Collect. Czech. Chem. Commun. 1979, 44, 981-985

Study of the reaction of nitrosobenzene with haemoglobine

Václav Holeček, Jan Kopecký and Stanislav Škramovský

Institute of Hygiene and Epidemiology, Department of Labour Hygiene and Occupational Diseases, 100 42 Prague 1


During the reaction of haemoglobine with nitrosobenzene, the latter was determined polarographically. Nitrosobenzene bound by coordination to the divalent Fe atom of haemoglobine was polarographically inactive; it was set free from this complex by oxidation of the iron with ferricyanide and then determined. At a molar ratio of nitrosobenzene to haemoglobine of 4 : 1, at which the molar ratio of iron to nitrosobenzene is 1 : 1, 0.9 mol of nitrosobenzene is bound by coordination to the iron while 0.1 mol is reduced by SH groups to azo- and azoxybenzene. After the SH groups of haemoglobine had been blocked by cyanoethylation or oxidation, nitrosobenzene was bound to iron in a stoichiometric ratio. Accordingly, the conditions for the polarographic determination of nitrosobenzene after oxidative splitting of the complex with haemoglobine are defined.