Fast label-free DNA detection using self-signal amplifying fluorescent polymer bioconjugates

POLY 440

Kangwon Lee, kangwonl@umich.edu, Ching-Chin Pun, Laura K. Povlich, and Jinsang Kim. Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109
We describe a bio/-synthetic sensory polymer-DNA bioconjugate method for DNA detection. Synthetically, water soluble conjugated poly(p-phenyleneethynylene) (PPE) was prepared and, by using a simple method, was successfully conjugated to DNA molecules. Single stranded DNA was coupled at the end of the polymer chains and energy emitted from the polymer was efficiently transferred to fluorescent dye labeled to complementary DNA after DNA/DNA hybridization. Therefore, the Förster type energy transfer (FRET) mechanism worked successfully. In addition, we also coupled molecular beacons to conjugated polymer. Conventional molecular beacons are comprised of DNA hairpin structures with a dye at one end and a quencher at the other end. We replaced the monomeric dye with conjugated polymer to develop label-free and self-signal amplifying polymer-beacons and also demonstrated effective detections.