Biomimetic Dual-Sensing Bone Scaffolds: Characterization and In Vitro Evaluation Under Dynamic Culturing Conditions

The regeneration of large segmental bone defects remains a significant challenge. While electrical stimulation has demonstrated the potential to accelerate bone healing, clinical translation has been hindered by the lack of safe, localized delivery methods. In this study, we present a novel strategy combining piezoelectric and electrically conductive polymers with allograft demineralized bones to create stimuli-responsive, biologically relevant scaffolds via pneumatic 3D printing. These scaffolds exhibit enhanced piezoelectric potential and tunable electrical properties, enabling both electrical and mechanical stimulation of cells (without external stimulators). Under dynamic culturing conditions (i.e., ultrasound stimulation), human bone marrow-derived mesenchymal stromal cells cultured on these scaffolds displayed significantly elevated osteogenic protein expression (i.e., alkaline phosphatase and osteocalcin) and mineralization (confirmed via xylenol orange mineral staining) after two weeks. This work introduces a bioinspired, printable ink in conjunction with a simple fabrication approach for creating dual-responsive scaffolds with high potential for functional bone tissue regeneration.