DETERMINATION OF 5-AMINOLEVULINIC ACID IN BLOOD-PLASMA, TISSUES AND CELL-CULTURES BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH ELECTROCHEMICAL DETECTION

A simple and sensitive method for determining 5-aminolevulinic acid (A LA) in biological samples is described. ALA is derivatized with o-phth aldehyde to give a compound with favorable properties for high-perform ance Liquid chromatography with electrochemical detection. The method does not require extensive pretreatment of the samples and its detecti on limit is in the range of 1 pmol/20 mu l injection. This method was applied to the determination of plasma ALA from normal and lead-expose d subjects, where 0.26 +/- 0.08 mu M (n = 30) and 2.6 +/- 0.75 mu M (n = 30), respectively were found. We also determined ALA in rat tissues , namely liver and brain, and the uptake of ALA by cultured fibroblast s and hepatocytes to illustrate the diversified applicability of the m ethod. (C) 1997 Elsevier Science B.V.