Abstract
The reduction rate of nitro-blue tetrazolium by superoxide anion radicals during the autoxidation of hydroxylamine (20μM) was inhibited by 67% in the presence of 5μM Cu2+. However, upon the addition of a cationic micelle of hexadecyltrimethylammonium bromide or a nonionic micelle of polyoxyethylene dodecyl ether, the reduction rate markedly increased with an increase of the concentration of Cu2+. The coexistence of 10μM Cu2+ and 5mM cationic or nonionic micelle accelerated this reaction about 50- or 75-fold, respectively, al-though the absence of Cu2+ accelerated the reaction rate only about 8.0- or 6.0-fold, respectively. On the other hand, the generation rate of nitrite during the autoxidation of hydroxylamine was increased by the addition of Cu2+ and decreased by the addition of the micelles. The co-existence effect of Cu2+ and micelles was not observed in the case of nitrite formation reaction. The microenvironmental effects on these reactions were discussed.
