title: Direct DNA hybridization detection based on the oligonucleotide-functionalized conductive polymer.
abstract: Electrochemical methods for DNA hybridization detection have many advantages that are very fast to detect hybridization and can be directly applied for a portable DNA sensor. In this paper, an electrochemical method to directly detect DNA hybridization was developed on the basis of a new conductive polymer, which was polymerized on the glassy carbon electrode with a terthiophene monomer having a carboxyl group (3'-carboxyl-5,2',5',2"-terthiophene). The ss-DNA probe was made by chemically bonding an amine-linked C6 alkyl group to the 5' terminus of oligonucleotide (19-mer). The probe moiety was immobilized on the polymer through covalent bonding with a catalyst, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide. A difference in admittance was observed before and after hybridization as a result of the reduction of the resistance after hybridization. The highest difference in admittance was observed around 1 kHz before and after hybridization. Hybridization amounts of end two-base and center one-base mismatched sequences were obtained only in a 14.3% response when compared to that for the complementary matched sequence.
authors.forename: T Y
authors.initials: TY
authors.lastname: Lee
authors.forename: Y B
authors.initials: YB
authors.lastname: Shim
mesh_terms: D020137:Base Pair Mismatch; D015374:Biosensing Techniques / Q000379:methods*; D015342:DNA Probes / Q000138:chemical synthesis* / Q000737:chemistry / Q000592:standards; D004563:Electrochemistry; D008839:Microelectrodes; D009693:Nucleic Acid Hybridization; D009841:Oligonucleotides / Q000032:analysis*; D011108:Polymers / Q000737:chemistry
chemical_list: D015342:DNA Probes; D009841:Oligonucleotides; D011108:Polymers