Application of 2,4-dinitrofluorobenzene pre-column derivatization to quantitative determination of taurine and its intermediate in beverages and milk samples

With 2,4-dinitrofluorobenzene-acetonitrile pre-column derivatization, taurine and its intermediate (2-aminoethyl hydrogen sulfate) in beverages and milk samples were determined by high-performance liquid chromatography coupled with diode array detection. Chromatographic separation was performed by isocratic reverse phase model with acetonitrile-phosphate solution (pH 7.0) (19: 81, v/v) as the mobile phase on a C₁₈ column. By precipitation protein and filter, the sample could be directly used for precolumn derivatization and detection. Good linearity was observed in a range of 0.4-500 mg/L for all analytes with the correlation coefficients (r²) ≥ 0.9991. Overall recoveries of the two compounds ranged from 82% to 103% with repeatability (RSD) less than 4.6% at three different spiked levels (5 to 200 mg/L, n = 5). The proposed method offered a good alternative for routine analysis due to its simplicity and at the same time reliability.