First, the electrolyte was pumped into the cell employing a peristaltic pump (model PP 1-05, Zalimp, Poland), and then the pump was stopped for the DPV measurements. Afterwards, the electrolyte was pumped again to clean the 3DPEC (50 mL/min for 5 min) before the nimesulide concentration was increased for the next test. These tests were carried out in order from lowest to highest nimesulide concentration.