Clemson University chemists say they have developed a new type of quantum dot that is the first to be made from carbon.

As their metal-based counterparts, the nano-sized carbon dots glow brightly when exposed to light and show promise for a broad range of applications, including improved biological sensors, medical imaging devices and tiny light-emitting diodes the researchers say.

The carbon-based quantum dots show less potential for toxicity and environmental harm and have the potential to be less expensive than metal-based quantum dots, the scientists said. Cheap disposable sensors that can detect hidden explosives and biological warfare agents, such as anthrax, also are among the possibilities envisioned by the researchers.

Carbon is hardly considered to be a semiconductor, so luminescent carbon nanoparticles are very interesting both fundamentally and practically, says study leader Ya-Ping Sun. It represents a new platform for the development of luminescent nanomaterials for a wide range of applications.

The study is described online by the Journal of the American Chemical Society. The paper is to appear in the journal’s June 7 print edition.