聚硅氧烷离子液体用于快速气相色谱固定相的研究北大核心CSCD

合成了聚硅氧烷键合离子液体[PSOMIM][NTf2],并将其用作快速气相色谱柱的固定相。初步探索了采用短柱及小内径毛细管柱(3m×75μm i.d.)时的分离性能及固定相膜厚对分离性能的影响。与常规柱(8m×0.25mm i.d.)相比,在不损失分离度的前提下,分离速度可提高1~6倍;当膜厚为0.056μm时,可以将分离速度提高2~4倍。实验结果表明,聚硅氧烷键合离子液体固定相可以有效弥补由于缩短柱长所导致的分离度减小的问题,在快速气相色谱固定相方面具有较好的应用前景。     

聚硅氧烷键合离子液体的合成及色谱性能

提出了一种基于聚硅氧烷键合离子液体(PSOIL)的气相色谱固定相的方法, 即首先合成γ-氯丙基聚硅氧烷, 然后通过氯丙基与甲基咪唑的反应合成了聚硅氧烷负载的离子液体, 并对其色谱性能及分离选择性进行了评价.     

聚硅氧烷键合的离子液体用作高温气相色谱固定相的研究

合成了阴离子为二(三氟甲基磺酸酰)亚胺(NTf-2)的新型聚硅氧烷键合离子液体 ([PSOMIm][NTf2]),并采用静态涂渍法,制备了毛细管气相色谱柱.该固定相具有良好的热稳定性.热重测试显示,温度高于380 ℃后,[PSOMIm][NTf2]开始缓慢分解.色谱性能评价显示,此固定相对多种异构体和同系物均具有良好的分离选择性和高的热稳定性.对Grob试剂的分离结果表明,各种组分均能在柱上得到良好的分离且峰的对称性很好.此新型聚合物离子液体在高温气相色谱固定相的研究和应用方面具有较大的潜力.     

离子液体在气相色谱固定相中的应用

本文综述了离子液体在气相色谱固定相中的发展过程。为提高固定相的使用温度、选择性和色谱柱效,离子液体先后经历多次制备方法的改善,本文主要介绍了小分子离子液体、大体积离子液体、柱内烯基咪唑聚合离子液体、物理混配离子液体和化学键合离子液体等非手性离子液体的合成进展;同时综述了由手性氨基酸、手性胺和键合环糊精合成的手性离子液体的研究进展;并比较各种离子液体用作色谱固定相时的稳定性及选择性差异。另外,对离子液体在二维气相色谱和快速气相色谱中的应用扩展作了总结,并展望离子液体作为新型分离材料在气相色谱固定相中的研究和应用前景。     

离子液体/纤维素混配固定相分离性能研究

将丁基修饰的纤维素衍生物C-C4与离子液体键合聚硅氧烷PIL-C12-NTf2混配制成毛细管气相色谱柱C-C4@PIL-C12,用溶剂化参数模型对比研究了此固定相与商品化极性固定相Elite-waxetr和TG-17ms的作用力特征,并考察了此固定相的分离选择性等性能。结果表明,此类纤维素混配柱具有较高的柱效(萘,2778 plates/m,k=6.20,100℃)和较好的耐用性。其特征作用力为氢键碱性、偶极/极化作用以及氢键酸性作用,且强度适中;对芳香异构体、取代烷烃、脂肪酸酯、正构烷烃以及邻苯二甲酸酯的分离选择性优于商品化极性柱Elite-waxetr和TG-17ms。     

气相色谱手性固定相研究进展

本文评述了气相色谱手性分离的发展过程,介绍了氨基酸、二肽、金属配合物、环糊精、多糖、手性离子液体、环肽、键合以及交联类气相色谱手性固定相以及各类型的拆分机理,展望了气相色谱手性固定相的研究前景.     

气相色谱手性固定相研究进展

本文评述了气相色谱手性分离的发展过程,介绍了氨基酸、二肽、金属配合物、环糊精、多糖、手性离子液体、环肽、键合以及交联类气相色谱手性固定相以及各类型的拆分机理,展望了气相色谱手性固定相的研究前景.     

