Multichannel Systems Roboocyte2 Manual - Manual (Page 59)

Manual Mode
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The example "TMC test" is composed of three columns starting with a step from 0 mV to -100 mV
and back to 0 mV. to vary the number of columns, please use the buttons "Add Column" and
"Remove Column". The duration for each step is 10 ms. There are 11 repeats with an increment
of 20 mV, which ends up in a final step to +100 mV. The relevant segment for the voltage versus
which the current will be plotted can be chosen with the check box "Rel.Volt". If the single
voltage steps should be executed with a (non-recorded) waiting time in between the function
"Wait Time between Sweeps" can be used. The potential during the wait time between
sweeps can be chosen with the "Potential for Wait Time" function. The values in the boxes for
"Baseline" and "ROI" (Region Of Interest) define the left and right boundaries for determination
of baseline and current, respectively. Choosing the correct boundaries for the baseline current
calculation is important for the correct calculation of leak-subtracted current if leak subtraction
is enabled.
P/N Leak Subtraction
If you enable the "Leak Subtraction" check box, the parameters for defining the P/N leak
subtraction will be accessible and leak subtraction will be performed when the IV recording is
executed. The leak subtraction procedure follows the known standards for P/N leak subtraction.
You can choose between 2 and 4 leak pulses, the "Leak Holding" potential from which the leak
pulses are started and whether the polarity "Type" is "Standard", "Reversed" or "Alternate".
Amplifier Control Parameters
The built-in digital amplifier of the Roboocyte uses a PI control loop feedback mechanism, where
"P" stands for "Proportional" and "I" for "Integral". Units for P and I are nA and mV and 1/s
respectively. Generally spoken, the proportional gain value determines the speed of voltage-
clamp, whereas the integral parameter determines how fast the remaining voltage-error is
compensated. Please refer to chapter "TEVC Recording Background" for details.
Click the button "Save and Accept" under the IV protocol display to save the present IV protocol
and to start the execution of the protocol. Click "Cancel" to stop it.