Sholokhova Anastasia Yu, Borovikova Svetlana A
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31 Leninsky Prospect, GSP-1, 119071 Moscow, Russia.
Molecules. 2024 Aug 6;29(16):3721. doi: 10.3390/molecules29163721.
At present, stationary phases based on ionic liquids are a promising and widely used technique in gas chromatography, yet they remain poorly studied. Unfortunately, testing of "new" stationary phases is often carried out on a limited set of test compounds (about 10 compounds) of relatively simple structures. This study represents the first investigation into the physicochemical patterns of retention of substituted (including polysubstituted) aromatic alcohols on two stationary phases of different polarities: one based on pyridinium-based ionic liquids and the other on a standard polar phase. The retention order of the studied compounds on such stationary phases compared to the standard polar phase, polyethylene glycol (SH-Stabilwax), was compared and studied. It was shown that pyridinium-based ionic liquids stationary phase has a different selectivity compared to the SH-Stabilwax. Using a quantitative structure-retention relationships (QSRR) study, the differences in selectivity of the two stationary phases were interpreted. Using CHERESHNYA software, the importance of descriptors on different stationary phases was evaluated for the same data set. Different selectivity of the stationary phases correlates with different contributions of descriptors for the analytes under study. For the first time, we show that in-column dehydration is observed for some compounds (mostly substituted benzyl alcohols). This effect is worthy of further investigation and requires attention when analyzing complex mixtures. It suggests that when testing "new" stationary phases, it is necessary to conduct tests on a large set of different classes of compounds. This is because, in the case of using ionic liquids as an stationary phase, a reaction between the analyte and the stationary phase is possible.
目前，基于离子液体的固定相是气相色谱中一种很有前景且广泛应用的技术，但对其研究仍很不足。不幸的是，“新型”固定相的测试通常是在一组结构相对简单的有限测试化合物（约10种化合物）上进行的。本研究首次探究了取代（包括多取代）芳香醇在两种不同极性固定相上的保留物理化学规律：一种基于吡啶鎓离子液体，另一种基于标准极性相。比较并研究了所研究化合物在这些固定相与标准极性相聚乙二醇（SH-Stabilwax）上的保留顺序。结果表明，基于吡啶鎓离子液体的固定相与SH-Stabilwax相比具有不同的选择性。通过定量结构-保留关系（QSRR）研究，解释了两种固定相选择性的差异。使用CHERESHNYA软件，针对同一数据集评估了不同固定相上描述符的重要性。固定相的不同选择性与所研究分析物描述符的不同贡献相关。我们首次表明，某些化合物（主要是取代苄醇）会出现柱内脱水现象。这种效应值得进一步研究，在分析复杂混合物时需要引起注意。这表明在测试“新型”固定相时，有必要在一大组不同类别的化合物上进行测试。这是因为，在使用离子液体作为固定相的情况下，分析物与固定相之间可能会发生反应。
