Chemiluminescence determination of captopril based on a Rhodamine B sensitized cerium(IV) method

A new Chemiluminescence method for the determination of captopril is described. The method is based on the Chemiluminescence reaction of captopril with cerium(IV) in sulphuric acid medium. Rhodamine B is suggested as a fluorescing compound for the energy-transferred excitation. This sensitized-type of Chemiluminescence emission allows quantitation of captopril concentrations in the 0.1–6.0 μM range with a detection limit of 0.037 μM original concentration. The experimental conditions for the reaction are optimized, the possible reaction mechanism is discussed and a direct application on a commercial drug formulation is given.