Continuous single electrode voltage-clamp (cSEVC) is an electrophysiological patch-clamping method to pass a membrane voltage into a cell and measure the change in current as the voltage steps. In cSEVC, the same electrode is used simultaneously for voltage recording and for current passing. The cSEVC circuit is illustrated as a voltage source (V_cmd) in series with the effective access resistance (R_a.eff) and the membrane (R_m, C_m). The cSEVC circuit ensures that the pipette potential (V_p) is equal to V_cmd.

After V_cmdsteps to V₁, a stead-state current (I_m) flows in the circuit. The membrane potential is equal to V_cmd- I_mR_a,eff. After the step change in the command potential, I_mand V_msettle exponentially to their steady state values with the time constant τ. In general, R_m>> R_a,eff, a good approximation is τ ≈ R_a,effC_m.

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• Axon Instruments patch-clamp products

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