Multifunctional inorganic/organic nanocomposite microspheres - reinventing eggs for bone repair applications

This study reports for first time the development of bone-regenerative nanocomposite microspheres re-engineered from chicken eggs. We deployed a novel hybrid crosslinking technique combining chemical and thermal crosslinking to produce highly cross-linked microspheres consisting of organic egg white matrix and bioactive inorganic egg shell nanofillers. The nanocomposite microspheres exhibit enhanced mechanical properties and prolonged degradation profile. Ca2+ released from the microspheres are found to accelerate the biomineralization process, facilitate the stem cell differentiation, and promote the osteogenesis process. In addition, antibiotic drug levofloxacin has been loaded onto the proposed microspheres and the dual function of the microspheres in bacterial infection control and bone regeneration has been successfully demonstrated in animal models. Results show that our nanocomposite microspheres can serve as a promising multifunctional platform for bone repair applications.