title: DNA-triggered dye transfer on a quantum dot.
abstract: Nucleic acid-templated reactions are frequently explored tools in nucleic acid diagnosis. To enable a separation-free DNA detection, the reactive probe molecules require conjugation with reporter groups that provide measurable changes of an observable parameter upon reaction. A widely used, generic read-out method is based on fluorescence resonance energy transfer (FRET) between two appended dyes. Yet, spectral cross-talk usually limits the achievable enhancements of the FRET signal in DNA-directed chemistries. We describe a DNA-triggered transfer reaction which provides for strong increases of a fluorescent signal caused by FRET. The method may involve DNA- and PNA-based probes and is based upon a proximity-triggered transfer reaction which leads to the covalent fixation of a fluorescence dye on the surface of a quantum dot (QD). The transfer reaction brings the dye closer to the QD than hybridization alone. The resulting FRET signal is a specific monitor of the reaction and allows efficient discrimination of single base mismatched templates. Of note, the 35-fold increase of the FRET signal is measured at 310 nm apparent Stokes shift and turnover in template provides a means for signal amplification.
authors: Humboldt-Universität zu Berlin , Institut für Chemie, Brook-Taylor-Str. 2, 12489 Berlin, Germany.
authors: Julia
authors: J
authors: Michaelis
authors: Gerbrand Jan
authors: GJ
authors: van der Heden van Noort
authors: Oliver
authors: O
authors: Seitz
mesh_terms: D001483:Base Sequence; D019187:Cadmium Compounds / Q000737:chemistry*; D004247:DNA / Q000032:analysis*; D031541:Fluorescence Resonance Energy Transfer; D005456:Fluorescent Dyes / Q000737:chemistry*; D008969:Molecular Sequence Data; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry*; D013440:Sulfides / Q000737:chemistry*; D013499:Surface Properties; D017967:Zinc Compounds / Q000737:chemistry*
chemical_list: D019187:Cadmium Compounds; D005456:Fluorescent Dyes; D018036:Selenium Compounds; D013440:Sulfides; D017967:Zinc Compounds; D004247:DNA; C058667:cadmium selenide; C031238:zinc sulfide