Fig. 3: ECG signal detection and cytotoxicity verification of carbon-based tape.

a Schematic diagram of the placement of SETs. b Comparing the real picture of commercial Ag/AgCl gel electrodes and PU-SET. c Comparison of ECG signals detected by commercial Ag/AgCl gel electrodes and PU-SET. The gray curve and the red curve are the ECG signals detected by SET on channel 1 and channel 2 respectively. The green curve is the ECG signals detected by the commercial Ag/AgCl gel electrodes on channel 2. d Comparison of signal-to-noise ratio of ECG signals detected by different electrodes. The gray bar chart and the red bar chart are the SNRs detected by SET on channel 1 and channel 2 respectively. The green bar chart is the SNR detected by the commercial Ag/AgCl gel electrodes on channel 2. Bar height, mean; error bars, s.d.; n = 5 independent samples. e Fluorescent images of cells cultured in the incubation medium with the control sample and PU-SET. Bar height, mean; error bars, s.d.; n = 6 independent samples. f Absorption at 450 nm in the CCK8 assay of different incubation groups after 1, 2, and 3 days of incubation. g Comparing the pictures of skin after different electrodes have been applied for a period of time. h Comparison of ECG signals detected by PU-SET after 1, 3, and 5 days of wearing. i Comparison of ECG signal-to-noise ratio after 1, 3, and 5 days of wearing. Bar height, mean; error bars, s.d.; The standard deviation is based on 3 repeated experiments. j ECG signals detected by PU-SET in compressed and stretched states. k ECG signals in different human states detected by PU-SET. The gray, green, and dark yellow curves are ECG signals in the relaxing state, in the sleeping state and in the post-exercise state respectively. l Fourier transform spectrogram of ECG signal in different human states. The gray, green, and dark yellow curves are the amplitudes of ECG signals in the relaxing state, in the sleeping state and in the post-exercise state respectively.