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Direct DNA hybridization detection based on the oligonucleotide-functionalized conductive polymer.

T Y Lee·Y B Shim
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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.

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Base Pair MismatchBiosensing TechniquesDNA ProbesElectrochemistryMicroelectrodesNucleic Acid HybridizationOligonucleotidesPolymersLetterResearch Support, Non-U.S. Gov't

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T Y Lee, Y B Shim. 2001-11-15. Direct DNA hybridization detection based on the oligonucleotide-functionalized conductive polymer.. https://doi.org/10.1021/ac015572w

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