绿茶中咖啡因含量测定研究

目的]建立绿茶中咖啡因含量测定的方法。方法]采用高效液相色谱法测定绿茶中咖啡因的含量,以C18柱(4.6 mm×250 mm,5μm)为色谱柱,以乙腈-水-冰醋酸-乙二胺四乙酸(15.0∶82.8∶2.0∶0.2)为流动相,流速1.0 ml/min,检测波长278 nm。结果]绿茶中咖啡因在0.64～3.20μg范围内线性关系良好,平均回收率为100.49%(RSD=1.12%)。结论]该方法简便、准确、重现性好,可作为绿茶中咖啡因含量的测定方法。

Study on Determination Method of Caffeine Content in Green Tea

Objective] To establish the method of determining caffeine in green tea by HPLC.Method] HPLC method was adopted to determine caffeine content in green tea.The analytical column was C18(4.6 mm×250 mm,5 μm),the mobile phase consisted of acetonitrile-water-glacial acetic acid-EDTA(15.0∶ 82.8∶ 2.0∶ 0.2),the flow rate was 1.0 ml/min,the detection wavelength was 278 nm.Result] The linear limits of caffeine ranged was 0.64-3.20 μg,the relative recovery was 100.49%(RSD=1.12%).Conclusion] The method is simple and accurate with a good reproducibility,which can be used as an analysis method for determining caffeine in green tea.