Microgels for 3D Biofabrication

Abstract

While traditional bulk hydrogels have been widely used in 3D bioprinting for tissue engineering, engineered cell-loaded scaffolds still fall short of expectations because their nanoscale molecular networks impede cell function. Microgels, as micron-sized hydrogel materials, offer significant advantages in enhancing mass transport and tissue permeability, while concurrently promoting cellular proliferation, migration, and differentiation. Incorporating microgels as bioinks into 3D bioprinting enables customization of shape, mechanical properties, and functionality, significantly expanding the applications of hydrogel materials and addressing diverse bioprinting needs. Hierarchically porous scaffolds formed by microgel assembly leverage dual-scale porosity: nanoporosity inherent in the material and microporosity originating from the assembly. This unique structure promotes tissue regeneration and facilitates microtissue assembly. This review provides an overview of microgel fabrication techniques, describing their role as carriers for cells and biomolecules, as well as their applications in 3D biofabrication. Notably, we throughout present the application of microgels in 3D biofabrication. Finally, we provide an outlook on the potential applications of microgels in biomedical engineering and their integration with emerging printing technologies.

Keywords

3D biofabrication / 3D bioprinting / bioinks / microgels / tissue engineering

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