Novel cyclodextrin chiral stationary phases for high performance liquid chromatography enantioseparation: Effect of cyclodextrin type

Three novel chiral stationary phases (CSPs) were prepared by regioselective chemical immobilization of mono(6^A-N-allylamino-6^A-deoxy)perphenylcarbamoylated (PICD) α-, β-, and γ-cyclodextrins (CDs) onto silica support via hydrosilylation. Their enantioseparation properties in high performance liquid chromatography (HPLC) were evaluated with a large spectrum of racemates including flavanone compounds, β-adrenergic blockers, amines and non-protolytic compounds. The effect of CD's cavity size on enantioseparation abilities was studied and discussed. The results indicated that CD's surface loading at silica support played an important role in the enantioseparation on these CSPs under normal-phase conditions while inclusion phenomena contributed the major driving force under reverse-phase conditions. As expected, α-PICD demonstrated the best resolutions towards flavonone and most aromatic alcohols under normal-phase conditions with the highest surface loading; while Fujimura's competitive inclusion model can be applied to explain the better enantioseparations towards β-adrenergic blockers, amines and non-protolytic compounds with α- and β-PICD CSPs. γ-PICD CSP showed superior enantioseparation ability for sterically encumbered analytes like flavanone compounds under both normal-phase and reversed phase conditions.     

超临界流体色谱与高效液相色谱分离手性化合物的比较

超临界流体色谱(SFC)分离具有速度快、分离效率高、溶剂消耗少等优点,近年来在手性化合物的分离分析中得到诸多应用。本文对比研究了涂覆型多糖手性色谱柱在SFC和高效液相色谱(HPLC)上拆分24种手性化合物的差异。通过比较这些化合物在色谱柱上的保留时间和选择因子等发现多数化合物在SFC上的分离效率要高于其在HPLC上的分离效率,但HPLC对轴手性化合物的分离效率要优于SFC。SFC和HPLC的分离表现出一定的互补性,随着苯环侧链烷基的碳数增加,化合物在SFC上的保留逐渐增强,而在HPLC的保留却逐渐减弱。叶菌唑在使用SFC和HPLC分析时出现了洗脱顺序反转的现象。这些结果为SFC手性拆分提供了参考。     

含极性基团的硅质高效液相色谱固定相

介绍了含极性基团硅质高效液相色谱固定相的研究进展,对反相固定相的合成、极性基团作用机理和色谱性质方面作了评述,对手性分离固定相和高效离子色谱固定相方面的进展也作了简单综述。     

高效液相色谱法测定胭脂红酸的研究

研究了以反相C18柱,V(甲醇)∶V(乙腈)∶V(pH 2.8 H3PO4)=12∶8∶80混合溶液为流动相,对胭脂红酸进行高效液相色谱分析的方法。胭脂红酸在2.5~40μg/mL范围内的吸光度线性相关系数达0.9998,方法回收率在98.2%~101.1%,相对标准偏差为0.78%~1.2%,已用于样品中胭脂红酸的测定。     

Preparation and evaluation of phenylpropyl-treated porous glasses for high performance liquid chromatography

The retention and selectivity behavior of some aromatic hydrocarbons and alkylbenzenes on phenyl- or phenylpropyl-modified glasses have been studied by high performance liquid chromatography. From elemental analysis data for carbon, the maximum number of accessible phenyl or phenylpropyl surface groups per 100 Ų of glass (mean pore diameter, 157 Å; specific surface area, 213 m²/g) in the phenyl and phenylpropyl modified glasses were calculated to be 1.93 and 1.97, respectively. Using 60:40 methanol-water mixtures as eluents, the aromatic hydrocarbons or alkylbenzenes were separated on the glasses studied, but with different degrees of resolution.     

HPLC of synthetic polymers

Summary Statistical copolymers of styrene and acrylonitrile have been separated by high performance precipitation chromatography according to the increase in acrylonitrile content. The separation mechanism was strongly depending on the combination of stationary phase and eluent composition. By applying a typical normal phase gradient from n-heptane (precipitation) to dichloromethane the polymers were adsorbed, after dissolution of the polar groups of the stationary phases. The elution curves became broader with increasing acrylonitrile content of the polymer. By the addition of 20% methanol to the dichloromethane the adsorption could be minimized and copolymer elution was dependent solely on solubility and independent of stationary phase polarity. Separation according to chemical composition was also possible without precipitation with a large pore silica and a normal phase gradient from dichloromethane to the same eluent containing 2.75% methanol.Part I see reference 19     

