Formation of singlet oxygen during farmorubicin oxidation

The enhanced generation of singlet oxygen (1O2) during oxidation of farmorubicin in the Co(II)+H2O2 system was studied using chemiluminescent, fluorescent and spectrophotometic techniques. The influence of 1O2-quenchers, catalase, superoxide anion radical image and hydroxyl radical (HOradical dot) scavengers on the light emission was studied. The spectrophotometric determination of 1O2 was based on bleaching of p-nitrosodimethylaniline caused by an intermediate product of the reaction of 1O2 with imidazole, and was followed by monitoring the decrease in optical density at 440 nm.