title: Combing DNAzyme with single-walled carbon nanotubes for detection of Pb(II) in water.
abstract: A sensitive and simple assay for the detection of Pb(2+) in aqueous solutions is reported. It takes advantage of the high affinity between single-stranded DNA (ssDNA) and single-walled carbon nanotubes (SWCNT) as well as the capability of SWCNT in fluorescence quenching. Lead(II) catalyzes the cleavage of a fluorescently labeled DNA substrate by a DNAzyme, which releases the single-stranded product to be adsorbed onto a SWCNT. The decrease in fluorescence is proportional to the Pb(2+) concentration. Concentrations as low as 1 nM Pb(2+) in water could be detected and the detection range spans over 5 orders of magnitude. The unique combination of Pb-specific DNAzyme with SWCNT produces a universal, facile and cost-effective sensing platform for lead ions. The concept can be applied to the design of detection assays for other metal ions or small molecules.
authors.affiliation: Department of Chemistry, University of California, Riverside, 92507, USA.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Yao
authors.forename: Jishan
authors.initials: J
authors.lastname: Li
authors.forename: Jeremy
authors.initials: J
authors.lastname: Owens
authors.forename: Wenwan
authors.initials: W
authors.lastname: Zhong
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D021881:DNA, Catalytic / Q000378:metabolism*; D004277:DNA, Single-Stranded / Q000378:metabolism; D004785:Environmental Pollutants / Q000032:analysis*; D005456:Fluorescent Dyes / Q000378:metabolism; D007854:Lead / Q000032:analysis*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D014867:Water / Q000737:chemistry*
chemical_list: D021881:DNA, Catalytic; D004277:DNA, Single-Stranded; D004785:Environmental Pollutants; D005456:Fluorescent Dyes; D037742:Nanotubes, Carbon; D014867:Water; D007854:Lead