Department of Chemistry and Biochemistry, University of Texas at Arlington , Arlington, Texas 76019, United States.
Anal Chem. 2017 Aug 15;89(16):8177-8191. doi: 10.1021/acs.analchem.7b00931. Epub 2017 Jul 12.
New stationary phases are continuously developed for achieving higher efficiencies and unique selectivities. The performance of any new phase can only be assessed when the columns are effectively packed under high pressure to achieve a stable bed. The science of packing columns with stationary phases is one of the most crucial steps to achieve consistent and reproducible high-resolution separations. A poorly packed column can produce non-Gaussian peak shapes and lower detection sensitivities. Given the ever larger number of stationary phases, it is impossible to arrive at a single successful approach. The column packing process can be treated as science whose unified principles remain true regardless of the stationary phase chemistry. Phenomenologically, the column packing process can be considered as a constant pressure or constant flow high-pressure filtration of a suspension inside a column with a frit at the end. This process is dependent on the non-Newtonian suspension rheology of the slurry in which the particles are dispersed. This perspective lays out the basic principles and presents examples for researchers engaged in stationary phase development. This perspective provides an extensive set of slurry solvents, hardware designs, and a flowchart, a logical approach to optimal column packing, thus eliminating the trial and error approach commonly practiced today. In general, nonaggregating but high slurry concentrations of stationary phases tend to produce well packed analytical columns with small particles. Conversely, C18 packed capillary columns are best packed using agglomerating solvents.
新的固定相不断被开发出来，以实现更高的效率和独特的选择性。只有在高压下有效地填充柱子以形成稳定的床层时，才能评估任何新相的性能。用固定相填充柱子的科学是实现一致且可重复的高分辨率分离的最关键步骤之一。填充不好的柱子会产生非高斯峰形和较低的检测灵敏度。鉴于固定相的数量越来越多，不可能采用单一的成功方法。柱子填充过程可以被视为一门科学，其统一的原则无论固定相化学如何都是成立的。从现象上看，柱子填充过程可以被视为在末端有 frit 的柱子内的悬浮液在恒压或恒流高压下的过滤。这个过程取决于悬浮液中非牛顿流变学，其中颗粒被分散。这种观点阐述了基本原理，并为从事固定相开发的研究人员提供了示例。这种观点提供了广泛的浆料溶剂、硬件设计和流程图，这是一种优化柱子填充的逻辑方法，从而消除了当今常用的反复试验方法。一般来说，非团聚但高浓度的固定相浆料往往会产生具有小颗粒的良好填充分析柱。相反，使用团聚溶剂可以最好地填充 C18 填充的毛细管柱。
