Zacytuj

Fig. 1

Methods, a) Applied voltage stimuli that were used for the recordings with silver/silver chloride electrodes in sodium chloride solution. The recordings with 0.4 V and 0.8 V amplitude were done ones and also with an additional frequency of 0.05 Hz. b) Schematic of the used measurement instrumentation. This three-electrode configuration [13], with “CC” as the current-carrying electrode and “Ref” as the reference electrode enables monopolar recordings under the measurement (“M”) electrode. c) Test setup with the silver/silver chloride electrodes. The test setup with the stainless steel and aluminum electrodes was equivalent. The M electrode was placed on one side of the plastic bottle, the CC and the Ref electrodes were placed on the opposite side. The distance between both sides was approximately 6 cm. The wires of the electrodes were taped against the walls of the plastic bottle to keep the electrodes more or less in position.
Methods, a) Applied voltage stimuli that were used for the recordings with silver/silver chloride electrodes in sodium chloride solution. The recordings with 0.4 V and 0.8 V amplitude were done ones and also with an additional frequency of 0.05 Hz. b) Schematic of the used measurement instrumentation. This three-electrode configuration [13], with “CC” as the current-carrying electrode and “Ref” as the reference electrode enables monopolar recordings under the measurement (“M”) electrode. c) Test setup with the silver/silver chloride electrodes. The test setup with the stainless steel and aluminum electrodes was equivalent. The M electrode was placed on one side of the plastic bottle, the CC and the Ref electrodes were placed on the opposite side. The distance between both sides was approximately 6 cm. The wires of the electrodes were taped against the walls of the plastic bottle to keep the electrodes more or less in position.

Fig. 2

Voltage current plots recorded with the silver/silver chloride electrodes, always shown for the second period of each measurement. The arrows indicate the orientation of the pinched hysteresis loops. If not stated otherwise, the results from the recordings with applied triangular voltage are shown. Subplots a) to d) represent the recordings in the sodium chloride solution (3 g/l if not stated otherwise), and e) to f) are recordings of human skin from one test person at the forehead. a) Results from the recordings with 0.1 V amplitude and frequency of 0.01 Hz shown for two different solution concentrations (results from the 3 g/l sodium chloride solution are presented in dark blue and from the 1.8 g/l sodium chloride solution are presented in light blue). b) Results from the recordings with 0.2 V amplitude shown for two different frequencies. c) Results from the recordings with 0.4 V amplitude and f=0.01 Hz and two different voltage waveforms. d) Results from the recordings with 0.8 V amplitude shown for two different frequencies. e) Results from the recordings on human skin with 0.8 V amplitude and f=0.01 Hz and two different voltage waveforms. f) Results from the recordings on human skin with triangular waveform and 0.8 V amplitude and f=0.1 Hz and 1.5 V amplitude and f=0.05 Hz.
Voltage current plots recorded with the silver/silver chloride electrodes, always shown for the second period of each measurement. The arrows indicate the orientation of the pinched hysteresis loops. If not stated otherwise, the results from the recordings with applied triangular voltage are shown. Subplots a) to d) represent the recordings in the sodium chloride solution (3 g/l if not stated otherwise), and e) to f) are recordings of human skin from one test person at the forehead. a) Results from the recordings with 0.1 V amplitude and frequency of 0.01 Hz shown for two different solution concentrations (results from the 3 g/l sodium chloride solution are presented in dark blue and from the 1.8 g/l sodium chloride solution are presented in light blue). b) Results from the recordings with 0.2 V amplitude shown for two different frequencies. c) Results from the recordings with 0.4 V amplitude and f=0.01 Hz and two different voltage waveforms. d) Results from the recordings with 0.8 V amplitude shown for two different frequencies. e) Results from the recordings on human skin with 0.8 V amplitude and f=0.01 Hz and two different voltage waveforms. f) Results from the recordings on human skin with triangular waveform and 0.8 V amplitude and f=0.1 Hz and 1.5 V amplitude and f=0.05 Hz.

Fig. 3

Results from the second experiment, recorded with the silver/silver chloride electrodes, A1, A2 and A3 reflect the measurements in the 3 g/L NaCl solution (first, second, and third time, respectively) and the B1 and B2 reflect the measurement results in 1.8 g/L NaCl solution. a) Non-linear electrical measurements with DC voltage pulses. Measured current, i, and applied voltage, v, plotted over time. b) Small-signal conductance measurements after each DC pulse series. The time is related to the end of the last pulse of the corresponding DC pulse series.
Results from the second experiment, recorded with the silver/silver chloride electrodes, A1, A2 and A3 reflect the measurements in the 3 g/L NaCl solution (first, second, and third time, respectively) and the B1 and B2 reflect the measurement results in 1.8 g/L NaCl solution. a) Non-linear electrical measurements with DC voltage pulses. Measured current, i, and applied voltage, v, plotted over time. b) Small-signal conductance measurements after each DC pulse series. The time is related to the end of the last pulse of the corresponding DC pulse series.

