title: A label-free fluorescent molecular beacon based on DNA-Ag nanoclusters for the construction of versatile Biosensors.
abstract: In this paper, we developed a simple, low-cost and sensitive DNA sequences detection biosensor based on a label-free molecular beacon (MB) whose DNA hairpin structure terminal has a guanine-rich sequence that can enhance fluorescence of silver nanoclusters (Ag NCs). Without hybridization between hairpin probe and target DNA, the Ag NCs presented bright fluorescence for the proximity of guanine-rich sequences (GRSs). After binding with target DNA, the hairpin shape was destroyed which results in a decrease of the Ag NCs fluorescence intensity. With this biosensor, we detected three disease-related genes that were the human immunodeficiency virus (HIV) gene, hepatitis B virus (HBV) gene and human T-lymphotropic virus type I (HTLV-I) gene. The detection limits based on S/N of 3 were 4.4 nM, 6.8 nM and 8.5 nM for HIV gene, HBV gene and HTLV-I gene, respectively. Our sensor was also of high selectivity and could distinguish even one nucleotide mismatched target.
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China; University of Chinese Academy of Sciences, Beijing 100039, China.
authors.forename: Qiao
authors.initials: Q
authors.lastname: Cao
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China; University of Chinese Academy of Sciences, Beijing 100039, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Teng
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China; University of Chinese Academy of Sciences, Beijing 100039, China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China; University of Chinese Academy of Sciences, Beijing 100039, China; Department of Chemistry and Physics, State University of New York at Stony Brook, New York, NY 11794-3400, USA. Electronic address: ekwang@ciac.jl.cn.
authors.forename: Jin
authors.initials: J
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China; University of Chinese Academy of Sciences, Beijing 100039, China.
authors.forename: Erkang
authors.initials: E
authors.lastname: Wang
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D004279:DNA, Viral / Q000032:analysis* / Q000737:chemistry / Q000235:genetics*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D053768:Metal Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D015336:Molecular Probe Techniques / Q000295:instrumentation; D015335:Molecular Probes / Q000138:chemical synthesis; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA / Q000295:instrumentation*; D012834:Silver / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000295:instrumentation; D013194:Staining and Labeling
chemical_list: D004279:DNA, Viral; D015335:Molecular Probes; D012834:Silver
keywords: DNA detection; Molecular beacons; Silver nanoclusters