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Quantum dot-based resonance energy transfer and its growing appliaction in biology. Phys Chem Chem Phys

US Naval Research Laboratory, Center for Bio/Molecular Science and Engineering, Code 6910, and Division of Optical Sciences, Code 5611, 4555 Overlook Ave, S.W. Washington DC, 20375, USA.
Physical Chemistry Chemical Physics (Impact Factor: 4.2). 02/2009; 11(1):17-45. DOI: 10.1039/b813919a
Source: PubMed

ABSTRACT We provide an overview of the progress made in the past few years in investigating fluorescence resonance energy transfer (FRET) using semiconductor quantum dots (QDs) and the application of QD-based FRET to probe specific biological processes. We start by providing some of the pertinent conceptual elements involved in resonance energy transfer, and then discuss why the Förster dipole-dipole mechanism applies to QD fluorophores. We then describe the unique QD photophysical properties of direct relevance to FRET and summarize the main advantages offered, along with some of the limitations encountered by QDs as exciton donors and/or acceptors. Next we describe the overall progress made and discuss a few representative examples where QD-based FRET sensing of specific biological processes has been demonstrated. We also detail some of the advances of single molecule FRET using QD-conjugates and highlight the unique information that can be extracted. We conclude by providing an assessment of where QD-based FRET investigations may be evolving in the near future.

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    • "Fluorescence-activated cell sorting (FACS), the most popular application of flow cytometry, requires damage-free staining or labeling of cells to permit further processing after the initial sort. Förster resonance energy transfer (FRET)-based sensing might be capable of supplying more-dynamic information regarding biological processes [2] [3] in comparison with standard fluorescent staining or labeling, but a robust pair of fluorescent molecules (a donor and an acceptor) is required. Fluorescence-lifetime imaging (FLIM), which is based on related principles, has also been developed for imaging of living cells [4]. "
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    • "Recently semiconductor nanocrystals with specific optical properties were developed that can be coupled with functional units isolated from biological organisms in establishing hybrid systems for different applications (for a review, see [2]). Among the various types of hybrid system design the coupling between quantum dots (QDs) and pigmentprotein complexes is of special interest in aiming at constructing systems for photovoltaics where QDs act as efficient light harvesting units. "
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