反相银化高效液相色谱法测定银杏叶中银杏酚酸(英文)

 建立了反相银化高效液相色谱测定银杏叶中银杏酚酸含量的分析方法。在样品的浸提液中加入少量酸性盐溶液和吸附剂后 ,用一步反萃取法净化样品 ,有机相浓缩后供HPLC分析。流动相 :V(甲醇 )∶V(体积分数为 5 %的乙酸水溶液 ) =90∶10 ,其中银离子浓度 0 0 3mol·L-1,紫外检测波长 310nm。结果表明 4种银杏酚酸之间达到基线分离 ,该方法平均回收率为97 3% ,相对标准偏差 1 6 % ,最低检测量 0 0 2 6 μg ,可有效地用于银杏叶及其提取物中银杏酚酸的定量分析。     

超临界CO2萃取-高效液相色谱法测定银杏外种皮中银杏酚酸

建立了银杏外种皮中银杏酚酸超临界CO2萃取高效液相色谱的分析方法,使用C18液相色谱柱,以甲醇:水(85:15,V/V)为流动相,在UV310 nm下对其进行了定性定量分析,方法的线性相关系数r=0.99993。加标回收率≥97.5%,RSD小于2%,该方法已用于银杏外种皮中银杏酚酸的萃取检测。     

反相高效液相色谱分离杨树皮中酚酸化合物

对于酚酸化合物的分离,过去多用正相薄层色谱法,但效果不甚好。近来国外学者开始采用反相薄层色谱及反相液相色谱分离,效果大大提高。本文使用两种方法,在反相高效色谱柱上完成了对羟基苯甲酸、香草酸、丁香酸、对香豆酸、阿魏酸,包括对香豆酸和阿魏酸异构体的分离,并研究了上述化合物的保留值与流动相中有机相比例的关系。     

反相液相制备色谱法结合超临界流体制备色谱法分离纯化海风藤中的化合物

建立了基于反相液相制备色谱和超临界流体制备色谱的组合方法,用于分离纯化醇提水沉后石油醚层中的海风藤。首先以甲醇作为改性剂,采用醇提水沉法去除海风藤甲醇提取物中的叶绿素,加入硅藻土后用石油醚回流富集目标成分。选用反相C18制备色谱柱将其分为18个组分,然后将组分在SFC模式下进行制备。选用酰胺色谱柱,以甲醇为改性剂,在柱温30℃、背压15.0 MPa的条件下进行分离。基于反相色谱和超临界流体色谱不同的分离选择性,最后分离得到6个高纯度化合物。该法展示了反相制备色谱和超临界流体制备色谱在海风藤分离纯化方面的优势,特别是超临界流体色谱在天然产物的分析和制备方面的巨大潜力。     

反相液相色谱在蛋白质及多肽分离分析中的应用

反相液相色谱是一种以疏水作用为基础的色谱分离模式。由于它具有分辨率高、重复性好、回收率高等优点,在蛋白质及多肽的分离分析中得到了极为广泛的应用。本文简要介绍了反相液相色谱及其分离机理,对其在蛋白质和多肽研究中的应用如分离纯化、肽图分析、酶活测定、构象变化检测及疏水作用研究等作系统综述,并展望了反相液相色谱在这一领域的发展前景。     

反相离子对色谱法及其应用

由于反相离子对色谱采用目前使用最为广泛的反相高效液相色谱柱,在一般的通用型高效液相色谱仪上,一次运行可同时分离分析离子型和中性化合物,分析速度快,效率高且操作简便,因此近年来越来越受到人们的重视。 早期的反相离子对色谱是将固定液涂渍在担体     

反相高效液相色谱法快速测定大麦籽粒中13种酚酸类化合物

建立了快速测定大麦籽粒中13种酚酸类化合物(没食子酸、原儿茶酸、绿原酸、对羟基苯甲酸、咖啡酸、香草酸、丁香酸、间羟基苯甲酸、对香豆酸、阿魏酸、藜芦酸、邻香豆酸和水杨酸)的反相高效液相色谱方法.采用SUPELCOAscentis(@) C18色谱柱(150 mm×4.6 mm,5μm)分离,流动相为甲醇-0.1％甲酸水溶...     

