Alternative methods of sterilization on films of polymers: Poly(-L-lactic acid) (PLLA), Poly(L-lactic acid-co-glycolic acid) (PLGA) and Poly(-LD-lactic acid) (PLDLA), for bioresorbable vascular scaffolds models

Abstract

Biodegradable polymers have been the subject of study for more than three decades because of their unique characteristics such as: biocompatibility and non-immunogenic and non-toxic properties, revealing their great acceptance in living organisms and being used as fastening elements in materials such as prostheses, sutures, drug encapsulation matrices and several important applications. The Poly(-lactic acid) (PLLA and PLDLA) and its glycolic acid copolymer (PLGA), present great biocompatibility. A problem when using polymers in bioengineering is sterilization process, which should enable the inactivation of a wide variety of microorganisms without affecting the properties of the materials of the device sterilized. Most of the processes used have limitations for use in thermo sensitive and chemo sensitive materials. Among the alternatives are ultraviolet radiation (UV) and plasma of hydrogen peroxide. This project tested these two alternatives methods, in films and tubes of these polymers. After the process of sterilization, no changes were found in thermal properties evaluated by differential scanning calorimetric analysis (DSC) and termogravimetric analysis (TGA). The mechanical properties of the PLLA, PLDLA and PLGA materials after the sterilization processes, also presents no changes, by UV and plasma, indicating the stability of samples to these processes.