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Functional-responsive hydrogel microspheres based on microenvironment sensing promote the sequential repair of
Xinyu Zhang1,2, Fan Wang3, Xinhe Li1,2
1Department of Rehabilitation Medicine, Key Laboratory of Physical Medicine and Precision Rehabilitation of Chongqing Municipal Health Commission, The First Affiliated Hospital of Chongqing Medical University, No.1 Youyi Road, Yuzhong District, Chongqing, 400010, P. R. China.
This study developed a novel hydrogel microsphere that senses microenvironmental pH changes to regulate reactive oxygen species (ROS) for treating infectious bone defects. The system achieves sequential anti-infection and bone repair, enhancing therapeutic outcomes.
Area of Science:
- Biomaterials Science
- Regenerative Medicine
- Nanotechnology
Background:
- Treating infectious bone defects (IBD) requires precise regulation of reactive oxygen species (ROS) for sequential anti-infection and osteogenesis.
- Current challenges lie in sensing microenvironmental changes to effectively control ROS levels.
- A novel nanoparticle system integrated into a hydrogel microsphere was developed for microenvironment sensing and ROS regulation.
Purpose of the Study:
- To create a functional-responsive hydrogel microsphere capable of sensing microenvironmental pH changes.
- To achieve a "anti-infective first, then osteogenesis" temporal sequential repair strategy for IBD.
- To regulate ROS balance for synergistic bone defect repair.
Main Methods:
- Preparation of PBD-ICG nanoparticles using a "triple-element synergy" acid-base-driven assembly method.
- Loading nanoparticles onto GelMA/HAMA hydrogel microspheres to form a functional-responsive hydrogel microsphere (PGI).
- Utilizing ultrasonic cavitation to induce ROS generation and pH-responsive drug release (deferoxamine) for ROS inhibition.
Main Results:
- The PGI system demonstrated pH-sensing capabilities, transitioning the microenvironment from acidic to weakly alkaline.
- Ultrasound-induced ROS generation achieved 74% antibacterial efficacy, while deferoxamine inhibited excess ROS with 72% efficiency.
- In vitro angiogenesis increased 9.19-fold, and in vivo studies showed 82.6% antibacterial efficacy and 46.5% improved osteogenesis.
Conclusions:
- The developed system effectively regulates ROS balance via microenvironment sensing for functional-responsive, temporal sequential repair.
- This approach offers novel strategies for synergistic treatment of infectious bone defects.
- The PGI hydrogel microsphere system shows significant potential for advancing IBD therapy.
