title: A pivot-hinge-style DNA immobilization method with adaptable surface concentration based on oligodeoxynucleotide-phosphorothioate chemisorption on gold surfaces.
abstract: The chemisorption of oligodeoxynucleotide phosphorothioate (s-oligo) is reported. A series of s-oligo DNAs was designed for use as capture probe DNA molecules. The s-oligo DNAs consist of the K-ras gene (5'-GGA GCT GGT GGC-3') and a dodecamer deoxyriboadenosine, both of which lie on either side of an s-oligo DNA sequence. By primarily focusing on the capture probe DNA having five-successive s-oligo sequences, e37, the immobilization chemistry of e37 was examined; atomic force microscopy achieved the direct visualization of individual molecules on Au(111) substrates, while a series of surface analyses, including IR, ellipsometry, and microgravimetry, showed that the s-oligo functional groups played a pivotal role in the surface-adlayer through the gold-thiol interaction. Interestingly, the amount of immobilization showed a definite relationship with the number of s-oligo linkages introduced, which should be important to regulate the concentration of the capture probe DNA molecules on the surface. Some preliminary studies using ferrocene-modified complementary sequences indicated that electrochemical labeling and readouts were possible.
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, Kyushu University, Motooka, Nishi, Fukuoka, Japan.
authors.forename: Hisao
authors.initials: H
authors.lastname: Yoshinaga
authors.forename: Koji
authors.initials: K
authors.lastname: Nakano
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Soh
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Ishimatsu
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Imato
mesh_terms: D000327:Adsorption; D004247:DNA / Q000737:chemistry* / Q000235:genetics; D006046:Gold / Q000737:chemistry*; D009693:Nucleic Acid Hybridization; D054735:Phosphorothioate Oligonucleotides / Q000737:chemistry* / Q000235:genetics; D013499:Surface Properties
chemical_list: D054735:Phosphorothioate Oligonucleotides; D006046:Gold; D004247:DNA