3D bioprinted piezoelectric hydrogel synergized with LIPUS to promote bone regeneration

Bone defects resulting from trauma, tumor resection, non-union of fractures, and infections present enormous challenges in treatment. Although three-dimensional (3D) bioprinting plays an important role in repairing bone tissues, the lack of mechanical properties and osteoinductive ability of the bioinks remains a barrier for the application of the technology. In this study, we used advanced 3D bioprinting technology to create a novel piezoelectric hydrogel scaffold (Gel/PBT@BMSCs) which consisted of bone marrow-derived mesenchymal stem cells (BMSCs), gelatin methacryloyl (GelMA), and polyethylene glycol (PEG)-modified barium titanate (BT) nanoparticles. The piezoelectric hydrogel scaffold provided a stable 3D microenvironment for cell growth and adhesion, enhancing cell viability and osteogenic activity when subjected to low-intensity pulsed ultrasound (LIPUS) stimulation. Furthermore, <i>in vivo</i> experiments demonstrated that the innovative hydrogel scaffold significantly accelerated the healing process of bone defects and exhibited impressive bone regeneration capabilities. These findings highlight the potential of piezoelectric hydrogel for further research and application in the field of bone tissue engineering, and offer new approaches for the treatment of bone defects.