Biomimetic mineralization on natural and synthetic polymers to prepare hybrid scaffolds for bone tissue engineering

To mimic the mineral component and the microstructure of natural bone, nanohydroxyapatite (nHAP)/polymer (natural and synthetic materials) composite scaffolds with micropore structures and good mechanical performance were prepared via the assistance of sonication and amidation. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) showed the biomimetic homogeneous formation of nHAP in the polymer matrix. Fourier transform infrared spectroscopy (FTIR) indicated that the polymer matrix regulated the crystallization of nHAP. The integration of synthetic/natural polymers benefited nHAP crystallization in the polymer matrix and thus improved the mechanical performance of the chitosan (CS)/collagen (Col)/poly (lactic acid) (PLA)/nHAP scaffolds. The in vitro bioactivity ability was investigated by incubating in a simulated body fluid (SBF). The methyl thiazolyl tetrazolium (MTT) test, the acridine orange/ethidium bromide (AO/EB) and Giemsa staining showed that the scaffolds had good biocompatibility and could maintain the cell growth. Therefore, the CS/Col/PLA/nHAP scaffold is promising for bone tissue engineering applications.