Microfluidic hanging-drop platform for parallel closed-loop multi-tissue experiments

We present a new on-chip pumping approach for microfluidic hanging-drop networks that are used for experiments with 3D microtissue spheroids. The pump includes a pneumatic chamber located directly above one of the hanging drops and uses the liquid-air-interface for flow-control. With this approach several independent hanging drop networks (HDN) can be operated in parallel with only one single pneumatic actuation line. The pump concept enables closed-loop medium circulation between different organ models for body-on-a-chip applications and allows for multiple simultaneous assays in parallel.