Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Pardubice, Czech Republic.
J Sep Sci. 2009 Nov;32(21):3603-19. doi: 10.1002/jssc.200900344.
The retention of phenolic acid and flavone antioxidants was investigated on three columns with bonded PEG, hydroxy (DIOL) and mixed oxyethylene-hydroxy (Luna HILIC) stationary phases in buffered aqueous ACN mobile phases. All columns show mixed retention mechanism: reversed phases in highly aqueous mobile phases and normal phases (HILIC, hydrophilic interaction LC) in mobile phases with high concentration of ACN, showing characteristic U-shape retention versus mobile phase composition plots. Equations enabling description and prediction of retention of sample compounds over the full mobile phase composition range were compared. Dual retention mechanism offers possibilities for using differences in selectivity between the two separation modes on a single column to improve the separation of natural antioxidants. The Luna HILIC column shows larger HILIC retention range, enhanced retention, improved selectivity and better peak symmetry in comparison to the PEG and DIOL columns.
研究了在三种键合聚乙二醇（PEG）、羟（DIOL）和混合乙氧基-羟（Luna HILIC）固定相的色谱柱上，在缓冲的含水 ACN 流动相中酚酸和黄酮类抗氧化剂的保留情况。所有的色谱柱都显示出混合保留机制：在高水相的流动相中为反相，在高浓度 ACN 的流动相中为正相（亲水作用 LC，HILIC），表现出特征性的 U 形保留与流动相组成图。比较了描述和预测样品化合物在整个流动相组成范围内保留的方程。双重保留机制为在单根柱子上利用两种分离模式之间的选择性差异提供了可能性，以改善天然抗氧化剂的分离。与 PEG 和 DIOL 柱相比，Luna HILIC 柱具有更大的 HILIC 保留范围、增强的保留、改进的选择性和更好的峰对称性。
