A 3D-Printed Composite Hydrogel Engineered with a Coordination-Reprogrammed Nanozyme for Synergistic Chemo-Physical...

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Nanotechnology

Background:

• Diabetic bone regeneration is hindered by excessive reactive oxygen species (ROS) and inflammation.
• Current treatments face challenges in effectively addressing the complex pathological microenvironment in diabetic bone defects.

Purpose of the Study:

• To engineer a hierarchical 2-dimethylimidazole (Hmim)/polydopamine (PDA) composite integrated into a 3D-printed hydrogel scaffold.
• To develop a chemo-physical therapeutic strategy for enhancing diabetic bone regeneration.

Main Methods:

• Fabrication of the Hmim/PDA composite via in situ polymerization to optimize cobalt loading and superoxide dismutase (SOD)-like activity.
• Integration of the composite into a 3D-printed hydrogel for localized, sustained release.
• Application of near-infrared (NIR) irradiation to leverage PDA's photothermal effect.

Main Results:

• The composite demonstrated enhanced SOD-like activity, effectively scavenging ROS.
• The hydrogel scaffold facilitated M2 macrophage polarization, correcting the inflammatory microenvironment.
• Combined chemo-physical therapy promoted osteogenesis and vascularization in diabetic bone defects.

Conclusions:

• The developed composite-based 3D-printed platform offers a promising chemo-physical strategy for diabetic bone regeneration.
• This approach effectively addresses ROS and inflammation while stimulating bone healing and vascularization.