Smart-Responsive Multifunctional Therapeutic System for Improved Regenerative Microenvironment and Accelerated Bone...

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Tissue Engineering

Background:

• Bone defect treatment faces challenges in controlling the local immune environment, blood vessel formation, and bone cell differentiation.
• Existing therapies lack spatiotemporal control over these critical regenerative processes.

Purpose of the Study:

• To develop a smart-responsive hydrogel system for enhanced bone regeneration.
• To investigate the potential of deferoxamine (DFO)-loaded black phosphorus nanosheets within a hybrid hydrogel for accelerated bone healing.

Main Methods:

• Preparation of DFO-loaded black phosphorus nanosheets coated with polydopamine (BPPD) and incorporation into a gelatin methacrylate/sodium alginate methacrylate (GA) hydrogel.
• Utilizing near-infrared (NIR) light for photothermal therapy and stimuli-responsive release of DFO and phosphate ions.
• Evaluating the hydrogel's effects on osteogenesis, angiogenesis, reactive oxygen species (ROS) scavenging, and macrophage polarization in vitro and in vivo.

Main Results:

• The GA/BPPD hydrogel demonstrated dual NIR/pH responsiveness, enabling controlled release of therapeutic agents.
• NIR photothermal therapy promoted osteogenesis and angiogenesis, reduced ROS, and polarized macrophages to the M2 phenotype.
• In vivo studies showed accelerated bone healing, reduced inflammation, enhanced pro-healing factor secretion, and improved revascularization.

Conclusions:

• The intelligent photothermal hydrogel platform effectively modulates the osteoimmune microenvironment.
• This approach promotes angiogenesis and osteogenesis, offering a promising strategy for augmented bone regeneration.