Mechanical regulation and 3D bioprinting of native tissue-inspired granular composite hydrogels
摘要
Granular composite (GC) hydrogels have attracted considerable interest in biomedical applications due to their versatile printability and exceptional mechanical properties. However, the lack of comprehensive design guidelines has limited their optimal engineering, as the factors influencing their mechanical performance and printability remain largely unexamined. In this study, we developed GC hydrogels by integrating microgels with interstitial matrices of photocrosslinkable gelatin methacrylate (GelMA). We utilized confocal microscopy and nanoindentation analyses to investigate the spatial distribution and mechanical behavior of these hydrogels. Our findings indicate that the mechanical and rheological properties of GC hydrogels can be precisely tailored by adjusting the volume fraction and size of the microgels. Furthermore, hydrogen bonds were identified as significant contributors to compressive performance, although they had minimal effect on cyclic mechanical behavior. Compared to bulk GelMA hydrogels, GC hydrogels demonstrated enhanced printability and remarkable superelasticity. As a proof of concept, we illustrated their dual printability in embedded printing to create prosthetic liver models for preoperative planning. This study provides valuable insights into the design and optimization of GC hydrogels for advanced biomedical applications.