A research team led by Professor Hyung Joon Cha of POSTECH Department of Chemical Engineering and Convergence Graduate School of Science and Technology with a major in Medical Sciences, together with Dr. Jinyoung Yun and Integrated Program student Hyun Taek Woo of the Department of Chemical Engineering has developed an innovative injectable adhesive hydrogel for bone regeneration. This hydrogel uses harmless visible light to simultaneously achieve cross-linking and mineralization without the need for bone grafts. The groundbreaking research was recently published online at Biomaterials.
Bone defects, which arise from various causes such as trauma, infections and congenital anomalies, are increasingly common in aging societies. Conventional treatments usually involve bone grafts combined with serum or bioadhesives to fill the defect. However, existing injectable hydrogels face challenges such as difficulty maintaining their shape inside the body and limited adhesive strength. Furthermore, traditional methods using bone grafting with adhesive materials often fail to achieve simultaneous “bone regeneration” and “adhesion.”
The POSTECH team has introduced a novel system that addresses these limitations. This new hydrogel system uses visible light, safe for the human body, to facilitate cross-linking, where the main components of the hydrogel bond and harden, and to simultaneously increase mineralization, where bone-forming minerals such as calcium and magnesium are formed. phosphate within the hydrogel. While previous studies explored the use of light in similar applications, they found problems such as the need to separately prepare and mix bone grafts and adhesive materials, as well as weak bonding of the main components, which often degraded with exposure. time.
The newly developed hydrogel precursor comprises alginate (natural polysaccharide derived from brown algae), 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. After irradiation with visible light, cross-linking occurs and at the same time amorphous calcium phosphate is formed, which functions as a bone graft material. This eliminates the need for separate bone grafts or adhesives, allowing the hydrogel to provide both bone regeneration and adhesion.
In experiments using animal models with femoral bone defects, the hydrogel was successfully injected, adhered precisely, and effectively delivered components essential for 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 be a breakthrough in bone tissue regeneration technology.”
This research was supported by the Dental Medical Technology Research and Development Project of the Ministry of Health and Welfare and the Integrated End-to-End Medical Device R&D Project.