*Article* **Highly Bioactive Elastomeric Hybrid Nanoceramics for Guiding Bone Tissue Regeneration**

**Jing Chen 1,2,\*, Wenxiu Que 2,\*, Bo Lei <sup>3</sup> and Beibei Li <sup>1</sup>**


**Abstract:** Conventional bioactive ceramic implants possess high osteogenic ability but exhibit poor machinability and brittleness, which limit their wide applications. In this study, we report an elastomeric machinable bioactive nanoceramic-based hybrid membrane that is formed by nanohydroxyapatite-reinforced hybrid matrix (poly(dimethylsilicone)-bioactive glass-poly(caprolactone) (nHA-PBP)) using a modified sol-gel process. The hybrid matrix is composed of elastomeric polydimethylsiloxane and bioactive glass nanogel. The effect of the nHA contents (0, 20, 30, 40 and 50 wt%) on the physicochemical structure and biomineralization activity of PBP hybrid membranes is investigated systematically. The results show that nHA-PBP hybrid membranes containing more than 20 wt% nHA exhibit the highest apatite-forming bioactivity due to the optimized hydroxyapatite crystalline phase. NHA-PBP implants with nHA also show good elastomeric mechanical behavior and foldable mechanical properties. Furthermore, the study of the in vitro cellular biocompatibility suggests that the nHA-PBP hybrid monoliths can enhance osteoblast (MC3T3-E1) attachment and proliferation. The biomimetic hybrid composition, crack-free monolith structure, and high biological activity of apatite formation make the nHA-PBP hybrid membrane a prospective candidate in the application of bone tissue regeneration.

**Keywords:** bioactive materials; bioactive ceramic; bioactive glass; nanohydroxyapatite; sol-gel process