十二烷基苯磺酸锌毛细管气相色谱柱的制备及其用于含氧有机化合物的分析

采用汞塞动态法涂柱以十二烷基苯磺酸锌做为固定相制备了毛细管气相色谱柱 1 (固定液浓度为 9.3%W/V柱尺寸为 2 4m×0 .30mmi.d.) ,所用溶剂是丙酮 ,并且对柱性能进行了考察。实验表明这种色谱柱对C5 C8醇、酮、酯、C2 C8羧酸等具有较好的分离能力 ,尤其对强极性物质如羧酸 ,有独特的分离能力 ,峰形窄而对称 ,即使对痕量的羧酸也可直接做定量分析。     

气相色谱手性固定相研究进展

本文评述了气相色谱手性分离的发展过程,介绍了氨基酸、二肽、金属配合物、环糊精、多糖、手性离子液体、环肽、键合以及交联类气相色谱手性固定相以及各类型的拆分机理,展望了气相色谱手性固定相的研究前景。     

近年国内外毛细管气相色谱柱的进展和趋向

报道了近两年毛细管气相色谱柱的发展和趋向. 气相色谱柱制柱工艺是一个成熟的技术, 所以在制柱工艺方面的研究不够活跃. 近年新研究的固定相集中在常温离子液体和各种环糊精的衍生物. 近几年GC毛细管色谱柱的研究和改进集中在色谱柱厂家进行, 并立即成为商品柱. 本文对近两年一些重要期刊上发表的气相色谱论文进行了总结, 发现气相色谱分析所用的色谱柱大都使用毛细管柱, 并趋向于使用商品GC毛细管柱, 所使用的商品色谱柱中, 使用最多的是以含5%苯基的聚甲基硅氧烷做固定相的色谱柱, 其次是以100%甲基的聚硅氧烷做固定相的色谱柱. 极性毛细管色谱柱主要使用PEG、 OV-17和OV-1701固定相.     

Preparation and evaluation of a novel bonded imidazolium ionic liquid as stationary phase for gas chromatography

1‐Butyl‐3‐[(3‐trimethoxysilyl)propyl]imidazolium chloride ionic liquid was synthesized and chemically modified onto the inner wall of a fused capillary column as a stationary phase for gas chromatography. The 1‐butyl‐3‐[(3‐trimethoxysilyl)propyl]imidazolium chloride ionic liquid bonded capillary column was evaluated in detail. The results revealed that the ionic liquid bonded capillary column exhibited high column efficiency of 1.08 × 10⁴ plates/m, and good chromatographic separation selectivity (α ) for polar and non‐polar substances, and a good thermal stability between room temperature and 400°C. Moreover, the determination of thermodynamic parameters and the linear solvation energy relationship were further carried out. The results indicated that the chromatographic retention of each probe molecule on the ionic liquid bonded stationary phase was an enthalpy‐driven process, and the system constants of the linear solvation energy relationship signified that the dispersion interaction, the hydrogen bonding acidity and hydrogen bonding basicity were dominant interactions between probes and stationary phase among five interactions during the chromatographic separation. However, the contribution of each specific interaction for the stationary phase is ranked as the dispersion interaction > the hydrogen bonding basicity > the hydrogen bonding acidity.     

Incorporation of ionic liquid into porous polymer monoliths to enhance the separation of small molecules in reversed‐phase high‐performance liquid chromatography

An ionic liquid was incorporated into the porous polymer monoliths to afford stationary phases with enhanced chromatographic performance for small molecules in reversed‐phase high‐performance liquid chromatography. The effect of the ionic liquid in the polymerization mixture on the performance of the monoliths was studied in detail. While monoliths without ionic liquid exhibited poor resolution and low efficiency, the addition of ionic liquid to the polymerization mixture provides highly increased resolution and high efficiency. The chromatographic performances of the monoliths were demonstrated by the separations of various small molecules including aromatic hydrocarbons, isomers, and homologues using a binary polar mobile phase. The present column efficiency reached 27 000 plates/m, which showed that the ionic liquid monoliths are alternative stationary phases in the separation of small molecules by high‐performance liquid chromatography     

The use of precolumns for solvent focusing in capillary column gas chromatography

