Physicochemical properties and biocompatibility of poly-ε-caprolactone filaments with naturally derived hydroxyapatite for 3D Printing

Abstract

Recent years, 3D printing is emerging as a promising technology for tissue regeneration by facilitating 3D cell culture giving the biomimetic surroundings. The purpose of this study was to evaluate the physicochemical properties and biocompatibility of poly-ε-caprolactone (PCL, Mw: 40,000) filaments with equine bone derived hydroxyapatite (EB) that is used as 3D printing materials. The specimen filaments were prepared in average diameter of 1.75 mm (±0.15) with 4 types by EB ratio of 0, 1, 5, and 10 %. The results showed that PCL filaments without EB had slightly higher ultimate tensile strength than with incorporated EB but it was insignificant at 5% level except PCL/EB (equine bone) 10%. Additionally, the elastic modulus of PCL filaments without EB was higher than that of EB incorporated PCL filaments but there was no significant diffrence. The EB containing PCL films were fabricated using solvent casting method for cell culture. To evaluate the biocompatibility and osteogenic behaviors on PCL films with nHAp, the human pulp-derived stem cells (DPSCs) were cultured. The results of 7 days of cell culture showed that the PCL film with weight ratio 0.1 EB enhances the DPCS proliferation. To assess the enhancement of osteogenic behavior by PCL films with EB, the DPSCs were cultured for four weeks under osteogenic media conditions. According to the protein assay results, the protein marker of DPSCs on a PCL film with 10% EB was observed higher tendency than that on other specimens. In conclusion, this study demonstrates the properties of PCL complex filaments with nEB can enhance osteogenic behavior of DPSCs.