[Determination of taurine in Lycium barbarum L. by high performance liquid chromatography with OPA-urea pre-column...

Dried Lycium Barbarum L. is pretreated simply through shivering, homogenizing and centrifuging, and then the extract is passed through a cation-exchange column to exclude the interference of other amino acids. The effluent is derivatized prior to high performance liquid chromatographic separation on a Zorbax-C8 column. The derivatization reagents consist of A and B (1:9, V/V). A is 4% OPA solution in methanol (W/V); B is urea:sodium phosphate buffer (pH 6.8) = 1:3 (W/V). The mobile phase is methanol:0.01 mol/L sodium acetate (pH 6.8) = 35:65 (V/V). The ultraviolet-visible detector is at 330 nm. 0.1-1.0 mmol/L taurine can be determined quantitatively. The recovery is 100.31% +/- 1.98%. Coefficient of variation is 1.94%.