title: Fenton's reagent-tuned DNA-templated fluorescent silver nanoclusters as a versatile fluorescence probe and logic device.
abstract: A label-free strategy based on the Fenton reaction with DNA-templated silver nanoclusters (DNA-Ag NCs) as a probe is demonstrated for the sequential detection of Cu(2+), ascorbic acid (AA) and H(2)O(2). Cu(2+) causes a structural change of the DNA template in DNA-Ag NCs to resist the environmental quenching and emit stronger fluorescence. The addition of AA in the presence of Cu(2+) results in a further fluorescence increase of the DNA-Ag NCs. Interestingly, an even higher fluorescence enhancement is recorded by introducing Cu(2+) into the DNA-Ag NCs-AA probing system. The fluorescence turn-on probe offers detection limits of 3 nM for Cu(2+) and 7 nM for AA. Thereafter, the addition of H(2)O(2) generates hydroxyl radicals from the Fenton reaction, which induces cleavage of the DNA template, leading to fluorescence quenching of the DNA-Ag NCs. This facilitates H(2)O(2) detection. Moreover, based on the DNA-templated fluorescent silver nanoclusters and Fenton reaction, a multiple logic gate system, including AND and a three-input logic gate, is constructed, with Cu(2+), AA and H(2)O(2) as inputs, and the fluorescence intensity of the DNA-Ag NCs probe as output.
authors.affiliation: Research Center for Analytical Sciences, College of Sciences, Northeastern University, Box 332, Shenyang 110819, China.
authors.forename: Li-Pei
authors.initials: LP
authors.lastname: Zhang
authors.forename: Xiao-Xing
authors.initials: XX
authors.lastname: Zhang
authors.forename: Bo
authors.initials: B
authors.lastname: Hu
authors.forename: Li-Ming
authors.initials: LM
authors.lastname: Shen
authors.forename: Xu-Wei
authors.initials: XW
authors.lastname: Chen
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Wang
mesh_terms: D001205:Ascorbic Acid / Q000032:analysis / Q000737:chemistry; D001483:Base Sequence; D039301:Computers, Molecular; D003300:Copper / Q000032:analysis / Q000737:chemistry; D004247:DNA / Q000737:chemistry* / Q000235:genetics; D005456:Fluorescent Dyes / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D008128:Logic; D053768:Metal Nanoparticles / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*
chemical_list: C045076:Fenton's reagent; D005456:Fluorescent Dyes; D012834:Silver; D003300:Copper; D004247:DNA; D006861:Hydrogen Peroxide; D007501:Iron; D001205:Ascorbic Acid