In vivo molecular and cellular imaging with quantum dots.
Quantum dots (QDs), tiny light-emitting particles on the nanometer scale, are emerging as a new class of fluorescent probe for in vivo biomolecular and cellular imaging. In comparison with organic dyes and fluorescent proteins, QDs have unique optical and electronic properties: size-tunable light emission, improved signal brightness, resistance against photobleaching, and simultaneous excitation of multiple fluorescence colors. Recent advances have led to the development of multifunctional nanoparticle probes that are very bright and stable under complex in vivo conditions. A new structural design involves encapsulating luminescent QDs with amphiphilic block copolymers and linking the polymer coating to tumor-targeting ligands and drug delivery functionalities. Polymer-encapsulated QDs are essentially nontoxic to cells and animals, but their long-term in vivo toxicity and degradation need more careful study. Bioconjugated QDs have raised new possibilities for ultrasensitive and multiplexed imaging of molecular targets in living cells, animal models and possibly in humans.
Gao
Xiaohu
X
Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, 1639 Pierce Drive, Suite 2001, Atlanta, GA 30322, USA.
Yang
Lily
L
Petros
John A
JA
Marshall
Fray F
FF
Simons
Jonathan W
JW
Nie
Shuming
S
D000818:Animals; D002452:Cell Count / Q000379:methods*; D002468:Cell Physiological Phenomena; D002477:Cells; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008856:Microscopy, Fluorescence / Q000379:methods*; D008967:Molecular Biology / Q000379:methods; D015336:Molecular Probe Techniques; D045663:Quantum Dots; D013057:Spectrum Analysis / Q000379:methods*