Force-Electric Nanotentacles of Tantalum Implant Accelerate Cellular Energy Metabolism/Crosstalk for Immunomodulation-Vascularized Bone Integration.

Current load-bearing bone implants primarily serve as static structural supports, still fall short of replicating the dynamic, spatiotemporal, and multifunctional coordination inherent in natural bone regeneration. Herein, we first develop a biomimetic force-electric responsive tantalum (Ta) implant with surface-nanostructured LiTaO3 (n- LiTaO3) via combining laser nanofabrication and Li+-induced in situ reaction, achieving favorable immunomodulation-mediated vascularized osseointegration under low-intensity pulsed ultrasound stimulation. The piezoelectric LiTaO3 nanotentacles convert ultrasound vibration into localized electrical signals, triggering Ca2 + influx, accelerating mitochondrial ATP production, and activating PI3K-AKT signaling pathway in BMSCs to promote osteogenesis. It also orchestrates a pro-osteoregenerative immune microenvironment through M2 macrophage polarization and immune-osteogenic crosstalk mediated by ECM-integrin-FAK axis. The force-electric response implant yet promotes angiogenesis mainly via enhancing intracellular Ca2 +-dependent eNOS/NO cue and cellular metabolism, reduces the inflammatory response in the dorsal subcutaneous tissue of rats, and further promotes vascularization and bone integration in femoral defects. The novel force-electric response Ta implant endows real-time controllable regulation of multifunctional tissue regeneration for using as patient-personalized load-bearing osteoarticular prostheses.