Determination of taurine in biological samples by reversed-phase liquid chromatography with precolumn derivatization with dinitrofluorobenzene

A rapid and sensitive method for the determination of taurine in human milk and urine by reversed-phase liquid chromatography (LC) has been developed. It involves precolumn derivatization with dinitrofluorobenzene in NaHCO3 buffer (pH 9.0), catalysed by dimethyl sulphoxide, separation by LC on a μBondapak Phenyl column at 40°C with acetonitrile-water (1:1) and 0.01 mol l−1 phosphate buffer (pH 5.5) as mobile phase and UV absorbance detection at 360 nm. The peak area is proportional to the concentration of taurine in the range 10–80 μg ml−1, the correlation coefficient being 0.9997. The detection limit in standard solutions is 0.01 μg ml−1 (signal-to-noise ratio = 3). The relative standard deviation (n = 6) of retention time and peak area are 0.45% and 2.29%, respectively. The average recovery for human milk and urine are 95.8% and 101.0%, respectively.