Large-Scale Production of Uniform, Small Adipocyte Spheroids in Hydrogel Microcapsules Using a Microfluidic Flow-Focusing Device

Adipocyte spheroids offer a promising three-dimensional (3D) cell culture model for obesity research, as they reproduce the structure and cell-cell interaction of adipose tissue more accurately compared to two-dimensional (2D) cultures. However, the mass production of uniform, small adipocyte spheroids remains challenging, limiting their use in large-scale analyses, such as drug screening. Here, we develop a method that combines simple microfluidics with templated emulsification to enable the large-scale production of small, uniform adipocyte spheroids. By encapsulating preadipocytes in hollow agarose microcapsules and incubating them for 2 days, we reproducibly generated more than 100,000 uniform spheroids with diameters of approximately 60 μm. These preadipocytes were subsequently differentiated into adipocyte spheroids through an 8-day induction period. This platform facilitates large-scale 3D analysis for obesity research and can be adapted to produce various other spheroid and organoid models, broadening its utility in biomedical research.