葡萄糖苷特异性固相萃取固定相的合成、表征及应用

以马来酰亚胺基修饰凝胶载体,通过β-葡萄糖胺和2-亚氨基硫代烷盐酸盐将作为配基的β-葡萄糖脒连接到载体上,合成了一种葡萄糖苷特异性固相萃取固定相,并对其固相萃取性能进行了表征.该固定相对葡萄糖苷具有特异性识别,并成功用于固相萃取分离葡萄糖苷.     

Immobilized stationary phases on the basis of polyethylene glycol

The preparation of the immobilized stationary phase based on Carbowax 20 M is described. Bifunctional isocyanates were used for cross-linking. The properties of the prepared stationary phase were studied.     

离子色谱固定相最新进展

介绍离子色谱固定相的最新研究进展。离子色谱固定相在多种类型、含多种功能基和高交换容量固定相,羟基选择性固定相,高效的涂覆型固定相,可变交换容量的固定相,静电离子和仿生离子固定相,整体式固定相。以及芯片式固定相等方面均有所发展。     

万古霉素键合固定相的分离性能

万古霉素作为一种大环抗生素,具有复杂的分子结构。在充分考虑万古霉素分子结构特征的情况下,采用戊二醛间隔臂法制备了万古霉素键合固定相,在反相、亲水、离子交换等分离模式下研究了其色谱分离性能。结果表明,当流动相中有机调节剂含量较低时,该色谱柱表现出典型的反相色谱分离模式特征;随着有机调节剂含量的增加,逐渐转变成亲水模式,分离特性发生明显改变。由于万古霉素分子结构中含有可以解离的氨基,因此该固定相也能够用于阴离子交换模式下的分析方法的发展。分别在反相、亲水和阴离子交换模式下,将其应用于扑尔敏等多种非对映体药物和新型甜味剂甜菊糖的高效液相色谱分离;仅通过改变分离条件,即可在3种不同分离模式下完成分离。这些结果可以为新型色谱固定相的设计,以及发展采用特殊结构改性基团的色谱固定相在相应分离模式下的分析方法提供指导。     

反相液相色谱法分离2-(4-羟基苯氧基)丙酸酯对映体

合成了三-(4-甲基苯甲酸)纤维素酯(MCTB)手性固定相，用反相高效液相色谱法在该手性固定相上对2-(4-羟基苯氧基)丙酸酯对映体进行拆分．实验结果表明，在三-(4-甲基苯甲酸)纤维素酯手性固定相上，以甲醇与水的体积分数为75：25做流动相能较好的拆分2-(4-羟基苯氧基)丙酸甲酯、乙酯和丁酯对映体，其分离因子分别为1．38、1．49、0．98；同时还发现2-(4-羟基苯氧基)丙酸酯中酯基团的大小对其对映体的分离也有明显的影响，其中以乙酯的拆分效果最佳。     

新型杯[4]芳烃高效液相色谱固定相的制备及表征

合成了一种新型的杯[4]芳烃高效液相色谱键合固定相,考察了它的反相色谱行为．通过对多环芳烃、二取代苯的位置异构体、苯甲酸酯和邻苯二甲酸酯的分离,发现该键合相具有显著的反相特征,对位置异构体具有很高的识别能力,其分离明显优于C18柱,并讨论了可能的分离机理．     

The effect of stationary phase on lipophilicity determination of beta-blockers using reverse-phase chromatographic systems

Evaluation of lipophilicity parameters for basic compounds using different chromatographic stationary phases is presented. An HPLC method for determination of lipophilic molecule-stationary phase interactions was based on gradient analysis. Differences in correlation between the lipophilicity of compounds and experimental chromatographic results obtained in pseudo-membrane systems showed a strong influence of stationary phase structure and physico-chemical properties. beta-Blocker drugs with varying lipophilicity and bio-activity were chosen as test compounds. The stationary phases used for the study were monolithic rod-structure C18 and silica gel octadecyl phase SG-C18 as reference material. The second group was silica gel-based polar-embedded alkylamide and cholesterolic phases. The mobile phase was composed of acetonitrile or methanol with ammonium acetate, and a linear gradient of methanol and acetonitrile in mobile phase was performed. A linear correlation of plots of log k(g) = f(log P) was observed, especially for polar-embedded phases, and this allowed log P(HPLC) to be calculated. The behavior of stationary phases in methanol and acetonitrile buffer showed differences between obtained log P(HPLC) values.     

