Share Email Print

Journal of Biomedical Optics • Open Access

Europium-quantum dot nanobioconjugates as luminescent probes for time-gated biosensing
Author(s): Piotr J. Cywiński; Tommy Hammann; Dominik Hühn; Wolfgang J. Parak; Niko Hildebrandt; Hans-Gerd Löhmannsröben

Paper Abstract

Nanobioconjugates have been synthesized using cadmium selenide quantum dots (QDs), europium complexes (EuCs), and biotin. In those conjugates, long-lived photoluminescence (PL) is provided by the europium complexes, which efficiently transfer energy via Förster resonance energy transfer (FRET) to the QDs in close spatial proximity. As a result, the conjugates have a PL emission spectrum characteristic for QDs combined with the long PL decay time characteristic for EuCs. The nanobioconjugates synthesis strategy and photophysical properties are described as well as their performance in a time-resolved streptavidin-biotin PL assay. In order to prepare the QD-EuC-biotin conjugates, first an amphiphilic polymer has been functionalized with the EuC and biotin. Then, the polymer has been brought onto the surface of the QDs (either QD655 or QD705) to provide functionality and to make the QDs water dispersible. Due to a short distance between EuC and QD, an efficient FRET can be observed. Additionally, the QD-EuC-biotin conjugates’ functionality has been demonstrated in a PL assay yielding good signal discrimination, both from autofluorescence and directly excited QDs. These newly designed QD-EuC-biotin conjugates expand the class of highly sensitive tools for bioanalytical optical detection methods for diagnostic and imaging applications.

Paper Details

Date Published: 2 July 2014
PDF: 8 pages
J. Biomed. Opt. 19(10) 101506 doi: 10.1117/1.JBO.19.10.101506
Published in: Journal of Biomedical Optics Volume 19, Issue 10
Show Author Affiliations
Piotr J. Cywiński, Univ. Potsdam (Germany)
Fraunhofer Institute for Applied Polymer Research (Germany)
Tommy Hammann, Univ. Potsdam (Germany)
Fraunhofer Institute for Applied Polymer Research (Germany)
Dominik Hühn, Philipps-Univ. Marburg (Germany)
Wolfgang J. Parak, Philipps-Univ. Marburg (Germany)
Niko Hildebrandt, Univ. of Paris-South (France)
Hans-Gerd Löhmannsröben, Univ. Potsdam (Germany)

© SPIE. Terms of Use
Back to Top