Mimicking Human Perspiration: A Layered Microfluidic Skin Phantom With Tunable Hydrodynamics

ABSTRACT Wearable sweat‐sensing technologies offer a non‐invasive and patient‐friendly route toward near‐patient diagnostics, yet their development is hindered by the lack of realistic test platforms that reproduce human perspiration dynamics. Artificial skin phantoms capable of mimicking physiological sweat generation could substantially reduce development time and reliance on human testing. Here, a 3D multilayer artificial skin phantom is introduced that emulates eccrine sweat glands through stacked Flexdym microchannels with tunable poly(vinyl alcohol)–induced wettability contrast. The platform combines soft lithography, thermal imprinting, and surface treatments to replicate pore geometry and to precisely control hydraulic resistance (≈2.62 × 10 1 5 Pa s m − 3 ). The system further reproduces pulsatile flow rates of approximately 3 nL min −1 per pore, closely matching reported physiological eccrine sweat secretion. The resulting skin phantom enables scalable and reproducible simulation of low‐rate perspiration and overcomes limitations of existing membrane‐based or static microchannel models. This platform provides a versatile preclinical testbed for the evaluation of wearable sweat sensors, transdermal delivery patches, skin‐adherent materials, and cosmetic or therapeutic formulations. Future integration of embedded sensing elements and localized flow control is expected to support real‐time diagnostic assessment and transdermal testing under dynamic conditions.