Bioconjugated Quantum Dots for In Vivo Molecular and Cellular Imaging

Departments of Biomedical Engineering and Chemistry, Emory University and Georgia Institute of Technology, Atlanta, GA 30322, USA.
Advanced Drug Delivery Reviews (Impact Factor: 15.04). 09/2008; 60(11):1226-40. DOI: 10.1016/j.addr.2008.03.015
Source: PubMed


Semiconductor quantum dots (QDs) are tiny light-emitting particles on the nanometer scale, and are emerging as a new class of fluorescent labels for biology and medicine. In comparison with organic dyes and fluorescent proteins, they have unique optical and electronic properties, with size-tunable light emission, superior signal brightness, resistance to photobleaching, and broad absorption spectra for simultaneous excitation of multiple fluorescence colors. QDs also provide a versatile nanoscale scaffold for designing multifunctional nanoparticles with both imaging and therapeutic functions. When linked with targeting ligands such as antibodies, peptides or small molecules, QDs can be used to target tumor biomarkers as well as tumor vasculatures with high affinity and specificity. Here we discuss the synthesis and development of state-of-the-art QD probes and their use for molecular and cellular imaging. We also examine key issues for in vivo imaging and therapy, such as nanoparticle biodistribution, pharmacokinetics, and toxicology.

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Available from: Shuming Nie, Nov 28, 2014
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    • "These Qdots are then crosslinked to hydrothermally treated chitosan to create a piggyback style, nontoxic, multifunctional probe in a one-step process by using CNBr chemistry. In this cross-linking step, several ligands are also attached to chitosan, including folic acid[5,252627(FA, targeting motif), polyethylene glycol (PEG dispersing agent) and fluorescein isothiocyanate (FITC, dye for particle tracking). FITC is bound to the chitosan to track the particles in their " OFF " state. "

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    • "Quantum dots: Quantum dots are nanocrystals of a semiconductor material, ranging from the size of 2-10 nm (Smith et al., 2008). Due to the high surface to volume ratio of these particles, they exhibit fluorescent properties. "
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