Researchers find new, better method for studying drug delivery

GAINESVILLE, Fla. — For medical researchers, studying how drugs disperse within the body is a major part of developing effective treatments. Now, a group that includes a University of Florida Health researcher has found a way to dramatically speed up the discovery and understanding of drug-delivery systems.

At the heart of the findings are nanoparticles — microscopic natural or engineered objects between 1 to 100 nanometers in size that have myriad scientific uses, including biomedicine. By encapsulating unique genetic “barcodes” within different nanoparticles, the researchers have found they can study the effects of dozens — and perhaps hundreds — of therapeutics simultaneously within a single animal model.

Until now, researchers could typically test no more than one or a few potential drug treatments at a time in a single animal model, said Eric Wang, Ph.D., a professor in the UF College of Medicine’s department of molecular genetics and microbiology and a faculty member of the Center for NeuroGenetics.

The findings by Wang and co-investigators from the Massachusetts Institute of Technology and the Georgia Institute of Technology appear today in the Proceedings of the National Academy of Sciences.

While researchers can create many thousands of unique nanoparticles with different delivery properties, studying how they perform in animal models has been laborious and expensive. Packaging a drug molecule within a nanoparticle may help get it to the correct tissue, but because researchers could only study small numbers of nanoparticles at a time, Wang said the pace of drug-delivery research has been slow.

“Our new method uses DNA to barcode different nanoparticles so that many can be studied simultaneously in a single animal. We’re now able to study the behavior of many drug delivery vehicles at the same time. This should accelerate our ability to find effective drug-delivery methods,” he said.

The researchers developed a way of distributing 30 chemically distinct nanoparticles to eight tissues simultaneously in a mouse. By employing “deep sequencing,” a technique used to count the nanoparticle-associated barcodes obtained from each tissue, they were able to infer the relative distribution of many nanoparticles simultaneously.

If the technique is adopted widely by other researchers, Wang said it could speed up the pace of discovering nanoparticles with specific and specialized properties. That could help make medications more effective by assuring that they penetrate the relevant cells and tissues more efficiently and with lower toxicity, he added.

Next, Wang said he would like to explore the possibility of working with biomedical engineers who may want to look for ways to apply the technique or use it to study their particle libraries.

“It would be great to identify particles that cross the blood-brain barrier or get into specific cell types in the brain, heart and muscles,” Wang said.

Funding sources for the research included grants from the National Institutes of Health, the Koch Institute Frontier Research Program and the Kathy and Curt Marble Cancer Research Fund.