Electrospun Poly-D-L-lactic acid fibrous scaffolds as a delivery vehicle for calcium phosphate salts to promote in situ mineralisation and bone regeneration

Abstract

Polymeric scaffolds and calcium phosphate cements have both shown promise in treating bone defects, whereby the former facilitates cell-mediated repair over long periods, while the latter facilitates rapid defect filling but is limited by poor cell remodeling. Therefore, the goal of this study was to combine these key technologies to develop a polymer-ceramic hybrid, maintaining the advantages of these techniques while overcoming their limitations. To achieve this we used electrospinning to produce Poly-D-L-lactic acid fibrous scaffolds containing Tetracalcium and Dicalcium Phosphate particles of tailored concentrations/sizes to maintain solution stoichiometry favoring in situ Hydroxyapatite precipitation. Poly-D-L-lactic acid scaffolds containing high concentrations of Calcium Phosphate up to 50% Calcium Phophate (w/w) were successfully fabricated, demonstrating a fibrous, porous, bone biomimetic microarchitecture with excellent mechanical properties, that undergoes rapid mineralization in physiological environments and is biocompatible promoting stem cell adhesion. This polymer-ceramic hybrid therefore represents an enhanced strategy to enhance bone repair.