title: Electrical switching of DNA monolayers investigated by surface plasmon resonance.
abstract: The switching of DNA monolayers between a "lying" and a "standing" state initiated by applying electric field, and the subsequent DNA hybridization at different states were investigated in a contactless, label-free mode by surface plasmon resonance (SPR) technique. The results showed that the strength of the electric field and surface coverage could influence the switching of DNA monolayers. In addition, it was found that DNA hybridization efficiency could be enhanced or decreased when DNA probes stood straight up or lay flat on the gold surface, depending on the potential of the gold substrate. The enhancement of DNA hybridization efficiency reached the maximum when surface coverage reached 5.87 x 10(12) molecules/cm(2) and the potential of gold substrate was more negative than -0.7 V (versus ITO-coated glass). The research may be helpful for the construction of sensitive biosensors, biochips, and nanoscale electronic devices.
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Bio-Nano Technology Engineering Research Center of Hunan Province, Changsha, People's Republic of China.
authors.forename: Xiaohai
authors.initials: X
authors.lastname: Yang
authors.forename: Qing
authors.initials: Q
authors.lastname: Wang
authors.forename: Kemin
authors.initials: K
authors.lastname: Wang
authors.forename: Weihong
authors.initials: W
authors.lastname: Tan
authors.forename: Jing
authors.initials: J
authors.lastname: Yao
authors.forename: Huimin
authors.initials: H
authors.lastname: Li
mesh_terms: D001483:Base Sequence; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D004247:DNA / Q000737:chemistry*; D018076:DNA, Complementary / Q000235:genetics; D004563:Electrochemistry; D006046:Gold; D009693:Nucleic Acid Hybridization; D020349:Surface Plasmon Resonance; D013499:Surface Properties
chemical_list: D020099:Coated Materials, Biocompatible; D018076:DNA, Complementary; D006046:Gold; D004247:DNA