Enhanced composites based on natural polymers for bone tissue engineering

MEDINA, LARA FERNANDA; BELLUZO MARÍA SOLEDAD; CORTIZO, ANA MARÍA; CORTIZO, MARÍA SUSANA

Los Cocos, Córdoba

Simposio; XII Simposio Argentino de Polímeros (SAP 2017); 2017

IPQA, UNC, CONICET

An ideal material for the bone reconstruction should possess many properties such as ability to fit the defect shape, lack of physical harm to the adjacent tissues, biocompatibility and ability to biomimic the tissue to be restored. The design of an appropriate scaffold includes the type of material, its architecture and porosity, surface chemistry and osteoinductivity as well as mechanical strength. In the present work, we aim to enhance the mechanical properties of polyelectrolyte complexes based on carboxymethyl cellulose (CMC) and chitosan (CHI) [1], obtained by ultrasound methodology, to achieve a material that allow bone regeneration. To achieve this goal, we prepared polymeric blends of CMC-CHI and add nano hydroxyapatite (nHAP), a natural component of the bone that improve cell adhesion and enhancement of osteogenic and mechanical properties in polymeric blends [2]. This nHAP has an average diameter of 24,5 ± 0,2 nm and was obtained by a procedure developed in our laboratory [3], combining mechanical and ultrasonic processing. The biocomposite was prepared as previously published [1], adding the nHAP at different percentages (from 0 to 10%) under ultrasound. Finally, the composites were freeze-drying until constant weight was achieved. The morphology (by scanning electron microscopy), polyelectrolyte interactions (by FT-Infrared spectroscopy), swelling and mechanical properties of these composites were analyzed to seek improvement on the mechanical properties. In addition, we evaluate the in vitro cytotoxicity of the scaffolds using macrophage cells in culture, and evaluated Nitric Oxide production. The results shows an enhancement of the mechanical properties of the scaffold with a mean pore size suitable for cell proliferation, and no cytotoxicity was found for any scaffold. These results let us concluded that CMC-CHI-nanoHap composite is a promising candidate for bone regeneration.REFERENCES[1]M.S. Belluzo, L.F. Medina, A.M. Cortizo and M.S.Cortizo, ?Ultrasonic compatibilization of polyelectrolyte complex based on polysaccharides for biomedical applications?, Ultrasonics Sonochemistry, vol. 30, pp.1?8, 2016.[2]J.M. Fernandez, M.S. Molinuevo, M.S. Cortizo and A.M. Cortizo, ?Development of an osteoconductive PCL?PDIPF?hydroxyapatite composite scaffold for bone tissue engineering?, Journal of Tissue Engineering and Regenerative Medicine, vol 5, no. 6, pp. 126-135, 2011.[3]L.F Medina, M.S Belluzo and M.S. Cortizo, ?Caracterización de nanohidroxiapatita y nanoquitina como refuerzos de scaffolds para medicina regenerativa?, en XVI Encuentro de Superficies y Materiales Nanoestructurados, pp. 191, 2016.TÓPICOS: T01 ? Biopolímeros y polímeros para aplicaciones biomédicas y biotecnológicas