Characterization and biocompatibility of nanohybrid scaffold prepared via in situ crystallization of hydroxyapatite in chitosan matrix

Hydroxyapatite (HAP) precursor solution was first mixed with an acetic acid chitosan (CS) solution. The mixture was then lyophilized to form the original scaffold, which stored the HAP precursors. The nano HAP crystallized homogeneously from the CS matrix during the alkaline treatment to form a nanohybrid scaffold. Scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) were used to investigate the fabrication process of the nanohybrid scaffold. XRD results showed that the in situ deposited mineral (HAP) in the scaffold has phase structure similar to natural bone. FTIR and XPS results indicated that CS's hydroxyl group, amino and amide regulated the nano HAP crystallization process, which resulted in the nano homogeneous distribution of nano HAP and provided nano topographical features for the nanohybrid scaffold. MTT testing and SEM images of human bone mesenchymal stem cells (hBMSCs) cultures revealed the attachment and growth of hBMSCs in the biocomposite scaffold. Cell morphology and viability data showed that the nanohybrid composite scaffold is suitable for use in bioapplications.