Radiation Grafting of Two PEG Derivatives onto PET: A Comparative Study for Biomedical Applications

This study shows an alternative route for the functionalization of polyethylene(terephthalate) (PET) for biomedical applications using gamma radiation instead of the conventional chemical method. Radiation technique is a versatile and effective strategy to improve the properties of polymers avoiding the use of toxic chemical agents that compromise their biocompatibility. Here, PET was modified by grafting poly(ethylene glycol) methyl ether methacrylate (PEGMEMA) and di(ethylene glycol) methyl ether methacrylate (DEGMEMA) using simultaneous and oxidative pre‐irradiation methods. Results indicate that both PEG‐methacrylate derivatives are successfully grafted (1‐9%) by oxidative pre‐irradiation, while the simultaneous method yields negligible modification (<0.6%). Characterization by infrared spectroscopy, thermogravimetric analysis, contact angle, and swelling studies reveals similar physicochemical properties between PET‐ g ‐PEGMEMA and PET‐ g ‐DEGMEMA. However, mechanical properties denote that DEGMEMA increases PET stiffness, whereas PEGMEMA preserves the tensile elastic modulus of pristine PET. Similarly, protein adsorption (albumin) and fibroblast adhesion (BJ cells) assays show that both PEG‐methacrylates promote the biological responses compared to pristine PET. Notably, samples with higher grafting densities support fibroblast adhesion and proliferation up to 5 days, attributing to increased hydrophilicity. No substantial difference between PEGMEMA and DEGMEMA grafts is observed regarding cell adhesion. These findings highlight the potential of PET‐ g ‐PEGMEMA and PET‐ g ‐DEGMEMA as promising candidates for biomedical technologies.