高效液相色谱法测定α-萘乙酸

 采用高效液相色谱法 ,以HypersilC1 8( 4 6mmi d × 2 50mm ,5μm)为色谱柱 ,甲醇 水 磷酸 (体积比为 60∶40∶0 35,pH 3～ 4)为流动相 ,检测波长为 2 72nm ,测定了α 萘乙酸的质量分数。在 1 6mg/L～1 0 0 0mg/L时 ,质量浓度与峰面积线性关系良好 (r =0 9997) ,精密度RSD为 0 8% (n =5)。方法简便 ,准确。     

正交轴逆流色谱法对标准蛋白及中等分子量大豆肽的分离

本文报道分别以12．5％PEG8000-25％磷酸氢二钾(质量比1：1)的溶剂系统，以及正丁醇：三氟乙酸：水(120：1：160，V／V)的溶剂系统，用下相作流动相，上相作固定相，采用500r／min的转速和1mL／min流动相流速对标准蛋白质及大豆肽进行分离。在分离度损失不大的基础上提高了进样量，证明了正交轴逆流色谱法用于制备的有效性。为采用正交轴逆流色谱法分离制备天然生物肽提供了可选择的方法。     

高效液相色谱手性流动相添加剂分离西孟坦对映体

以 β 环糊精作为手性流动相添加剂 ,研究了DL 西孟坦在反相HPLC系统中的拆分。考察了缓冲盐的浓度、pH、β 环糊精的浓度、流动相中甲醇的比例、流动相流速和温度对手性分离的影响 ,建立了 β 环糊精动态手性固定相法分离西孟坦对映体的方法。色谱条件为 :ZirchromKromasilODS 1(5 μm ,15 0mm× 4 .6mm)色谱柱 ,流动相为 2 0mmol/L磷酸盐缓冲液 (pH 6 .0 )含 12mmol/Lβ 环糊精∶甲醇 (70∶30 ,V/V) ,流速为 0 .8mL/min ,温度为 17℃。DL 西孟坦对映体的保留时间分别为 2 2 .5和 2 4 .5min ,分离度为 1.5 7。     

使用大环糖肽抗生素键合固定相高效液相色谱法直接拆分卡巴拉汀

采用高效液相色谱法在大环糖肽抗生素键合固定相手性柱上拆分了卡巴拉汀(Rivastigmine)对映体。考察了甲醇∶乙酸∶三乙胺流动相体系中乙酸和三乙胺的浓度和比例、有机酸的种类、分离温度及流动相流速对拆分结果的影响。选定的色谱条件为:Chirobiotic V手性柱(250mm×4.6mmi.d.,5μm),流动相为V(甲醇)∶V(乙酸)∶V(三乙胺)=100∶0.02∶0.01,柱温5℃,流速0.5mL/min,检测波长274nm。在柱温5~30℃范围内测定lnα与1/T呈线性关系:lnα=ΔΔH0/RT ΔΔR0/R。     

等度反相高效液相色谱法测定茶多酚中的儿茶素和咖啡因

 介绍一种简便的等度反相高效液相色谱分析茶多酚中 5种儿茶素和咖啡因的快速方法。样品总的分析时间在 0 5h内。色谱柱为ResolveC18;流动相为水 体积分数为 85 %的磷酸水溶液 乙腈 N ,N 二甲基甲酰胺 (DMF)(体积比为 85 9∶1∶12 0∶2 0 ) ;柱温为 43℃ ;紫外检测波长为 2 80nm。研究了流动相中改良剂DMF与容量因子的关系。被测组分的含量与其峰面积有良好的线性关系 (r =0 .9992～ 0 .9999) ;加标回收率在 83.33%～ 10 4.42 %(RSD在 0 .74%～ 1.43% )。     

反相高效液相色谱法测定盐酸索他洛尔

建立了用于盐酸索他洛尔的含量测定、有关物质的检查和稳定性考察的 RP-HPL C法。采用 ODS柱、体积分数为 0 .1 %的乙酸水溶液 -乙腈 (体积比为 80∶ 2 0 )为流动相的色谱条件 ,以磺胺二甲基嘧啶为内标物 ,测定的线性范围为 5～ 45 mg/ L(r=0 .9991 ) ,日内精密度为 0 .2 0 % ,日间精密度为 0 .93 %。     

