Graphene works in drug delivery, but will it leave the body?

Graphene, that new rock star of the nano world, whose inventors won the Nobel Prize in physics this year, is being investigated as a possible drug delivery device. However, there are a few steps nanotech-enabled drug delivery needs to follow before it truly arrives, and the last part is among the most important. It has to harmlessly go away after it's done its jobs and dropped off its payload of therapeutics.

Yongsheng Chen from Nankai University, China, and colleagues have developed a delivery system using functionalised graphene oxide as the drug carrier. Graphene oxide has a very high surface area, which makes it able to transport a large amount of the drug. Like other drug-delivery materials, the graphene is "programmed" to release its therapeutics when it detects the pH level typical of cancer tumors. Just to be sure the graphene finds the right spot, Chen also threw in a couple of other ingredients: superparamagnetic Fe3O4 nanoparticles, allowing an external magnetic field to guide the graphene, and folic acid to target the high numbers of folate receptors on many tumors.

So, that takes care of the target-and-release part of it. Now, how to make the stuff harmlessly go away? Chen tells Chemical Science, that needs a little more work.

"Nanomaterial-based targeting drug delivery systems are still at an early stage for commercial applications," Chen says to Chemical Science. "Some reports suggest that modified graphene can be excreted safely from the body, but the digestion or downgrading of nano-delivery vehicles needs more research. This is the focus of our future studies."

- read the article in Chemical Science