Fig. S1

Voltage current plots recorded with the stainless steel electrodes, always shown for the second period of each measurement and the two different solutions (results from the 3 g/l sodium chloride solution are presented in dark blue and results from the 9 g/l sodium chloride solution are presented in light blue). a) Applied triangular voltage with 0.4 V amplitude and frequency of 0.01 Hz. b) Repeated measurement with the same stimulus as in a) carried out one day later. c) Same stimulus as in a) but with an additional DC offset of 0.2 V. d) Applied sinusoidal voltage with 0.4 V amplitude and frequency of 0.01 Hz. e) Applied triangular waveform with a frequency of 0.1 Hz and an amplitude of 0.4 V. f) Applied triangular voltage with 0.2 V amplitude and a frequency of 0.01 Hz. g) Applied triangular voltage with 0.8 V amplitude and a frequency of 0.01 Hz. h) Result from a recording on human skin at the forehead of one test subject with sinusoidal voltage with an amplitude of 2 V and a frequency of 0.05 Hz.
Voltage current plots recorded with the stainless steel electrodes, always shown for the second period of each measurement and the two different solutions (results from the 3 g/l sodium chloride solution are presented in dark blue and results from the 9 g/l sodium chloride solution are presented in light blue). a) Applied triangular voltage with 0.4 V amplitude and frequency of 0.01 Hz. b) Repeated measurement with the same stimulus as in a) carried out one day later. c) Same stimulus as in a) but with an additional DC offset of 0.2 V. d) Applied sinusoidal voltage with 0.4 V amplitude and frequency of 0.01 Hz. e) Applied triangular waveform with a frequency of 0.1 Hz and an amplitude of 0.4 V. f) Applied triangular voltage with 0.2 V amplitude and a frequency of 0.01 Hz. g) Applied triangular voltage with 0.8 V amplitude and a frequency of 0.01 Hz. h) Result from a recording on human skin at the forehead of one test subject with sinusoidal voltage with an amplitude of 2 V and a frequency of 0.05 Hz.

Fig. S2

Results from the second experiment, recorded with the stainless steel electrodes, A1, A2 reflect the measurements in the 3 g/L NaCL solution (first and second time, respectively). a) Non-linear electrical measurements with DC voltage pulses. Measured current, i, and applied voltage, v, plotted over time. b) Small-signal conductance measurements after each DC pulse series. The time is related to the end of the last pulse of the corresponding DC pulse series.
Results from the second experiment, recorded with the stainless steel electrodes, A1, A2 reflect the measurements in the 3 g/L NaCL solution (first and second time, respectively). a) Non-linear electrical measurements with DC voltage pulses. Measured current, i, and applied voltage, v, plotted over time. b) Small-signal conductance measurements after each DC pulse series. The time is related to the end of the last pulse of the corresponding DC pulse series.

Fig. S3

Voltage current plots recorded with the aluminum electrodes, always shown for the second period of each measurement and the two different solutions (results from the 3 g/l sodium chloride solution are presented in dark blue and results from the 9 g/l sodium chloride solution are presented in light blue). a) Applied triangular voltage with 0.4 V amplitude and frequency of 0.01 Hz. b) Repeated measurement with the same stimulus as in a) carried out one day later. c) Same stimulus as in a) but with an additional DC offset of 0.2 V. d) Applied sinusoidal voltage with 0.4 V amplitude and frequency of 0.01 Hz. e) Applied triangular waveform with a frequency of 0.1 Hz and an amplitude of 0.4 V. f) Applied triangular voltage with 0.2 V amplitude and a frequency of 0.01 Hz. g) Applied triangular voltage with 0.8 V amplitude and a frequency of 0.01 Hz.
Voltage current plots recorded with the aluminum electrodes, always shown for the second period of each measurement and the two different solutions (results from the 3 g/l sodium chloride solution are presented in dark blue and results from the 9 g/l sodium chloride solution are presented in light blue). a) Applied triangular voltage with 0.4 V amplitude and frequency of 0.01 Hz. b) Repeated measurement with the same stimulus as in a) carried out one day later. c) Same stimulus as in a) but with an additional DC offset of 0.2 V. d) Applied sinusoidal voltage with 0.4 V amplitude and frequency of 0.01 Hz. e) Applied triangular waveform with a frequency of 0.1 Hz and an amplitude of 0.4 V. f) Applied triangular voltage with 0.2 V amplitude and a frequency of 0.01 Hz. g) Applied triangular voltage with 0.8 V amplitude and a frequency of 0.01 Hz.

Fig. S4

Results from the experiment applied DC pulses, recorded with the aluminum electrodes, A1, A2 reflect the measurements in the 3 g/L NaCL solution (first and second time, respectively) and B1 represents the result with the 9 g/L NaCl Solution. a) Non-linear measurements with DC voltage pulses. Measured current, i, and applied voltage, v, plotted over time. b) Small-signal conductance measurements after each DC pulse series. The time is related to the end of the last pulse of the corresponding DC pulse series.
Results from the experiment applied DC pulses, recorded with the aluminum electrodes, A1, A2 reflect the measurements in the 3 g/L NaCL solution (first and second time, respectively) and B1 represents the result with the 9 g/L NaCl Solution. a) Non-linear measurements with DC voltage pulses. Measured current, i, and applied voltage, v, plotted over time. b) Small-signal conductance measurements after each DC pulse series. The time is related to the end of the last pulse of the corresponding DC pulse series.