Nanoparticles carrying a cancer drug are administered to mice and exposed to UV light, causing them to contract and release the drug into tumors.
Credit: Modified from Proc. Natl. Acad. Sci. US
http://cen.acs.org/articles/91/i45/Improving-Drug-Delivery.html
Nanoparticles are promising cargo ships for targeted drug delivery. But the materials have had limited success treating cancer, because they often can’t penetrate deep into tumors. The nanoparticles are stalled by the extracelluar matrix and compressed blood vessels.
http://cen.acs.org/articles/91/i45/Improving-Drug-Delivery.html