A novel bioceramic scaffold integrating silk fibroin in calcium polyphosphate for bone tissue-engineering

The advantages of bioceramics, such as biocompatibility and osteoconduction, have been widely used for bone repair and substitute as bone tissue-engineering materials. Bioceramic scaffolds however still need improvement to meet the requirements for complex bone repair. The aim of this study was to develop novel bioscaffolds for bone regeneration, based on the combination of silk fibroin (SF) and calcium polyphosphate (CPP) composite scaffolds. In this study, Bombyx mori silk fibroin (BMSF) and Antheraea pernyi silk fibroin (APSF) were prepared, and applied into CPP scaffolds with glutaraldehyde crosslinking to form the BMSF/CPP and APSF/CPP bioceramics. These scaffolds were then undergone the strength tests, morphology evaluation, and assessments for biodegradation and biocompatibility. Our results showed that the CPP-type bioceramics presented a higher compressive strength and enhanced degradation after the silk fibroin was doped into a CPP structure. Moreover, the BMSF/CPP and APSF/CPP-type scaffolds exhibited lower cellular toxicity than those of the CPP and HA types. Considering the improved mechanical characteristics and degradation as well as ready availability, SF/CPP may be considered a suitable bioceramic for bone tissue-engineering.