Hydrophilic interaction liquid chromatography/tandem mass spectrometry for the simultaneous determination of dasatinib,imatinib and nilotinib in mouse plasma

Hydrophilic interaction liquid chromatography (HILIC) interfaced with atmospheric pressure ionization (API) sources and a tandem mass spectrometer (MS/MS) was developed for the simultaneous determination of dasatinib, imatinib and nilotinib in mouse plasma samples. The retention profiles of all analytes on several silica stationary phases under HILIC conditions were explored. The influences of experimental factors such as the compositions of mobile phases on the chromatographic performance and the ionization efficiency of all analytes in positive ion mode were investigated. The applicability of the proposed HILIC/MS/MS approach following a protein precipitation procedure for the quantitative determination of dasatinib, imatinib and nilotinib at low nano‐mole levels was examined with respect to assay specificity and linearity. The analytical results obtained by various HILIC/MS/MS approaches were found to be in good agreement with those obtained by reversed‐phase liquid chromatography/tandem mass spectrometry (RPLC/MS/MS) methods in terms of assay sample throughputs, sensitivity and accuracy. Furthermore, the potential of matrix ionization suppression on the proposed HILIC/MS/MS systems was investigated using the post‐column infusion technique. Copyright © 2009 John Wiley & Sons, Ltd.     

Fingerprint analysis of Ligusticum chuanxiong using hydrophilic interaction chromatography and reversed-phase liquid chromatography

Fingerprint analysis is considered one of the most powerful approaches to quality control in traditional Chinese medicines (TCMs). In this study, a binary chromatographic fingerprint analysis was developed using hydrophilic interaction chromatography (HILIC) and reversed-phase liquid chromatography (RPLC) to gain more chemical information about polar compounds and weakly polar compounds. This method was used to construct a chromatographic fingerprint of Ligusticum chuanxiong. The two chromatographic methods demonstrated good precision, reproducibility, and stability, with relative standard deviations of <2% for retention time and 7% for peak area for both HILIC and RPLC separations. Data from the analysis of 14 samples by HILIC and RPLC were processed with similarity analysis, with correlation coefficients and congruence coefficients. This binary fingerprint analysis, using two chromatographic modes, is a powerful tool for characterizing the quality of samples, and can be used for the comprehensive quality control of TCMs.     

反相/亲水色谱法分析糖苷类化合物

根据皂苷、黄酮苷等糖苷类化合物的结构特点,采用亲水色谱模式分析该类化合物,以弥补反相色谱模式分离结构类似糖苷类化合物选择性的不足。首先选择14个糖苷类化合物,比较了反相色谱柱(XAqua C18)和亲水色谱柱(Click XIon)的分离效果,评价了反相/亲水色谱的正交性,并构建了反相/亲水二维体系用于西洋参样品的分离。结果表明,糖苷类化合物在反相及亲水色谱柱上均有很好的保留,但两者具有不同的分离选择性,14种物质在反相和亲水柱的出峰顺序有较大差异,在反相色谱中不易分离的人参皂苷Rg1和Re在亲水色谱柱可获得很好的分离,反相/亲水模式分离糖苷化合物具有很好的正交性。以构建的RPLC/HILIC二维色谱体系分离西洋参样品,有效地提高了分离能力及峰容量,有利于后续更多极性及微量化合物的制备、结构表征与活性研究,且该方法操作简便、流动相兼容性好,可作为糖苷分离分析、制备的有效手段,也可以为其他中药复杂体系的分析提供参考。     

亲水作用色谱固定相及其在中药分离中的应用

亲水作用色谱(HILIC)作为一种分离极性化合物的液相色谱模式,近年来越来越受到关注和重视。一方面是因为强极性化合物的分离问题引起了各个研究领域的重视,如药物分析、代谢组学、蛋白质组学等研究领域都不同程度地涉及强极性化合物的分离问题;另一方面是由于HILIC具有流动相组成简单、分离效率较高、与质谱兼容以及反压较低等优势。固定相是HILIC发展和应用的基础,本文主要从固定相分子结构的角度对HILIC固定相的结构特征、保留特性以及应用概况等进行了综述。对传统正相色谱固定相用于HILIC以及专门设计的HILIC固定相进行了介绍,评述了各自的优缺点和应用概况;对近年来HILIC固定相在中药分离中的应用进行了介绍;并对HILIC固定相的发展进行了展望。     

