Measurement of 4,5-dioxovaleric acid by high-performance liquid chromatography and fluorescence detection

In this work we describe a sensitive method for the detection of 4,5-dioxov aleric acid (DOVA). 4,5-Dioxovaleric acid is derivatized with 3,3-diaminona phthalene to form 3-(benzoquinoxalinyl-2)propionic acid (BZQ), a product wi th favorable UV absorbance and fluorescence properties. The high-performanc e liquid chromatographic method with UV absorbance and fluorescence detecti on is simple and its detection limit is approximately 100 fmol. This method was used to detect 3,5-dioxovaleric acid formation during metal-catalyzed 5-aminolevulinic acid (ALA) oxidation. Iron and ferritin were active in the formation of 4,5-dioxovaleric acid in the presence of 5-aminolevulinic aci d. In addition, HPLC-MS-MS assay was used to characterize BZQ. The determin ation of 4,5-dioxovaleric acid is of great interest for the study of the me chanism of the metal-catalyzed damage of biomolecules by 5-aminolevulinic a cid. This reaction may play a role in carcinogenesis after lead intoxicatio n. The high frequency of liver cancer in acute intermittent porphyria patie nts may also be due to this reaction. (C) 1999 Elsevier Science B.V. All ri ghts reserved.