UP scientists make thermoresponsive polymers for biomedical use

MANILA, PHILIPPINES – University of the Philippines (UP) scientists have created thermoresponsive polymers that promise astounding biomedical applications.

Thermoresponsive polymers are molecules that undergo significant changes in response to temperature. Researchers Mark Ward and Theoni Georgiou wrote in their 2011 study that this material helps with drug delivery, gene transfer, and other biomedical purposes. 

READ: Smart Citi, other firms launch Philippine Stablecoin

For example, poly(N-isopropyl acrylamide) keeps drugs intact as it passes through the stomach. Then, it breaks down once it reaches the intestines to release the medicines. 

Experts have various methods for creating thermoresponsive polymers. However, it is difficult to create the optimal chain lengths, leading to reduced effectiveness.

In response, UP Diliman College of Science (UPD-CS) chemists have identified a simple, inexpensive, and environmentally friendly method of creating thermoresponsive polymers. Leading the research are:

• UPD-CS Institute of Chemistry researcher Ludhovik Luiz Madrid 
• UPD-CS Institute of Chemistry researcher Dr. Susan Arco
• Natural Sciences Research Institute researcher Lynon Perez

They used monomers di(ethylene glycol) methyl ether methacrylate (DEGMEMA) and methyl methacrylate (MMA) in a hexyl pyridinium ionic liquid, N-hexyl pyridinium hexafluorophosphate ([HPY][PF₆]).

The researchers synthesized linear and hyperbranched structures using ethylene glycol dimethacrylate (EGDMA) as the crosslinking agent for the hyperbranched copolymer. 

Their thermoresponsive polymers were biocompatible, meaning they could interact with living tissues without causing adverse effects.

“RAFT polymerization helps control the growth of polymer chains by mitigating the formation of chains that can no longer grow (a.k.a. ‘dead’ polymers),” Madrid explained, “thereby creating a narrower molecular weight distribution, which can allow more tailored polymer designs or properties.”

Their study opens new polymer research possibilities. “The results open up the potential for using other hexylpyridinium ionic liquids to create dual-responsive polymers, which are valuable for biomedical applications such as drug delivery,” he concluded.