离线二维液相色谱法分离巴天酸模根的化学成分

建立了离线二维反相/反相液相色谱分离体系（2D-RPLC/RPLC）,对巴天酸模中的化学成分进行分离。通过比较巴天酸模乙酸乙酯萃取液在环氧四氮唑和Unitary C18色谱柱上的高效液相色谱图,确定以环氧四氮唑色谱柱为第一维色谱柱,以Unitary C18色谱柱为第二维色谱柱。流动相均采用0.1%（v/v）甲酸水溶液和甲醇,梯度洗脱。经一维色谱分离后,共收集18个流分,采用二维色谱对这18个流分进行了进一步的分离分析。实验结果表明,该二维色谱分离方法高效、可行,为巴天酸模药材的微量组分的分离以及活性化合物的筛选提供了分离方法。     

离线全二维逆流色谱-液相色谱分离莪术油成分

中药挥发油成分复杂,一维色谱分离由于有限的峰容量难以完全分离中药挥发油成分,全二维气相色谱为分离挥发油成分提供了有力的方法,然而气相色谱一般无法用于天然活性成分的筛选。为建立挥发油成分全二维色谱分析新方法,研究建立以液相色谱为基础的全二维色谱分离分析方法。本文主要研究全二维逆流色谱-液相色谱分离莪术油成分的方法,并探讨两种色谱技术之间的正交性,为活性成分筛选提供新的技术支持。通过优化离线全二维逆流色谱-液相色谱分离方法,对全二维色谱峰容量、正交性和空间覆盖率进行度量。优化液相色谱分析条件并筛选逆流色谱分离两相溶剂体系,通过比色法筛选了逆流色谱两相溶剂体系并采用下相为流动相进行梯度洗脱。在290～375 min采用推挤洗脱,莪术油在第一维逆流色谱分离中达到了良好的分离。第二维反相高效液相色谱的流动相组成为乙腈(A)和水(B)。梯度洗脱程序为0～10 min, 50%A～65%A; 10～14 min, 65%A; 14～21 min, 65%A～85%A; 21～25 min, 85%A～95%A; 25～30 min, 95%A～55%A; 30～40 min, 55%A。在上述条件下...     

用反相液相色谱分离多肽时峰容量与色谱柱长度关系的研究

在蛋白质组学研究中,多肽混合物的有效分离对蛋白质鉴定和蛋白质之间相互作用的研究起着决定性的影响。基于此,用反相液相色谱研究了在两个不同长度的色谱柱上分离多肽混合物时色谱柱长度与峰容量的关系,同时考察了梯度洗脱时间对峰容量和峰宽的影响。实验结果表明,色谱柱长度对峰容量有显著的影响,而延长梯度洗脱时间不仅可以增加峰容量,而且可以增加峰宽。这说明用毛细管液相色谱 串联质谱联用方法对多肽混合物进行分离鉴定时,采用较长的色谱柱和较长的梯度洗脱时间有利于对更多的多肽进行分析鉴定。     

Preparative argentation reversed-phase high performance liquid chromatography

In this study, a preparative chromatography method named preparative argentation reversed-phase high performance liquid chromatography (Ag-RP-HPLC) was developed by adding silver ion to the mobile phase of preparative HPLC. Firstly, an analytical Ag-RP-HPLC method was developed, and the effects of silver content and acid content in the mobile phase on the column efficiency were studied. Based on the method of linear amplification, a preparative Ag-RP-HPLC technique with optimized separation conditions was developed. The new technique was applied successfully to the separation of the unsaturated aliphatic acid amide isomers contained in Asarum forbesii Maxim. Compared with the commonly used technique of argentation normal phase chromatography, this method with little solvent consumption is simple, fast, efficient, and flexible for the isolation and purification of the unsaturated compounds.     

Reversed-phase argentation high-performance liquid chromatography in phytochemical analysis of ginkgolic acids in leaves from Ginkgo biloba L

A reversed-phase argentation high-performance liquid chromatographic method has been achieved for the determination of ginkgolic acids. Liquid chromatography coupled with electrospray ionization (ESI) mass spectrometry in the negative ion mode is applied to identify ginkgolic acids from ginkgo leaves. The leaves are extracted with ethanol and then cleaned-up by extraction of analytes with hexane after addition of an acidified saturated solution of sodium sulfate and siliceous earth to the matrix solution. Ginkgolic acids are determined within 30 min on a C18 column with methanol-5% aqueous acetic acid (90:10) containing 0.03 mol l(-1) silver nitrate as eluent and with ultraviolet detection at 310 nm. Addition of silver ions as complexation agent into the mobile phase decreases retention time of ginkgolic acids with an unsaturated side chain. Four ginkgolic acids are successfully separated from each other and from other interfering components by the high selectivity of reversed-phase argentation HPLC, which is confirmed by the spectra identification. The average recovery of the method is around 97%. Good reproducibility is obtained with relative standard deviations varying from 2 to 5%.     

