Researchers use microneedles to deliver quantum dots

For a couple of decades now, nanoscale crystals called quantum dots have held promise in fields as varied as semiconductors and medical diagnosis. But for in vivo applications, as it is with most things nanoscale, the promise is deferred until an efficient, accurate way of delivering them is invented. And now researchers from North Carolina State University think they've found a way. To deliver a nanoscale dot, they need a tiny, hollow microneedle.

Roger Narayan, one of the lead researchers at NC State's College of Engineering and the University of North Carolina at Chapel Hill, says his group developed a laser-based rapid prototyping approach to creating microneedles of varying lengths and shapes, potentially allowing doctors to customize them for specific treatments.

"The motivation for the study was to see whether we could use microneedles to deliver quantum dots into the skin," Narayan says in a news release. "Our findings are significant, in part, because this technology will potentially enable researchers to deliver quantum dots, suspended in solution, to deeper layers of skin. That could be useful for the diagnosis and treatment of skin cancers, among other conditions."

For now, they're content to use pig skin before they try this on a human. Researchers used a water-based solution containing quantum dots and were able to capture images of the way quantum dots enter the skin, verifying the effectiveness of microneedles in delivery quantum dots. The results, says Narayan, will also be useful in developing other small-scale medical device applications.

A paper describing the study, "Multiphoton microscopy of transdermal quantum dot delivery using two photon polymerization-fabricated polymer microneedles," will be published in the September issue of Faraday Discussions.

- see the NC State release
- read the Technology Review piece