Comparative analysis of irradiation technologies on high-density polyethylene (HDPE) for biopharmaceutical applications

The impacts of e-beam and X-ray irradiation on medical-grade high-density polyethylene (HDPE) are compared with that of gamma irradiation to evaluate their potential effects on pharmaceutical applications. An extensive suite of analytical techniques was employed to evaluate the chemical and physical transformations of irradiated HDPE. Key findings indicated that irradiation did not significantly alter the mechanical properties, as tensile strength and elongation at break remained stable across all irradiation types and doses. Thermal analysis via Differential Scanning Calorimetry (DSC) revealed a slight decrease in melting temperature at higher doses, with an equivalent melting temperature peak observed for all three irradiation technologies. Electron Spin Resonance (ESR) detected alkyl and allyl radicals, which decreased over time, showing no significant differences attributable to irradiation type or dose. Colorimetric analysis indicated yellowing in the samples, linked to specific additives. The quantification of methionine oxidized byproducts by High-Performance Liquid Chromatography (HPLC) demonstrated that the oxidation potential was equivalent for the three irradiation technologies for HDPE. The study concluded that there was a lack of significant impact of irradiation technologies on several physical, chemical and mechanical properties of HDPE.