Appulage Dananjaya K, Schug Kevin A
Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX 76019, USA.
Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX 76019, USA.
J Chromatogr A. 2017 Jul 21;1507:115-123. doi: 10.1016/j.chroma.2017.05.073. Epub 2017 Jun 3.
Silica hydride, or Type C silica, has been developed as an alternative chromatographic support material for liquid chromatography. There are various bonded phases available with this new support. For four such phases (Cholesterol, Bidentate C18, Diamond Hydride, and Diol), retention and selectivity behavior were investigated using liquid chromatography coupled with triple quadrupole mass spectrometry. A set of small molecules from several chemical classes of interest, and varying in their physicochemical properties, were chromatographed under both reversed-phase and aqueous normal phase modes. To screen the columns, column switching was performed using an automated platform controlled by associated software and an additional valve. A typical scouting gradient was implemented. The separation conditions were not further optimized since the goal was simply to evaluate the variable retention behavior of the phases and selectivity under generic conditions. Further, retention of the analytes were evaluated under isocratic conditions with varying percentages of organic phase to visualize the potential for dual retention modes on the same column for certain analytes. Four analytes (fentanyl, hydrocodone, hydromorphone, and matrine) showed dual mode retention behavior with all four phases. Especially, fentanyl exhibited dramatic "U-shaped" retention profiles on Cholesterol and Bidentate C18 phases. Overall, changes in the retention order between reversed phase and aqueous normal phases emphasized the potential for altered selectivity. Results showed that the Cholesterol phase provided the highest retention for most analytes compared to the other phases. The more polar Diol phase still provided good retention in reversed phase mode. Retention and selectivity were all highly reproducible.
氢化硅，即C型硅胶，已被开发用作液相色谱的替代色谱支持材料。这种新型支持材料有多种键合相可供选择。对于其中四种键合相（胆固醇、双齿C18、氢化金刚石和二醇），使用液相色谱与三重四极杆质谱联用研究了保留和选择性行为。一组来自几个感兴趣化学类别的小分子，其物理化学性质各不相同，在反相和水正相模式下进行了色谱分析。为了筛选色谱柱，使用由相关软件和一个额外阀门控制的自动化平台进行柱切换。实施了典型的探索性梯度。由于目标只是在一般条件下评估各键合相的可变保留行为和选择性，因此分离条件未进一步优化。此外，在等度条件下，使用不同百分比的有机相评估分析物的保留情况，以观察某些分析物在同一色谱柱上的双重保留模式的潜力。四种分析物（芬太尼、氢可酮、氢吗啡酮和苦参碱）在所有四种键合相上均表现出双重模式保留行为。特别是，芬太尼在胆固醇和双齿C18键合相上呈现出显著的“U形”保留曲线。总体而言，反相和水正相之间保留顺序的变化强调了选择性改变的潜力。结果表明，与其他键合相相比，胆固醇键合相对大多数分析物的保留能力最强。极性更强的二醇键合相在反相模式下仍具有良好的保留能力。保留和选择性都具有高度的可重复性。
