ATB引发交联DEGS弹性石英毛细管柱的研究

选择性好、强极性、耐高温的交联弹性石英毛细管色谱柱仍是当前毛细管制柱方面的重要研究课题     

偶氮特异丁烷引发交联OV-1701石英弹性毛细管色谱柱的研究

ATB(偶氮特异丁烷)是一类性能良好的自由基引发剂、用它引发交联OV-1701石英弹性毛细柱,交联度大于96％,柱子内壁惰性,柱效高,热稳定性好,交联前后柱极性无明显变化,文中还对交联条件和反应机理进行了研究和探讨。     

臭氧法交联OV-701弹性石英毛细管柱的研制

用臭氧引发交联聚硅氧烷固定液的方法,操作方便,设备简单。1987年,我们用臭氧为引发剂,在弹性石英毛细管柱上交联非极性固定液SE-54、SE-33、OV-1等,取得较为满意的结果。但用臭氧法     

FFAP交联玻璃毛细管柱的研制和应用

极性固定液的交联是比较困难的。继聚乙二醇20M(PEG20M)交联柱的研究,近年来极性固定液交联的研究有了较大进展,中等极性的氰基硅酮,二乙二醇丁二酸聚酯交联也有报道。聚乙二醇20M和2-硝基对苯二甲酸的反应产物(FFAP)有报道交联的柱子呈强酸性,没有说明交联条件。这是一种用途很广的极性固定液,因而仍是一项值得研究的工作。本文对交联剂的用量、交联温度进行了考查,得到柱子的交联度、理论板数、酸碱比分别为85％、3000/m、0.96左右,并在275℃温度下考查了耐温性能。各类样品在该柱上获得了很好分离。     

聚苯撑基硅氧烷交联毛细管柱的研究

使用静态涂渍法,在毛细管柱内壁涂渍新型苯撑基色谱固定液,通过原位交联,提高了液膜不可抽提性及稳定性。苯基通常被连接在聚硅氧烷硅原子的侧链上,如果两个硅原子之间通过苯联结而不是通过氧原子联结,则可形成聚苯撑基硅氧烷［１］,这种聚硅氧烷的弹性好。采用含５０％聚苯撑基硅氧烷研制出交联毛细管柱,并对制备过程重复程度进行了考察,评价了柱子的综合性能,简单介绍了柱子的极性及适用范围。     

大口径特厚液膜交联毛细管柱的性能和应用

本文研究了自制的内径为0.6～0.8mm液膜厚度约为5μm的二甲基聚硅氧烷交联玻璃毛细管柱的性能和应用。用氮作载气时多数柱之理论柱效利用率(UTE%)为70—80%。用正癸烷测定其样品容量为37μg。该柱可与直接进样器相连,代替填充柱直接进样作常规分析,能达到高效快速之目的。     

冠醚聚硅氧烷弹性石英毛细柱交联方法的研究

]本文研究了冠醚聚硅氧烷作为石英毛细管柱固定液的交联方法,优化交联条件,并对交联方法进行了对比和讨论,其中,偶氮特丁烷作为交联引发剂交联效果优于过氧化二异丙苯引发剂,其交联效率大于95%,柱效高于4500块／米,300℃时柱流失基线漂移量为2.710-13A酚油和二苯酮乙基取代混合物在交联柱上得到良好分离。最后,还对冠醚聚硅氧烷的分离机理进行了初步探。     

Preparation of Fritless Packed Silica Columns for Capillary Electrochromatography

Fritless packed silica gel columns were prepared using sol‐gel technology. A part of a 75 μm i.d. fused silica capillary was filled with a mixture of tetramethoxysilane and poly(ethylene glycol). After gelling at 40°C and heating at 300°C, the resultant silica gel was derivatized with dimethyloctadecylchlorosilane. A scanning electron micrograph of a cross‐section of the capillary column showed that the gel took the form of a spherical particle aggregate and adhered to the column inner wall. The column performance was evaluated for electrochromatography using acetonitrile–50 mM HEPES buffer (pH 6.6) (60/40 or 40/60, v/v) as the mobile phase. An electroosmotic flow of 1.0 mm/s was generated with (60/40, v/v) acetonitrile/HEPES buffer at a field strength of 546 V/cm. Using a sol‐gel‐derived packed column at an electroosmotic flow of 0.5 mm/s, efficiencies of up to 1.1×10⁵ plates/m were obtained for retained solutes.     

