SYNTHESIS AND CHARACTERIZATION OF COMPOSITES BASED ON HYDROXYAPATITE NANOPARTICLES AND CHITOSAN EXTRACTED FROM SHELLS OF THE FRESHWATER CRAB Potamon algeriense

Nanocrystalline hydroxyapatite (n-HAp), which has low crystallinity, has attracted great attention due to its similarity to the inorganic part of human bone. Therefore, many studies have focused on creating new formulations combining n-HAp with some biopolymers, such as chitosan, in order to imitate biological bone tissue. The importance of chitosan and its derivatives in biomedical applications has grown significantly in the last three decades due to its biodegradability and renewable source. Besides, chitosan and its derivatives present excellent biocompatibility and biofunctionality, which make them promising materials in bone tissue engineering. In the present study, the chitosan was, first, extracted from the shell of the freshwater crab species Potamon algeriense following demineralization, deproteinization, decolouration (raw chitin) and deacetylation (chitosan) steps. Then, a novel composite based on n-HAp and extracted chitosan (CTS) with varying chitosan contents, from 5% to 20% (w/w), was synthesized and characterized for potential application in tissue regeneration. The obtained composites were characterized using X-ray diffraction, Fourier transform infrared spectroscopy and thermogravimetric analysis. The precipitated n-HAp/CTS nanocomposites similar to natural bone are promising composites for bone tissue engineering applications.