亲水反相C18键合固定相的制备及分离性能

针对常规C18反相色谱柱无法满足在高水相及纯水流动相条件下的液相色谱分析,采用混合键合的方式得到一种新型亲水反相色谱固定相,通过元素分析及红外分析对固定相进行了物理表征;以尿苷为试样、纯水为流动相进行色谱分析,并按照2010版中国药典中对头孢他啶进行分析。结果表明,此种新型固定相在亲水条件下分离度和理论塔板数方面明显优于常规反相色谱柱。     

新型离子液体气相色谱固定相研究

合成了一种用作新型气相色谱固定相的室温离子液体[C7H17NO] [(CF3SO2)2N]-,并考察其色谱性能。该固定相具有较好的成膜性、较高的柱效、较强的极性,对正构烷烃、芳香族化合物以及一些位置异构体具有良好的分离效果。     

新型气相色谱固定相十二烷基苯磺酸铝的研究

采用汞塞动态法制备了十二烷基苯磺酸铝玻璃毛细管柱柱1(固定液质量-体积浓度为13.6%,柱尺寸为30m×0.35mmi.d)和柱2(固定液浓度为100%,柱尺寸为39m×0.30mmi.d),所用溶剂是丙酮,并且对柱性能进行了考察。实验表明这种色谱固定相有较强的极性并对饱和烃、芳香烃、饱和酸、芳香酸、极性异构体等具有良好的分离能力,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定量分析。     

新型高效液相色谱固定相研究进展

对近几年来新型高效液相色谱固定相的研究与应用进行了综述。新型固定相的开发为拓宽HPLC的应用范围奠定了基础,并大大推动了HPLC的发展。     

高效液相色谱手性固定相拆分手性化合物

在纤维素衍生物手性固定相上直接拆分了3种手性化合物,并初步探讨了流动相组分———醇的种类及结构对拆分手性化合物的影响。     

Porapak QS固定相的色谱性能研究

针对国外Porapak QS的色谱性能进行了研究，测定了极性常数(麦氏常数)，提出在柱温170℃测定其常数的方法，测定了热分析曲线和17种物质的相对保留值；对柱温与保留值、关系进行了研究。     

新型刷型固定相的制备与评价

以硅胶为载体、β-(3,4-环氧环己烷)乙基三甲氧基硅烷为间隔臂、常用药物辛伐他汀为手性源,采用键合法制备出了新型刷型手性固定相(CSP),对安息香、钙离子拮抗剂和二苯丁酮等对映体进行了手性拆分测试,并以"三点作用"理论从流动相组成与分子结构等方面对其分离机理进行了探讨。良好的拆分结果证明,辛伐他汀以其多个手性中心特点在手性固定相的研制中具有较好的开发潜力。     

侧链和开链高分子冠醚色谱固定相的合成及其应用

介绍了侧链和开链高分子冠醚气相色谱固定相的应用进展。综述了以聚苯乙烯、聚硅氧烷和聚醚等为主链的侧链冠醚、开链冠醚和多足聚醚的合成方法,并提出用聚醚为主链的侧链冠醚和多足聚醚作为毛细管气相色谱固定相,可能有较好的应用前景。     

环糊精衍生物作高效毛细管气相色谱手性固定相的进展

着重介绍了近几年来报道的适用面较宽的一些环糊精（ＣＤｓ）手性固定相。它们包括亲油性的全烷基化的环糊精衍生物和部分烷基化部分酰基化的环糊精衍生物以及亲水性羟基烷基化的环糊精衍生物。简单述了这些ＣＤ衍生物的合成方法，分别讨论了它们在气相色谱手性分离中的作用。结果表明，ＣＤ衍生物可以使手性的环烷烃、烯烃、卤代烃、醇、醚、醛、酮、缩醛、（酮）、羟基酸（酯）、内酯、胺、氨基醇、氨基酸等达到基线分离。讨论了Ｃ     

