Surface modification of 3D-printed polylactic acid-hardystonite scaffold for bone tissue engineering

This study aims to synthesize hardystonite bioceramic powder using the sol-gel method and fabricate composite scaffolds of poly lactic acid (PLA)-hardystonite (Har) with different ceramic contents (0, 10, 20, and 30 wt%) through melt-based 3D-printing. X-ray diffraction (XRD) analysis of the ceramic powder and composites indicated that the characteristic peaks matched well with peak intensities increasing proportionally with the ceramic content in the composites. Porosity measurement using the Archimedes method revealed an increase in pore size and overall porosity with increasing Har content of the composite. Compression testing on 3D-printed composite scaffolds demonstrated that the compressive strength of the scaffolds increased from 25.9 ± 0.1 MPa for pure PLA scaffolds to 34.5 ± 2.1 MPa for PLA-20Har (scaffolds containing 20 wt% Har), while PLA-30Har scaffolds exhibited a decrease in compressive strength of approximately 10 %. Tensile testing on rigid 3D-printed composite samples indicated optimal mechanical properties for PLA-30Har composite. Additionally, the water contact angle decreased with higher ceramic content, from 71.9 ± 4.1° for pure PLA to 57.9 ± 3.1° for PLA-30Har, indicating improved wettability. The scaffolds exhibited favorable biocompatibility, biodegradability, and enhanced cell adhesion with higher ceramic content. Surface modification of the optimal scaffold (PLA-20Har) significantly reduced the water contact angle and further improved cell adhesion. These results suggest that these biocompatible scaffolds have strong potential for applications in bone tissue engineering.