高效液相色谱法测定五种茶叶中咖啡因含量

目的：采用高效液相色谱法测定了5种茶叶中咖啡因的含量。方法：采用Phenonm enxC18（4.6 mm×250 mm,5μm）反相色谱柱,流动相CH3OH H2O=5.5 4.5,流速1.0（mL·m in^-1）,检测波长为272 nm,柱温为35℃,在所选条件下,样品中待测组分与其它组分分离良好（R〉1.5）,通过重复性实验和加标回收实验,验证了方法的稳定性和可靠性。在本实验范围内各组分的峰面积和浓度之间具有良好的线性关系,r^2=0.999 9,5种茶叶的咖啡因回收率97.48%～107.73%,RSD=2.6%～3.0%。

Determination of CAF in Five Kinds of Tea by High-performance Liquid Chromatography

Objective：To analyze the content of CAF in tea by HPLC.Methods：the study was using a Phenonmenx C18（4.6 mm×250 mm,5 μm） as the reversed phase column,with the mobile phase of methanolwater（5.54.5）,the velocity of flow was 1.0 mL· min^-1,the UV detection wavelength was 272 nm,the column temperature was 35 ℃.Results：Under the selected condition,the aim ingredient in the samples got an ideal resolution with others（the resolution was above 1.5）.In addition,the repetition and sample recovery experiment verify the stability and reliability of the method.The results show that the calibration curves between peak areas and contents of components in tea are linear within the suitable concentration range.R2 is 0.9999,the mean recovery rates of CAF in five kinds of tea are from 97.48% to 107.73%,and the relative standard deviations（RSD） are from 2.6% to 3.0%.