Liquid and Supercritical Carbon Dioxide-Assisted Implantation of Ketoprofen into Biodegradable Sutures

In this study we explored the use of liquid and supercritical carbon dioxide for the creation of a sustained release drug delivery device. An anti-inflammatory (ketoprofen) was dissolved into carbon dioxide at various temperatures (25-55 degrees C) and pressures (65-300 bar) and then exposed to biodegradable braided sutures made of poly(lactide-co-glycolide) copolymers. The effect of temperature, pressure (and hence density), and exposure time were explored on the ability of the sutures to absorb ketoprofen. The diffusion of the drug into the suture was modeled, and diffusion coefficients were calculated. The amount of ketoprofen loaded into the suture increased with pressure and density and decreased with temperature; however, increasing temperature tended to speed up the absorption process.