COMPOSITES SCAFFOLDS FROM NANO-HYDROXYAPATITE/POLYELECTROLYTE COMPLEX FOR BONE TISSUE ENGINEERING

MEDINA, L.F.; BELLUZO, M. S.; CORTIZO, A.M.; CORTIZO, M.S.

Foz do Iguazu

Congreso; 9° Congresso Latino-Americano de Orgãos Artificiais e Biomateriais; 2016

In recent years, there has been an increasing interest in the design of biomaterials for cartilage and bone tissue engineering. To regenerate tissue it is necessary a scaffold that works as a temporary matrix for cell proliferation with subsequent ingrowths until the tissue is totally regenerated [1]. In addition, biomaterials designed for biomedical applications must meet more stringent requirements than those used for other applications, due to the demand of non-toxicity, degradability and biocompatibility.Recently, we used an ultrasound metodology to prepare a compatibilized blend of polyelectrolyte complexes (PEC) based on carboxymethyl cellulose (CMC) and chitosan (CHI) [2]. The scaffolds properties and non-cytotoxicity indicated that these materials could be useful in cartilage tissue regeneration.In order to improve the properties of the scaffolds, in this work we obtained polymerics blends of CMC-CHI- nano Hap (nano hidroxiapatite). Hap is a natural component of the bone and highly biocompatible, and has shown to improve the cell adhesion and the enhancement of the osteogenic and mechanical properties in polymeric blends [3]The biocomposite was prepared from 1% w/v CHI solutions in 0.25% w/v acetic acid and 1% w/v CMC; the nano HA was obtained by a procedure developed in our laboratory, and was added at different percentages from 0 to 20%. The biocomposite samples were obtained by dropping CMC into a solution of CHI-HA under constant stirring and in the presence of ultrasound. Finally, the composites were freeze-drying until constant weight was achieved.The morphology (by scanning electron microscopy), polyelectrolyte interactions (by FTIR), swelling and mechanical properties of these composites were analyzed. In addition, we evaluate the in vitro cytotoxicity of the scaffolds using macrophage cells in culture. The SEM results show a three-dimensional porous structure of the CHI-CMC-nanoHa scaffolds with a mean pore size suitable for cell proliferation. FTIR-ATR analysis showed specific interactions between the components in the biocomposite and the presence of the HA in the structure. The swelling studies and mechanical test indicate that the composite displays hydrogel properties with enhanced mechanical properties. Finally, no cytotoxicity was found for any scaffold.These results let us concluded that CMC-CHI-nanoHap composite is a promising candidate for bone regeneration.