SEPARATION AND IDENTIFICATION OF DESFERRIOXAMINE AND ITS IRON CHELATING METABOLITES BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY AND FAST ATOM BOMBARDMENT MASS-SPECTROMETRY - CHOICE OF COMPLEXING AGENT AND APPLICATION TO BIOLOGICAL-FLUIDS

An HPLC-based method capable of separating desfer-rioxamine (DFO) and its iron chelating metabolites from uv-absorbing species present in biological fluids has been developed. This method relies on the use of nitrilotriacetic acid (NTA) as the complexing agent in the mobile phase, instead of EDTA, previously used in HPLC methods. The use of NTA ensures that iron contamination present in buffers and bound to the column does not interfere with analysis. The disadvantages of using EDTA are discussed. The identity of the iron chelating metabolites of DFO present in the urine of patients with β-thalassemia major has been established using FAB mass spectrometry. The metabolism of DFO, reported in this study, takes place almost exclusively at the N-terminal region of the molecule and is in many respects similar to the degradation of the amino acid lysine. In addition, a metabolite which corresponds to N-hydroxylation of the terminal amino group has been identified. © 1990.