Material implants slowly release medicine over period of months
February 2, 2012
Scientists have developed a new material that can slowly release medication over a period of several months. It's hoped that the "superhydrophobic material" may one day lead to implants that would assist in the treatment of chronic pain, and in the prevention of recurring cancer tumors by gradually releasing medication over a period of months. The team of scientists is now planning in vivo experiments to gauge the effectiveness of the material in living organisms.
Superhydrofragilistic ...The superhydrophobic material is, as the name suggests, extremely resistant to water. It's this resistance that means, generally, water touching the material will form beads on the surface, like drops of rain on a laminated surface. Nevertheless, water can penetrate the material, and as it does, air is displaced and released and with it, the medication.
"The idea was to create a 3D material that has polymer fibers throughout and air trapped within," said Professor Mark Grinstaff, who led the research. "If we can slow the penetration of water into the structure, it will slow the release of the drug."
The rate of medication release is dependent upon how firmly the material traps the air inside, which can be varied by altering the chemical and physical properties of the material.
EffectiveBut it seems the research has achieved more than the gradual release of medication. Using anti-cancer drug SN-38, the material proved effective in fighting lung cancer cells over a period of more than 60 days. The tests were carried out in vitro rather than testing within a living organism.
Also on the research team was Dr. Yolanda Colson, a thoracic surgeon and lung cancer specialist at Brigham and Women's Hospital. Does her involvement, weighed with the use of SN-38 in these experiments, suggest that the team's research is specifically targeted at possible cancer treatments?
Grinstaff suggests not. "Many researchers are advancing new drug delivery systems, and several others are designing superhydrophobic materials, but we're combining these disciplines to see if we can open up new doors and enable more effective treatments for a wide range of diseases," he said.
PracticalitiesThe possibilities are intriguing, but the proposed mode of treatment raises a number of questions. It's not clear, for instance, what would happen to the implant when the medication is fully dispensed. Presumably, unless it can somehow be made to safely break down, implants would subsequently require removal - especially if follow-up surgery would be necessary to fit a replacement anyway. We can only speculate, at this point, whether there's a possibility that implants might somehow be "recharged" with air and medication. For the technology to become a reality, questions such as these will one day require answers.
Source: Boston University