Biofunctionalized 3D-printed gelatin-alginate scaffolds with arginine-glycine-aspartic acid (RGD) peptides for enhanced in vitro osteogenesis.

Background/purpose: Alveolar bone defects are difficult to treat due to ongoing resorption and limitations of conventional grafts. Tissue engineering strategies, particularly 3D hydrogel-based scaffolds, offer promising alternatives by mimicking the extracellular matrix and supporting cell-driven regeneration. This study aimed to incorporating arginine-glycine-aspartic acid (RGD) peptides into 3D-printed gelatin-alginate hydrogels to enhances their bioactivity and osteogenic potential for effective alveolar bone repair. Materials and methods: The physical characterization of RGD peptides-grafted 3D-printed gelatin-alginate scaffolds was conducted using morphological observation, elemental composition analysis, Fourier-transform infrared spectroscopy (FTIR), and assessments of swelling and degradation behavior. Biological performance was examined in vitro through cell adhesion, proliferation, differentiation (proven by alkaline phosphatase activity), and mineralization (proven by Alizarin red S staining) using MG-63 osteoblastic-like cells. Results: RGD peptides-grafted 3D-printed gelatin-alginate scaffolds exhibited a porous architecture. Elemental and FTIR analyses confirmed successful peptide incorporation through elevated nitrogen and oxygen content, along with amide and C-H stretching bands. The scaffolds showed stable swelling, reduced degradation, and significantly enhanced MG-63 cell adhesion, proliferation, ALP activity, and mineralization, particularly in the 0.5 mg/mL RGD peptides-grafted group. Conclusion: RGD peptides modification significantly enhances the structural and biological performance of 3D gelatin-alginate scaffolds, reinforcing their potential as effective materials for alveolar bone regeneration.