Extraction-Chromatographic Separation and Concentration of Phenol and Guaiacol with the Use of Organic Solvent Mixtures as Stationary Phases

Extraction-chromatographic concentration and separation of phenol and guaiacol was studied as influenced by the composition of binary tributyl phosphate-pentyl acetate, tributyl phosphate-dinonyl phthalate, tributyl phosphate-didecyl sebacate, and ternary tributyl phosphate-dicyclohexano-18-crown-6-toluene and tributyl phosphate-dicyclohexano-18-crown-6-chloroform stationary phases.     

氯丙基聚硅氧烷的合成及用作气相色谱固定相的研究

合成了几种新型的含氯丙基的取代聚硅氧烷,其热稳定性可达300～325℃,能较好地分离非极性和中等极性化合物。当固定相的苯基含量高达50％时,用8％的DCP能使其有效交联。     

气相色谱中特殊混合固定相的协同效应研究

在气相色谱中,组份在混合固定液上的保留值具有加和性［１～３］．我们在研究一些特殊选择性固定液进行混合固定相保留行为时,发现存在一定的协同效应［４,５］．本文在以全戊基β－环糊精／ＴｌＮＯ３、有机皂土－３４／ＡｇＮＯ３、全戊基β－环糊精／ＡｇＮＯ３为混...     

改性的配体交换型手性固定相的合成及应用

通过在巯丙基硅胶表面引入苯乙烯长链,再加入甲基丙烯酸缩水甘油酯在聚苯乙烯链端进行延长,用L-脯氨酸和L-羟脯氨酸进行修饰的方法合成了两种聚合物型配体交换型手性固定相(CSPⅣ和CSPⅤ),并采用6种氨基酸对映体考察了合成固定相的色谱拆分效果。结果表明,除DL-脯氨酸外,其余氨基酸对映体均具有相同的出峰顺序,即D-异构体优先出峰。与不含聚苯乙烯单元的配体交换型手性固定相相比,CSPⅣ和CSPⅤ具有更小的保留因子,更好的对映体选择性和更高的分离度。     

多糖类手性固定相在色谱中的应用

手性色谱技术是最重要的手性分离方法之一,它不仅可以快速地分析对映体纯度,也可以用于大量制备光学异构体。设计和发展高效的固定相是手性色谱技术的核心。在诸多的手性固定相中,多糖类手性固定相因品种繁多、耐用而被广泛应用。本文综述了多糖类手性固定相在高效液相色谱、模拟移动床色谱、超临界流体色谱及膜分离中的应用。共引用文献52篇。     

Elevated Temperature Separations on Hybrid Stationary Phases with Low Proportions of Organic Modifier in the Eluent

The properties of two thermally stable organic/inorganic hybrid columns, XTerra MS C₁₈ and XTerra phenyl were examined at elevated temperatures, using a number of test compounds, including acetophenone derivatives and phenols, with 5 and 10% methanol in water as the mobile phases. The thermodynamics of the separations were examined. The study demonstrated that a low proportion of organic modifier and moderate temperatures gave similar separations to higher temperature with superheated water, potentially reducing stress on the column and analytes.     

Prediction,optimization of separation,and identification of unknown compounds in capillary gas chromatography

A procedure for the identification and separation of unknown compounds by capillary gas chromatography is described. The procedure involves a live retention time database and optimization of the separation. After initial chromatography of the sample, a rough search lists all the possible compounds it might contain and the analyst then uses his experience to discard those compounds in the list which are unlikely to be present. The multi-component separation is then optimized over the whole range of defined starting temperatures and programming rates, in order to produce the best possible separation of the sample components, and the chromatography repeated using the results obtained from the optimization procedure. Further search operations within a given search window will then report the compound names, and related information, for each peak. Since the identification operation is performed at least twice during the procedure, and the optimization of the separation assists the identification by separating possibly overlapped peaks, the confidence of the qualitative analysis is higher than may be obtained using standards alone. If the reproducibility of isothermal indices measured on columns could be guaranteed, this procedure could be used instead of performing chromatography on standards of the compounds contained in the database, regardless of changes in column dimensions, phase ratio, and operating conditions in temperature programmed analysis.     

