title: Electrochemical interrogation of DNA monolayers on gold surfaces.
abstract: In this report, we systematically investigated DNA immobilization at gold surfaces with electrochemical techniques. Comparative cyclic voltammetric and chronocoulometric studies suggested that DNA monolayers immobilized at gold surfaces were not homogeneous. Nonspecific Au-DNA interactions existed even with the treatment of mercaptohexanol, which was known to competitively remove loosely bound DNA at gold surfaces. While both thiolated and nonthiolated DNA formed monolayers on gold surfaces, their hybridization abilities were distinctly different. In contrast to thiolated DNA probes, nonthiolated DNA probes immobilized at gold surfaces were essentially nonhybridizable. The experimental results presented here might be useful for the design of high-performance electrochemical DNA sensors.
authors.affiliation: Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.
authors.forename: Ruojun
authors.initials: R
authors.lastname: Lao
authors.forename: Shiping
authors.initials: S
authors.lastname: Song
authors.forename: Haiping
authors.initials: H
authors.lastname: Wu
authors.forename: Lihua
authors.initials: L
authors.lastname: Wang
authors.forename: Zhizhou
authors.initials: Z
authors.lastname: Zhang
authors.forename: Lin
authors.initials: L
authors.lastname: He
authors.forename: Chunhai
authors.initials: C
authors.lastname: Fan
mesh_terms: D004247:DNA / Q000737:chemistry*; D004563:Electrochemistry; D006046:Gold / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D006046:Gold; D004247:DNA