茶叶中没食子酸、儿茶素类和生物碱的 HPLC检测方法研究

比较 ZorbaxSB-C18与 TSKgelODS-100Z这2种色谱柱对12个组分的分离效果，从洗脱方式、流动相pH 值、柱温与流速等方面优化色谱条件，并对其进行方法学考查以及茶样测定应用，从而建立了一种同时测定茶叶中没食子酸（GA）、8种儿茶素类（GC、EGC、C、EGCG、EC、GCG、ECG、CG）与3种生物碱（可可碱、茶碱、咖啡碱）的高效液相色谱（HPLC）检测方法。确立的最优色谱条件为：采用 TSKgelODS-100Z （4．6mm×150mm，5μm）色谱柱，流动相为2‰甲酸水溶液（A 相）和甲醇（B相），洗脱方式为83％A （0 min）→75％A （5min）→73％A （7min）→58％A （16min）→83％A （18min），柱温为40℃，流速为1．0mL ·min－1，检测波长为280nm。茶叶中各组分回归方程的相关系数均在0．9990以上，保留时间与峰面积的精密度RSD 分别小于0．105％与4．076％，加标回收率在97．767％～104．766％。该方法具有良好的线性关系、精密度和回收率，对待测组分的分离效果好，适用于茶叶中没食子酸、儿茶素类及生物碱含量的准确测定。

Simultaneous HPLC Determination of Gallic Acid,Catechins and Alkaloids in Tea

Using HPLC,an analytical method was developed to simultaneously determine the contents of gallic acid（GA）,8 catechins （i.e.,GC,EGC,C,EGCG,EC,GCG,ECG and CG）and 3 alkaloids （i .e.,theobromine,theophylline and caffeine）in tea.Separation of the 1 2 chemicals on two chromatographic columns （Zorbax SB-C1 8and TSKgel ODS-1 00Z ） were investigated. The chromatographic conditions applied were the result fromoptimizations of the elution mode,pH of the mobile phase,column temperature and flow rate.They included：maintaining TSKgel ODS-1 00Z column at 40℃,using 2 ‰ formic acid-water solution （mobile phase A ）andmethanol （mobile phase B）with the gradient elution mode of 83 % A （0 min）→7 5 % A （5 min） →7 3 % A （7min）→5 8% A （16min）→83 % A （18min）at the flow rate of 1.0 mL·min-1 ,and detecting at the wavelength of 280nm.Methodological evaluation and application on 6 tea samples were subsequently conducted for verification.Thecorrelation coefficients of the resulting linear equations for all of the components were greater than 0.9 9 90,RSDs %of accuracy of the retention time and peak area lower than 0.1 05 % and 4.07 6 %,respectively,and the recoveryrates from 9 7.7 6 7 % to 1 04.7 6 6 %.It appeared that the newly developed analytical method could yield linearrelationships on data,as well as desirable precision,recovery and separability on the measurements for accurate andsimultaneous determinations of gallic acid,catechins and alkaloids in tea.