高效液相色谱-荧光检测法测定脂肽

Highly sensitive determination of lipopeptide using HPLC-FLD

脂肽(表面活性素)在酸性水溶液中水解出的亮氨酸与丹磺酰氯反应而被标记,再用高效液相色谱—荧光检测法对标记后的亮氨酸进行检测。结果表明,在60℃反应30 min条件下,亮氨酸能被丹磺酰氯很好地标记。被标记后的亮氨酸色谱积分面积或峰高与亮氨酸及表面活性素的含量具有良好的线性关系,线性相关系数大于0.99。亮氨酸和表面活性素检出限分别为1.4μmol/L和2.2μmol/L。表面活性素的平均回收率为94.6%。方法可应用于微量脂肽的定量测定。

The quantitative determination of lipopeptide with high sensitivity is important for the application of lipopeptide. An HPLC-FLD method was developed to quantify trace lipopeptide. Lipopeptide （surfactin） was hydrolyzed in an acid solution to release leucine, then the leucine was reacted with dansyl chloride. The dansylated leucine was detected by HPLC-FLD for a quantitative determination. The results showed that the leucine could be labeled well with dansyl chloride at 60℃ for 30 min. The relationship of integration area of dansylated leucine with surfactin or with leucine showed good linearity with the linear correlation coefficients above 0. 99. The limits of detection for leucine and surfactin were 1.4 μmol/L and 2.2 μmol/L, respectively. The surfactin average recovery was 94.6%. This new approach can be applied in quantitative determination of trace lipopeptide.