Molecular profiling of single cells and tissue specimens with quantum dots.

Quantum dots are tiny light-emitting particles on the nanometer scale. They are emerging as a new class of biological label with properties and applications that are not available with traditional organic dyes and fluorescent proteins. Recent advances, as reported in Science and Nature Biotechnology, have led to quantum dot bioconjugates that are highly luminescent and stable. These bioconjugates raise new possibilities for studying genes, proteins and drug targets in single cells, tissue specimens and even in living animals.