USE OF SECONDARY CHEMICAL-EQUILIBRIA IN LIQUID-CHROMATOGRAPHY TO DETERMINE DISSOCIATION-CONSTANTS OF LEUKOTRIENE B-4, AND PROSTAGLANDIN B-2

被引：17

作者：

HARDCASTLE, JE

HE, M

BEGUM, B

VERMILLIONSALSBURY, R

机构：

[1] Department of Chemistry and Physics, Texas Woman's University, Denton

来源：

JOURNAL OF CHROMATOGRAPHY A | 1995年 / 691卷 / 1-2期

关键词：

D O I：

10.1016/0021-9673(94)00768-5

中图分类号：

Q5 [生物化学];

学科分类号：

071010 ; 081704 ;

摘要：

The secondary chemical equilibrium of a monoprotic acid in reversed-phase high-performance liquid chromatography (RP-HPLC) is controlled both by the pH of aqueous component and the ratio of organic solvent to water in the mobile phase. The pH dependence of capacity factors of a monoprotonic acid follows the titration curve of the acid. The midpoint of the sigmoidal curve corresponds to the pK(a) value of the acid. Therefore, the pK(a) of the acid can be determined by RP-HPLC. Capacity factors of prostaglandin B-2 and leukotriene B-4 were measured at several mobile phase pH values, and acetonitrile mobile phase compositions. pK(a) values determined at various ratios of acetonitrile to water were plotted against percent acetonitrile. The straight line that resulted was extrapolated to 100% aqueous solution. The thermodynamic pK(a) values of prostaglandin B-2 and leukotriene B-4 were determined to be 5.07 and 5.17, respectively.

引用

页码：225 / 229

页数：5

共 7 条

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