基于聚倍半硅氧烷微球的亲水/反相混合模式色谱填料的制备与评价

亲水/反相混合模式色谱应用广泛,但pH使用范围有限,不利于碱性药物的分离。该工作利用巯基-烯基点击化学合成了单分散多孔的半胱氨酸改性乙烯基功能化聚甲基倍半硅氧烷(C-V-PMSQ)微球。元素分析表明半胱氨酸成功键合在微球表面。C-V-PMSQ微球为介孔结构,单分散性好且具有优良的化学稳定性。以几种常见的核苷和核酸碱基作为测试样品,考察其色谱保留行为,溶质的保留因子随流动相中水相含量的变化呈现典型的U型曲线,表明C-V-PMSQ固定相具有亲水/反相的双重保留特征。使用该固定相可以分离苯的同系物及一系列亲水性与疏水性化合物。另外在高碱性流动相条件下利用亲水和反相模式成功分离了中药苦参中的3种主要活性成分,表明它在分离碱性药物方面具有较大的优势。     

以亲水作用色谱为核心的液相色谱联用技术及其应用研究

亲水作用色谱(HILIC)是近年来色谱领域研究的热点之一。本文围绕复杂体系样品中亲水性组分的分离分析,综述了国际上近年 来发展的以HILIC为核心的多种液相色谱联用技术及其应用。简要介绍了HILIC的起源、定义、分离特点及其常用固定相;比较了HILIC和反相色谱(RPLC)的选择特性;针对不同层次的分离对象和分离要求,讨论了多种基于HILIC的液相色谱以及液相色谱-质谱联用技术的分离特点和适用范围。     

亲水作用色谱及其在环境分析中的应用进展

亲水作用色谱(HILIC)是一种分离极性和亲水性化合物的液相色谱模式,其作为反相液相色谱(RPLC)的重要补充,近年来越来越受到各个领域的关注和重视。这不只是因为强极性化合物的分离问题在各个领域引起了重视,而且因为与RPLC比较,HILIC具有流动相组成黏度低、色谱柱渗透性好、与质谱联用的灵敏度高及反压较低等优势。本文简要概述了HILIC的发展历程、特点及保留机理,重点介绍了HILIC用于环境分析的最新进展,评述了HILIC及RPLC用于污染物分析的优缺点,并指出了HILIC用于环境分析的未来发展趋势。     

Design and development of a two‐dimensional system based on hydrophilic and reversed‐phase liquid chromatography with on‐line sample treatment for the simultaneous separation of excreted xenobiotics and endogenous metabolites in urine

In the present work we describe a two‐dimensional liquid chromatographic system (2D‐LC) with detection by mass spectrometry (MS) for the simultaneous separation of endogenous metabolites of clinical interest and excreted xenobiotics deriving from exposure to toxic compounds. The 2D‐LC system involves two orthogonal chromatographic modes, hydrophilic interaction liquid chromatography (HILIC) to separate polar endogenous metabolites and reversed‐phase (RP) chromatography to separate excreted xenobiotics of low and intermediate polarity. Additionally, the present proposal has the novelty of incorporating an on‐line sample treatment based on the use of restricted access materials (RAMs), which permits the direct injection of urine samples into the system. The work is focused on the instrumental coupling, studying all possible options and attempting to circumvent the problems of solvent incompatibility between the RAM device and the two chromatographic columns, HILIC and RP. The instrumental configuration developed, RAM‐HILIC‐RPLC‐MS/MS, allows the simultaneous assessment of urinary metabolites of clinical interest and excreted compounds derived from exposure to toxic agents with minimal sample manipulation. Thus, it may be of interest in areas such as occupational and environmental toxicology in order to explore the possible relationship between the two types of compounds. Copyright © 2015 John Wiley & Sons, Ltd.     

