Simultaneous screening of homotaurine and taurine in marine macro-algae using liquid chromatography-fluorescence detection

Simultaneous analysis of homotaurine and its homologous, taurine, is a highly challenging issue, especially in matrices they exist simultaneously. A simple precolumn derivatization procedure combined with high-performance liquid chromatography-fluorescence detection was developed for simultaneous determination of homotaurine and taurine in marine macro-algae. The analytes were derivated with o-phthalaldehyde at an ambient temperature and alkaline medium. Calibration curves were linear in the ranges of 50-2500 A mu g L-1 for homotaurine and 100-2500 A mu g L-1 for taurine with the coefficients of determination higher than 0.998. Limits of detection of homotaurine and taurine were 15 and 30 A mu g L-1, respectively. Intraday (n = 6) and inter-day (n = 4) precisions of the method were satisfactory with relative standard deviations less than 6.0%. Good recoveries (> 94%) were acquired by the method for extraction of homotaurine and taurine from algae matrices. Liquid chromatography-mass spectrometry was also used to confirm detection of the analytes in algae samples. The data suggest that the method was successfully applied to simultaneous determination of homotaurine and taurine in algae samples.