Effects of Permeation of Helium through the Walls of Fused Silica Capillary GC Columns

Hold-up times and peak widths have been measured in long fused silica GC capillary columns at high temperature with helium as the carrier gas. The results lead to the conclusion that the helium permeates through the column walls. The conventional Poiseuille theory of carrier gas flow has been extended to include this phenomenon. The resulting “loss modified Poiseuille” model, which uses literature values for the permeability of fused silica to helium, has been used to simulate the observed behavior. Good agreement between simulation and experiment validates the model. Simulations have been used to explore the effect of column permeability on hold-up times, peak widths, and velocity profiles over a broad range of column geometries.     

含杯[4]芳烃毛细管固定相的制备与色谱性能

杯芳烃是由对位取代的苯酚在邻位通过亚甲基连接起来的环状化合物,由于具有可调节大小的空腔,不仅能络合无机离子,而且还可络合有机分子,在分析分离方面有极好的应用前景［１,２］．杯芳烃已用于气相色谱［３,４］、离子选择性萃取［５,６］、液相色谱［７,８］和...     

A Study of the Human Urinary Steroid Metabolic Profile Using A DB-1 Fused Silica Capillary Column

This paper reports the performance of a DB-1 fused-silica capillary column for analysis of mixtures of methoxime-trimethylsilyl ether (MO-TMS) derivatives of human urinary steroid extracts. DB-1 is a non-extractable bonded phase, equivalent in polarity to SE-30 and OV-1. In addition, a small reversed-phase Sep-Pak C₁₈ cartridge is used for extraction of steroid conjugates from urine, and for the extraction of freed steroids liberated by hydrolysis. Examples of urinary steroid analysis in normal adult males and in patients with multiple myeloma using the DB-1 bonded phase fused silica capillary column are described.     

Fast Analysis of Capillary Electrochromatography with Non-Porous ODS as the Stationary Phase

ABSTRACT

High-speed capillary electrochromatography was developed on both short and long packed columns with 2 μm non-porous ODS as the stationary phase. Factors that affect the analysis time of samples, such as voltage, electrolyte concentration, pH and organic modifier concentration in the mobile phase, were studied systematically. Fast analysis of aromatic compounds within 13 seconds was realized with column efficiency of 573,000 plates/m and a R.S.D.% of the retention times of all components in 8 consecutive injections below 1.0%, which demonstrated the high efficiency and high reproducibility of such a technique. In addition, DNPH derived aldehydes and ketones in both standards and environmental samples were separated with high speed.     

缬氨霉素作为毛细管气相色谱新型固定相的性能研究

本文研究了缬氨霉素的气相色谱特性, 考察了它们对一些难分离物质对、位置异构体以及一些手性化合物的分离效果. 除文献[3]外, 目前尚未见到有关将环状肽作为色谱固定相的报道.     

一种新的改性聚乙二醇毛细管气相色谱固定相

合成了一种新的聚乙二醇衍生物，将其用作毛细管气相色谱固定相，研究了其色谱性能，并成功地分离了二甲苯、氯甲苯、溴甲苯、二氯苯等二取代苯位置异构体；并对其手性分离能力进行了初步研究和讨论。     

双苯甲酰胺冠醚固定相的合成及毛细管柱气相色谱性能的研究

合成了一种新型的双苯甲酰胺冠醚固定相:(1S,2S)-1-(对苯甲酰胺基)苯基-2-苯甲酰胺基-16-冠-5,其结构经红外光谱、核磁共振、质谱及元素分析数据证实。考察了这种固定相的柱效、热稳定性、极性及选择性等色谱特性。该类固定相对极性位置异构体分离效果良好。由于冠醚上引入苯甲酰胺取代基,因而对苯胺类及不经衍生化的碱性化合物能特殊选择性地分离。