Antibiotic Functionalization of hydroxyapatite Bone Substitute with Zn and Ag,

S. P. BOEYKENS; J. A. GÓMEZ KRAWIECKY; N. PIOL; A. B. SARALEGUI; A. OZOLS,

Buenos Aires

Congreso; 2nd Latin Amirican Conference on Sustainable Development of Energy, Water and Environment Systems; 2020

Facultad de Ingeniería - UBA

The bovine bone, an abundant and low value waste of the meat industry, is subjected to physical-chemical processes which are compatible with environment care in order to transform it in higher value products destined to bone substitutes employed in regenerative medicine. Its inorganic phase is hydroxyapatite (HA), Ca5(PO4)3(OH), and it is employed as scaffold in bone tissue reconstruction and regeneration. One of its most relevant properties, which concerns to medical application is its ability to absorb aqueous solutions and blood. However, the involved mechanisms are not clearly determined, and even less, how to improve their efficiency. This work intends to increase the water absorption capacity to improve the HA integration to the autologous bone, accelerate the process of absorption of blood tissue and physiological solutions. This purpose involved the modification of HA surfaces by means of different thermal and chemical treatments, leading to their functional modification. It was determined that the optimum bone pyrolysis temperature was 800 °C for improving absorption. The water absorption was analysed by gravimetric methods and correlated with wettability, measuring contact angle on pressed HA powder in form of tablets. This exhibited a water absorption index up to 20% (in weight) after 24 hours of immersion. Moreover, treatments with phosphoric acid improved wettability significantly. In addition, the effect of polysaccharides allowed the production of composite beads based on calcium alginate-HA improving absorption index up to 70% (in weight). The tested treatments have shown the feasibility of producing bone substitutes with improved water absorption when comparing it with no modified HA.