超高效液相色谱同时测定不同饮料中咖啡因含量

Content of caffeine in different beverages determined simultaneously by ultra-high performance liquid chromatography

目的建立一种能同时测定不同类型饮料中咖啡因含量的超高效液相色谱(ultra-high performance liquid chromatography,UPLC)方法。方法采用Waters H-class超高效液相色谱进行测定,Aquity C18(Ф2.1 mm×100 mm,1.7μm)色谱柱,流动相为甲醇水(24∶76),流速为0.35 ml/min,检测波长为272 nm,柱温为25℃。结果1~200μg/ml浓度范围内各组分峰面积与相应浓度呈良好的线性关系,相关系数r=0.9999,可乐饮料回收率为97.8%~100.3%,茶饮料回收率为94.9%~116.7%,咖啡饮料回收率为97.3%~100.2%,同时测定3种类型饮料的方法精密度RSD为0.02%~0.15%(n=6)。结论超高效液相色谱高效准确,具有较高的准确度和精密度,适合同时检测不同类型饮料中咖啡因的含量。

Objective To test the method for ultra-high performance liquid chromatography(UPLC)simultaneously determining the caffeine in different categories of beverages.Methods Waters H-class UPLC was used to determine Aquity C18(Ф2.1 mm×100 mm,1.7μm)chromatographic column,mobile phase in methanol water(24∶76),flow rate at 0.35 ml/min,detection wavelength at 272 nm,and column temperature at 25℃.Results Satisfactory linear relation was found between the peak area and concentration in 1-200μg/ml concentration within the scope of components,and the results showed that the correlation coefficient was 0.9999,recovery rate of cola beverages ranged from 97.8%to 100.3%,recovery rate of tea beverages scoped from 94.9%to 116.7%,recovery rate of coffee drinks ranged from 97.3%to 100.2%,and RSD of degree of precision of determination on three kinds of drinks was within 0.02%-0.15%(n=6).Conclusion UPLC is efficient and accurate,delivers high accuracy and precision,and is applicable for simultaneously determining the caffeine in different categories of beverages.