; Silver nanoclusters