Silicon carbide quantum dots for bioimaging

Luminescent nanocrystals or quantum dots (QDs) have great potential for bioanalysis as well as optoelectronics. Here we report an effective and inexpensive fabrication method of silicon carbide quantum dots (SiC QDs), with diameter below 8 nm, based on electroless wet chemical etching. Our samples show strong violet-blue emission in the 410-450 nm region depending on the solvents used and particle size. The cytotoxic properties of the SiC QDs based on alamarBlue (TM) assay cells were studied. The presence of the QDs dots does not affect cell growth in a wide concentration range. Two-photon excitation showed significant response from SiC nanocrystals that were injected into hippocampal CA1 pyramidal cells.