Nanocomposites for bone tissue engineering

J. P. CATTALINI; L. HARO DURAND; A. R. BOCCACCINI; S. LUCANGIOLI; V MOURIÑO

Riberao Preto

Congreso; 9th International Congress of Pharmaceutical Sciences; 2013

Pharmaceutical Sciences Association

A suitable biomaterial for scaffolds for bone tissue engineering (BTE) should have nanofeatures that resemble the extracellular bone matrix. In addition, metallic ions as therapeutic agents have been incorporated into scaffolds and dissolution products from biomaterials produce different intra- and extracellular responses that play a role in bone formation. Particularly, Ca2+ is involved in the formation and mineralization of bone and it is present in most of biomaterials for BTE. The aim of this work was to develop a new nanocomposite biomaterial made of alginate with bioactive glass nanoparticles (nBG) and Ca2+ incorporated for BTE applications. Films were characterized by scanning electron microscopy (SEM), infrared (IR) spectroscopy, tensile strength measurements, bioactivity assays, and degradation and swelling studies. The release of Ca2+ was quantified by a new capillary electrophoresis method recently developed. Dissolution products from the films were used for in vitro cellular studies (human umbilical vein endothelial cells -HUVECs- were used). Then, scaffolds with the same composition as that of films were prepared by freeze-drying and characterized by SEM. The surface of films studied by SEM was homogeneous. Tensile strength significantly increased after the incorporation of nBG into the matrix. After submerging the films in simulated body fluid, the growth of hydroxyapatite (HA) crystals was observed on the surface of films by SEM and confirmed by X-ray diffraction measurements. The degradation study indicated a significant weight loss, whereas the swelling study indicated a weight gain of 100%. A total of 30 µg/mL of Ca2+ were released in a controlled manner. The In vitro cellular study showed that dissolution products after 24 h induce the proliferation of HUVECs. The characterization of scaffolds showed uniform and well distributed pores. Based on mechanical properties, biodegradability, bioactivity and results of the in vitro cell study from the films, this novel biomaterial was applied on the preparation of multifunctional 3D scaffolds for BTE. Future efforts will be focused on the characterization of the scaffolds and the study of the release of different dissolution products that may play a role in the proliferation of bone cells and angiogenesis. Acknowledgements: This work was supported by ANPCyT (grant PICT 0138) and University of Buenos Aires (grant UBACYT 20020100100807).