A method was established using hollow fiber-liquid phase microextraction（HF-LPME） followed by high performance liquid chromatography（HPLC） to determine the concentration of the free（unbound） drug in the solution...A method was established using hollow fiber-liquid phase microextraction（HF-LPME） followed by high performance liquid chromatography（HPLC） to determine the concentration of the free（unbound） drug in the solution of the drug and protein. Measurements of drug-protein binding ratios and free drug concentrations were then analyzed with the Klotz equation to determine the equilibrium binding constant and number of binding sites for drug-protein interaction. The optimized method allows one to perform the efficient extraction and separation of free drug from protein-bound drug, protein, and other interfering substances. This approach was used to characterize the binding of the anticholinergic drugs atropine sulfate and scopolamine hydrobromide to proteins in human plasma and bovine serum albumin（BSA）. The results demonstrate the utility of HF-LPME method for measuring free drug concentrations in protein-drug mixtures and determining the protein binding parameters of a pharmacologically important class of drugs.展开更多
基金Supported by the National Natural Science Foundation of China(No.81041084)the Natural Science Foundation of Shanxi Province, China(No.2007011086)the Undergraduate Innovation Fund of Taiyuan City, China(No.08122034)
文摘A method was established using hollow fiber-liquid phase microextraction（HF-LPME） followed by high performance liquid chromatography（HPLC） to determine the concentration of the free（unbound） drug in the solution of the drug and protein. Measurements of drug-protein binding ratios and free drug concentrations were then analyzed with the Klotz equation to determine the equilibrium binding constant and number of binding sites for drug-protein interaction. The optimized method allows one to perform the efficient extraction and separation of free drug from protein-bound drug, protein, and other interfering substances. This approach was used to characterize the binding of the anticholinergic drugs atropine sulfate and scopolamine hydrobromide to proteins in human plasma and bovine serum albumin（BSA）. The results demonstrate the utility of HF-LPME method for measuring free drug concentrations in protein-drug mixtures and determining the protein binding parameters of a pharmacologically important class of drugs.
文摘目的在正相色谱条件下建立了托吡卡胺、氢溴酸后马托品、硫酸阿托品和山莨菪碱共4种阿托品类药物的对映体分离方法。方法使用Chiralpak IC[纤维素-三(3,5-二氯苯基氨基甲酸酯)共价键合硅胶]手性色谱柱,考察了不同流动相体系、烷醇体积比、酸碱添加剂、柱温以及流速对对映体分离的影响。结果 4种药物均可达到良好的分离度,通过不断优化色谱分离条件最终确定分离4种药物的最佳流动相条件:柱温为25℃,流速为1.0 m L·min-1,分离托吡卡胺对映体的流动相为正己烷-乙醇-二乙胺(体积比70∶30∶0.05),分离氢溴酸后马托品和硫酸阿托品对映体的流动相为正己烷-乙醇-二乙胺(体积比80∶20∶0.05),在最佳条件下3种药物对映体之间的分离度分别为7.73、2.36和2.67。分离山莨菪碱4个对映体的最佳流动相为正己烷-异丙醇-乙酸-二乙胺(体积比70∶30∶0.05∶0.025)。结论纤维素键合手性固定相对除山莨菪碱以外的3种抗胆碱能药物均能达到完全分离。
