In metrology there is a rule. One measurement means nothing.

The solution is to incubate (more or less large) series of electrodes, not single electrodes. For each series calculate an average value and a standard deviation. By further calculating the uncertainty, you may claim a level of confidence in your results.

This would be true for scientific evaluations, of course. In this cause we want to make an application. It is to expensive and not feasible to make 100 measurements for one patient at least with our protocol.

see attached

Giving single electrodes a calibration data set is no problem. This can be achieved with a bar code or QR code.

The questions is how do you correct a measurement according to the background measurement. Can you just subtract the Bode plots?

I think, you can't, because not all the contributions are additive.

Dear Lutz

This statement of yours, ... It is to expensive and not feasible to make 100 measurements for one patient at least with our protocol....  it seems to show that the problem is precisely focused on the production of the electrodes. That is, this process is not being controlled at 100 %, so I suggest work harder to improve this production process. Especially if it is very expensive and to be applied in patients. In the latter case, when demanding to obtain reliable results.

Regards

This statement of yours, ... It is to expensive and not feasible to make 100 measurements for one patient at least with our protocol....  it seems to show that the problem is precisely focused on the production of the electrodes. That is, this process is not being controlled at 100 %, so I suggest work harder to improve this production process. Especially if it is very expensive and to be applied in patients. In the latter case, when demanding to obtain reliable results.

Regards