Biomimetic Mineralized Hydroxyapatite Nanofiber-Incorporated Methacrylated Gelatin Hydrogel with Improved Mechanical and Osteoinductive Performances for Bone Regeneration

Abstract

He Wang,1,* Bo Hu,1,* Hong Li,2 Ge Feng,1 Shengyuan Pan,1 Ziqi Chen,1 Bo Li,2 Jinlin Song1 1Stomatological Hospital of Chongqing Medical University, Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, People’s Republic of China; 2Chongqing Engineering Laboratory of Nano/Micro Biomedical Detection Technology, Chongqing University of Science and Technology, Chongqing, People’s Republic of China*These authors contributed equally to this workCorrespondence: Bo Li, Chongqing Engineering Laboratory of Nano/Micro Biomedical Detection Technology, Chongqing University of Science and Technology, Chongqing, 401331, People’s Republic of China, Tel [phone], Fax [phone], Email [email protected] Jinlin Song, College of Stomatology, Chongqing Medical University, 426# Songshibei Road, Yubei District, Chongqing, 401147, People’s Republic of China, Tel [phone], Fax [phone], Email [email protected]: Methacrylic anhydride-modified gelatin (GelMA) hydrogels exhibit many beneficial biological features and are widely studied for bone tissue regeneration. However, deficiencies in the mechanical strength, osteogenic factors and mineral ions limit their application in bone defect regeneration. Incorporation of inorganic fillers into GelMA to improve its mechanical properties and bone regenerative ability has been one of the research hotspots.Methods: In this work, hydroxyapatite nanofibers (HANFs) were prepared and mineralized in a simulated body fluid to make their components and structure more similar to those of natural bone apatite, and then different amounts of mineralized HANFs (m-HANFs) were incorporated into the GelMA hydrogel to form m-HANFs/GelMA composite hydrogels. The physicochemical properties, biocompatibility and bone regenerative ability of m-HANFs/GelMA were determined in vitro and in vivo.Results: The results indicated that m-HANFs with high aspect ratio presented rough and porous surfaces coated with bone-like apatite crystals. The incorporation of biomimetic m-HANFs improved the biocompatibility, mechanical, swelling, degradation and bone regenerative performances of GelMA. However, the improvement in the performance of the composite hydrogel did not continuously increase as the amount of added m-HANFs increased, and the 15m-HANFs/GelMA group exhibited the best swelling and degradation performances and the best bone repair effect in vivo among all the groups.Conclusion: The biomimetic m-HANFs/GelMA composite hydrogel can provide a novel option for bone tissue engineering in the future; however, it needs further investigations to optimize the proportions of m-HANFs and GelMA for improving the bone repair effect.Keywords: biomimetic composite hydrogel, mineralized hydroxyapatite nanofiber, GelMA, bone regeneration

Keywords

• biomimetic composite hydrogel
• mineralized hydroxyapatite nanofiber
• gelma
• bone regeneration.