不同极性固定相上醇色谱保留指数的预测

采用拓扑指数(mQ)、定位基参数(SOX)及固定液极性值(CP)与脂肪醇在6种固定相上的气相色谱保留指数值(RI)进行了相关分析,发现RI与上述参数间存在良好的相关性,其关系可表示为:RI=158·384 57·7220Q-12·0491Q 5·720SOX 5·756CP R=0·9913继以留一法(Leave-one-out,LOO)进行交互检验,相关系数RCV=0·9909。说明所建定量结构-保留关系(QSRR)模型具有良好的稳定性和预测能力,较好地揭示了脂肪醇类物质在不同固定相上气相色谱保留指数的变化规律。     

磷酰胆碱色谱固定相的制备及其在分离生物大分子中的应用

以三氯氧磷、氯化胆碱和甲基丙烯酸-2-羟乙酯(HEMA)为原料合成了含磷酰胆碱的单体2-甲基丙烯酰氧乙基磷酰胆碱(MPC). 在硅胶表面嫁接聚合MPC, 得到磷酰胆碱两性离子交换色谱填料. 研究了该填料对标准蛋白的分离性能及pH对蛋白质保留的影响. 结果表明, 该填料对溶菌酶和牛血清白蛋白的动态吸附容量分别为13.8和18.7 mg/g, 其基质磷酰胆碱色谱固定相可同时基线分离两种酸性和两种碱性蛋白.     

亲水作用色谱固定相的发展及应用

亲水作用色谱作为一种高效液相色谱技术,在强极性和离子型化合物如氨基酸、碳水化合物和多肽等的分离分析中发挥着重要作用。作为色谱技术的核心,亲水作用色谱材料的发展直接影响着色谱分离的选择性和分离效率,制约着亲水作用色谱的应用和推广。目前商品化和学术报道的亲水作用色谱材料种类繁多,键合相结构丰富。本文从色谱材料结构出发,综述了近5年内基于硅胶基质的亲水作用色谱固定相,包括纯硅胶、氨基、氰基、二醇基、酰胺型、聚（琥珀酰亚胺）型、糖型和两性离子型键合相的发展及其在极性药物、蛋白质组学、代谢组学等方面的典型应用。同时简要介绍了近年来亲水作用色谱的色谱评价研究。     

Modification of Selectivity in Reversed-Phase Liquid Chromatography of Polycyclic Aromatic Hydrocarbons Using Mixed Stationary Phases

Abstract

Monomeric and polymeric C₁₈ materials provide significantly different selectivities for polycyclic aromatic hydrocarbons (PAH) in reversed-phase liquid chromatography. Selectivity factors vary in a regular manner with respect to surface concentration of C₁₈ groups on different C₁₈ columns. In this study, we investigated the feasibility of “customizing” a C₁₈ column to provide an intermediate selectivity by mixing 5-μm polymeric C₁₈ material from two different lots with high and low C₁₈ surface concentrations. Polymeric C₁₈ materials from different production lots were mixed in ratios of 30/70, 50/50, and 70/30 (w/w). Selectivity factors for these columns were found to be similar to those predicted by the linear addition of the selectivities of the two individual phases. The PAH selectivities on these mixed columns were also found to be comparable to data obtained from coupled short columns of appropriate lengths each containing one of these different C₁₈ materials. These studies indicate that columns of specific selectivity can be prepared by either mixing two different C₁₈ materials or by coupling columns containing each of these different phases. The use of mixed phase columns is illustrated for the analysis of a fraction containing five condensed ring PAH isomers (molecular weight 278) isolated from an air particulate sample.     

乙二醇-磷霉素改性氧化锆色谱固定相的制备及其在蛋白质分离中的应用

合成了分离蛋白质的乙二醇-磷霉素钠改性氧化锆高效液相色谱固定相, 通过漫反射红外光谱、元素分析等分析方法对该固定相进行了表征. 以溶菌酶、核糖核酸酶A、细胞色素C和糜蛋白酶四种标准碱性蛋白质为探针, 系统地考察了固定相的疏水相互作用色谱性能. 结果表明, 乙二醇-磷霉素改性氧化锆固定相对蛋白质有一定的保留, 表现出较高的分离选择性.     

