Extended Data Figure 9: CNT porin conductance in cellular membranes.

a, Schematic of the on-cell patch clamp measurement. b, c, On-cell conductance measurements demonstrate no channel activity (b) and appearance of a small flickering channel (c) in control experiments with HEK293T cells. Holding potentials were −60 mV (b) and +60 mV (c), the time order is from left to right, top to bottom. d, In the presence of CNT porin (0.15% dilution of the stock), large channel activity is detected, holding potential −60 mV. e, Metastable conductance sub-states of 50 pS detected with CNT porin incorporated into the plasma membrane of CHO cell, holding potential −60 mV. f, Mean patch conductance (on cell configuration, 0.15% CNT stock solution in the patch pipette) detected in CHO and HEK293T cells at positive and negative holding potentials. Error bar, s.d.; 4 cells). In ∼70% of HEK293T cells and 95% of CHO cells we did not observe significant dependence of the conductance on the holding potential; only those cells were used for the conductance analysis.