Gold nanoparticles as a therapeutic delivery system into the brain

Treating brain disorders has been a challenge due to the presence of the blood-brain barrier. However, we found that certain gold nanoparticles (< 5 nm) can cross the blood-brain barrier, pointing to potential of being a carrier of a therapeutic cargo. Gold nanoparticles can be coated with ligands which will improve or impede on their transport into the cells. The search for the most effective coating of a gold nanoparticle carrier across the blood-brain barrier lead us to the conclusion that a ligand mixture of PEG-amine and galactose was amongst the most effective nanoparticle coatings in vitro and proved to be the most effective in vivo as well. The results indicate that these nanoparticles have great potential as carriers of therapeutic agents into the brain. Our future work is directed towards finding the best way of coupling therapeutic cargoes onto the nanoparticles so that they are transported across the endothelium and released within the brain.