Microstructural characterization and osteogenic efficacy of PVA/PVP blended mineral scaffold for bone tissue engineering

Advances in bone tissue engineering and dental regenerative medicine have made strides in the development of several biomaterials. Optimizing the chemical and physical milieu of scaffold is required to induce osteogenesis for faster bone regeneration. In this study, polymer blend of Polyvinyl Alcohol (PVA) and Polyvinylpyrrolidone (PVP) doped with nHAP-ZnO Np was prepared by a solution casting technique. Structural and physiochemical characterization was performed. In vitro cytotoxicity analysis was performed through tetrazolium-based assay (MTT) assay and the differentiated cells were subjected to alkaline phosphatase assay (ALP) and alizarin red S (ARS) analysis respectively. Scanning Electron microscopic (SEM) analysis showed a rough and uniform matrix arrangement of the PVA-PVP blend. Crystallites properties and functional groups was confirmed by X ray diffractometer (XRD) analysis and Fourier transform infrared spectroscopy (FT-IR) respectively. The optimal water absorption capacity was observed in PVA-PVP-nHAP-ZnO Np scaffold (P3) and also degradation pattern was analysed for PVA-PVP (P1), PVA-PVP-nHAP (P2) and PVA-PVP-nHAP-ZnO Np (P3) scaffolds where P3 scaffold holds high stability compared to P1 and P2 scaffolds. In the thermal stability analysis, PVA-PVP (P1) and PVA-PVP-nHAP-ZnO Np (P3) scaffolds showed an overall stability up to 270 °C. Highly miscible blends of PVA-PVP and 1 wt% nHAP - ZnO Np was observed with semi-crystallinity in Differential Scanning Calorimetry (DSC) analysis. The mechanical property of the PVA-PVP-nHAP-ZnO Np (P3) scaffold has shown an increasing trend in tensile strength analysis. The cytotoxic study of scaffolds showed 84% of cell viability confirming high biocompatibility than compared to plain scaffold. the elevated level of ALP and calcium deposition was observed in loaded scaffold (P3). Thus, PVA-PVP-nHAP-ZnO Np (P3) scaffold supports and induces osteogenesis and can be used as biomaterial in bone regenerative medicine.