DETERMINATION OF TAURINE IN COSMETIC AND PHARMACEUTICAL PREPARATIONS BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH INDUCTIVELY-COUPLED PLASMA-ATOMIC EMISSION-SPECTROMETRY

A method was developed for determination of taurine in cosmetic and pharmaceutical preparations by high performance liquid chromatography (HPLC) with inductively coupled plasma atomic emission spectrometry (ICP-AES), which was used for selective sulfur detection by observing emission intensity at 180.73 nm. HPLC conditions used were: column, CAPCELL PAK NH2 (4.6 mm i.d. X 250 mm); mobile phase, 2 mM ammonium dihydrogen phosphate-ammonium hydroxide buffer (pH 8.0) containing methanol at 20% (v/v) concentration; injection volume, 10 mu l. The cross flow nebulizer performed at 2 times the intensity of the concentric nebulizer. No peak broadening, tailing or distortion were observed in ICP-AES chromatograms in comparison with UV chromatograms. The detection limit was 43 np as taurine or 11 ng as sulfur with an S/N ratio of 3. A linear relationship was observed between peak area and amount of taurine injected in the range of 98 ng similar to 2.9 mu g (25 similar to 750 ng as sulfur). Several cosmetic and pharmaceutical preparations containing 0.1 similar to 5% taurine were analyzed, the values coincided well with the contents described on the label descriptions. Analysis was performed in only 6 min, without any interference. The method showed an excellent reproducability with an R.S.D. of less than 2.2% and also provided a good recovery rate of 95.7 similar to 103.7% for the added standard.