title: Detection of Pb2+in Aqueous Solution by Using a DNA-modified Microcantilever.
abstract: We developed a novel Pb2+-sensor based on a microcantilever that was modified with a specific Pb2+-dependent DNAzyme molecule. This microcantilever sensor could detect Pb2+sensitively and selectively in an aqueous solution. Upon complexation with Pb2+, the DNAzyme duplex unwinded and formed a G-quadruplex conformation, which led to an increase of repulsion between the DNAzyme molecules and a subsequent bending of the microcantilever. This microcantilever sensor could be regenerated, flowing through a strong Pb2+chelator, 1,4,7,10-tetraazacyclododecane- 1,4,7,10-tetraacetic acid. The detection limit of the microcantilever sensor for Pb2+ions is as low as 10-8M. The microcantilever sensor also exhibited a high selectivity to Pb2+over other metal ions such as Mg2+, Fe3+, Zn2+, Ca2+, and Cd2+.
authors.affiliation: Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences and Graduate University of Chinese Academy of Sciences.
authors.forename: Rong-Peng
authors.initials: RP
authors.lastname: Peng
authors.forename: Ling-Bao
authors.initials: LB
authors.lastname: Xing
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Wang
authors.forename: Cheng-Juan
authors.initials: CJ
authors.lastname: Wu
authors.forename: Bin
authors.initials: B
authors.lastname: Chen
authors.forename: Hai-Feng
authors.initials: HF
authors.lastname: Ji
authors.forename: Li-Zhu
authors.initials: LZ
authors.lastname: Wu
authors.forename: Chen-Ho
authors.initials: CH
authors.lastname: Tung
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D021881:DNA, Catalytic / Q000737:chemistry*; D054856:G-Quadruplexes; D007854:Lead / Q000032:analysis*; D012680:Sensitivity and Specificity; D012996:Solutions; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D021881:DNA, Catalytic; D012996:Solutions; D014874:Water Pollutants, Chemical; D007854:Lead