Abstract
An electrochemiluminescence method was developed for determination of sub-nmol hydrogen peroxide in aqueous solution. Luminol was electrochemically oxidized, then reacted with hydrogen peroxide; it emitted light of the maximum wavelength of 436nm with a half-life of less than 0.2s from the electrode surface. In flow injection analysis a carrier solution (phosphate buffer, pH 7-9) containing 17μM luminol was delivered at the flow rate of 0.5ml/min. The luminescence was detected by a photon counter in a spiral cell under the applied potential of 0.7V vs. SCE. A straight line calibration plot was obtained with good reproducibility [RSD 1.6% (n=5)] in the concentration range of 0.066 to 0.6nmol.