Process and device for emulating a counter-electrode in a monolithically integrated electrochemical analysis system

A method for operation of a sensor array which is monolithically integrated at least one of in and on a substrate in an electrochemical analysis method, wherein the sensor array includes at least three electrodes forming a pixel arrangement, a majority of the at least three electrodes being designed as a biosensor arrangements for detection of biomolecules, a potentiostat circuit, and includes a switching unit designed such that at least one of the at least three electrodes is selectively connected as a working electrode and the other electrodes of the at least three electrodes are connected as an opposing electrode, and wherein each of the at least three electrodes can be alternatively connected as the working electrode or as the opposing electrodes can be alternatively connected as the working electrode or as the opposing electrode by the switching unit and the opposing electrode is exclusively formed by the other electrodes of the at least three electrodes of the pixel arrangement connected as the opposing electrode, and the at least three electrodes are designed such that sensor events take place at one electrode, connected as the working electrode, of the at least three electrodes in an electrolyte solution when in presence of an electrolytic analyte, the method comprising:

• (a) connecting at least two electrodes, of the at least three electrodes, to the opposing electrode connection of the potentiostat circuit, thus providing the opposing electrode of the sensor array monolithically integrated at least one of in and on the substrate;
• (b) connecting at least one electrode of the at least three electrodes, as a working electrode for detection of the electrolytic analyte;
• (c) connecting, after detection of the electrolytic analyte at the working electrode in (b), at least one of the at least three electrodes as a working electrode for detection of an electrolytic analyte;
• (d) connecting at least one of the at least three electrodes according to (a) as an opposing electrode;
• and
• (e) repeating steps (a) to (d) as often as required;
• wherein, before step (e) the switching unit deactivates an operating circuit of the selected working electrode and connects the selected working electrode to the selected opposing electrode via the potentiostat circuit.