It depends on what you want to observe. Both I-clamp (for potential measurement) and V-clamp (for current measurement) have their own separate purposes. However, voltage clamp has been sometimes criticised for the space clamp problem, i.e., many times the potential you are applying is not maintained all over the cell. However, if the dimensions of the cells you are concerned about are small, then it is not a problem.

I agree with Swagata, but in your case, I guess it depends on what you want to control in order to attract the molecules through your nanopores.  In the simplest terms: in V-clamp mode, you are trying to clamp the voltage (or potential) at a particular set-point and monitoring the current passing through your pipette (or nanopores?) in order to do that.  Switching to I-clamp will allow you to clamp the current at a particular set-point and you will now be monitoring the potential change across your pipette (or nanopores?).  Depending on how your experiment is designed and what you are ultimately interested in measuring will dictate which mode you need to use.

Hi Abeer,

In voltage-clamp mode you control (or clamp) the membrane potential at any level desired and monitor the current flow. In current clamp, you clamp the current instead of the voltage, and monitor changes in membrane potential. The way your amplifier does that is more subtle but you get the sense. If you want to know more there is a RG thread discussing the difference between V-clamp and I-clamp modes https://www.researchgate.net/post/How_exactly_does_current_and_voltage_clamping_work

Hope this helps. Norbert

see

https://www.neuron.yale.edu/phpBB/viewtopic.php?p=349&sid=b2f27500aa320506c89b1d52369683d9#p349