A family of biodegradable polymers called polyketals and their derivatives may improve treatment for such inflammatory illnesses as acute lung injury, acute liver failure and inflammatory bowel disease by delivering drugs, proteins and snips of ribonucleic acid to disease locations in the body.
“The polyketal microparticles we developed are simply a vehicle to get the drugs inside the body to the diseased area as quickly as possible,” said Niren Murthy, assistant professor in the Coulter Department of Biomedical Engineering at Georgia Tech and Emory University. “The major advantage to using these polyketals to deliver drugs is that they degrade into biocompatible compounds that don’t accumulate in a patient’s tissue or cause additional inflammation.”
The new polymer has the advantage of stability in both acids and bases. It degrades only in the presence of reactive oxygen species, which are present in and around inflamed tissue. Cell culture experiments have demonstrated that the microparticles degraded more rapidly in cells that overproduced superoxide, a reactive oxygen species.
“We think these microparticles are going to be fantastic for oral drug delivery because they can survive the stomach conditions before they release their contents in the intestines,” noted Murthy.
Murthy’s group is also examining the use of polyketals to treat acute liver failure – a condition when the liver stops functioning because macrophages in the liver create reactive oxygen species. One treatment is the delivery of superoxide dismutase, an enzyme that detoxifies superoxide. Incorporating the enzyme inside a polyketal – poly(cyclohexane-1,4-diyl acetone dimethylene ketal) – allows the enzyme to be released very quickly in an acidic environment.
Release date: August 20, 2008
Source: Georgia Institute of Technology Research News
Filed Under: Drug Discovery