反相高效液相色谱法测定盐酸索他洛尔

 建立了用于盐酸索他洛尔的含量测定、有关物质的检查和稳定性考察的 RP-HPL C法。采用 ODS柱、体积分数为 0 .1 %的乙酸水溶液 -乙腈 (体积比为 80∶ 2 0 )为流动相的色谱条件 ,以磺胺二甲基嘧啶为内标物 ,测定的线性范围为 5～ 45 mg/ L(r=0 .9991 ) ,日内精密度为 0 .2 0 % ,日间精密度为 0 .93 %。     

高效液相色谱手性流动相添加剂法拆分氯噻酮对映体

应用反向高效液相色谱,以羟丙基-β-环糊精(HP--βCD)作为手性流动相添加剂,拆分了氯噻酮(Chlorthalidone)对映体。对主要的影响因素如羟丙基-β-环糊精浓度、流动相pH值、三乙胺(TEA)、甲醇、柱温、流速等进行了系统研究,建立了羟丙基-β-环糊精流动相添加剂法拆分氯噻酮对映体的方法。使用HarbonLichrospher-C18色谱柱(5μm,150 mm×4.6 mm),流动相为V(甲醇)∶V(水相)=20∶80(水相含30 mmol/L HP--βCD0、.1 mol/L Na2HPO4、体积分数2%的TEA、pH5),流速为0.8 mL/min,室温下拆分,氯噻酮对映体可得到良好分离。     

高速逆流色谱法对独角莲中有效成分皂苷的分离纯化

本文采用高速逆流色谱法对独角莲中的有效成分皂苷进行分离纯化.分别以乙酸乙酯∶正丁醇∶乙腈∶水=5∶1∶1∶5(V/V)及乙酸乙酯∶正丁醇∶乙醇∶水=5∶10∶2∶20(V/V)为溶剂系统,用下相作流动相,上相作固定相,分别采用2 mL/min及1.5 mL/min 的流动相流速、800 r/min的转速对独角莲中的有效成分皂苷进行分离,得到纯度98%的胡萝卜苷6 mg.     

反相高效液相色谱法测定己酮可可碱氯化钠注射液中己酮可可碱的含量

建立了反相高效液相色谱法测定己酮可可碱氯化钠注射液中己酮可可碱含量的方法。使用DiamansilC18柱 (15 0mm× 4 .6mmi.d .,5 μm) ,流动相为甲醇 -水 (体积比为 4 0∶6 0 ) ,流速为 1mL/min ,测定波长为 2 74nm。线性范围为 12 .5～ 30 0 .0 μg/mL ,线性回归方程为A =4 4 .6 6 2 8c - 17.119 2 ,相关系数r=0 .999 87,检出限为 5ng/mL。测量结果的相对标准偏差为 0 .5 4 % (n =6 ) ,平均回收率为 10 0 .81%。     

Counter-current chromatographic separation of glycoprotein components from Morchella esculenta (L.) with a polymer phase system by a cross-axis coil planet centrifuge

Using a cross-axis coil planet centrifuge, glycoproteins were separated from fermentation media of Morchella esculenta (L.) by high-speed counter-current chromatography. The performance of the apparatus was optimized with four standard proteins including pepsin, lysozyme, ovalbumin and hemoglobin and a polymer phase system composed of 12.5% (w/w) polyethylene glycol 8000 and 25% (w/w) potassium phosphate in distilled water at various pH values. Separations were performed by eluting the lower phosphate-rich phase at a flow-rate of 1.0 ml/min. Under the optimized conditions three glycoprotein components in Morchella esculenta (L.) were resolved within 6 h.     

