采用压力驱动的亲和毛细管电泳技术(P-ACE)分别研究了生理酸度条件下(p H 7.4)3种黄酮类化合物龙血素A、龙血素B和剑叶龙血素C与人血清白蛋白(HSA)之间的相互作用。利用蛋白淌度变化和药物浓度的关系,计算得出上述三者与HSA的结合常数K...采用压力驱动的亲和毛细管电泳技术(P-ACE)分别研究了生理酸度条件下(p H 7.4)3种黄酮类化合物龙血素A、龙血素B和剑叶龙血素C与人血清白蛋白(HSA)之间的相互作用。利用蛋白淌度变化和药物浓度的关系,计算得出上述三者与HSA的结合常数Ka分别为0.414×105,0.252×105,1.816×105L/mol。结果表明,P-ACE可作为研究药物与蛋白相互作用的简便可行方法。展开更多
Capillary electrophoresis (CE) has become a powerful tool for enantiomer separations during the last decade. Since 1993, the author has investigated enantiomer separations by affinity capillary electrophoresis (affini...Capillary electrophoresis (CE) has become a powerful tool for enantiomer separations during the last decade. Since 1993, the author has investigated enantiomer separations by affinity capillary electrophoresis (affinity CE) with some proteins and by cyclodextrin electrokinetic chromatography (CDEKC) with some charged cyclodextrins (CDs). Many successful enantiomer separations are demonstrated from our study in this review article. In the enantiomer separations by affinity CE, the deterioration of detection sensitivity was observed under high concentration of the protein in running solutions. The partial filling technique was practically useful to solve the serious problem. It allowed operation at high protein concentrations, such as 500 μmol/L, without the detection problem. Charged CDs had several advantages for the enantiomer separations over neutral ones. Strong electrostatic interactions between a charged CD and oppositely charged analytes should be effective for the formation of the complex. A large difference in electrophoretic mobility between the free analyte and the inclusion complex should also enhance the enantiomeric resolution. In CE mass spectrometry (CE MS), the partial filling technique was applied to avoid the introduction of nonvolatile chiral selectors into the CE MS interface. By replacing the nonvolatile electrolytes in the running buffer by volatile ones, the separation conditions employed in CE with the UV detection method could be transferred to CE MS.展开更多
文摘采用压力驱动的亲和毛细管电泳技术(P-ACE)分别研究了生理酸度条件下(p H 7.4)3种黄酮类化合物龙血素A、龙血素B和剑叶龙血素C与人血清白蛋白(HSA)之间的相互作用。利用蛋白淌度变化和药物浓度的关系,计算得出上述三者与HSA的结合常数Ka分别为0.414×105,0.252×105,1.816×105L/mol。结果表明,P-ACE可作为研究药物与蛋白相互作用的简便可行方法。
文摘本研究采用亲和毛细管电泳法(Affinity capillary electrop Horesis,ACE)对维拉帕米与牛血清白蛋白(Bovine Serum Albumin,BSA)的相互作用进行研究。以BSA为样品,以添加不同浓度药物的磷酸盐缓冲液(p H7.4,20 mmol·L^(-1))为背景缓冲溶液,采用以药物为添加剂的ACE方法,分别在25~oC和37~oC下进行毛细管电泳分离。根据各组分迁移时间,由Scatchard方程计算两个温度下药物与蛋白的结合常数K_b。实验结果表明,在ACE法中,随着药物浓度的增大,BSA与内标物的电泳迁移时间差值变大,由Scatchard方程计算得到维拉帕米与BSA在25~oC和37~oC时的K_b值分别为4.28×10~3M^(-1),ΔG为-20.73 k J·mol^(-1),ΔH为26.03 k J·mol^(-1),ΔS为157 J·mol^(-1)。在37℃时K_b值为6.43×10~3M^(-1),ΔG为-22.82 k J·mol^(-1),ΔH为26.03 k J·mol^(-1),ΔS为157 J·mol^(-1)。
文摘Capillary electrophoresis (CE) has become a powerful tool for enantiomer separations during the last decade. Since 1993, the author has investigated enantiomer separations by affinity capillary electrophoresis (affinity CE) with some proteins and by cyclodextrin electrokinetic chromatography (CDEKC) with some charged cyclodextrins (CDs). Many successful enantiomer separations are demonstrated from our study in this review article. In the enantiomer separations by affinity CE, the deterioration of detection sensitivity was observed under high concentration of the protein in running solutions. The partial filling technique was practically useful to solve the serious problem. It allowed operation at high protein concentrations, such as 500 μmol/L, without the detection problem. Charged CDs had several advantages for the enantiomer separations over neutral ones. Strong electrostatic interactions between a charged CD and oppositely charged analytes should be effective for the formation of the complex. A large difference in electrophoretic mobility between the free analyte and the inclusion complex should also enhance the enantiomeric resolution. In CE mass spectrometry (CE MS), the partial filling technique was applied to avoid the introduction of nonvolatile chiral selectors into the CE MS interface. By replacing the nonvolatile electrolytes in the running buffer by volatile ones, the separation conditions employed in CE with the UV detection method could be transferred to CE MS.
