Bone defects are extremely common and may arise from several causes, such as trauma, infection, and accidents. Conventional treatments typically involve bone grafts combined with serum or bioadhesives to repair defects.
However, current injectable hydrogels face challenges like difficulty retaining their shape in the body and limited adhesive strength. Additionally, traditional approaches using bone grafts with adhesive materials often struggle to achieve both effective “bone regeneration” and strong “adhesion” simultaneously.
A research team at POSTECH has recently introduced an innovative injectable adhesive hydrogel for bone regeneration. This hydrogel uses harmless visible light to allow crosslinking and mineralization without bone grafts.
In crosslinking, the main components of the hydrogel bond and harden, and in mineralization, bone-building minerals like calcium and phosphate form within the hydrogel.
The newly synthesized hydrogel precursor comprises alginate, mussel adhesive protein containing RGD peptide, calcium ions, phosphonodiols, and a photoinitiator. The coacervate-based formulation, which is immiscible in water, ensures that the hydrogel retains its shape and position after injection into the body.
Upon visible light irradiation, crosslinking occurs, and amorphous calcium phosphate, which functions as a bone graft material, is simultaneously formed. This eliminates the need for individual bone grafts or adhesives, allowing the hydrogel to provide bone regeneration and adhesion.
This means that, for instance, in experiments utilizing animal models with femoral bone defects, the hydrogel was successfully injected; it adhered precisely and adequately delivered components vital to bone regeneration.
Professor Cha commented, “The injectable hydrogel system for bone regeneration developed by our research team represents an innovative alternative to conventional complex treatments for bone diseases and will greatly advance bone tissue regeneration technology.”
Journal Reference:
- Jinyoung Yun, Hyun Tack Woo, Sangmin Lee, Hyung Joon Cha. Visible light-induced simultaneous bioactive amorphous calcium phosphate mineralization and in situ crosslinking of coacervate-based injectable underwater adhesive hydrogels for enhanced bone regeneration. Biomaterials. DOI: 10.1016/j.biomaterials.2024.122948
