Retention modelling of electrostatic and adsorption effects of aliphatic and aromatic carboxylic acids in ion-exclusion chromatography.
Retention modelling of electrostatic and adsorption effects of aliphatic and aromatic carboxylic acids in ion-exclusion chromatography.
复制标题
离子排斥色谱中脂肪族和芳香族羧酸的静电和吸附效应的保留模型。
DOI：
10.1016/s0021-9673(99)00735-9
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
K. Tanaka
中科院分区：
文献类型：
--
作者：
K. Ng;B. Paull;P. Haddad;K. Tanaka
在同时考虑静电排斥效应和疏水吸附效应的情况下，研究了离子排斥色谱中脂肪族和芳香族羧酸的保留机制。分析物的保留因子与流动相组成（硫酸浓度和甲醇百分比）、分析物类型（pKa 和疏水性）以及固定相的一些物理特性之间的数学关系已得到推导。选择 13 种羧酸（包括一价和二价、脂肪族和芳香族酸），使用 14 种不同 pH 值和甲醇百分比的流动相组合物，获取三种不同阳离子交换固定相（其中磺酸根官能团与聚苯乙烯-二乙烯基苯、聚甲基丙烯酸酯或二氧化硅结合）的保留数据。这些保留数据用于导出使用非线性回归求解保留模型所需的参数。通过这种方式，获得了吸附现象对分析物保留影响的定量测量。然后使用该模型来优化九种羧酸的分离。
The retention mechanism of aliphatic and aromatic carboxylic acids in ion-exclusion chromatography has been investigated with consideration of simultaneous electrostatic repulsion effects and hydrophobic adsorption effects. A mathematical relationship between the retention factor of the analyte and the mobile-phase composition (sulfuric acid concentration and percentage of methanol), the type of analyte (pKaand hydrophobicity) and some physical characteristics of the stationary phase has been derived. Thirteen carboxylic acids (comprising mono- and divalent, aliphatic and aromatic acids) were chosen and used to acquire retention data on three different cation-exchange stationary phases (in which the sulfonate functional groups are bound to polystyrene–divinylbenzene, polymethacrylate or silica) using 14 mobile-phase compositions of varying pH and percent methanol. These retention data were used to derive the parameters necessary to solve the retention model using non-linear regression. In this way, a quantitative measure of the effects of adsorption phenomena on analyte retention were obtained. The model was then used to optimise the separation of nine carboxylic acids.