Content-dependent biomineralization activity and mechanical properties based on polydimethylsiloxane-bioactive glass-poly(caprolactone) hybrids monoliths for bone tissue regeneration

In this study, polydimethylsiloxane-bioactive glass-poly(caprolactone) (PDMS-BG-PCL) hybrid monoliths with various PDMS-BG contents were successfully fabricated via a typical sol-gel route. As a reinforcement, the PDMS-BG was used to improve the biomineralization activity, mechanical properties and osteoblasts biocompatibility of PCL polymer. The incorporation of PCL significantly decreased the formation time and increased the toughness of crack-free PDMS-BG-PCL hybrid monoliths. The mechanical properties of PDMS-BG-PCL hybrid monoliths were significantly affected by the content of PDMS-BG and PDMS-BG-PCL (30 wt%) showed a much higher elastic modulus (328.87 +/- 18.82 MPa). The hydrophilicity of PDMS-BG-PCL hybrids was also increased as the PDMS-BG increased. Additionally, the biomineralization activity of PDMS-BG-PCL hybrid monoliths could be tailored by the PDMS-BG content. All PDMS-BG-PCL hybrids could induce fast deposition of a crystalline apatite layer on their surface in SBF for 7 days. The in vitro cellular studies also showed that PDMS-BG-PCL hybrids can enhance osteoblasts attachment and cell viability compared with PCL. The crack-free monolith structure, biomimetic hybrid composition and high apatite-forming bioactivity make PDMS-BG-PCL hybrid a promising candidate as scaffolds and implants for drug delivery and bone regeneration applications.