For more than a decade, biomedical researchers have been looking for better ways to deliver cancer-killing medication directly to tumors. Tiny capsules called nanoparticles can transport chemotherapy medicine through the bloodstream, but the challenge is coming up with a delivery vehicle that is sturdy enough to survive the bumpy ride and also lithe enough to squeeze through a tumor’s dense extracellular space — a matrix stuffed with sugars called hyaluronic acid.

In the journal Nano Letters, senior author Hao Cheng, an assistant professor with an appointment in the College of Engineering and affiliation with the School of Biomedical Engineering, Science and Health Systems, reported that his team, which includes Wilbur Bowne, a professor in the College of Medicine, had developed a method that involves the decoration of nanovehicles with enzymes known to break down the acid. There is also an extra layer of polyethylene glycol to partially cover the enzymes ensuring that particles have sufficient time to enter into tumors. The method is four times more effective at sending nanoparticles into a solid tumor than one of the best strategies in use, the group found.

The team tested their nanoparticle against competitors that lacked the additional layer of polyethylene glycol and ones that didn’t have the enzymes. Their nanoparticle performed better in both penetrating tumors and in accumulating in the cancerous cells to get to work.