Chip and solution detection of DNA hybridization using a luminescent zwitterionic polythiophene derivative.
Electronic polymers in aqueous media may offer bioelectronic detection of biospecific interactions. Here we report a fluorometric DNA hybridization detection method based on non-covalent coupling of DNA to a water-soluble zwitterionic polythiophene derivative. Introduction of a single-stranded oligonucleotide will induce a planar polymer and aggregation of the polymer chains, detected as a decrease of the intensity and a red-shift of the fluorescence. On addition of a complementary oligonucleotide, the intensity of the emitted light is increased and blue-shifted. The detection limit of this method is at present approximately 10(-11) moles. The method is highly sequence specific, and a single-nucleotide mismatch can be detected within five minutes without using any denaturation steps. The interaction with DNA and the optical phenomena persists when the polymer is deposited and patterned on a surface. This offers a novel way to create DNA chips without using covalent attachment of the receptor or labelling of the analyte.
Nilsson
K Peter R
KP
Biomolecular and Organic Electronics, IFM, Linköping University, SE-581 83 Linköping, Sweden. petni@ifm.liu.se
Inganäs
Olle
O
D004247:DNA / Q000032:analysis* / Q000737:chemistry; D017404:In Situ Hybridization, Fluorescence / Q000379:methods; D008163:Luminescent Measurements; D009693:Nucleic Acid Hybridization / Q000379:methods*; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation / Q000379:methods*; D011108:Polymers / Q000737:chemistry*; D013876:Thiophenes / Q000737:chemistry*
D011108:Polymers; D013876:Thiophenes; C066730:polythiophene; D004247:DNA