Enantioseparation of chiral aromatic acids by multiple dual mode counter‐current chromatography using hydroxypropyl‐β‐cyclodextrin as chiral selector

This work concentrates on extending the utilization of multiple dual mode (MDM) counter‐current chromatography in chiral separations. Two aromatic acids, 2‐(6‐methoxy‐2‐naphthyl)propionic acid (NAP) and 2‐phenylpropionic acid (2‐PPA), were enantioseparated by MDM counter‐current chromatography using hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD) as chiral selector. The two‐phase solvent systems consisting of n‐hexane/ethyl acetate 0.1 mol/L phosphate buffer pH 2.67 containing 0.1 mol/L HP‐β‐CD (7.5:2.5:10 for NAP and 7:3:10 for 2‐PPA, v/v/v) were used. Conventional MDM and modified MDM were compared according to peak resolution under current separation mechanism. The influence of elution time after the first‐phase inversion and number of cycles for MDM were investigated. Peak resolution of NAP and 2‐PPA increased from 0.62 to 1.05 and 0.72 to 0.84, respectively, using optimized MDM conditions. Being an alternative elution method for counter‐current chromatography, MDM elution greatly improved peak resolution in chiral separations.     

Separation and purification of four compounds from Desmodium styracifolium using off‐line two‐dimensional high‐speed counter‐current chromatography

An off‐line 2D high‐speed counter‐current chromatography technique in preparative scale has been successfully applied to separate and purify the main compounds from the ethyl acetate extract of Desmodium styracifolium. A two‐phase solvent system composed of n‐hexane/ethyl acetate/methanol/water at an optimized volume ratio of 1:2:1:2 v/v/v/v was used. Conventional high‐speed counter‐current chromatography was used as the first dimension, and the upper phase of the solvent system was used as the stationary phase in the head‐to‐tail elution mode at a flow rate of 2.0 mL/min and a rotation speed of 900 rpm. Recycling high‐speed counter‐current chromatography served as the second dimension to separate an impure fraction of the first dimension. A total of four well‐separated substances including vanillic acid ( 1 ), β‐sitosterol ( 2 ), formononetin ( 3 ), and aromadendrin ( 4 ) were obtained, and their purities and structures were identified by HPLC–MS and ¹H NMR spectroscopy. The results illustrated that off‐line 2D high‐speed counter‐current chromatography is an effective way to isolate compounds in complex samples.     

Combinative application of pH‐zone‐refining and conventional high‐speed counter‐current chromatography for preparative separation of caged polyprenylated xanthones from gamboge

An efficient method for the preparative separation of four structurally similar caged xanthones from the crude extracts of gamboge was established, which involves the combination of pH‐zone‐refining counter‐current chromatography and conventional high‐speed counter‐current chromatography for the first time. pH‐zone‐refining counter‐current chromatography was performed with the solvent system composed of n‐hexane/ethyl acetate/methanol/water (7:3:8:2, v/v/v/v), where 0.1% trifluoroacetic acid was added to the upper organic stationary phase as a retainer and 0.03% triethylamine was added to the aqueous mobile phase as an eluter. From 3.157 g of the crude extract, 1.134 g of gambogic acid, 180.5 mg of gambogenic acid and 572.9 mg of a mixture of two other caged polyprenylated xanthones were obtained. The mixture was further separated by conventional high‐speed counter‐current chromatography with a solvent system composed of n‐hexane/ethyl acetate/methanol/water (5:5:10:5, v/v/v/v) and n‐hexane/methyl tert‐butyl ether/acetonitrile/water (8:2:6:4,v/v/v/v), yielding 11.6 mg of isogambogenic acid and 10.4 mg of β‐morellic acid from 218.0 mg of the mixture, respectively. The purities of all four of the compounds were over 95%, as determined by high‐performance liquid chromatography, and the chemical structures of the four compounds were confirmed by electrospray ionization mass spectrometry and NMR spectroscopy. The combinative application of pH‐zone‐refining counter‐current chromatography and conventional high‐speed counter‐current chromatography shows great advantages in isolating and enriching the caged polyprenylated xanthones.     

