Determination of plasmalogens after treating with a 2,4-dinitrophenylhydrazine-phosphoric acid reagent

A method for the quantitative determination of plasmalogens is described. Glycerophosphatide fractions from animal and plant sources were treated with a 2,4-dinitrophenylhydrazine-phosphoric acid reagent. The plasmalogen content was estimated by two different procedures after a single treatment with reagent: a) by determining the phosphorus content of diacyl phospholipid and (2-acyl) lysophospholipid separated by thin-layer chromatography, b) by spectrophotometric determination of the 2,4-dinitrophenylhydrazones and phosphorus assay of the original untreated sample. The total plasmalogen content of an unfractionated extract may be determined easily by the latter procedure.The method described gives results comparable with those from the p-nitrophenylhydrazine method and iodination procedure. The usefulness of this 2,4-dinitrophenylhydrazine-phosphoric acid treatment for further structural analyses of plasmalogens is discussed.