环糊精衍生物作为气相色谱固定相的发展及应用

从环糊精及其衍生物作为气相色的分离机理出发介绍了影响这固定相的因素及其分离应用的近期发展,共评述56篇文章。     

High-temperature separation with polymer-coated fiber in packed capillary gas chromatography

High-temperature gas chromatographic separation of several synthetic polymer mixtures with Dexsil-coated fiber-packed columns was studied. A bundle of heat-resistant filaments, Zylon, was longitudinally packed into a short metal capillary, followed by the conventional coating process with Dexsil 300 material. Prior to the packing process the metal capillary was deactivated by the formation of a silica layer. The typical size of the resulting column was 0.3-mm i.d., 0.5-mm o.d., 1-m length, and packed with about 170 filaments of the Dexsil-coated Zylon. The column temperature could be elevated up to 450°C owing to the good thermal stability of the fiber, Dexsil coating, and metal capillary; furthermore, this allowed the separation of low-volatile compounds to be studied.     

气相色谱固定相研究进展

介绍了气相色谱固定相的研究进展，重点对各种冠醚固定相的特征，应用和分离机理进行了评述。     

A New Application of McReynolds Constants to the Characterization of the Chromatographic Properties of Stationary Phases

An algorithm was proposed for comparing the McReynolds constants of new gas-chromatographic stationary phases with data for not only well-known individual substances but also their binary combinations. It was found that, in most cases, sets of these parameters for the chromatographic properties of new stationary phases are inconsistent with the data for a restricted set of previously characterized phases; however, they are consistent with the properties of phase combinations. This can be interpreted in terms of the absence of specific properties. Exceptions were found only among stationary phases bearing some specific molecular fragments (such as nitro groups) and individual crown ethers.     

Multivariate curve resolution combined with gas chromatography to enhance analytical separation in complex samples: A review

This review describes the major advantages and pitfalls of iterative and non-iterative multivariate curve resolution (MCR) methods combined with gas chromatography (GC) data using literature published since 2000 and highlighting the most important combinations of GC coupled to mass spectrometry (GC–MS) and comprehensive two-dimensional gas chromatography with flame ionization detection (GC × GC-FID) and coupled to mass spectrometry (GC × GC–MS). In addition, a brief summary of some pre-processing strategies will be discussed to correct common issues in GC, such as retention time shifts and baseline/background contributions. Additionally, algorithms such as evolving factor analysis (EFA), heuristic evolving latent projection (HELP), subwindow factor analysis (SFA), multivariate curve resolution-alternating least squares (MCR-ALS), positive matrix factorization (PMF), iterative target transformation factor analysis (ITTFA) and orthogonal projection resolution (OPR) will be described in this paper. Even more, examples of applications to food chemistry, lipidomics and medicinal chemistry, as well as in essential oil research, will be shown. Lastly, a brief illustration of the MCR method hierarchy will also be presented.     

Stationary phase properties of the organic molten salt ethylpyridinium bromide in gas chromatography

Summary The organic molten salt, 1-ethylpyridinium bromide, is suitable for use as a stationary phase in gas chromatography. It has a usable liquid temperature range of 110 to 160°C. It undergoes a single phase transition at 110°C which corresponds to the bulk melting point. Below the melting point the phase may be used as a selective adsorbent, although column efficiency and peak symmetry deteriorate as the temperature is lowered from the melting point. Above the melting point, ethylpyridinium bromide can be used to separate a wide variety of organic compounds retaining strongly those compounds possessing large dipole or hydrogen bonding functional groups.     

气相色谱分离多环芳香环境污染物用固定相的应用进展

综述了几种气相色谱固定相包括聚硅氧烷、液晶、冠醚、环糊精、离子液体及纤维填充固定相,在分离多环芳香烃(PAHs)、多环芳香化合物(PACs)及多氯联苯(PCBs)等环境污染物中的应用进展,展望了此类固定相的应用前景(引用文献64篇)。