Preparation of Microvasculature-embedding Porous Hydrogels for 3D Cell Culture

Although various types of hydrogel-based 3D cell culture platforms have been developed, it is difficult to prepare porous hydrogels encapsulating intact cells and having capillary networks with a one-step procedure. Here we propose a facile strategy to prepare microvasculature-embedding porous hydrogels for 3D cell culture, utilizing an aqueous two-phase dispersion system. We used an aqueous solution of photo-crosslinkable gelatin (GelMA) and polyethylene glycol (PEG) to form an aqueous two-phase dispersion system. A bi-continuous state was generated by re-mixing these two phases at a proper mixing ratio, and a sponge-like, porous hydrogel could be formed by selectively crosslinking the GelMA-rich phase via UV irradiation. We successfully encapsulated mammalian cells in the hydrogel matrix with a high cell viability, and confirmed that the porous hydrogel was superior to homogeneous hydrogels for cell culture. The presented hydrogel would be applicable to 3D-cell culture for various types of biomedical applications.