康砖茶中儿茶素、咖啡因、没食子酸HPLC-DAD分析

Analysis of catechin,caffeine and gallic acid in Kangzhuan tea by HPLC-DAD

采用二极管阵列检测器（DAD）和Acclaim TM 120色谱柱,建立了一种简单、灵敏分析茶叶中儿茶素、咖啡因（CAF）、没食子酸（GA）的高效液相色谱法。色谱条件：流动相为KH2PO4-乙腈系统,梯度洗脱,流速1.0m L/min,柱温25℃,进样量10μL,检测器波长为278nm。结果表明,6种儿茶素、咖啡因、没食子酸在一定范围内线性良好,相关系数为0.9991~0.9998,具有较低的日内和日间偏差,平均加标回收率在92.49%~106.08%之间,RSD小于3.59%。应用该方法对康砖茶进行分析,其GA、EGC、CAF、C、EC、EGCG、EGCG3＂Me、ECG含量分别在0.0717%~1.115%、0.280%~0.660%、2.728%~4.621%、0~0.0882%、0.157%~1.238%、0.343%~7.176%、0~0.172%及0.108%~1.654%。

A High- performance Liquid Chromatographyhigh method with a diode array detector（ DAD） and AcclaimTM120 as column,was established for simultaneous analysis of tea catechins,caffeine（CAF）,and gallic acid（GA）. Its chromatographic conditions were as follows ：mobile phase of KH2PO4 and acetonitrile,gradient elution,flow rate of 1.0m L/min,temperature of column 25℃,sample amount 10μL,Detector wavelength 278 nm.The results showed that six kinds of catechins,caffeine,gallic acid were in a range of good linearity correlation coefficient of 0.9991 to 0.9998,with low intra-and inter deviation,the average recovery between 92.49% ~106.08%,and the relative standard deviation（RSD） of less than 3.59%. Futhermore,This method was applied to analyze Kangzhuan tea,its GA,EGC,CAF,C,EC,EGCG,EGCG3＂Me,ECG contents were between 0.0717% ~1.115%,0.280%~0.660%,2.728%~4.621%,0~0.0882%,0.157%~1.238%,0.343%~7.176%,0~0.172% and0.108%~1.654%,respectively.