Checking silver, platinum, and gold electrodes

Methods for testing the condition of metal electrodes are presented.Pt and Au electrodes can be tested with the Metrohm ready-to-use 6.2306.020 Redox standard. Alternatively, the potential of quinhydrone saturated in buffer can be measured and compared to theoretical values. All electrodes can be checked by titration. For Ag electrodes, a determination of hydrochloric acid with silver nitrate is performed, for Pt and Au electrodes an iodine solution is titrated with sodium thiosulfate. An appropriate criterion is the titration duration, which should not exceed 150s for the Ag- and Pt-DET titration and 160s for the Au-MET titration.