Quantitative gas chromatographic-mass spectrometric assay of five sulfonamide residues in animal tissue.

A gas chromatographic-mass spectrometric procedure using isotopically labeled internal standards and the technique of selective-ion monitoring was used to assay sulfamethazine, sulfadimethoxine, sulfabromethazine, sulfathiazole, and sulfaquinoxaline in liver and muscle tissue of swine, poultry, and cattle. The data presented clearly demonstrate the applicability of this procedure for confirmation of sulfonamide residues in animal tissue.