Annals of Biomedical Engineering

, Volume 34, Issue 1, pp 3–14 | Cite as

Engineering Luminescent Quantum Dots for In Vivo Molecular and Cellular Imaging

  • Andrew M. Smith
  • Gang Ruan
  • Matthew N. Rhyner
  • Shuming Nie

Semiconductor quantum dots are luminescent nanoparticles that are under intensive development for use as a new class of optical imaging contrast agents. Their novel properties such as optical tunability, improved photostability, and multicolor light emission have opened new opportunities for imaging living cells and in vivo animal models at unprecedented sensitivity and spatial resolution. Combined with biomolecular engineering strategies for tailoring the particle surfaces at the molecular level, bioconjugated quantum dot probes are well suited for imaging single-molecule dynamics in living cells, for monitoring protein–protein interactions within specific intracellular locations, and for detecting diseased sites and organs in deep tissue. In this article, we describe the engineering principles for preparing high-quality quantum dots and for conjugating the dots to biomolecular ligands. We also discuss recent advances in using quantum dots for in vivo molecular and cellular imaging.


Nanoparticles Nanotechnology Fluorescence Living cells Living animals Molecular imaging Cytotoxicity Cationic peptides Bioconjugation Dynamic light scattering 



fluorescence resonance energy transfer


polyethylene glycol


quantum dot


reticuloendothelial system




trioctylphosphine oxide



This work was supported by grants from the National Institutes of Health (P20 GM072069, R01 CA108468, and R01 GM058173), the U.S. Department of Energy Genomes to Life Program, and the Georgia Cancer Coalition (GCC). One of the authors (A.M.S.) acknowledges the Whitaker Foundation for generous fellowship support.


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Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • Andrew M. Smith
    • 1
  • Gang Ruan
    • 1
  • Matthew N. Rhyner
    • 1
  • Shuming Nie
    • 1
    • 2
  1. 1.Departments of Biomedical Engineering and ChemistryEmory University and Georgia Institute of TechnologyAtlantaUSA
  2. 2.Departments of Biomedical Engineering and ChemistryEmory University and Georgia Institute of TechnologyAtlantaUSA

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