Enrichment and separation of antitumor triterpene acids from the epidermis of Poria cocos by pH‐zone‐refining counter‐current chromatography and conventional high‐speed counter‐current chromatography

Triterpene acids were extracted from the epidermis of Poria cocos (Schw.) Wolf. These acids were found to inhibit the growth of lung cancer cells in vitro and in vivo. An efficient method for the preparative separation of antitumor triterpene acids was established that involves the combination of pH‐zone‐refining counter‐current chromatography and conventional high‐speed counter‐current chromatography. We used pH‐zone‐refining counter‐current chromatography to concentrate the triterpene acids using a two‐phase solvent system composed of petroleum ether/ethyl acetate/methanol/water (3:7:5:5, v/v/v/v), trifluoroacetic acid (10 mM) was added to the upper phase as a retainer, and ammonia (10 mM) was added to the lower phase as an eluter. As a result, 200 mg concentrate of triterpene acids was obtained from 1.0 g of crude extract. The concentrate was further separated by conventional high‐speed counter‐current chromatography using a solvent system composed of petroleum ether/ethyl acetate/methanol/water (0.8:1.2:1.2:0.9, v/v), yielding 50 mg of poricoic acid A and 5 mg of poricoic acid B from 120 mg concentrate, respectively. The inhibitory activity of the major compound on lung A549 cells was examined and poricoic acid A was found to significantly inhibit the growth of A 549 cells.     

Isolation and purification of alkaloids from the fruits of Macleaya cordata by ionic‐liquid‐modified high‐speed counter‐current chromatography

Macleaya cordata (Willd) R. Br. is a medicinal plant. The most important bioactive compounds of M. cordata are alkaloids that have many biological activities including antifungal, anti‐inflammatory, and antitumor. In this study, an ionic‐liquid‐modified high‐speed counter‐current chromatography method was established to obtain alkaloids from the fruits of M. cordata. The conditions of ionic‐liquid‐modified high‐speed counter‐current chromatography, including solvent systems, the content of ionic liquid (1‐butyl‐3‐methylimidazolium tetrafluoroborate [C₄mim][BF₄]), and the posttreatment of the ionic liquid, were investigated. Five alkaloids protopine, allocryptopine, sanguinarine, 8‐O‐demethylchelerythrine, and chelerythrine were separated from the extract of the fruits using a high speed counter‐current chromatography with two‐phase solvent system composed of dichloromethane/methanol/0.3 mol/L hydrochloric acid aqueous solution/[C₄mim][BF₄] (4:2:2:0.015, v/v). Their purities were 96.33, 95.56, 97.94, 96.22, and 97.90%, respectively. The results indicated that a small amount of ionic liquids as modifier of the two‐phase solvent system could shorten the separation time and improve the separation efficiency of the alkaloids from the fruits. The ionic‐liquid‐modified high‐speed counter‐current chromatography would provide a feasible way for highly effective separation of alkaloids from natural products.     

pH‐Zone‐refining counter‐current chromatography for two new lipo‐alkaloids separated from refined alkaline extraction of Kusnezoff monkshood root

An efficient and refined method for the separation of six aconitine‐type alkaloids from the alkaline prepared “Kusnezoff monkshood root” was established. It is the first study that two new lipo‐alkaloids were successfully isolated from refined sample by pH‐zone‐refining counter‐current chromatography rather than synthetic method. It was of interest that a great deal of lipo‐alkaloids was produced in crude extract from the alkalization of “Kusnezoff monkshood root.” A refined sample method was proposed to enrich two types of alkaloids by liquid–liquid extraction, i.e. lipo‐alkaloids and monoester‐diterpenoid alkaloids. The pH‐zone‐refining counter‐current chromatography was performed with an optimized two‐phase solvent system composed of n‐hexane‐ethyl acetate–methanol–water (3:5:4:5, v/v), where upper organic phase was added to 3 mmol/L triethylamine as a retainer and lower aqueous mobile phase was added to 3 mmol/L hydrochloric acid as an eluter. As a result, six aconitum alkaloids, including two lipo‐alkaloids (8‐lino‐14‐benzoylaconine, 8‐pal‐14‐benzoylaconine), three monoester‐diterpenoid alkaloids (14‐benzoylmesaconine, 14‐benzoylaconine, beyzoyldeoxyaconine), and one aconine alkaloid (neoline) were acquired from the plant at the same time. The anti‐inflammatory activities of the two new lipo‐alkaloids were compared to the six alkaloids in vitro, in cyclo‐oxygen‐ase‐2 inhibition assays. The separation mechanism of six alkaloids by pH‐zone‐refining counter‐current chromatography was illustrated.     

