Researchers at Harvard-affiliated McLean Hospital have shown a new category of "green" nanoparticles comprised of a non-toxic, protein-based nanotechnology that can non-invasively cross the blood brain barrier and is capable of transporting various types of drugs.

In an article published May 1, 2012 online in PLoS ONE, Gordana Vitaliano, MD, director of the Brain Imaging NaNoTechnology Group at the McLean Hospital Imaging Center, reported that clathrin protein, a ubiquitous protein found in human, animal, plant, bacteria and fungi cells, can been modified for use as a nanoparticle for in-vivo studies. "Clathrin has never been modified for use in vivo and offers many new and interesting possibilities for delivering drugs and medical imaging agents into the brain", said Vitaliano.

Read the full press release here...

Also, a related application of dendrimers here...