Biomimetic Synthetic Mineralized Collagen Scaffolds For Repair Of Jaw Defects

Mineralized collagen scaffolds hold great promise for bone defect repair. There are still challenges in bionic natural bone collagen intrafibrillar mineralization. This study aims to develop a safer biomimetic co-assembly strategy to synergistically regulate collagen fibrillogenesis and mineralization to create functionally enhanced scaffolds for jaw defect reconstruction. A non-collagen analogue (polyaspartic acid, PAsp) and calcium ion complex (PAsp-Ca) were co-assembled with collagen molecules, and the effect of this process on the morphology, properties and mineralization of collagen fibrils was investigated. Collagen fibers were characterized by atomic force microscopy (AFM) and transmission electron microscopy (TEM). The mineralized collagen fibers were obtained and made into scaffolds. The morphology of the mineralized collagen scaffolds was characterized by scanning electron microscopy (SEM). Scaffold osteogenic effects were evaluated using Sprague Dawley Rat Bone Marrow Mesenchymal Stem Cells (SD BMSCs) (n=3) and rat mandibular defect models (n=3). Statistical analyses included Shapiro-Wilk normality verification followed by repeated measures ANOVA with Tukey post-hoc testing (α=0.05). PAsp-Ca co-assembly increased collagen fiber diameter and improved mechanical properties compared to control conventional assembly. The co-assembled collagen fibers were mineralized faster and to a higher degree than the control. The obtained mineralized collagen fiber scaffolds showed osteogenesis-promoting effects both in vivo and in vitro. Co-assembly of PAsp-Ca with collagen molecules promotes the assembly and mineralization of collagen fibrils. The mineralized collagen scaffolds obtained in this way promote bone defect repair.