【摘要】 以绿茶为样本,以GB/T 8305–1987水浸出方式作为样品的提取方法,使用C18色谱柱(150 mm×4.6mm,5μm),以A相(超纯水)、B相(N–N二甲基甲酰胺︰甲醇︰冰乙酸=40︰2︰1.5)为流动相,在最佳梯度洗脱条件下对8种组分进行分离,紫外检测器检测,检测波长为278 nm,外标法定量。没食子酸、咖啡碱、表没食子儿茶素、儿茶素、表儿茶素、表没食子儿茶素没食子酸酯、没食子基儿茶素没食子酸酯和表儿茶素没食子酸酯8种组分的进样质量分别在0.0243~0.1456,0.2549~1.5296,0.2027~1.2164,0.0182~0.1102,0.1606~0.9634,1.0004~6.0024,0.018 2~0.109 0,0.229 6~1.377 4μg范围内与色谱峰面积的线性关系良好(r为0.991 0~0.999 9);加标回收率为98.60%~100.17%,RSD均小于0.48%(n=3)。对样品进行6次重复测定,与标准方法相比,8种组分测定结果的相对偏差为0.47%~5.55%。该方法简便、快速、准确、稳定、重复性好,可用于茶叶中8种成分的定量分析。更多还原

【Abstract】 Water extraction in GB/T 8305–1987 was as the sample pretreatment method, with a C18column(150mm×4.6 mm, 5μm), the mobile phase as: phase A of ultra-pure water and phase B of N-N dimethyl formamide–methanol–acetic acid(40︰2︰1.5), 8 components in green tea sample were gradient elution separation, and determined with UV detector at 278 nm. The external standard was adopted for the assay. There was good linearity between the1ogarithm values and the peak areas of GA, CAF, EGC, +C, EC, EGCG, GCG, ECG and in the ranges of 0.024 3–0.145 6,0.254 9–1.529 6, 0.202 7–1.216 4, 0.018 2–0.110 2, 0.160 6–0.963 4, 1.000 4–6.002 4, 0.018 2–0.109 0, 0.229 6–1.377 4μg respectively. Recoveries of the eight components were 98.60%–100.17%, RSDs were all below 0.48%(n=3). The samples were measured for 6 times repeatedly, compared with the results by GB/T 8313–2008, the relative deviations were0.47%–5.55%(n=6). The method is simple, rapid, accurate, stable, reproducible, and suitable for the quantitative analysis of catechins, caffeine and those 8 components.更多还原