混合色谱填料的研究进展

随着科学技术的发展,人们需要分离分析的样品越来越复杂,尤其是多肽、蛋白质类生物样品的复杂性使得单一模式色谱难以满足分离分析的要求。混合模式色谱因其独特的分离性能,可以在一次分离中获得与多维色谱相当的分离效果,而且可以避免多维色谱系统结构复杂、流动相兼容性差、分析时间长等问题,成为近年来的研究热点之一。混合模式色谱的研究重点是色谱固定相的设计与开发。混合模式色谱固定相包括反相/离子交换混合固定相、反相/亲水混合固定相、亲水/离子交换混合固定相、两性离子交换混合固定相及三相混合固定相。本文综述了近年来混合模式色谱填料的研究及应用进展,并对混合模式色谱及固定相的发展前景进行了展望。     

气相色谱键合固定相的制备及农药残留测定的应用研究

本文采用热反应键合法,将ＰＥＧ－２０Ｍ与４０５白色硅藻上载体进行热键合制备气相色谱键合固定相。用ＴＧ－ＤＴＡ法对固定相的键合量及温度特性进行研究,结果表明,键保固定相具有较好的色谱性能,能有效地应用于食品及农产品中多种有机磷类农药、氨基在农药以及拟除虫菊酯类农药残留量的分离测定。     

Solute retention in the stationary phase of a liquid-solid chromatographic system

Summary Utilizing the UNIFAC group model of activity coefficients the retention behaviour of a solute in the stationary phase of a liquid-solid chromatographic system is studied. By comparison of experimentally observed capacity ratios and calculated activity coefficients of solutes in the mobile phase, varying the concentration of a polar moderator, it is shown that the calculated activity coefficients in the stationary phase fit very well the equation formally identical with the Langmuir function. Comparison of activity coefficients in the mobile and the stationary phase proves equivalence between the solvent interaction and the competition theory.     

C18-磺酸基双改性液相色谱固定相的制备与评价

以十八烷基三氯硅烷和3-巯丙基三甲氧基硅烷为改性剂,采用一锅法对硅胶表面加以修饰,进一步将巯基氧化制备成C18-磺酸基双改性液相色谱固定相.在优化的反应条件下得到了十八烷基和磺酸基摩尔比为3∶7的固定相,分别采用扫描电镜、元素分析、红外光谱对固定相的形貌和特征加以表征.针对制备的固定相,在不同的分离模式下,系统考察其色谱分离性能.在反相色谱模式下,成功分离了5种烷基苯化合物;在亲水模式下,分离了3种核苷;进一步应用于牛血清白蛋白酶解产物的分离,得到了较好的结果.实验结果表明,制备的混合模式固定相同时具有多种分离机理,在分离复杂样品、调整选择性方面具有潜在的优势.     

十二烷基键合氧化锆固定相的制备与性能评价

以自制5μm球形氧化锆为基质，制备了十二烷基键合氧化锆HPLC固定相，考察了正烷基取代苯、稠环芳烃、苯胺及吡啶衍生物、苯酚和硝基苯酚异构体等不同性质化合物在固定相上的保留行为，并与十二烷基键合硅胶固定相进行了比较。结果表明：中性和碱性化合物在固定相上主要为反相色谱保留机理；酸性化合物在固定相上以反相色谱保留机理为主，但是氧化锆表面的Lewis酸性中心对溶质也存在一定程度吸附作用，导致色谱峰拖尾。     

Retention mechanism of peptides on a stationary phase embedded with a quaternary ammonium group: A liquid chromatography study

We investigated the mechanisms involved in the retention of various peptides on a stationary phase embedded with a quaternary ammonium group (BS C23), by high-performance liquid chromatography. This was compared with peptide retention on a conventional reversed-phase C18 (RP C18) column under isocratic conditions, to understand better the various mechanisms involved. Chromatographic characterization of the two stationary phases with “model” compounds showed that BS C23 is less hydrophobic than RP C18 and induces electrostatic interaction (attraction or repulsion) with ionized compounds. If reversed-phase partitioning was the predominant retention phenomenon, for both stationary phases, the retention mechanisms in BS C23 provided different selectivity to that of RP C18. Electrostatic attraction or repulsion was clearly observed between peptides and the permanent positively charged group embedded in BS C23 depending on the pH. For most of the peptides, a weak anion-exchange mechanism was observed on the quaternary ammonium-embedded stationary phase if mobile phases at neutral pH and low ionic strengths were employed.     

