Synthesis of HAp/chitosan composites via electrospinning: Preliminary results

Human bone is a hydroxyapatite HAp (HCa₅O₁₃P₃) and type I collagen based composite. Nowadays, many methods and techniques have been developed and applied to design advanced materials for bone replacement. A strategy for imitating in a tridimensional way the structure, composition and mechanical properties of a bone is mimicking it at nanometric scale. This can be carried out, by incorporating selective of nanoparticles of apatites into a polymeric matrix by controlling structure and composition of the fibers. In this work we present the preliminary results of HAp/Chitosan composites prepared by the electrospinning technique. HAp/Chitosan fibers were spun from different aqueous solutions, all of them with a pH= 3. The compositional and structural characteristics were obtained by using scanning electron microscopy SEM, energy dispersive spectroscopy EDS, X-ray diffraction XRD, and infrared spectroscopy IRS. EDS and XRD confirmed that the mineral deposits correspond to hydroxyapatite and calcium phosphate monobasic MCP (CaH₄O₈P₂), which are present in the human bones. Comparative studies were made from chitosan and HAp/Chitosan solutions. In this respect IRS analysis showed that the characteristic chitosan stretch band in the 1020-1220 cm^-1 range was attenuated when HAp was added. Additionally, from a precursor solution prepared at pH=3, 1% w/v chitosan, and 1% w/v HAp and spun at 20 V, a Ca/P ratio close to bone composition (Ca/P_bone = 1.67) was obtained.