反相高效液相色谱-柱前衍生化法测定大青叶中氨基酸的含量

目的:建立以反相高效液相色谱法测定大青叶中精氨酸和脯氨酸含量的方法。方法:采用2,4—二硝基氟苯柱前衍生化,将氨基酸在碱性条件下衍生后直接进样测定;色谱柱为KromasilC18,流动相为醋酸钠缓冲溶液(pH=6.4)-乙腈(850∶150),检测波长为360nm,外标法计算含量。结果:精氨酸和脯氨酸进样量分别在0.627μg～5.016μg(r=0.9996)、0.874μg～7.000μg(r=0.9995)范围内线性关系良好;平均回收率均为98.2%(RSD=2.3%、2.2%)。结论:本法简便、准确、可靠,适用于大青叶中氨基酸的含量测定。

Content Determination of Amino Acids in Folium Isatidis by RP - HPLC Precolumn Derivatization Method

OBJECTIVE:To establish a RP-HPLC precolumn derivatization method for the content determination of argi-nine(Arg)and proline(Pro)in Folium Isatidis.METHOD:2,4-dinitro-fluorobenzene was undergone precolumn derivatization and the amino acids was determined directly under alkaline condition with Kromasil C 18 as chromatographic column,the mobile phase was composed of sodium acetate buffer solution(pH=6.4)-acetonitrile(850∶150)with detection wavelength at360nm,the content was calculated by external reference method.RESULTS:The linear ranges for Arg and Pro were0.627μg～5.016μg(r=0.9996)and0.874μg～7.000μg(r=0.9995),respectively.The average recovery was98.2%with RSD at2.3%and2.2%,respectively.CONCLUSION:The method is simple,accurate and reliable,and suitable for the assaying of amino acids in Folium Isatidis.