One‐Step Generation of Porous GelMA Microgels by Droplet‐Based Chaotic Advection Effect

Abstract Porous GelMA microgels are promising scaffolds for biomedical research and regenerative medicine due to their special topology, cell‐loading capacity, and high biocompatibility. However, the traditional preparation of porous microgels is often limited by some complex postprocessing processes such as freeze‐drying and swelling equilibrium. Herein, we present a simple strategy for in situ generation of porous GelMA microgels as cell carriers by integrating the placeholder of polyethylene oxide (PEO) and chaotic advection effect of droplets in microfluidic devices. The device is mainly composed of four functional units, including droplet generation, rapid mixing, photopolymerization, and collection. The strategy allows precise control of the size and porosity of the microgels by changing the flow rates of the continuous and dispersed phases. Furthermore, both human mesenchymal stem cells (hMSCs) and umbilical vein endothelial cells (HUVECs) cultured on the surface of obtained microgels show high cell viability, spreading, and proliferation, which indicate their good biocompatibility and potential as microcarriers for various cell types. The proposed strategy provides a novel approach for the preparation of porous microgels holding promise in tissue engineering and scalable cell expansion.