Chemists have fashioned tiny dots of carbon that glow in response to light. The nanoparticles may find uses in biological imaging as alternatives to quantum dots, fluorescent spheres of semiconductors.
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Although scientists envision quantum dots in a variety of applications, the toxicity of their starting materials could limit their use, notes Ya-Ping Sun of Clemson (S.C.) University. The dots, from 2 to 10 nanometers (nm) across, are typically made of cadmium selenide or lead sulfide.