Preparation and Evaluation of Poly-l-Lysine Stationary Phase for Hydrophilic Interaction/Reversed-Phase Mixed-Mode Chromatography

In this work, a poly-l-lysine-grafted stationary phase was synthesized by polymerization of N-carboxyanhydride of l-lysine initiated by 3-aminopropylated silica. The resulting material was characterized by FT-IR spectra, elemental analysis and thermogravimetric analysis, which clearly indicated that the new phase had been prepared successfully. The retention of polar solutes depending on acetonitrile content in mobile phase exhibited ??U-shaped?? curves, which was an indication of hydrophilic interaction liquid chromatography (HILIC)/reversed-phase liquid chromatography (RPLC) mixed-mode retention behavior. The retention mechanisms in HILIC and RPLC modes also were investigated. Phenol compounds, aniline compounds and hydrophilic compounds were separated in RPLC or HILIC mode on the new stationary phase, respectively. This result shows that the new phase could be used for both RPLC and HILIC applications, providing greater flexibility for real sample analysis.     

Modeling of retention of adrenoreceptor agonists and antagonists on polar stationary phases in hydrophilic interaction chromatography: a review

Retention prediction models for reversed-phase liquid chromatography (RPLC) have been extensively studied owing to the fact that RPLC remains the most widely used chromatographic technique especially in the field of pharmaceutical and biomedical analyses. However, RPLC is not always the method of choice for the analysis of some compounds that have high polarity. Hydrophilic interaction chromatography (HILIC) has been gaining interest in the last few years as an alternative option to RPLC for the analysis of polar and hydrophilic analytes. HILIC is a variant of normal-phase liquid chromatography, but utilizes water in a water-miscible organic solvent as the eluent in conjunction with a hydrophilic stationary phase. The present review aims to summarize recent contributions on the development of retention prediction models for a group of basic analytes, namely, the adrenoreceptor agonists and antagonists, on different polar stationary phases. The use of multiple linear regression and artificial neural networks in model building is highlighted.     

三元醇丙烯酰胺键合色谱固定相的制备及评价

利用巯基与乙烯基的"点击化学"反应合成了一种新型含多羟基的硅烷偶联剂,再将其与硅胶反应制得含多羟基的亲水固定相。经过元素分析表征证明多羟基官能团已成功键合到硅胶表面。采用一系列不同性质的标准物质考察了亲水色谱模式下固定相的溶质保留机理。由于固定相结构中既具有极性多羟基官能团,也有短的疏水碳链,因此固定相兼具疏水性与亲水性。将此固定相成功应用于亲水与反相色谱两种模式,并对比了两种模式下流速对柱效的影响。最后将固定相应用于烷基苯、水溶性维生素以及核苷的分离中,取得了较好的分离效果,证明了固定相良好的应用前景。     

Ultra‐performance hydrophilic interaction liquid chromatography/tandem mass spectrometry for the determination of everolimus in mouse plasma

Ultra‐performance hydrophilic interaction liquid chromatography (UPHILIC) interfaced with the electrospray ionization (ESI) source of a tandem mass spectrometer (MS/MS) was developed for the simultaneous determination of everolimus in mouse plasma samples. UPHILIC was performed on a sub‐2 µm bare silica particle packing with the column pressure under traditional high‐performance liquid chromatography (HPLC) to allow fast separation of pharmaceutical compounds within a chromatographic analysis time of 1 min. This UPHILIC technology is comparable with reversed‐phase ultra‐performance liquid chromatography (RPUPLC) in terms of chromatographic efficiency but demands neither expensive ultra‐high‐pressure instrumentation nor new laboratory protocols. With the ESI source, multiple reaction monitoring (MRM) of the ammoniated adduct ions of the analyte was used for tandem mass spectrometric detection. The retention mechanism profiles of the test compounds under HILIC conditions were explored. The influences of experimental factors such as the compositions of mobile phases on the chromatographic performance and the ionization efficiency of the test compounds in positive ion mode were investigated. A UPHILIC/MS/MS approach following a protein precipitation procedure was applied for the quantitative determination of everolimus at the low ng/mL region in support of a pharmacodynamic study. The analytical results obtained by the UPHILIC/MS/MS approach were fond to be in good agreement with those obtained by the RPUPLC/MS/MS method in terms of assay sample throughput, sensitivity and accuracy. Copyright © 2009 John Wiley & Sons, Ltd.     