多糖衍生物类固定相在高效液相色谱手性分离中的应用进展

评述了多糖衍生物手性固定相在高效液相色谱手性分离中的应用进展，介绍了多糖衍生物手性固定相的主要类型，阐述了手性拆分机理和影响手性拆分的因素，引用文献66篇。     

Synthesis and Evaluation of a Synthetic Polymeric Chiral Stationary Phase for LC Based on the N, N′-[(1R,2R)-1,2-Diphenyl-1,2-Ethanediyl]bis-2-Propenamide Monomer

A synthetic polymeric chiral stationary phase for liquid chromatography based on N, N′-[(1R,2R)-1,2-diphenyl-1,2-ethanediyl]bis-2-propenamide monomer was prepared via a simple solution initiated radical polymerization. This stable chiral stationary phase showed enantioselectivities for a large number of racemates in polar organic and normal phase modes and high sample loading ability. However, none of the generated data has been optimized in terms of column performance. Different enantioselectivities were observed on this new chiral stationary phase compared with the commercial polymeric chiral stationary phase based on N-(2-acryloylamino-(1R,2R)-cyclohexyl)-acrylamine monomer. Consequently, these two chiral stationary phases are considered complementary to one another. Furthermore they utilize the same mobile phase and optimization procedures. This polymeric chiral stationary phase appears to be useful for preparative separations since high amounts of analyte can be injected without loosing enantioselectivity.     

GDX系列固定相保留行为与柱温关系的考察

 在测定了 GDX-1 0 1～GDX-1 0 5系列固定相的相对麦氏常数的基础上 ,考察了柱温 1 40～ 2 2 0℃时 ,GDX-1 0 1及 GDX-1 0 3两种固定相的相对麦氏常数随温度改变的变化情况。发现 1 80℃时 ,ΔI-θc曲线发生了弯曲 ,认为此时固定相的保留行为也随之发生了一定的变化。     

手性有机磷化合物液相拆分的研究进展

 综述了近年来手性有机磷化合物液相拆分的研究进展。对间接拆分和直接拆分法,特别是各类手性固定相法在拆分有机磷化合物中的应用作了介绍,探讨了相应的拆分机理。85篇。     

Evaporation of the liquid stationary phase in gas chromatography

Summary The theory of the evaporation of the liquid stationary phase is elaborated and experimentally verified. On the basis of this theory the role played by the losses in the amount of liquid phase present is quantitatively determined. General techniques are examined which minimize the losses; these techniques are based on saturating the incoming carrier gas with liquid phase vapours and raising the pressure of the carrier gas in the column, e.g. by connecting a capillary to the column outlet in order to offer resistance to the gas flow. The application of these techniques ensures stable performance of the gas chromatographic columns using a volatile liquid phase.     

三唑类杀菌剂己唑醇外消旋体的手性拆分研究

以正己烷为流动相，添加一定比例的异丙醇作为改性剂，在纤维素—三(3，5—二甲基苯基氨基甲酸酯)(CDMPC)手性固定相上，实现了对己唑醇光学异构体的高效液相色谱直接拆分，研究了流动相中异丙醇的比例对分离效果的影响，优化了色谱拆分条件，进行了机理的初步探讨。     

Synergistic effect of resorcarene and cyclodextrin mixed stationary phase in gas chromatography

Summary A new resorcarene derivatives, ethylhexylresorcarene, was synthesized and used as stationary phase in opentubular (capillary) columns. It was combined with heptakis(2,6-di-O-pentyl-3-O-trifluoroacetyl)-β-CD and coated on fused-silica capillary tubes. By studying the chromatographic properties of the mixed stationary phase and its selectivity for different isomers, as well as comparing with the resorcarene and the CD used as individual stationary phases, a synergistic effect was observed on the mixed stationary phase.