Xu Xueqin, Ye Hongzhi, Wang Wei, Yu Lishuang, Chen Guonan
Department of Chemistry, Fuzhou University, Fuzhou, Fujian, China.
Talanta. 2006 Jan 15;68(3):759-64. doi: 10.1016/j.talanta.2005.05.027. Epub 2005 Jul 15.
Four flavonoids (rutin, hyperoside, quercitrin and quercetin) in Houttuynia cordata Thunb. and Saururus chinensis (Lour.) Bail. were determined by capillary electrophoresis with wall-jet amperometric detection. The working electrode was a 500 microm diameter carbon disc electrode and the detection potential was +0.95 V (versus Ag/AgCl). Effects of several important factors, such as the running buffer and its corresponding pH and concentration, separation voltage, injection time were investigated to acquire the optimum conditions for separation of these four flavonoids. Baseline separation for the four flavonoids was obtained within 21 min in a 60 cm length capillary at a separation voltage of 15 kV with a 60 mmoL/L Na(2)B(4)O(7)-120 mmoL/L NaH(2)PO(4) buffer (pH 8.8) as running buffer. The relationship between peak currents and analyte concentrations was linear over about two orders of magnitude with detection limits (defined as S/N=3) ranging from 0.02 to 0.05 microg/mL for all analytes. This method was applied for the determination of the above four flavonoids in H. cordata Thunb. and S. chinensis (Lour.) Bail. with simple extraction procedures, and the assay results were satisfactory.
采用毛细管电泳-壁喷安培检测法测定了鱼腥草和三白草中的四种黄酮类化合物（芦丁、金丝桃苷、槲皮苷和槲皮素）。工作电极采用直径为500微米的碳盘电极，检测电位为+0.95 V（相对于Ag/AgCl）。研究了运行缓冲液及其相应的pH值和浓度、分离电压、进样时间等几个重要因素的影响，以获得分离这四种黄酮类化合物的最佳条件。在60 cm长的毛细管中，以60 mmol/L Na₂B₄O₇-120 mmol/L NaH₂PO₄缓冲液（pH 8.8）为运行缓冲液，在15 kV的分离电压下，21分钟内实现了四种黄酮类化合物的基线分离。峰电流与分析物浓度之间的关系在大约两个数量级范围内呈线性，所有分析物的检测限（定义为S/N = 3）为0.02至0.05 μg/mL。该方法采用简单的提取程序用于测定鱼腥草和三白草中的上述四种黄酮类化合物，测定结果令人满意。
