Extended Data Fig. 9: Simulation setup and results for BSA-valves and a device image.

a, Boundary conditions for the simulation. b, Water saturation at the outlet (right) for BSA loading concentrations (w/v, 1 μL) of 0%, 1%, 2%, and 3%. c, Simulated progression of water saturation (blue) and BSA dissolution (red) for valves with 3% BSA, 2% BSA, and 1% BSA. d, Fully integrated system incorporating paper-based microfluidics, electrochromic timing elements, and LFAs to facilitate and characterize the time-dependent collection and chemical analysis of sweat. Scale bar, 10 mm.