DETERMINATION OF SULFONAMIDES IN HUMAN URINE BY AZO-DYE PRECOLUMN DERIVATIZATION AND MICELLAR LIQUID-CHROMATOGRAPHY

A high-performance liquid chromatographic method for the determination of sulphonamides in urine is reported. The drugs (sulphadiazine, sulp haguanidine, sulphamethizole, sulphamethoxazole, and sulphathiazole) w ere diazotized with nitrite and coupled with N-(1-naphthyl)ethylenedia mine dihydrochloride in a sodium dodecyl sulphate (SDS) micellar mediu m. Separation of the sulphonamide azo dyes was performed on a C-18 col umn with a 0.05 M SDS-2.4% pentanol mobile phase, which permitted the direct injection of the urine samples. The limits of detection were in the 0.1-0.3 mu g/ml range.