Calcium Phosphate Mineralization on Calcium Carbonate Particle Incorporated Silk-Fibroin Composites

In this study, three anhydrous forms of calcium carbonate, namely vaterite, aragonite and calcite, with distinct morphologies were incorporated inside silk-fibroin to fabricate composite scaffolds for tissue engineering applications. To assess calcium phosphate mineralization, composite scaffolds were treated with simulated body fluid up to one month. It was observed that composite scaffolds having different calcium carbonate polymorphs expressed different mineralization. Incorporating 25 wt. % of vaterite polymorph, which was the least stable form of calcium carbonate under aqueous conditions, induced the highest calcium phosphate mineralization in silk-fibroin while calcium carbonate-free silk-fibroin scaffolds expressed no calcium phosphate deposition. Results highlighted the importance of calcium carbonate particles in enhancing the bioactivity of silk-fibroin based composite scaffold