THE REACTIONS OF OSMIUM TETROXIDE WITH LIPIDS AND OTHER COMPOUNDS

Abstract

To clarify the mechanism of the reactions underlying the fixation of tissue lipids with osmium tetroxide, experiments were undertaken in which various unsaturated compounds were allowed to react with osmium tetroxide. Lecithin was taken as a lipid representative of the polar lipids contained in myelin and cell membranes. Other compounds examined were 1-decene, 1-octadecene, oleic acid, methyl oleate, and glycerol trioleate. Each compound was brought together with osmium tetroxide in an inert solvent (carbon tetrachloride and acetic acid respectively). Spectro-photometric analysis by the method of continuous variations showed, that the stoichiometry of the reaction between these compounds and osmium tetroxide is determined by the number of double bonds in the molecule. The nature of the reaction products remains uncertain. The absorption spectrum of the reaction product of lecithin in carbon tetrachloride has characteristics which indicate that in the reaction with osmium tetroxide the lecithin polar group is involved.