Photocrosslinked Gelatin Methacryloyl (GelMA)/Hyaluronic Acid Methacryloyl (HAMA) Composite Scaffold Using Anthocyanidin as a Photoinitiator for Bone Tissue Regeneration

Gelatin and hyaluronic acid are natural biopolymers that are important components of soft tissues in the human body, and both have been used in several biomedical applications. To achieve controllable mechanical and degradation properties of gelatin and hyaluronic acid, methacrylic acid has been used to modify photocrosslinkable gelatin methacryloyl (GelMA) and hyaluronic acid methacryloyl (HAMA). Irgacure 2959 (I2959) and anthocyanidin have been used as photoinitiators for comparison. Finally, the photocrosslinked GelMA/HAMA composite scaffold has been prepared for bone tissue regeneration. The composite scaffolds were prepared using mold casting and photocrosslinking techniques. Specific ratios of GelMA and HAMA reagents were mixed properly with I2959 or anthocyanidin photoinitiators. Samples were examined with chemical and material, in vitro, and in vivo evaluations. Furthermore, two photoinitiators, I2959 and anthocyanidin, can crosslink the GelMA/HAMA composite scaffold. A 1% HAMA incorporation can significantly decrease the degradation of the GelMA/HAMA scaffold compared with GelMA only. Also, HAMA participation can improve cell viability and promote bone-related cell differentiation and tissue regeneration (bone formation) without any apparent adverse reactions in vivo.