Fig. 5. Adhesion performance of bioinspired surface in the application of bio-signal monitoring.

(A) Schematic illustration of detecting pulse signals with the bioinspired NFPF skin patch combined with a piezoelectric sensor. Pulse signals can be distinguished with a wider range of interfacial liquid volume on the bioinspired surface than that of a smooth surface patch, which shows that the bioinspired surface has stronger water tolerance for signal detecting. (B) Testing flow tolerance of bioinspired and smooth surface patches in flowing water (Q ≈ 90 ml cm⁻² s⁻¹) on a wet forearm shows that the bioinspired surface patch can steadily adhere to wet human skin.