Novel selenium and/or copper substituted hydroxyapatite-gelatin-chitosan-eggshell membrane nanocomposite scaffolds for bone tissue engineering applications.

Limitations with the majority of bone therapeutic treatments include low availability, ethical constraints and low biological compatibility. Although a number of choice materials have been exploited successfully, there has always been scope for improvement as well as development of the next-generation of materials. Herein, scaffolds - developed from gelatin, chitosan and eggshell membranes - were crosslinked using tannic acid, and further infused with selenium and/or copper substituted hydroxyapatite nanoparticles to generate a novel nanocomposite substrate. FESEM images of the nanocomposite scaffolds revealed the presence of interconnected pores, mostly spread over the whole surface of the scaffold, alongside XRD and FTIR profiling that detailed the formation of hydroxyapatite as a sole phase. Moreover, physical characterisation of the nanocomposite confirmed that the hydroxyapatite particulates and the eggshell membrane fibres were uniformly distributed and contributed to the surface roughness of the scaffold. Biocompatibility and cytotoxicity of the novel constructs were assessed using the mouse-derived osteoblastic cell line, MC3T3-E1, and standard cell culture assays. Metabolic activity assessment (i.e. MTS assay), LDH-release profiles and Live/Dead staining demonstrated good cell adhesion, viability, and proliferation rates. Accordingly, this work summarises the successful development of a novel construct which may be exploited as a clinical/therapeutic treatment for bone repair as well as a possible translational application as a novel biomaterial for the drug development pipeline.