Liquid chromatographic determination of aniline in table-top sweeteners based on pre-column derivatization with 1,2-naphthoquinone-4-sulfonate

A liquid chromatographic method for the determination of aniline in cyclama te sweeteners based on a pre-column derivatization with 1,2-naphthoquinone- 4-sulfonate (NQS) is proposed. Aniline traces were extracted from the cycla mate samples using dichloromethane. After solvent evaporation, the dry resi due was derivatized with NQS at pH 9.5 and 85 degrees C for I min. The anil ine derivative, which was extracted from the reacting mixture, was redissol ved in the eluent solution and injected into the chromatographic system. Th e separation of aniline derivative from other amine impurities was carried out in a C-18 column using a 2% acetic acid-methanol (40:60, v/v) mobile ph ase. Results from the analysis of aniline in the sweetener samples with the proposed method were compared with those from the standard method. A good concordance between the two methods was observed. (C) 1999 Elsevier Science BN. All rights reserved.