HYDRA is an automated platform for fabricating thin, planar hydrogel films directly inside standard multiwell plates. By combining robotic liquid handling with soft, biomimetic substrates, HYDRA overcomes the meniscus and imaging limitations of conventional hydrogel casting while remaining compatible with high-content microscopy and screening workflows. In our work, HYDRA supported long-term holographic imaging, fluorescence-based drug assays, and live-cell tracking on compliant substrates, offering a practical bridge between physiological relevance and scalable in vitro drug testing.

1) HYDRA method
A liquid-handling robot dispenses and immediately re-aspirates hydrogel precursor from each well, leaving behind a thin residual layer that crosslinks into a planar hydrogel film. This automated step prevents wall wetting and meniscus formation, generating imaging-compatible substrates directly in standard high-throughput plates.

2) HYDRA drug testing
Comparison of nocodazole response on conventional plastic versus compliant HYDRA substrates during long-term imaging. Human keratynocytes (HaCaT) were tracked over time across increasing drug concentrations on soft and rigid environments. HYDRA enables long-term imaging even when cells are cultured on a hydrogel substrate.

3) HYDRA cell-cycle imaging
Live fluorescence imaging of engineered HaCaT cells on HYDRA hydrogels captures cell morphology together with cell-cycle progression over time. Actin is shown in gray, G1-phase nuclei in cyan, and S/G2-phase nuclei in magenta, illustrating how HYDRA supports high-resolution tracking of proliferative behavior on soft, imaging-compatible substrates.