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Reagentless ultrasensitive specific DNA array detection based on responsive polymeric biochips.

Ahmed Najari·Hoang Anh Ho·Jean-François Gravel·Philippe Nobert·Denis Boudreau·Mario Leclerc
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Abstract

Self-assembled molecular structures immobilized on solid substrates and composed of fluorophore-tagged oligonucleotide probes and an optical polymeric transducer were investigated for the trace level detection of DNA target molecules. Rapid and efficient energy transfer between the polymeric transducer and fluorophores within the molecular aggregates leads to a massive intrinsic amplification of the fluorescence signal and to the label-free detection of as little as 300 DNA molecules, with the specificity required for the detection of single-nucleotide mismatches. This capacity for attomolar detection levels while the sensing structures are attached onto solid supports could lead to the development of biochip platforms for fast and simple PCR-free multitarget DNA detection.

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Base Pair MismatchBiosensing TechniquesDNAFluorescent DyesOligonucleotide Array Sequence AnalysisOligonucleotide ProbesPolymorphism, Single NucleotideSensitivity and SpecificitySpectrometry, FluorescenceJournal ArticleResearch Support, Non-U.S. Gov't

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Ahmed Najari, Hoang Anh Ho, Jean-François Gravel, Philippe Nobert, Denis Boudreau, Mario Leclerc. 2006-11-15. Reagentless ultrasensitive specific DNA array detection based on responsive polymeric biochips.. https://doi.org/10.1021/ac061650%2B

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