Rationally designed biomimetic bone scaffolds with hierarchical porous-architecture: Microstructure and mechanical performance

Abstract

A biomimetic strategy was adopted by incorporating nano-fluorcanasite (nFC) within biocompatible and biodegradable poly-(ε-caprolactone) (PCL) matrix to obtain functionally tuned bio-nanocomposite bone scaffolds. A hybrid approach was adopted using fused deposition modelling, solvent casting and thermally induced phase separation to develop the scaffolds. Phase evolution study through X-ray diffraction revealed dominant crystalline phases (fluorcanasite and fluorapatite) and enhanced crystallinity of the scaffolds. Microstructural investigation through field emission-scanning electron microscopy revealed interconnected gradient porosities and hierarchical (meso, micro and macro) porous architecture within the scaffolds similar to natural bone. The elemental mapping study further confirmed higher calcium:phosphate (Ca:P) ratio upon nFC incorporation, desirable for bone repair. The volume visualisation through X-ray micro-computed tomography confirmed the presence of porous micro-architecture and homogenous dispersion of nFC particulates within the scaffolds. Mechanical performance of the bio-nanocomposite scaffolds was also found to be enhanced to sustain the load against pore collapse. Enhanced cell viability and cellular proliferation response with human osteosarcoma bone cells established the in-vitro biocompatibility of the scaffolds. Finally, this study opens up a unique pathway in the fabrication of biomimetic bone scaffolds with a highly conducive cellular environment.

Keywords

• biopolymers, biocomposites
• bone scaffold
• biomimetic
• additive manufacturing
• bone tissue engineering