In situ silica nanoparticles-reinforced biodegradable poly(citrate-siloxane) hybrid elastomers with multifunctional properties for simultaneous bioimaging and bone tissue regeneration

Abstract Most of current biomedical implants do not possess multifunctional properties including biomimetic elastomeric behavior, enhancing cellular activity, real-time imaging tracking ability. In this study, through an in situ nanoparticles formation process, the silica nanoparticles (SNs) reinforced poly(citrate-siloxane) hybrid elastomers (PCS-SN) with multifunctional properties were developed. SNs with uniform size and spherical morphology were distributed in PCS polymer matrix homogeneously. The structure, elastomeric mechanical properties, biodegradation, photoluminescent ability and osteoblasts biocompatibility of PCS-SN could be well controlled. The addition of SNs significantly enhanced the elastomeric mechanical properties and photoluminescent capacity of PCS. PCS-SN-2.5% exhibited significantly low in vivo inflammatory response and long-term fluorescent imaging performance in vivo. The attachment and proliferation of osteoblasts (MC3T3-E1) was also significantly improved, demonstrating the excellent osteogenic cellular biocompatibility of PCS-SN-2.5%. The novel hybrid structure and multifunctional properties make PCS-SN-2.5% hybrid elastomers promising for simultaneous bone tissue regeneration and bioimaging applications.