Australian Centre for Research on Separation Science, School of Chemistry, Monash University, Melbourne, Australia.
J Sep Sci. 2013 Jul;36(14):2217-22. doi: 10.1002/jssc.201300143. Epub 2013 Jun 18.
The retention behaviour of amino acids was studied in hydrophilic LC on zwitterionic stationary phases. Evaluation of the influences of acetonitrile/water content, ammonium acetate (NH4Ac) concentration and mobile phase pH values was performed. Fourteen amino acids were tested and they were all retained to varying extents, with poorer retention in high water content eluents. The linear relationship between the logarithm of retention factor and log(water content) indicated that adsorption dominated or at least was partly involved in the separation mechanism. Electrostatic and hydrophilic interactions also contributed to the retention of these amino acids under different separation conditions with various mobile phase pH values and NH4Ac concentrations. Thus, the overall retention mechanism could be explained as a combination of adsorption, electrostatic and hydrophilic interactions. The magnitude and contribution of each mechanism is dependent on the nature of the analyte and the separation conditions applied.
在亲水液相色谱中，研究了氨基酸在两性离子固定相上的保留行为。评估了乙腈/水含量、乙酸铵（NH4Ac）浓度和流动相 pH 值的影响。测试了 14 种氨基酸，它们都在不同程度上被保留，在高水含量洗脱液中保留较差。保留因子的对数与 log(水含量)的线性关系表明，吸附作用主导或至少部分参与了分离机制。在不同的分离条件下，随着流动相 pH 值和 NH4Ac 浓度的变化，静电和亲水相互作用也有助于这些氨基酸的保留。因此，整体保留机制可以解释为吸附、静电和亲水相互作用的组合。每种机制的大小和贡献取决于分析物的性质和应用的分离条件。