The retention behaviour of conjugated bile acids in reversed phase high performance liquid chromatography.

The retention behaviour of conjugated bile acids has been studied in a reversed phase high performance liquid chromatographic (RP-HPLC) system by using the mixture of methanol and aqueous phosphate buffer as the mobile phase. The retentions of the conjugates in RP-HPLC have been found to be mainly controlled by the glycine and taurine groups. The selectivity between five different glycine and taurine conjugated bile acids is a constant in RP-HPLC. This selectivity has been used for peak identification in the practical separation of conjugated bile acids.     

Open tubular supercritical fluid chromatography of triterpene acids from Dysoxylum pettigrewianum (Meliaceae)

Open tubular supercritical fluid chromatography (SFC) with carben dioxide as the mobile phase has been investigated for the separation of four triterpene acids, two of which were structural isomers. These compounds, isolated from Dysoxylum pettigrewianum (Meliaceae), were chromatographed on three stationary phases with different selectivities. 30%-biphenylmethylpolysiloxane and polyethylene glycol (Carbowax 20M) phases exhibited poor chromatographic selectivity for the compounds. The separation was improved by employing the shape selectivity of a liquid crystalline biphenylcarboxylate ester polysiloxane and utilizing simultaneous temperature and pressure programming. The elution order was explained on the basis of the molecular structures of the triterpene acids, and their interaction with the liquid crystal phase.     

Enantiomeric and diastereomeric high-performance liquid chromatographic separation of cyclic beta-substituted alpha-amino acids on a teicoplanin chiral stationary phase

High-performance liquid chromatographic (HPLC) separation of stereomeric cyclic beta-substituted or-quaternary alpha-amino acids was performed on a chiral stationary phase based on the glycopeptide antibiotic teicoplanin. The investigated amino acids are the 1-amino-2-methylcyclohexanecarboxylic acids, the 1-amino-2-hydroxycyclohexanecarboxylic acids, Ala, Cha, Phe and Tle. The effects of the mobile phase composition (type and content of organic modifier, pH) and of the temperature on the enantio- and diastereoselectivity were studied and the conditions were optimised to resolve the four stereomers of one amino acid in a single chromatographic run. The influence of the modifier concentration and the pH of the mobile phase reveal two enantiomeric and diastereomeric discrimination mechanisms based on different interactions with the stationary phase. For optimal separation of diastereomers the column has to be conditioned with an acidic eluent.     

正反相模式下键合纤维素手性固定相对手性化合物的拆分

在自行合成的键合型纤维素-(3,5-二甲基苯基氨基甲酸酯)(CDMPC-CSP)手性固定相上,在正相模式下对苯偶姻和甲霜灵外消旋体进行了拆分,考察了流动相中醇以及温度在手性识别中对手性分离的影响。同时考察了反相模式下外消旋体的拆分。     

C18柱串联冠醚手性柱高效分离3种芳香族氨基酸对映体

将C18柱与手性冠醚柱串联,建立了一种反相高效液相色谱法用于3种芳香族氨基酸对映体同时拆分的方法.考察了反相色谱流动相的组成、pH值、柱温、流速对对映体拆分的影响.实验结果表明,当流动相为HClO4-乙睛溶液(86:14,V/V,pH 2.0)、柱温20℃、流速0.4 mL/min时,3种氨基酸对映体可获得基线分离.进一步对比了C18柱、冠醚手性柱和串联顺序不同的4种分离模式,结果表明,C18柱不能拆分氨基酸对映体,仅能分离不同种类氨基酸;冠醚手性柱可分离氨基酸映体,但不同种类氨基酸色谱峰出现重叠;串联模式能实现3种氨基酸对映体的基线分离,实现双柱优势互补,而串联顺序对分离影响不大,仅影响色谱峰的峰形.     

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。