PITC柱前衍生反相高效液相色谱法测定维生素功能饮料中L-赖氨酸和牛磺酸的含量

建立反相高效液相色谱法检测维生素功能饮料中L-赖氨酸和牛磺酸的含量的分析方法。维生素功能性饮料中的L-赖氨酸和牛磺酸通过苯异硫氰酸酯(PITC)柱前衍生,生成有紫外响应的氨基酸衍生物苯胺基硫甲酰氨基酸(PTC-氨基酸),PTC-氨基酸经RP-HPLC梯度洗脱后检测维生素功能饮料中L-赖氨酸盐酸盐和牛磺酸的含量。使用ZORBAX SB-C18色谱柱(4.6×150mm 5-Micron),流动相A为0.1mol/L的乙酸钠溶液,流动相B为乙腈;流速为1.0mL/min;检测波长为254nm;柱温27℃;进样量20μL。牛磺酸和L-赖氨酸在线性范围内相关系数r0.999,回收率大于97.6,日内RSD分别为0.54%和0.46%(n=6)。结果表明本方法操作性强、灵敏度高,适用于维生素功能饮料中牛磺酸和L-赖氨酸的检测。

Simultaneous Determination of Taurine and L-lysine in Vitamin Functional Drinks by RP-HPLC Pre-column Derivatization

A sensitive RP-HPLC method was established for the simultaneous determination of taufine and L-lysine in vitamin functional drinks. Taurine and L-lysine in vitamin functional drinks were pre-column derivatized with othiocyanate （PITC）, generating amino acid derivatives with UV response called formyl aniline sulfur amino acids （PTC-amino acids ）, then the PTC-amino acids were simultaneously determined by RP-HPLC gradient elution. A ZORBAX SB-C18 chromatographic column （4.6x150mm, 5-Micron） was used. The mobile phase A was 0.1mol/L sodium acetate, and the mobile phase B was acetonitrile. The flow rate was lmg/mL, and the wavelength for determination was 254nm. The column temperature was 27℃ and the injection volume was 20μL. Within the linear range, the correlation coefficients of taurine and L-lysine were more than 0.999, the recovery was more than 97.6, and the intra-day RSD were 0.54% and 0.46% （n=6）, respectively. The results showed that the method, simple and highly sensitive, was suitable for the determination of taurine and L-lysine in vitamin functional drinks.