高效液相色谱手性冠醚固定相的制备研究

冠醚是具有空腔且非常好的识别能力的大环聚醚化合物。系统地研究了将R-(3,3′-二溴基-1,1′-二萘基)-20-冠-6涂覆在粗制硅胶、精制硅胶、大孔硅胶、苯环修饰粗制硅胶、苯环修饰精制硅胶、苯环修饰大孔硅胶、十八烷基修饰粗制硅胶、十八烷基修饰精制硅胶、十八烷基修饰大孔硅胶、氨丙基修饰粗制硅胶表面制备10种不同支撑体的手性固定相用于苯甘氨酸和对羟基苯甘氨酸的拆分研究。研究表明大孔硅胶以及氨丙基修饰硅胶直接涂覆冠醚的柱皆不能拆分这两种氨基酸,另外硅胶表面是否修饰、以及修饰的基团对手性柱的分离能力具有影响,不同来源的硅胶也强烈地影响着手性柱的拆分效率。     

Supercritical Fluid Chromatography Applied to the Characterization of a Siloxane-Based Gas Chromatographic Stationary Phase

Abstract

Supercritical fluid chromatography using n-pentane as a mobile phase and Porasil C as a column packing was applied to the characterization of Dow-Corning 710 fluid, a commonly used gas chromatographic stationary phase. Under the experimental conditions, decomposition of the polymer was observed on columns of alumina, and derivatized Porasil packings were found to be unstable. Linear pressure programming variables were studied at 206 and 216°C by normalizing the total analysis time on a fixed length of column. A series of homologous polymer components was used to demonstrate the effects upon resolution of density-isotherm nonlinearity associated with the mobile phase. The results showed that optimal temperature conditions existed for the use of linear pressure programming, with the choice of temperature conditions dependent upon the molecular weight range. Operational guidelines are suggested. Mixed solvent behavior was investigated for this separation. The effect of changing the polarity of the mobile phase by adding 0 to 20% v/v isopropanol to n-pentane was studied under isothermal and isobaric conditions. The alcohol was shown to change adsorption characteristics and alter critical constants. The effect upon the critical constants appeared to conform to Kay's approximation. The results suggest that mixed solvents can be used to speed up separations for mixtures having components of widely different adsorption energies. The pseudocritical concept using Kay's approximation was tested for its qualitative ability to estimate state effects when solvents are mixed. The effect of temperature upon migration behavior was compared for equimolar amounts of isopropanol and methanol, each in n-pentane. Kay's approximation appeared to be useful for qualitative predictions regarding changes in critical pressure. However, an attempt to predict density isotherm behavior for 20 % isopropanol in n-pentane relative to pure n-pentane suggested that Kay's approximation may not be as useful for predicting criticla temperature effects.     

Chromatographic Evaluation of Octadecyl-Bonded SiO2/SiO2-Based Stationary Phase for Reversed-Phase High Performance Liquid Chromatography

A new type of octadecyl-bonded SiO₂/SiO₂ (ODSS) core–shell monodisperse silica spheres was prepared as a high performance liquid chromatography stationary phase. The chromatographic performance was evaluated and compared with totally porous octadecyl-bonded SiO₂. Various methods were used for characterization of the two column packings for reversed-phase chromatography in terms of permeability, hydrophobic selectivity, sensitivity, stability and hydrophobicity. The results showed that the ODSS-based stationary phase has enhanced permeability, good hydrophobic selectivity, high chemical stability and sensitivity. Acidic, basic and neutral aromatic compounds were separated on the two types of stationary phases. The ODSS-based stationary phase has good selectivity and gives symmetrical narrow peaks under reversed-phase conditions.     

疏水相互作用与亲水相互作用组合色谱纯化缩宫素

将疏水相互作用色谱与亲水相互作用色谱结合,建立了用于化学合成缩宫素粗品分离纯化的两步纯化工艺.先以纯水为流动相,采用Nylon6疏水相互作用色谱对粗品进行脱盐与富集,后以Superose12亲水相互作用色谱进行进一步纯化,两步纯化后,峰面积纯度达93.5%,提高了5.96倍,总回收率为50.1%,与用C18为介质的传统两步反相色谱纯化的结果相当.本方法有机溶剂用量仅为传统反相色谱的1/7,且两种介质都能耐受极端pH值清洗条件,重复利用率高.     