Evaluation of various chromatographic approaches for the retention of hydrophilic compounds and MS compatibility

The goal of this study was to compare the performance of three separation techniques for the analysis of 57 hydrophilic compounds. RPLC, hydrophilic interaction liquid chromatography (HILIC) and subcritical fluid chromatography (SFC) were tested. The comparison was based on the retention, selectivity, peak shape (asymmetry and peak width) and MS sensitivity. As expected, RPLC had some obvious limitations for such classes of compounds, and on average the %ACN required to elute these hydrophilic substances was 4, 7, and 11% ACN at pH 3, 6, and 9, respectively. However, a hybrid polar‐embedded C₁₈ phase with an appropriate mobile phase could represent a viable strategy for hydrophilic basic compounds with log D greater than –2 on average. HILIC and SFC were found to be more appropriate for analyzing a large majority of these hydrophilic analytes (～60 and 70% of compounds eluted during the gradient in HILIC and SFC), while maintaining good MS sensitivity. Finally, this work demonstrated the complementarity of the three analytical techniques and showed that the selection of a suitable strategy should mostly be based on physicochemical properties of the analytes (pK_a, log D, H‐bonding capability, etc.).     

Determination of Antiviral Drugs and Their Metabolites Using Micro-Solid Phase Extraction and UHPLC-MS/MS in Reversed-Phase and Hydrophilic Interaction Chromatography Modes

Two new ultra-high performance liquid chromatography (UHPLC) methods for analyzing 21 selected antivirals and their metabolites were optimized, including sample preparation step, LC separation conditions, and tandem mass spectrometry detection. Micro-solid phase extraction in pipette tips was used to extract antivirals from the biological material of Hanks balanced salt medium of pH 7.4 and 6.5. These media were used in experiments to evaluate the membrane transport of antiviral drugs. Challenging diversity of physicochemical properties was overcome using combined sorbent composed of C₁₈ and ion exchange moiety, which finally allowed to cover the whole range of tested antivirals. For separation, reversed-phase (RP) chromatography and hydrophilic interaction liquid chromatography (HILIC), were optimized using extensive screening of stationary and mobile phase combinations. Optimized RP-UHPLC separation was carried out using BEH Shield RP18 stationary phase and gradient elution with 25 mmol/L formic acid in acetonitrile and in water. HILIC separation was accomplished with a Cortecs HILIC column and gradient elution with 25 mmol/L ammonium formate pH 3 and acetonitrile. Tandem mass spectrometry (MS/MS) conditions were optimized in both chromatographic modes, but obtained results revealed only a little difference in parameters of capillary voltage and cone voltage. While RP-UHPLC-MS/MS exhibited superior separation selectivity, HILIC-UHPLC-MS/MS has shown substantially higher sensitivity of two orders of magnitude for many compounds. Method validation results indicated that HILIC mode was more suitable for multianalyte methods. Despite better separation selectivity achieved in RP-UHPLC-MS/MS, the matrix effects were noticed while using both chromatographic modes leading to signal enhancement in RP and signal suppression in HILIC.     

硅胶色谱柱的亲水作用保留机理及其影响因素

亲水作用色谱（HILIC）是替代反相色谱（RPLC）分离强极性及亲水性化合物的另一色谱模式,其分离机理与RPLC有很大不同,具有和RPLC互补的选择性。在HILIC模式中,采用正相色谱（NPLC）中的极性固定相及含高浓度有机溶剂（通常为乙腈）的水溶液为流动相。硅胶是开发最早、研究最为深入及应用最为广泛的HILIC固定相,本文介绍了硅胶色谱柱的HILIC保留机理,详细概述了操作条件如硅胶柱类型、流动相组成及柱温对HILIC分离的影响,并对硅胶填料色谱柱的HILIC模式的发展方向与应用前景进行了展望。     

基于二醛微晶纤维素功能化C18的反相/亲水色谱固定相的制备

通过十八烷基胺的氨基与二醛微晶纤维素的醛基共价键合,制备了基于二醛微晶纤维素(DMCC)官能化C₁₈的新型反相/亲水色谱固定相(C₁₈-DMCC/SiO₂),该色谱固定相被用于反相色谱(RPLC)和亲水相互作用色谱(HILIC)模式。C₁₈-DMCC/SiO₂色谱柱展现了良好的疏水选择性和芳香选择性,在反相色谱模式下可分离烷基苯和多环芳烃(PAHs)。苯胺类、酚类和糖苷类等极性化合物被用于评估该色谱柱在反相色谱模式下的极性选择性,商品C₁₈柱作对照柱,色谱评价结果令人满意。核酸碱基被用于评估C₁₈-DMCC/SiO₂色谱柱的亲水色谱性能。通过考察有机溶剂含量对分析物保留的影响,发现该新型色谱固定相具有反相/亲水色谱的典型特征。     

