Fig. 6: Nonlinear dynamic analysis of the action potential recording of cardiomyocytes using NWMEA and NPMEA devices.

(a-d) Two-dimensional phase space reconstruction of the action potential recordings of cardiomyocytes using the NWMEA device before and after electroporation. The graphs were reconstructed a before electroporation, b at the moment of electroporation, c 2 min after electroporation, and d 5 min after electroporation. e–h Two-dimensional phase space reconstruction of the action potential recordings of cardiomyocytes using the NPMEA device before and after electroporation. The graphs were reconstructed e before electroporation, f at the moment of electroporation, g 2 min after electroporation, and h 5 min after electroporation. i The short-term shape indices for the NWMEA biodevice immediately after electroporation compared to those before electroporation. j The long-term shape index variations after electroporation compared to those before electroporation for the NWMEA. k The long-term shape index variations after electroporation compared to those immediately after electroporation for the NWMEA. l The short-term shape indices for the NPMEA biodevice immediately after electroporation compared to those before electroporation. m The long-term shape index variations after electroporation compared to those before electroporation for the NPMEA. n The long-term shape index variations after electroporation compared to those immediately after the electroporation NPMEA. In the reconstructed graphs, the contour plots were averaged over 20 s after the selected time points. Solid and transparent lines denote the averages of the contour plots and contour plots for individual action potentials, respectively. n = 6, *p < 0.05, **p < 0.01, and ***p < 0.001 in the unpaired t test