Automated determination of 4,4'-diaminodiphenylsulfone (DDS) and acetyl metabolites (MADDS and DADDS) in milk with the FAST-LC system

Abstract

With the described method it is possible to determinate residues of Dapsone (DDS) and its acetylated metabolites (mono- and diacetyldapsone) in milk. The determination is being carried out with a FAST-LC system (Fully Automated Sample Treatment Liquid Chromatography). The purification is a combination of dialysing the milk against water and absorption of the nonpolar components from the dialysate on the preconcentration column of the LC-system used (RP, 40 microns). With back-flush, the concentrate is being injected into the analytical column (RP-8, 5 microns). The detection is being carried out with the help of a UV-absorbance detector, at a wavelength of 296 mm. The detection limit is approximately 2 micrograms/l (DADDS: 5 micrograms/l). The required amount of the sample is 5 ml. The recovery, reproducibility and linearity for the three components in milk are good.