SUPERCRITICAL FLUID STERILIZATION METHOD

摘要

A method is provided for sterilizing materials, particularly polymers, for drug delivery and implantation, wherein the material is treated with supercritical fluid carbon dioxide at pressures in the range of 2000 to 3000 psi (140 to 210 bar) and temperatures preferably between 30 and 45 DEG C for periods between 20 minutes and six hours, more preferably between 0.5 and 2 hours. Agitation, pressure cycling, and the presence of water were found to enhance the sterilization method, which promotes diffusion of the supercritical fluid carbon dioxide into the cells of the microorganism to thereby alter the pH within the cells, killing them. The magnitude and frequency of the pressure cycling, as well as the process time and temperature, may vary according to the type and form of the material to be sterilized and the type of organisms to be killed.