Preparation of Polymeric Stationary Phase for Use in Inverse Gas Chromatography

Abstract

The preparation of ground low‐density poly(ethylene) (LDPE), high‐density poly(ethylene) (HDPE), and poly(ethylene terephthalate) (PET) materials suitable for use by inverse gas chromatography (IGC) experiments is described. Materials prepared showed a smaller and more uniform particle size, 83–86 µm (200 mesh), than commercially available Chromosorb^® W solid chromatography support. In addition, the BET surface area of polymeric materials, 0.367–0.559 m²/cm³, was much greater than the surface area of 150‐ to 212‐µm‐diameter glass beads. The use of polymeric materials with uniform particle sizes and defined surface areas have several advantages over polymer coated Chromosorb^® W and glass beads in IGC experiments.     

GDX203色谱固定相的改性及在羰基合成醋酸中的应用

甲醇羰基化反应制醋酸,是一个重要的化学反应[1],无论在实验室或在工业生产上,其反应过程的监测均是以色谱为分析手段[2,3]。由于该反应产物的组分多(甲醇、水、碘甲烷、乙酸甲酯、醋酸),通常采用色谱程序升温的方法才可达到各组分的分离[4],这种方法由于存在分析周期长和由于反应物在色谱柱中的保留时间长而发生变化影响了定量的准确性的缺点,给对该反应进行的快速、准确的监测带来诸多不便。     

Discovery of a Novel Inhibitor of Human Purine Nucleoside Phosphorylase by a Simple Hydrophilic Interaction Liquid Chromatography Enzymatic Assay

Human purine nucleoside phosphorylase (HsPNP) belongs to the purine salvage pathway of nucleic acids. Genetic deficiency of this enzyme triggers apoptosis of activated T-cells due to the accumulation of deoxyguanosine triphosphate (dGTP). Therefore, potential chemotherapeutic applications of human PNP inhibitors include the treatment of T-cell leukemia, autoimmune diseases and transplant tissue rejection. In this report, we present the discovery of novel HsPNP inhibitors by coupling experimental and computational tools. A simple, inexpensive, direct and non-radioactive enzymatic assay coupled to hydrophilic interaction liquid chromatography and UV detection (LC-UV using HILIC as elution mode) was developed for screening HsPNP inhibitors. Enzymatic activity was assessed by monitoring the phosphorolysis of inosine (Ino) to hypoxanthine (Hpx) by LC-UV. A small library of 6- and 8-substituted nucleosides was synthesized and screened. The inhibition potency of the most promising compound, 8-aminoinosine ( 4 ), was quantified through K_i and IC₅₀ determinations. The effect of HsPNP inhibition was also evaluated in vitro through the study of cytotoxicity on human T-cell leukemia cells (CCRF-CEM). Docking studies were also carried out for the most potent compound, allowing further insights into the inhibitor interaction at the HsPNP active site. This study provides both new tools and a new lead for developing novel HsPNP inhibitors.     

新型两性离子粘土稳定剂的合成与性能评价

以环氧氯丙烷、二乙胺、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为聚合单体,以过硫酸钾—亚硫酸氢钠组成的氧化还原体系为引发剂,合成了一种新型两性离子粘土稳定剂,采用红外光谱对其结构进行了表征,用乌式粘度计测定其分子量,并通过一系列实验对其进行了性能评价。结果表明,该两性离子粘土稳定剂与盐水配伍性好,不仅用量省、耐洗刷、...     

离子液体作为气相色谱固定相的参数测定

将疏水性离子液体[BMIM]PF6用于气相色谱固定相中,检测分离环己烷、甲苯、邻二甲苯混合有机溶剂,并与邻苯二甲酸二壬酯填充柱对这3种物质的分离效果进行比较。实验结果表明：邻苯二甲酸二壬酯柱虽然也能将这3种物质分开,但各物质出峰太慢、保留时间长、峰高太低,而疏水性离子液体[BMIM]PF6柱对这3种物质有很好的分离效果,各物质保留时间缩短、峰高增强,由此得出离子液体作为气相色谱固定相对分离这类有机物的优势。