Monodisperse photoluminescent and highly biocompatible bioactive glass nanoparticles for controlled drug delivery and cell imaging

Abstract

Bioactive glass nanoparticles (BGNs) have attracted widespread interest recently and been explored as the promising drug or gene delivery carriers due to their high biocompatibility and tissue repair ability. However, the synthesis of monodispersed photoluminescent BGNs and their corresponding biomedical applications are still not explored. Here, for the first time, we report monodispersed Eu-doped photoluminescent bioactive glass nanoparticles (BGN-Eu) and demonstrate their biomedical applications for drug delivery and cell imaging. By a long chain amine assisted sol–gel method, we synthesized the monodispersed BGN-Eu with combined dual functions of bioactivity and luminescence properties, and further investigated their physicochemical structure, biomineralization activity and biomedical applications. As-prepared BGN-Eu possessed the spherical morphology, relatively homogeneous particle size (200 ∼ 400 nm) and representative red fluorescence emission characteristic of Eu³⁺ at 616 nm. In simulated body fluids (SBFs), the BGN-Eu demonstrated excellent bioactivity by inducing biological apatite mineralization. BGN-Eu also presented controlled drug (theophylline) loading ability and release behavior. The osteoblast (MC3T3) growth was significantly enhanced when incubated with different dosages of BGN-Eu, suggesting the high biocompatibility. In addition, BGN-Eu was successfully used to label the MC3T3 cell by a strong red fluorescence with low background noise. Our results suggest the great potential of BGN-Eu as multifunctional bioactive nanomaterials for cell imaging and bone tissue regeneration applications.