HPLC法同时测定茶叶中儿茶素类和咖啡因的含量

Simultaneous determination of some selected catechins and caffeine in tea by performance liquid chromatography

为了建立了一种等度洗脱茶叶中6种儿茶素类没食子儿茶素（GC）、表没食子儿茶素（EGC）、儿茶素（C）、表没食子儿茶素没食子酸酯（EGCG）、表儿茶素没食子酸酯（ECG）、表儿茶素（EC）及限量成分咖啡因（CAF）的高效液相色谱（HPLC）定量测定的方法,采用汉邦Benetnach TM C18（5μm×4.6mm×250mm）色谱柱,流动相为甲醇∶水∶磷酸（28∶72∶0.1,v/v/v）,流速为0.8m L·min-1,UV检测波长为280nm,柱温为30℃。结果表明GC、EGC、C、EGCG、ECG、EC和CAF分别在0.10～1.00、0.16～1.00、0.10～1.00、0.05～0.50、0.10～1.50、0.10～2.00和0.02～1.00mg·m L-1内线性关系良好,相关系数在0.9984～0.9999间;平均加样回收率为100.89%（EGCG）,99.07%（CAF）;样品分析中,除GC的分离度RS〉1外,其他6个成分RS均〉2。该方法简单、快速、准确、重现性好,可用于儿茶素类和咖啡因的定量检测。

The contents of six catechins （GC, EGC,C, EGCG, ECG and EC） and limited composition caffeine were investigated by HPLC method with Hanbon BenetnachTM C18 column（5μm×4.6mm×250mm） at 30℃ and the UV detection wavelength was 280nm. The mobile phase was methanol-water-phosphorus acid （28：72：0.1, v/v/v） isocratic elution system,and the flow rate was 0.8mL. min-1. The results showed that the linear ranges of GC,EGC,C,EGCG,ECG,EC and caffeine were 0.10-1.00,0.16-1.00,0.10～1.00,0.05～0.50,0.10～1.50,0.10- 2.00 and 0.02-1.00mg. mL-1 respectively, and the correlation coefficients were ranged from 0.9984～0.9999. The average recoveries of the two most abundant compositions EGCG and CAF were 100.89% and 99.07%, respectively. The resolutions of the six object components were more than 2,except GC. The method was simple, rapid,accurate, reproducible and ideal for routine analysis of catechins and caffeine.