Ultrasound‐Triggered Mg²⁺ Blasting Release Hydrogel Microspheres for Promoting Bone Reconstruction

Abstract

Mg2+ (Magnesium ion) can affect bone tissue metabolism by regulating related signaling pathways in bone metabolism. However, how to realize precise controlled release of Mg2+ in bone regeneration treatment still presents a challenge. Herein, for the first time, the GelMA‐BP (Gelatin Methacryloyl‐Bisphosphonate) and the composite nano‐bubble system are fused to construct the Mg2+ blasting controlled‐release hydrogel microspheres, the stability of the nano‐bubbles in the microspheres is enhanced through metal coordination complexation, and the burst of the nano‐bubbles is controlled by using ultrasonic cavitation to achieve the precise controlled release of Mg2+, ultimately effectively promoting bone reconstruction. First, GelMA‐BP composite is prepared by Schiff base reaction. Second, the nanobubble BP (Bisphosphonate) system is constructed, and Mg2+ is combined with the ligand coordination to prepare the composite nanobubble system. Thirdly, through Mg2+ co‐coordination, the ultrasound‐triggered Mg2+ blasting controlled release microspheres were prepared to achieve bone repair. Overall, this innovative strategy effectively solves the problem of accurate controlled release of Mg2+, and finally effectively activates in situ bone tissue regeneration.