Macro- and micromechanical behaviors of poly(lactic acid)–hydroxyapatite electrospun composite scaffolds

It was demonstrated that the macro- and micromechanical behaviors of electrospun composite scaffolds based on PLA and HA can be simultaneously studied using 3D digital image correlation strain measurements coupled with an axial tensile test. It was proven that the addition of a small quantity (2%) of HA particles into PLA electrospun scaffolds decreased their mechanical properties by approximately 40 and 60% at the micro- and macroscales, respectively; nevertheless, when this amount was increased beyond 2% of HA, the composites recovered their stiffness, showing Young’s moduli ranging between 400 and 600 MPa. Hence, the mechanical responses of PLA–4% HA and PLA–6% HA electrospun scaffolds were conveniently enhanced with the addition of hydroxyapatite nanoparticles. The micromechanical measurements were able to capture the microstrain mechanism between electrospun nanofibers and the effect of HA nanoparticles on their mechanical response. This methodology could be a powerful tool for developing scaffolds for specific applications in tissue engineering.