Fig. 1: Device design and overview of organoid and cell configurations.

a Computer-aided design (top) and photographs (bottom) of the microfluidic chip displaying 10 microchannels, with each microchannel featuring a trapping site. b Top view of the microfluidic device. A syringe pump was connected to the outlet of the channel to introduce fluid perfusion. c Schematic diagram and photograph of the parallelization feature of our setup, showcasing 10 microchannels controlled simultaneously. d Photograph of the microfluidic chip and schematic three-dimensional view of the U-cup shaped area functioning as a trap. Here, the trap site is exemplarily occupied by a cell aggregate. e Schematic diagram showing an overview of the loading process. Initially, the hydrogel containing an organoid and HUVEC cells was introduced. Before polymerization of the hydrogel, air was introduced to position the hydrogel and the HUVEC cells. Finally, growth medium was introduced for continuous perfusion of the microfluidic chamber and the trapped organoid. f Schematic 3D and cross-sectional views of the microchannel showing the air loading process and associated hydrogel deposition. g Experimental cross-sectional view (left) of the microfluidic channel showing the hydrogel deposition in the trap and in the channel’s corners and 3D rendering (right), taken with an in-house light sheet fluorescence microscopy set-up. h Representative images of vascular spheroid/organoid cultured in fibrin (left), and hiPSC-derived lung organoids cultured in Matrigel, showing efficient trapping and robust growth over 2 weeks on-chip (right).