fig5

Figure 5. (A-C) ΔR/R₀ of the PAM/COS@SIW hydrogel-based wearable sensors in response to (A) finger bending at different angles, (B) cyclic wrist bending at the same angle, and (C) cyclic mouth opening and closing at the same degree; (D) Optical photograph of ECG monitoring using a three-electrode configuration; ECG signals recorded by commercial Ag/AgCl electrodes and PAM/COS@SIW hydrogel electrodes during (E) the static state and (F) motion; (G) Optical photograph of EMG monitoring using a three-electrode configuration. All optical photographs (A-D and G) were taken by the authors using personal mobile devices; (H) EMG signals recorded under different grip forces (5, 15 and 30 kg) by commercial Ag/AgCl electrodes and PAM/COS@SIW hydrogel electrodes; (I) EMG signals recorded by commercial Ag/AgCl electrodes and PAM/COS@SIW hydrogel electrodes when lifting different loads (1, 3.5 and 5 kg). PAM: Polyacrylamide; COS: chitosan oligosaccharide; SIW: silicotungstic acid; ECG: electrocardiogram; EMG: electromyography.