Institut für Energie- und Umwelttechnik e V, Duisburg, Germany.
J Sep Sci. 2012 Jul;35(14):1723-30. doi: 10.1002/jssc.201101092. Epub 2012 Jun 18.
Solvent compatibility is a limiting factor for the success of two-dimensional liquid chromatography (2-D LC). In the second dimension, solvent effects can result in overpressures as well as in peak broadening or even distortion. A peak shape study was performed on a one-dimensional high-performance liquid chromatography (HPLC) system to simulate the impact of peak distorting solvent effects on a reversed-phase second dimension separation operated at high temperatures. This study includes changes in injection volume, solute concentration, column inner diameter, eluent composition and oven temperature. Special attention was given to the influence of high temperatures on the solvent effects. High-temperature HPLC (HT-HPLC) is known to enhance second dimension separations in terms of speed, selectivity and solvent compatibility. The ability to minimise the viscosity contrast between the mobile phases of both dimensions makes HT-HPLC a promising tool to avoid viscosity mismatch effects like (pre-)viscous fingering. In case of our study, viscosity mismatch effects could not be observed. However, our results clearly show that the enhancement in solvent compatibility provided by the application of high temperatures does not include the elimination of solvent strength effects. The additional peak broadening and distortion caused by this effect is a potential error source for data processing in 2-D LC.
溶剂兼容性是二维液相色谱（2-D LC）成功的限制因素。在第二维中，溶剂效应会导致过压以及峰展宽甚至变形。在一维高效液相色谱（HPLC）系统上进行了峰形研究，以模拟在高温下操作的反相二维分离中峰变形溶剂效应的影响。本研究包括进样体积、溶质浓度、柱内径、洗脱液组成和柱温的变化。特别关注高温对溶剂效应的影响。众所周知，高温高效液相色谱（HT-HPLC）可以提高二维分离的速度、选择性和溶剂兼容性。能够最小化两个维度的流动相之间的粘度对比度使得 HT-HPLC 成为一种有前途的工具，可以避免像（预）粘性指进这样的粘度不匹配效应。在我们的研究中，没有观察到粘度不匹配效应。然而，我们的结果清楚地表明，高温应用提供的溶剂兼容性增强并不包括消除溶剂强度效应。这种效应引起的额外的峰展宽和变形是二维 LC 数据处理中的潜在误差源。
