DETERMINATION OF SULFONAMIDES IN FOODS BY LIQUID-CHROMATOGRAPHY WITH POSTCOLUMN FLUORESCENCE DERIVATIZATION

A postcolumn fluorimetric derivatization procedure for the detection a nd simultaneous determination of several sulphonamides using liquid ch romatography was developed. The derivatization method involves the rea ction of the sulpha drugs with o-phthaldialdehyde and beta-mercaptoeth anol. The chromatographic elution programme consisted of an initial is ocratic step with acetonitrile-water (3:97) for 5 min followed by a li near gradient up to a 40:60 mixture over 15 min. The proposed method w as applied to routine quality control analysis to ensure the absence o f sulphonamides in foods, resulting in an overall mean recovery of 95% (n = 45) at fortification levels of 0.04, 0.1 and 0.5 mu g/ml.