Separation of caffeoylquinic acids and flavonoids from Asteris souliei by high‐performance counter‐current chromatography and their anti‐inflammatory activity in vitro

Eleven compounds were successfully separated from Asteris souliei by using a two‐step high‐performance counter‐current chromatography method. The first step involved a reversed phase isocratic counter‐current chromatography separation using hexane/ethyl acetate/methanol/water (1:0.8:1:1 v/v/v/v), which produced three fractions, the first two of which were mixtures. The second step used step‐gradient reversed‐phase counter‐current chromatography with hexane/butanol/ethyl acetate/methanol/water (1:0.5:3.5:1:4 v/v/v/v/v) initially followed by hexane/ethyl acetate/methanol/water (1:2:1:2 v/v/v/v) to separate Fraction 1 into seven compounds; and hexane/ethyl acetate/methanol/water (1:1:1:1.2 v/v/v/v) to separate Fraction 2 into three further compounds. The chemical structures of the separated compounds were identified by ESI‐MS and NMR spectroscopy (¹H and ¹³C). Baicalin ( 5 ), eriodictyol ( 7 ), apigenin‐7‐glycoside ( 8 ), quercetin ( 9 ), luteolin ( 10 ), and apigenin ( 11 ) showed obvious inhibitory effects on lipopolysaccharide‐induced nitric oxide production in RAW264.7 cells at a concentration of 10 μg/mL.     

Separation of phenolic acids from sugarcane rind by online solid‐phase extraction with high‐speed counter‐current chromatography

Sugarcane rind contains some functional phenolic acids. The separation of these compounds from sugarcane rind is able to realize the integrated utilization of the crop and reduce environment pollution. In this paper, a novel protocol based on interfacing online solid‐phase extraction with high‐speed counter‐current chromatography (HSCCC) was established, aiming at improving and simplifying the process of phenolic acids separation from sugarcane rind. The conditions of online solid‐phase extraction with HSCCC involving solvent system, flow rate of mobile phase as well as saturated extent of absorption of solid‐phase extraction were optimized to improve extraction efficiency and reduce separation time. The separation of phenolic acids was performed with a two‐phase solvent system composed of butanol/acetic acid/water at a volume ratio of 4:1:5, and the developed online solid‐phase extraction with HSCCC method was validated and successfully applied for sugarcane rind, and three phenolic acids including 6.73 mg of gallic acid, 10.85 mg of p‐coumaric acid, and 2.78 mg of ferulic acid with purities of 60.2, 95.4, and 84%, respectively, were obtained from 150 mg sugarcane rind crude extracts. In addition, the three different elution methods of phenolic acids purification including HSCCC, elution–extrusion counter‐current chromatography and back‐extrusion counter‐current chromatography were compared.     

Accelerated solvent extraction and pH‐zone‐refining counter‐current chromatographic purification of yunaconitine and 8‐deacetylyunaconitine from Aconitum vilmorinianum Kom

This study aimed to seek an efficient method to extract and purify yunaconitine and 8‐deacetylyunaconitine from Aconitum vilmorinianum Kom. by accelerated solvent extraction combined with pH‐zone‐refining counter‐current chromatography. The major extraction parameters for accelerated solvent extraction were optimized by an orthogonal test design L₉ (3)⁴. Then a separation and purification method was established using pH‐zone‐refining counter‐current chromatography with a two‐phase solvent system composed of petroleum ether/ethyl acetate/methanol/water (5:5:2:8, v/v) with 10 mM triethylamine in the upper phase and 10 mM HCl in the lower phase. From 2 g crude extract, 224 mg of 8‐deacetylyunaconitine (I) and 841 mg of yunaconitine (II) were obtained with a purity of over 98.0%. The chemical structures were identified by ESI‐MS and ¹H and ¹³C NMR spectroscopy.