Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
Talanta. 2011 Jul 15;85(1):813-5. doi: 10.1016/j.talanta.2011.03.088. Epub 2011 Apr 8.
Aristolochic acid-I and aristolochic acid-II have been proved to be the main bioactive and toxic component in Aristolochia plants. As a result, the determination of their dissociation constants, which are important property parameters for weak acids, is highly desired for related pharmacological and toxicological studies. In this work, the dissociation constant values of aristolochic acid-I and aristolochic acid-II were determined by capillary electrophoresis using carboxymethyl chitosan-coated capillary, based on their electrophoretic mobilities by using nonlinear regression as well as linear regression, showing that the two models give comparable results. The data were also compared with those obtained by capillary electrophoresis with polybrene-coated capillary, and no conspicuous difference was observed. The correlation coefficients were all higher than 0.998 for both linear and nonlinear regression model. The pKa values were found to be 3.3±0.1 for aristolochic acid-I and 3.2±0.1 for aristolochic acid-II.
马兜铃酸-I 和马兜铃酸-II 已被证明是马兜铃属植物中的主要生物活性和毒性成分。因此，确定它们的离解常数（弱酸性物质的重要性质参数）对于相关的药理学和毒理学研究非常重要。在这项工作中，使用羧甲基壳聚糖涂覆的毛细管，通过毛细管电泳，基于它们的电泳迁移率，通过非线性回归和线性回归，确定了马兜铃酸-I 和马兜铃酸-II 的离解常数值，结果表明两种模型得出的结果相当。还将数据与用聚溴化乙锭涂覆的毛细管电泳获得的数据进行了比较，未观察到明显差异。线性和非线性回归模型的相关系数均高于 0.998。结果发现马兜铃酸-I 的 pKa 值为 3.3±0.1，马兜铃酸-II 的 pKa 值为 3.2±0.1。
