I worked on designing something along these lines in a bioengineering design class I took for fun freshman year.

The idea (for us) was motivated by the work that Ram Sasisekharan had done in his lab along these lines:

http://web.mit.edu/newsoffice/2005/nanocell.html

Some food for thought: There's a lot of control that wrapping stuff in nanomaterials could offer (targeted delivery/delayed delivery)- but the issues that you run into include material compatibility (the biggest problem) and difficulty getting to especially tricky organs like the lungs.