Quantum dot conjugated hydroxylapatite nanoparticles for in vivo imaging.

Hydroxylapatite (HA) nanoparticles were conjugated with quantum dots (QDs) for in vivo imaging. The surface structures of HA nanoparticles with conjugated quantum dots (HA-QD) were studied by transmission electron microscopy (TEM) and laser fluorescent spectroscopy. The TEM data showed that the quantum dots were well conjugated on the HA nanoparticle surfaces. The laser fluorescent spectroscopy results indicated that the HA-QD exhibited promising luminescent emission in vitro. The initial in vivo experiments revealed clear images of HA-QD from the hypodermic injected area at the emission of 600 nm. Furthermore, the optimized in vivo images of HA-QD with near-infrared emission at 800 nm were visualized after intravenous injection. These luminescent HA-QD nanoparticles may find important applications as biodegradable substrates for biomarkers and in drug delivery.