title: A label-free electrochemical aptasensor based on graphene oxide/double-stranded DNA nanocomposite.
abstract: A novel label-free electrochemical impedance aptasensor based on a gold nanoparticles/double-stranded DNA-graphene (AuNPs/dsDNA-GO) nanocomposite modified glassy carbon electrode was presented for quantitative determination of thrombin. GO was covalently functionalized with dsDNA via a facile amidation process, and then AuNPs were electrodeposited onto the surface of dsDNA-GO. The morphology, conductivity and interaction of the as-prepared nanocomposites were characterized by scanning electron microscopy, cyclic voltammetry, electrochemical impedance spectroscopy (EIS), Raman and Fourier transform infrared spectroscopy. The thrombin-binding aptamer (TBA) was conjugated to AuNPs via gold-thiol chemistry to construct electrochemical aptasensing platform, and the specific recognition between TBA and thrombin was monitored by EIS. Under optimum conditions, thrombin could be quantified in a wide range of 0.1-100nM (R(2)=0.9960) with low detection limit of 0.06nM (S/N=3).
authors.affiliation: Department of Chemistry, Shanghai University, Shanghai 200444, PR China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Chemistry, Shanghai University, Shanghai 200444, PR China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Chemistry, Shanghai University, Shanghai 200444, PR China.
authors.forename: Yuting
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Shanghai Key Laboratory of High Temperature Superconductors, Department of Physics, Shanghai University, Shanghai 200444, PR China.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Deng
authors.affiliation: Department of Chemistry, Shanghai University, Shanghai 200444, PR China.
authors.forename: Haibo
authors.initials: H
authors.lastname: He
authors.affiliation: Department of Chemistry, Shanghai University, Shanghai 200444, PR China; Shanghai Key Laboratory of High Temperature Superconductors, Department of Physics, Shanghai University, Shanghai 200444, PR China. Electronic address: luck@shu.edu.cn.
authors.forename: Liqiang
authors.initials: L
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, PR China. Electronic address: wangzx@ciac.jl.cn.
authors.forename: Zhenxin
authors.initials: Z
authors.lastname: Wang
mesh_terms: D004247:DNA / Q000235:genetics; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry; D053761:Nanocomposites / Q000737:chemistry*
chemical_list: D006046:Gold; D006108:Graphite; D004247:DNA
keywords: Double-stranded DNA; Electrochemical impedance spectroscopy; Gold nanoparticle; Graphene oxide; Thrombin