電化學感測電極及用於檢測待測液之過氧化氫濃度之方法(二)

An electrochemical sensing electrode comprises a conductor and a sensing film that is used for covering said conductor and contains a carboxylic polybenzimidazole(PBI) derivative. This invention also provides a method for detecting the concentration of H2O2 in a tested solution. The method comprises the steps of charging said tested solution into the electrochemical sensor containing above sensing electrode, oxidizing part of the nitrogen atoms of the carboxylic PBI derivative that is contained in the sensing film, applying a constant voltage to the sensor to reduce the oxidized carboxylic PBI derivative, measuring the needed current values, and calculating the concentration of H2O2 in the tested solution according to a current v.s. the concentration of H2O2 plot. The sensing electrode in this invention shows better specificity and sensitivity through using the above sensing electrode to detect H2O2 in the presence of interference substances.