Evaluation of the effect of additive materials on performance of manufactured polycarbonate during the sterilization process by gamma radiation

Abstract Polycarbonate is used in numerous biomedical devices, including blood oxygenators, blood reservoirs, blood filters, dialyzer housings, and bypass circuits. These products are exposed to gamma irradiation during sterilization processes. The goal of this work is to describe the impact of additive materials on the stability of manufactured polycarbonate (M-PC) during sterilization by gamma radiation. The effect of gamma irradiation on the manufactured polycarbonate (M-PC) and its raw material (R-PC) at different radiation doses of 20, 40, 60, and 120 kGy was studied. This evaluation was performed by different analytical tools such as Electron Spin Resonance (ESR), Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), Thermogravimetric analysis (TGA), and Energy Dispersive X-ray (EDX). The formed free radical species and the decay of free radical species with time were evaluated using ESR analysis. The decay of free radical species was evaluated for 7 days after irradiation by gamma rays. The FTIR results indicated that there are new peaks for irradiated R-PC and M-PC samples at 60–120 kGy, and besides that, there is an increase in the intensity of the peaks. Otherwise, TGA data confirmed that the thermal stability of R-PC samples is not affected by gamma doses, while the stability of M-PC slightly decreased with increasing gamma doses. The elemental investigation by EDX confirmed that the R-PC and M-PC have Aluminum (Al) in a trace concentration level.