In trace analysis by capillary GC it is often desirable to use larger than normal injection volumes to obtain sufficient sensitivity. This, however, results in a wider solvent peak and tailing, and may reduce column efficiency. This paper describes the use of a short length of a capillary precolumn coated with a stationary phase of polarity similar to that of the sample solvent and a film thickness greater than that of the analytical column; provided the right combination of polarities of injection solvent and liquid phases are used, the precolumn focuses the solvent band, thereby enabling the maximum injection volume to be increased without measurably reducing efficiency. Typical precolumn dimensions are 1 m length, 0.32 mm i.d., and 0.5 μm stationary phase film thickness. Using a precolumn increases the maximum injection volume up to 8 or 10 μl, or three times that appropriate for a conventional analytical column, with little or no loss in efficiency.     

Gas chromatography of hydrocarbons using packed liquid chromatographic capillary columns

Capillary columns of 0.3-0.5 mm i.d. packed with 3- to 30-μm silica-based stationary phases for liquid chromatography were used for gas chromatographic separation of hydrocarbons. Column efficiencies were evaluated for various commercially available packing material. The best column efficiency was achieved with 5-μm octadecyl group bonded silica gel, the surface of which was coated with a poly (dimethylsiloxane) film. The 30-cm column produced 11,000 theoretical plates.     

核苷与碱基的苯胺甲基键合硅胶固定相高效液相色谱分离

建立苯胺甲基键合硅胶固定相(PAMS)高效液相色谱分离核苷与碱基的方法；研究流动相有机溶剂浓度、磷酸缓冲液pH值、离子强度对核苷和碱基在该键合固定相上的色谱保留及分离选择性的影响，用磷酸缓冲液(pH＝4)为流动相快速分离了部分核苷与碱基。     

以衍生化聚硅氧烷为固定相的开管毛细管电色谱柱的研制

建立了一种简单可行的制备衍生化聚硅氧烷开管毛细管电色谱柱的方法,石英毛细管无需浸蚀,直接键合上大分子的聚硅氧烷,用异丁烯酸丁酯和乙烯基磺酸衍生化时对苯的同系物有很好的分离能力,对甲苯柱效可达1.52×10⁵N/m(N为理论塔板数),柱效稳定;当用烯丙基全甲基β-环糊精和乙烯基磺酸衍生化时,石英毛细管先经溶胶-凝胶处理后,所制得的柱子对萘普生对映体的分离度可达0.81.     

一类新的毛细管气相色谱固定液—侧链液晶冠醚聚硅氧烷的研究

合成了一种新的毛细管气相色谱用固定液——侧链含冠醚液晶的聚硅氧烷,这种固定液易于涂渍在弹性石英毛细管柱上,柱效高,热稳定性好,极性中等,它具有高分子液晶和高分子冠醚固定液的双重保留性能,适于分离多种异构体。     

Ionic liquid‐bonded polysiloxane as stationary phase for capillary gas chromatography

Ionic liquid (IL) stationary phase is especially suitable for separation of complex samples, owing to the “dual nature” of IL. In this study, a synthetic method of ionic liquid‐bonded polysiloxane (PSOIL) as stationary phase of GC was proposed. Then, the PSOIL was used to prepare an 8 m capillary column by static method. The column efficiency was measured to be about 4000 plates/m (k=3.55, naphthalene) after the column had been conditioned at 210°C. The durability of PSOIL column was better than that of the mixed stationary phase of IL and OV‐1. Moreover, the Abraham solvation parameter model was employed to characterize the PSOIL. The result revealed that the PSOIL had stronger dispersion force (l) than neat IL and stronger hydrogen bond basicity (a) than DB‐1. That meant the PSOIL might offer good selectivity for both polar and non‐polar analytes. The column exhibited unique selectivity for various organic substances, such as the homologous compounds of alkanes, esters, alcohols and aromatic compounds. It was also found that some aromatic positional isomers could be separated better on the PSOIL column than on the DB‐1 column. Furthermore, the stationary phase was suitable for separation of high‐boiling point compounds such as polycyclic aromatic hydrocarbons, phthalic esters, etc. All of these demonstrated that the PSOIL offered good selectivity and high separation efficiency for a wide range of analytes.