title: Tryptamine functionalized reduced graphene oxide for label-free DNA impedimetric biosensing.
abstract: A novel simple protocol of synthesizing tryptamine-functionalized reduced graphene oxide (TRA-rGO) was proposed to fabricate label-free electrochemical impedance DNA biosensor. TRA was anchored to rGO with its indole ring via π-stacking interaction. The morphology, conductivity and interaction of TRA-rGO were characterized by atomic force microscopy, high resolution transmission electron microscopy, cyclic voltammetry, electrochemical impedance spectroscopy (EIS) as well as Raman and fluorescence spectroscopy. The amino-substituted oligonucleotide probe was conjugated to TRA by cross-linker glutaraldehyde for preparing an electrochemical biosensing platform. The DNA hybridization reaction of oligonucleotide probe with target DNA was monitored by EIS. Under optimum conditions, the proposed biosensor exhibited high sensitivity and low detection limit for detecting complementary oligonucleotide. The target oligonucleotide could be quantified in a wide range of 1.0 × 10(-12)-1.0 × 10(-7)M with low detection limit of 5.2 × 10(-13)M (S/N=3).
authors.affiliation: College of Sciences, Shanghai University, Shanghai 200444, PR China.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: College of Sciences, Shanghai University, Shanghai 200444, PR China. Electronic address: luck@shu.edu.cn.
authors.forename: Liqiang
authors.initials: L
authors.lastname: Luo
authors.affiliation: Laboratory of Biosensing Technology, School of Life Sciences, Shanghai University, Shanghai 200444, PR China.
authors.forename: Guifang
authors.initials: G
authors.lastname: Chen
authors.affiliation: College of Sciences, Shanghai University, Shanghai 200444, PR China.
authors.forename: Yaping
authors.initials: Y
authors.lastname: Ding
authors.affiliation: College of Sciences, Shanghai University, Shanghai 200444, PR China.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Deng
authors.affiliation: Division of Physical Biology and Bioimaging Center, Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, PR China.
authors.forename: Chunhai
authors.initials: C
authors.lastname: Fan
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation*; D004247:DNA / Q000032:analysis* / Q000235:genetics*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006108:Graphite / Q000737:chemistry*; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA / Q000295:instrumentation*; D013194:Staining and Labeling; D014363:Tryptamines / Q000737:chemistry*
chemical_list: D010087:Oxides; D014363:Tryptamines; C030820:tryptamine; D006108:Graphite; D004247:DNA
keywords: DNA biosensor; Electrochemical impedance; Reduced graphene oxide; Tryptamine