Oxygen Electrodes and Oxygen Optodes
Typically, respirometry instruments use oxygen electrodes to measure the oxygen concentration in the cell suspension. These electrodes need to be calibrated every day and their calibration can drift during the day.
The Iberius system uses an oxygen optode which measures oxygen concentration using a phosphorescent compound which is quenched in the presence of oxygen. The Iberius measures the lifetime of the phosphorescence, which is extremely stable. These optodes maintain their calibration week in, week out.