Identification and quantitation of choline glycerophospholipids that contain aldehyde residues by fluorometric...

A high-performance liquid chromatographic method was established for the fractionation of oxidized choline glycerophospholipids (CGPs) that contain aldehyde residues, after their derivatization with a fluorescent reagent 4-(N,N-dimethylaminosulfonyl)-7-hydrazino-2,1,3-benzoxadiazole (DBD-H). DBD-H efficiently reacted with the aldehyde residues of phospholipids at room temperature. Fluorescent derivatives of aldehydic phospholipids were well separated into species that contained aldehyde groups at different sites. The relationship between the amount of each derivative and the signal was linear over a wide range and amounts as low as several picomoles of aldehydic CGP could be detected. This method is applicable to the quantitation of aldehydic phospholipids in peroxidized membranes of red blood cells. In the present study, formation of aldehydic choline glycerophospholipids was demonstrated for the first time in peroxidized red blood cell membranes and the compounds were quantitated.