Gillies engineers polymers to improve and contain pharmaceuticals

Dr. Elizabeth Gillies

Western Engineering News | March 31, 2015

By Jason Teakle

Elizabeth Gillies is taking advantage of the properties of nanoparticles by working to use unique degradable polymers to encapsulate pharmaceutical drugs, to target intended treatment purposes more efficiently and reduce side effects.

Gillies, a cross-appointed associate professor with the Department of Chemical and Biochemical Engineering and the Department of Chemistry in the Faculty of Science, and Tier II Canada Research Chair in Biomaterials Synthesis, said the research project – which is funded by an NSERC Discovery Grant and her Canada Research Chair – remains in its early stages.

“Right now, we are developing new end-capped biodegradable polymers and using them to prepare nanoparticles that can encapsulate drugs. We can engineer the end cap – or a molecule on the end of the polymer that stabilizes it – to be responsive to different conditions, for example mildly acidic pH, which are found in cancerous tumours,” Gillies explained. “The nanoparticle would circulate around the body in a stable state and once it encounters a tumour, it would be triggered to degrade and result in the release of chemotherapy drugs.”

Using nanoparticles to encapsulate drugs improves their solubility in water, increases the amount of time that drugs can remain in the body and helps pinpoint specific tissues in need of treatment, such as tumours.

“Nanoparticles are well-known to enhance the circulation of drug molecules,” Gillies explained. “They can also be used to target drugs to specific tissues, reducing their side effects.

“But, ultimately we need to release the drug, which is what our polymer is designed to do. We envision using these polymers as a stimuli-responsive coating or using them to form the nanoparticle itself.”

A group of four graduate students, two undergraduate students and a postdoctoral fellow – all in Chemistry or Chemical and Biochemical Engineering – are assisting Gillies with this particular research project.

Careful molecular engineering conducted by Gillies and her research team will allow many potential applications of the degradable polymers under development in her group.

“We can take a single polymer backbone and trigger it to depolymerize under different conditions, just by changing the end cap,” Gillies explained. “When the end cap is removed, it initiates a cascade of reactions that lead to the unzipping or degradation to something that is assimilated into its environment.

“To remove the end cap, we can make it responsive to UV light, specific enzymes, mildly-acidic pH or changes in oxidation or reduction potential.”

The research is expected to attract interest from pharmaceutical, chemical and biotech companies, once the potential applications are better investigated.

“This is an ongoing project,” Gillies said. “We hope to have some proof of concept application studies within three to five years.”

Gillies came to Western in July 2006 after finishing her BSc at Queen’s University, PhD at the University of California, Berkeley, and serving as the Marie Curie Postdoctoral Fellow at the University of Bordeaux, France. Learn more about her research areas here.