Polydopamine Coating in Trabecular Bone-Like Scaffolds With Strontium-Substituted Nanohydroxyapatite for Bone Tissue Engineering

Abstract

Bone fractures can be effectively treated through the utilization of supportive structures for tissue growth: the scaffolds. Strontium-substituted hydroxyapatite (HASr) is a promising ceramic improving bone regeneration. However, composite scaffolds made from PLA and hydroxyapatite lack optimal surface properties. Polydopamine (PDA) exhibits potential for functionalizing biomaterials surfaces by providing ideal physical–chemical properties for cell adhesion. This study proposes applying a PDA coating on PLA/HASr scaffolds to enhance their physico-chemical properties for use as biomaterials in bone engineering applications. Fused Filament Fabrication 3D printer was used to produce scaffolds with trabecular bone-inspired geometry using a digital model based on the cell bone dynamics. Wettability analysis demonstrated that PLA/HASr/PDA scaffolds exhibited improved hydrophilicity (31.2° ± 5.8°) compared to neat PLA (88.3° ± 0.4°). These scaffolds exhibit several characteristics suitable for bone tissue engineering applications, such as enhanced release of signaling ions (Ca2+ and Sr2+ ions from modified hydroxyapatite) and potential improved cell adhesion properties.