Determination of alkylphenol ethoxylates in textiles by normal-phase liquid chromatography and reversed-phase liquid chromatography/electrospray mass spectrometry

Comprehensive analytical methods based on pressurized liquid extraction followed by normal-phase liquid chromatography (NPLC) with ultraviolet detection and reversed-phase liquid chromatography (RPLC)/electrospray mass spectrometry (MS) have been developed for determination of alkylphenol ethoxylates (APEOs) in textile samples. NPLC with an aminosilica column allowed for the chromatographic separation of APEOs according to the increasing number of ethylene units and revealed the exact distribution of individual oligomers. RPLC coupled with electrospray MS was highly sensitive and enabled the complete qualitative and quantitative determination of individual APEOs in textile samples. The 2 analytical methods based on different chromatographic separation mechanisms, i.e., NPLC and RPLC, may provide complementary information of APEOs in textile materials. The 2 detection methods were successfully applied to the investigation of various textile samples, and the data of our research suggested actual pollution in real textile products.     

亲水/反相二维色谱法制备桔梗中的三萜皂苷

建立了亲水/反相二维色谱用于制备桔梗中三萜皂苷单体的方法。桔梗经水煮醇沉、反相和亲水两种模式的固相萃取后得到三萜皂苷类组分。选定XAmide色谱柱（150 mm×20 mm,5 μm）,以乙腈和水为流动相,在亲水色谱模式下进行组分制备。选择时间触发模式,以1 min为单位进行馏分收集,得到6~25 min之间的20个三萜皂苷精细组分。以第18个馏分（JG23）为例,在反相色谱模式下采用Atlantis Prep T3色谱柱（100 mm×30 mm,5 μm）制备,得到两个单体化合物。通过质谱和核磁共振对其进行定性,确定分别为deapi-platycoside E和platycoside E。实验结果表明,该制备方法具有好的正交选择性,对于复杂样品中三萜皂苷类化合物的分离纯化有一定的借鉴意义。     

糖类化合物在两性离子亲水作用色谱柱上的保留行为评价

糖类化合物因其极性强,在反相色谱模式下保留较弱,因此常用亲水作用色谱(HILIC)对其进行分离分析。本文以9种糖类化合物的混合物为研究对象,系统评价了其在Click TE-Cys亲水色谱柱上的保留行为,分别考察了流动相中有机相比例和盐浓度对其保留行为的影响。实验证明:9种糖类化合物按极性由小到大的顺序依次从Click TE-Cys色谱柱上被洗脱下来。随着有机相比例的增加,糖类化合物的保留增强;随着盐浓度的增加,除唾液酸外的糖类化合物的保留增强。用顶替-吸附液相相互作用模型模拟了糖类化合物在HILIC上的保留行为,采用保留方程ln k=a+blnC_B+cC_B描述HILIC的保留规律,对HILIC的保留值进行多元线性回归。结果表明糖类化合物在Click TE-Cys色谱柱上的保留行为符合HILIC的保留规律。     

Hydrophilic interaction liquid chromatography for separation and quantification of selected room-temperature ionic liquids

Hydrophilic interaction liquid chromatography (HILIC) is an alternative technique to ion pairing-reversed-phase liquid chromatography (IP-RPLC) and classical RPLC for separation of alkylimidazolium room-temperature ionic liquids (RTILs). Particularly, HILIC offers better retention and selectivity for short-chains RTILs imidazolium compounds. HILIC mechanisms were investigated by studying the influence of organic modifier content and salt concentration in the mobile phase. HILIC method was validated by quantifying 1-butyl-3-methylimidazolium cation (BMIM) degradation under gamma radiation at 2.5MGy. Development of separative reproducible analytical methods, including for low concentration, applicable to RTILs are today mandatory to improve RTILs chemistry.