Chip and solution detection of DNA hybridization using a luminescent zwitterionic polythiophene derivative

Abstract

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.

Highly Water‐Soluble Thermally Responsive Poly(thiophene)‐Based Brushes

“…As the result of efforts to extend the unique optical and electrical properties of substituted poly(thiophene)s (PTs) [2][3][4] to aqueous media [5,6] and strategies for developing chromismbased PT materials that respond to biological analytes, [7][8][9][10][11] significant advances in the fabrication of water-soluble PTs have occurred. Water-soluble PTs possessing cationic side chains were recently used in the specific detection of DNA hybridization events, [10] nucleic acids, [12] and human thrombin.…”

Single-base Mutation Detection Using Neutravidin-modified Polystyrene Nanoparticle Aggregation

“…For these purposes, several methods using DNA-conjugated materials have recently been reported. [1][2][3][4][5][6][7][8] In these methods, the recognition of a DNA sequence relies on hybridization with probe DNA.…”

Poly-and oligothiophenes : Optical probes for multimodal fluorescent assessment of biological processes

“…This conformational flexibility of the conjugated backbone is based on non-covalently interactions with the biomolecule of interest and is used, for example, in protein sensing applications [38], [39]. Polythiophenes, the probes that are used extensively in this thesis, have great ability to undergo conformational alterations and are widely used to detect conformational changes in proteins [38], [40], synthetic peptides [41], [42] as well as for DNA detection [43]. It is this conformational induced optical phenomena that is utilized for the studies in this thesis and these thiophene-based fluorescent reporters will be discussed in the following sections.…”

“…The initial LCP was POWT [13], a zwitterionic probe that was able to detect peptide conformational changes from random coil to a four-helix bundle [41]. POWT has also shown to be able to follow DNA hybridisation [43], conformational changes of calmodulin upon binding to calcium [48] and is also capable of staining fixed human fibroblasts [49]. POMT was the second original LCP [50] and the third one, which has been used extensively, is PTAA [51].…”