Caltabiano Anna M, Foley Joe P, Striegel André M
Analytical Sciences and Development, GlaxoSmithKline, 1250 S. Collegeville Rd., Collegeville, PA, 19426, USA; Department of Chemistry, Drexel University, 3141 Chestnut St., Philadelphia, PA, 19104, USA.
Department of Chemistry, Drexel University, 3141 Chestnut St., Philadelphia, PA, 19104, USA.
J Chromatogr A. 2018 Jan 12;1532:161-174. doi: 10.1016/j.chroma.2017.12.007. Epub 2017 Dec 6.
The size-exclusion separation of a water-soluble polyelectrolyte polymer, sodium polystyrene sulfonate (NaPSS), was demonstrated on common reversed-phase (C C, phenyl, and cyano) and hydrophilic interaction chromatography (HILIC) columns. The effect of common solvents - acetonitrile (ACN), tetrahydrofuran (THF), and methanol (MeOH), used as mobile phase modifiers - on the elution of NaPSS and the effect of column temperature (within a relatively narrow range corresponding to typical chromatographic conditions, i.e., 10 °C-60 °C) on the partition coefficient, K, were also investigated. Non-size-exclusion chromatography (non-SEC) effects can be minimized by the addition of an electrolyte and an organic modifier to the mobile phase, and by increasing the column temperature (e.g., to 50 °C or 60 °C). Strong solvents such as THF and ACN are more successful in the reduction of such effects than is the weaker solvent MeOH. The best performance is seen on medium polarity and polar stationary phases, such as cyanopropyl- and diol-modified silica (HILIC), where the elution of the NaPSS polyelectrolyte is by a near-ideal SEC mechanism. Hydrophobic stationary phases, such as C, C, and phenyl, require a higher concentration of a strong solvent modifier (THF) in the mobile phase to reduce non-SEC interactions of the solute with the stationary phase.
在常见的反相（C18、苯基和氰基）和亲水相互作用色谱（HILIC）柱上，展示了水溶性聚电解质聚合物聚苯乙烯磺酸钠（NaPSS）的尺寸排阻分离。还研究了用作流动相改性剂的常见溶剂——乙腈（ACN）、四氢呋喃（THF）和甲醇（MeOH）对NaPSS洗脱的影响，以及柱温（在对应于典型色谱条件的相对较窄范围内，即10℃ - 60℃）对分配系数K的影响。通过向流动相中添加电解质和有机改性剂，以及提高柱温（例如至50℃或60℃），可以使非尺寸排阻色谱（non-SEC）效应最小化。强溶剂如THF和ACN在减少此类效应方面比弱溶剂MeOH更成功。在中等极性和极性固定相上，如氰丙基和二醇改性的硅胶（HILIC），可以看到最佳性能，其中NaPSS聚电解质的洗脱遵循近乎理想的尺寸排阻色谱机制。疏水固定相，如C18、C8和苯基，需要在流动相中使用更高浓度的强溶剂改性剂（THF），以减少溶质与固定相之间的非尺寸排阻相互作用。
