Alginate/Bioactive Glass Beads: Synthesis, Morphological and Compositional Changes Caused by SBF Immersion Method

Composites of biodegradable polymers/bioactive glasses (BG) are of particular interest in bone repair, where ceramic phase can improve osteogenic features. This work reports the development of organic–inorganic beads based on alginate prepared by incorporating at polymer suspension different contents (25, 50 and 75 wt% with respect to alginate) of BG present at precursor solution, whose system (SiO₂–CaO–P₂O₅) was obtained by hydrolysis of both tetraethoxysilane (TEOS) and triethylphosphate (TEP) alkoxides, molar ratio TEOS:TEP of 1:0.1317, and which calcium source came from the same cold CaCl₂ solution used to gelling the hybrids. Beads were synthesized by extruding mixtures, drop by drop, in CaCl₂ solution. Were also investigated the behavior resulting upon soaking of hybrids into SBF. Samples were characterized by SEM, ATR-FTIR, TGA and XRD analysis. Results indicated decrease in spheres size with increase of glass and presence even pos-immersion, of Si, Ca and P associated to BG phase.

Keywords:
Alginate; bioactive glass; microspheres; composite; biomaterials