Grafting of phosphonylated polymers onto 3D printed polycaprolactone scaffolds improves osteoblasts proliferation and calcium mineralization in-vitro

Prosthesis implantation or bone grafting are currently used to treat bone defects induced by osteoporosis, bone tumors or fractures. However, these conventional surgical techniques can lead to significant complications, including infection, loosening, and rejection. Consequently, additional surgeries or even amputation of the affected limb may become necessary. In this context, advancing the strategies used for bone repair remains a critical challenge. The present preliminary study outlines a method for developing biodegradable and bioactive PCL implants with improved osteoblast biological response for bone regeneration., vinylbenzylphosphonic acid (VBP) monomer was grafted and polymerized onto the 3D printed cylindrical polycaprolactone (PCL) implants using a two-step UV irradiation process. To refine and optimize the grafting conditions, key parameters such as ozonation time, UV irradiation duration, and reaction medium were adjusted. The success of the grafting process was assessed using various characterization techniques, including colorimetry, contact angle measurements, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Attenuated Total Reflection-Fourrier Transform Infrared Spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), and size-exclusion chromatography (SEC). Furthermore, a study of the cellular response focusing on viability, morphology, and mineralization was conducted using mouse preosteoblasts (MC3T3-E1 cell line). The results demonstrated the beneficial effects of grafting a bioactive polymer containing a phosphonate group onto implant surfaces.