【摘要】 采用胶束电动色谱法(MEKC)建立了2类共11个中国红茶样品的色谱指纹图谱,结合模式识别技术对不同产地来源的红茶加以区分.红茶样品的处理方法:去离子水(100℃)浸取10 min.MEKC色谱条件:缓冲溶液25 mMNa2 HPO4-KH2 PO4-100 mM SDS-0.6%甲醇(V/V)-1 mM EDTA(pH7.0);柱温25℃;分离电压14 kV;检测波长200 nm;压力进样(0.5 psi进样5 s).实验结果:分离速度快,且重现性好,相对保留时间RSD小于2.0%,相对峰面积RSD小于6.0%.采用聚类分析法、主成分分析法、线性判别分析法和支持向量分类机模式分别对11种红茶样本进行了分类判断,结果与茶叶产地完全一致.表明该方法可用于红茶产地鉴别.更多还原

【Abstract】 A method was developed for geographical origins analysis of black teas from China using micellar electrokinetic chromatography(MEKC) and pattern recognition techniques.Tea samples were extracted with boiled water for 10 min.The running buffer was 25 mM phosphate solution(pH 7.0) containing 100 mM sodium dodecyl sulfate-1 mM EDTA-0.6% methanol.The applied voltage was 14 kV and the column temperature was set at 25 ℃.The detection was performed by UV absorption at 200 nm.The samples were injected by 0.5 psi pressure for 5 s.The RSDs of the related migration time and relative peak areas were less than 2.0% and 6.0%,respectively.Different pattern recognition techniques,including hierarchical cluster analysis(HCA),principal component analysis(PCA),Linear discriminate analysis(LDA) and support vector machine(SVM) were used for the classification of black teas from different places,and black tea samples were classified according to their geographical origins.Our primary results indicated that the MEKC combined with pattern recognition techniques should be used for the traceability of black teas from different areas.更多还原