液相色谱分析AEE788对映体纯度

在Chiralcel OD-H色谱柱上,采用正己烷与异丙醇或乙醇为流动相,对AEE788对映体进行了拆分,考察了流动相组成、柱温和流速等条件对拆分效果的影响。结果表明,AEE788对映体在正己烷-异丙醇-二乙胺(75:25:0.15,V/V/V)为流动相、柱温25℃、流速1.0 mL/min条件下,分离度为1.85,分析时间小于12 min。该分析方法的建立对药物AEE788不对称反应研究、分析/分离方法的开发及其生产过程的质量监控都具有非常重要的意义。     

Separation of enantiomers of new psychoactive substances by high‐performance liquid chromatography

New psychoactive substances are defined as compounds with consciousness‐changing effects and have been developed simultaneously with classical drugs. They arise through structural modifications of illegal substances and are mainly produced to circumvent laws. Availability is simple, since new psychoactive substances can be purchased from the Internet. Among them many chemical drug compound classes are chiral and thus the two resulting enantiomers can differ in their effects. The aim of this study is to develop a suitable chiral high‐performance liquid chromatography separation method for a broad spectrum of new psychoactive substances using cellulose tris(3,5‐dichlorophenylcarbamate) as a chiral selector. Experiments were performed by high‐performance liquid chromatography in normal‐phase mode under isocratic conditions using ultraviolet detection. Direct separation was carried out on a high‐performance liquid chromatography column (Lux® i‐Cellulose‐5, 3.5 μm, Phenomenex®), available since 2016. Excellent separation results were obtained for cathinones. After further optimization, even 47 instead of 39 out of 52 cathinones showed baseline separation. For amphetamine derivatives, satisfactory results were not achieved. Further, new psychoactive substances from other compound classes such as benzofuranes, thiophenes, phenidines, phenidates, morpholines, and ketamines were partially resolved, depending on the polarity and degree of substitution. All analytes, which were mainly purchased from the Internet, were proven to be traded as racemates.     

Full use of the liquid nature of the stationary phase: The development of elution‐extrusion counter current chromatography

Elution‐extrusion counter current chromatography extrudes the most solute retained in the column with the highest possible peak resolution. It can greatly improve the hydrophobic window. In recent years, elution‐extrusion counter current chromatography has received extensive attention in the separation of complex samples. This article first reviews the development and application of elution‐extrusion counter current chromatography, including its origin, mechanism, advantages and disadvantages, and some representative applications. At the same time, this review also shared our visions and ideas on how to improve the elution‐extrusion mode. This article aims to provide certain reference for the research of this technology.     

高效液相色谱法测定保健食品中的大豆异黄酮

建立了一种测定保健食品中大豆异黄酮的高效液相色谱分析方法,该方法可以使常见的大豆异黄酮6种主要成分大豆甙、黄豆甙、染料木甙、大豆甙元、黄豆黄素、染料木素得以分离和检测。采用乙腈-磷酸水溶液(pH2.8)作流动相,梯度洗脱,Venusil MP-C18色谱柱(150 mm×4.6 mmi.d.,5μm),流速为1.0 mL/min,紫外检测器,检测波长254 nm。结果表明各组分线性关系良好,相关系数R2为0.9991~0.9998,加标回收率在87%~106.9%,相对标准偏差均小于2%。检出限0.25~0.48μg/mL,该方法可同时测定大豆异黄酮的6种成分。     

用HPLC-模式识别技术表征云南烤烟烟叶的颜色相似性

对烟草等天然产物的质量评价可通过发展能对色谱图轮廓实施数学处理的化学计量学得到解决,如模式识别技术。颜色和香气是反映烟叶质量的两个重要特征,分别与烟叶中多酚类物质和精油成分有关^[6-11]。文献^[4,5]副基于烟草中多酚类物质高效液相色谱图轮廓的模式识别．评价了几种保加利亚烤烟和香料烟烟叶的颜色性能。     

烟草各部位中茄尼醇含量分布研究

采用Kromsil ODS-1色谱柱,V(甲醇)∶V(乙醇)=55∶45混合液为流动相,在紫外检测波长设定为211 nm的高效液相色谱条件下测定了烟草中各部位提取物中的茄尼醇,其中烟叶中茄尼醇的质量分数为0.45%,其他部位茄尼醇的质量分数为:烟梗0.037%,烟茎0.0037%,烟根0.0037%,其中烟叶中的茄尼醇量最高,具有提取价值.     

