title: Label-free electrochemical impedance genosensor based on 1-aminopyrene/graphene hybrids.
abstract: In this work, we proposed a novel simple protocol for preparing 1-aminopyrene/graphene (ApG) hybrids for fabricating label-free electrochemical impedance genosensor. Graphene, with the structure of a single-atom-thick sheet of sp(2)-bonded carbon atoms, was anchored to 1-aminopyrene (1-Ap) with the pyrenyl group viaπ-stacking interaction. The morphology, conductivity, and interaction of ApG hybrids were characterized by transmission electron microscopy (TEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), UV-visible (UV-vis) and fluorescence spectra. The amino-substituted oligonucleotide probe was conjugated to 1-Ap by the cross-linker glutaraldehyde. The DNA hybridization reaction of oligonucleotide probe with target DNA was monitored by EIS. Under optimum conditions, the proposed biosensor exhibited high sensitivity and a low detection limit for detecting the complementary oligonucleotide. The target oligonucleotide could be quantified in a wide range of 1.0 × 10(-12) to 1.0 × 10(-8) M with good linearity (R = 0.9900) and low detection limit of 4.5 × 10(-13) M (S/N = 3).
authors.affiliation: College of Sciences, Shanghai University, Shanghai 200444, PR China. luoliqw@yahoo.com.cn
authors.forename: Li-Qiang
authors.initials: LQ
authors.lastname: Luo
authors.forename: Zhao
authors.initials: Z
authors.lastname: Zhang
authors.forename: Ya-Ping
authors.initials: YP
authors.lastname: Ding
authors.forename: Dong-Mei
authors.initials: DM
authors.lastname: Deng
authors.forename: Xiao-Li
authors.initials: XL
authors.lastname: Zhu
authors.forename: Zhen-Xin
authors.initials: ZX
authors.lastname: Wang
mesh_terms: D004247:DNA / Q000032:analysis* / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D009693:Nucleic Acid Hybridization / Q000379:methods; D009841:Oligonucleotides / Q000737:chemistry*; D011721:Pyrenes / Q000737:chemistry*
chemical_list: D009841:Oligonucleotides; D011721:Pyrenes; D006108:Graphite; D004247:DNA; C004482:1-aminopyrene