Tunable physicochemical and biocompatibility properties of PCL/HAp/BN composite films through γ-irradiation

This study explains the effects of γ-irradiation on the physical and biological properties of polycaprolactone/hydroxyapatite/boron nitride (PCL/HAp/BN) composite films with fluences of 25, 50, 75, and 100 kGy. SEM micrographs revealed a distinct microporous surface morphology in the composite film treated at 75 kGy, indicating significant structural modifications induced at this irradiation dose. AFM result showed that surface roughness was attained twice that of the pristine. Crystallinity and crystallite size were found to decrease with irradiation, and the predominant (110) peak of PHB was slightly shifted from 21.5 to 21.7° at 50 kGy. Water contact angle (WCA) measurements demonstrated increased hydrophilicity, with values rising from 83 to 89° up to 50 kGy. The composite film irradiated at 75 kGy exhibited the lowest hemolytic activity, higlighting its superior hemocompatibility than that of pristine and other irradiated samples. Cell viability assays revealed that fibroblast proliferation reached its maximum at 75 kGy, outperforming both the pristine and other irradiated composite films. These results highlight the ability of γ-irradiation to tune key properties of PHB composite films, including crystallinity, surface roughness, hydrophobicity, hemocompatiblity, and cell proliferation. By enhancing the morphological, structural, and biological performance, γ-irradiated PHB composites show great promise for tissue engineering applications.