“…autoclaving, gamma-irradiation, and ethylene oxide) is sorely needed, due to the limitations of these methods and the development of novel polymeric biomaterials which are usually sensitive to these methods (Matthews et al, 2001, Premnath et al, 1996. Steam sterilization damages or destroys heat-sensitive and hydrolytically labile materials (Dempsey and Thirucote, 1989); γ-irradiation may cause changes in shear and tensile strength, elastic modulus, and transparency of polymers (Dillow et al, 1999); and ethylene oxide has significant effect on molecular weight of some biodegradable polymers (Verheyen et al, 1992). Since CO 2 has a relatively low "critical temperature", it is of particular interest as a low temperature sterilization medium.…”