固相萃取-高效液相色谱法测定茶叶中儿茶素

Determination of Catechin in Tea by Solid State Extration-high Performance Liquid Chromatography

建立一种用高效液相色谱法测定茶叶中儿茶素的含量.方法:样品经乙醇提取,超声30min后,过C18小柱净化,样品溶液经0.45μm滤膜过滤后,用于HPLC分析.使用C18(5 um,150 mm×6.0 mm)色谱柱进行分离,用不同体积比混合的流动相A及流动相B的混合液作梯度淋洗,流速为1.0 ml/min,检测波长为280 nm,柱温为40℃.以甲醇∶水∶乙酸-26∶73.5∶0.5(体积比)为流动相.儿茶素在0.02～0.3 g/L范围内线性关系良好,回收率在98.2%～100.3%之间,相对标准偏差为1.6643%.该方法具有操作简便、快速、精密度高、回收率好、重现性较好、检测限低等优点.

This study to establish a method to determine the content of catechin in tea by HPLC. The samples were extracted by ethanol, with the treatment of ultrasonic 30 min and C18 SPE sample solution filtered through 0. 45 μm membrane for HPLC analysis. C18 （5 um, 150 mm × 6. 0 mm） column was used to separate, mixed with different volume ratio of mobile phase A and mobile phase B of the mixture for gradient elution with a flow rate at 1.0 mlY min, the detection wavelength at 280 nm, the column temperature at 40 ℃. The volume ratio of methanol, water, and acetic acid was 26： 73.5： 0. 5, which was used as the mobile phase. It is found that catechin in the range of 0. 02-0. 3 g/L has a good linear relationship, the recovery rate is between 98% -100. 3%, and the relative standard deviation is 1. 6643%. The method is simple and fast with high precision, high recovery, good repeat- ability, and low detection limit.