高效液相色谱法同时测定化妆品中的10种合成着色剂

建立了高效液相色谱同时测定化妆品中颜料橙5、酸性黄36、颜料红53、酸性紫49、罗丹明B、溶剂蓝35、苏丹红Ⅱ、苏丹红Ⅳ、分散黄3和颜料红57等10种合成着色剂的方法。用四氢呋喃(THF)、二甲基亚砜(DMSO)和甲醇对样品进行分步超声辅助萃取、离心净化后,在Eclipse XDB-C₁₈(150 mm×4.6 mm, 5 μm)色谱柱上分离。用乙腈-0.02 mol/L乙酸铵溶液(用乙酸调pH至4.60)作为流动相进行梯度洗脱,二极管阵列检测器(DAD)检测。在0.5~20.0 mg/L范围内,10种着色剂的峰面积与质量浓度呈线性关系,相关系数(r)大于0.999;定量限(LOQ)为10~20 mg/kg。在3个添加水平的回收率均在92.9%~108.8%之间,相对标准偏差(RSD)为0.5%~6.1%(n=6)。该方法简便、快速、灵敏,适合油状、粉状和膏状化妆品中禁限用着色剂的定量检测。     

HPLC determination of carotenoids in human serum by gradient elution technique

Summary Polarities of the carotenoids in human serum are very different; many nonpolar carotenoid hydrocarbons (e.g. -carotene, lycopene) and highly polar hydroxycarotenoids (e. g. -cryptoxanthin, zeaxanthin, lutein) can be found among them.Gradient elution chromatography was used for the separation of -carotene, lycopene, -cryptoxanthin, lutein and zeaxanthin in serum samples applying amino and cyano packings (Chromsil-NH₂, Chromsil-CN). The effects of different stationary phases on the selectivity were compared. The method is particularly suitable for the direct determination of serum levels of carotenoid in serum extracts.     

高效液相色谱法测定烟火药剂中的没食子酸

建立了烟火药剂中没食子酸的高效液相色谱检测方法。采用ZorbaxEclipse XDB-C18色谱柱(4.6×150 mm)分离,以甲醇-0.1%冰乙酸水溶液为流动相,梯度洗脱,流速1.0 mL/min;测定温度为25℃;采用紫外检测器检测,检测波长为274 nm。没食子酸的质量浓度在0.5~20μg/mL时与色谱峰面积之间线性关系良好(相关系数r=0.9999);对烟火药剂样品进行3个不同浓度水平的添加回收,回收率为90.8%~100.2%,相对标准偏差(RSD)为1.2%~6.4%。     

Separation of Dietary Folates by Gradient Reversed-Phase HPLC: Comparison of Alternative and Conventional Silica-Based Stationary Phases

A study of ten silica-based stationary phases and gradient elution conditions to separate dietary folates by reversed-phase HPLC was performed. Alkyl-bonded stationary phases (both conventional and alternative) were found to be the most promising for the separation of different folate monoglutamates in terms of selectivity and peak shape. These phases were better than phenyl-bonded phases which lacked selectivity when separating 10-formyl-folic acid and 5-formyl-tetrahydrofolate. Polar-bonded (cyano) stationary phase showed similar retention characteristics as the conventional alkyl-bonded phases, but ranked below those in terms of peak shape. Overall, alternative stationary phases exhibited slightly higher retention of late-eluted folates and greater retention variability for early-eluting tetrahydrofolate and 5-methyl-tetrahydrofolate. Best selectivity was achieved on alternative polar endcapped Aquasil C₁₈ followed by conventional Synergy MAX C₁₂ and Genesis C₁₈ stationary phases.     

高效液相色谱法测定化妆品中氯噻酮和吩噻嗪

建立了反相高效液相色谱法测定化妆品中氯噻酮和吩噻嗪的分析方法。化妆品中氯噻酮和吩噻嗪用丙酮超声提取,采用Kromasil C18色谱柱(5μm,250 mm×4.6 mm i.d.),以30 mmol/L NaH2PO4缓冲液(pH 5.6)和甲醇为流动相进行梯度洗脱,得到了理想的分离效果。氯噻酮和吩噻嗪在0.2~100 mg/L范围内,质量浓度与其峰面积呈良好的线性关系。在低、中、高3个添加水平下,氯噻酮的平均回收率为94.8%~104.1%,RSD为0.7%~4.4%,吩噻嗪的平均回收率为92.5%~103.1%,RSD为1.0%~6.9%。方法可用于化妆品中氯噻酮和吩噻嗪的检测。     

高效液相色谱法测定蚓粪中的植物激素

建立了高效液相色谱法（HPLC）测定蚓粪中赤霉素（GA3）和吲哚乙酸（IAA）的方法。蚓粪中植物激素可不经DEAE纤维素柱分离和薄层层析纯化,就可进行高效液相色谱测定。线性范围GA3为19.3-0.03μg,IAA为6.4-0.01μg。标准曲线的相关系数均为0.99999。GA3和IAA的最低检测量分别为0.02μg和0.004μg。