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Offline two-dimensional liquid chromatography coupled with ion mobility-quadrupole time-of-flight mass spectrometry enabling fourdimensional separation and characterization of the multicomponents from white ginseng and red ginseng 被引量:13
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作者 Tiantian Zuo Chunxia Zhang +7 位作者 Weiwei Li Hongda Wang Ying Hu Wenzhi Yang Li Jia Xiaoyan Wang Xiumei Gao Dean Guo 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第6期597-609,共13页
Inherent complexity of plant metabolites necessitates the use of multi-dimensional information to accomplish comprehensive profiling and confirmative identification.A dimension-enhanced strategy,by offline two-dimensi... Inherent complexity of plant metabolites necessitates the use of multi-dimensional information to accomplish comprehensive profiling and confirmative identification.A dimension-enhanced strategy,by offline two-dimensional liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry(2 D-LC/IM-QTOF-MS)enabling four-dimensional separations(2 D-LC,IM,and MS),is proposed.In combination with in-house database-driven automated peak annotation,this strategy was utilized to characterize ginsenosides simultaneously from white ginseng(WG)and red ginseng(RG).An offline 2 DLC system configuring an Xbridge Amide column and an HSS T3 column showed orthogonality 0.76 in the resolution of ginsenosides.Ginsenoside analysis was performed by data-independent high-definition MSE(HDMSE)in the negative ESI mode on a Vion?IMS-QTOF hybrid high-resolution mass spectrometer,which could better resolve ginsenosides than MSEand directly give the CCS information.An in-house ginsenoside database recording 504 known ginsenosides and 58 reference compounds,was established to assist the identification of ginsenosides.Streamlined workflows,by applying UNIFI?to automatedly annotate the HDMSEdata,were proposed.We could separate and characterize 323 ginsenosides(including 286 from WG and 306 from RG),and 125 thereof may have not been isolated from the Panax genus.The established 2 D-LC/IM-QTOF-HDMSEapproach could also act as a magnifier to probe differentiated components between WG and RG.Compared with conventional approaches,this dimensionenhanced strategy could better resolve coeluting herbal components and more efficiently,more reliably identify the multicomponents,which,we believe,offers more possibilities for the systematic exposure and confirmative identification of plant metabolites. 展开更多
关键词 Dimension-enhanced strategy Multicomponent characterization GINSENOSIDE Offline two-dimensional liquid chromatography Ion mobility-quadrupole time-of-flight mass spectrometry In-house database
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Establishing a protein expression profile database for the normal human pituitary gland using two-dimensional high-performance liquid chromatography combined with LTQ-Orbitrap mass spectrometry 被引量:2
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作者 Rong Xie Wei Xu +4 位作者 Weimin Bao Hang Liu Luping Chen Yiwen Shen Jianhong Zhu 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第36期2922-2928,共7页
In this study, we selected adult normal pituitary gland tissues from six patients during operations for pituitary microadenomas via the transsphenoidal approach for extended normal pituitary tissue resection around th... In this study, we selected adult normal pituitary gland tissues from six patients during operations for pituitary microadenomas via the transsphenoidal approach for extended normal pituitary tissue resection around the tumor, and analyzed the protein expression of human normal pituitary using two-dimensional high-performance liquid chromatography combined with LTQ-Orbitrap mass spectrometry proteomics technology. The ten most highly expressed proteins in normal human pituitary were: alpha 3 type VI collagen isoform 5 precursor (abundance among tall pituitary proteins 1.30%), fibrinogen beta chain preproprotein (0.99%), vimentin (0.73%), prolactin (0.69%), ATP synthase, H~ transporting and mitochondrial F1 complex beta subunit precursor (0.52%), keratin I (0.49%), growth hormone (0.45%), carbonic anhydrase I (0.40%), heat shock protein 90 kDa I (0.31%), and annexin V (0.30%). Based on the biological function classifications of these proteins, the top three categories by content were neuroendocrine proteins (abundance among all pituitary proteins, 40.1%), catalytic and metabolic proteins (28.3%), and cell signal transduction proteins (9.8%). Based on cell positioning classification, the top three categories were cell organelle (24.5%) membrane (20.8%), and cytoplasm (13.0%). Based on biological process classification, the top three categories of proteins are involved in physiological processes (42.9%), cellular processes (40.4%), and regulation of biological processes (9.1%). Our experimental findings indicate that a protein expression profile database of normal human pituitary can be precisely and efficiently established by proteomics technology. 展开更多
关键词 two-dimensional high-performance liquid chromatography mass spectrum pituitary gland PROTEINS PROTEOMICS hypophyseal tumor physiological function pathological mechanism
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Separation of Three Major Active Components from Eleutherine americana Merr.et K.Heyne Using High-speed Counter-current Chromatography Combined with Silica Gel Column Chromatography
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作者 Wanyu ZUO Yalan LUO +2 位作者 Bingyu CHENG Luyang LU Jizhong ZHANG 《Medicinal Plant》 2025年第6期17-21,共5页
[Objectives]To establish an efficient and environmentally friendly separation and purification method for the large-scale preparation of the major active components-eleutherol,eleutherine,and isoeleutherine-from the e... [Objectives]To establish an efficient and environmentally friendly separation and purification method for the large-scale preparation of the major active components-eleutherol,eleutherine,and isoeleutherine-from the ethnomedicinal plant Eleutherine americana Merr.et K.Heyne.[Methods]The sample of E.americana bulbs was initially extracted with ethanol,followed by three successive extractions with ethyl acetate-water(2:1,V/V)to obtain the target component-enriched fraction.Eight solvent systems were systematically optimized,and a mixture of petroleum ether-ethyl acetate-ethanol-water(5:5:6:4,V/V/V/V)was identified as the optimal solvent system for high-speed counter-current chromatography(HSCCC)separation under conditions of 900 rpm,2 mL/min,and 35℃.The crude HSCCC product was further purified by silica gel column chromatography(200-300 mesh)using gradient elution with a solvent system of n-hexane-dichloromethane-ethyl acetate(varying from 10:5:1 to 4:5:1,V/V/V).UPLC-PDA(Agilent SB-C_(18)column)and nuclear magnetic resonance spectroscopy(600 MHz)were comprehensively employed to assess compound purity and confirm molecular structures.[Results]An optimized technique integrating HSCCC and silica gel column chromatography was established,successfully enabling the large-scale preparation of three bioactive components:eleutherol(purity 99%),eleutherine(purity 98%),and isoeleutherine(purity 98%).Structural identification results were consistent with those reported in the literature.Compared to traditional methods,the new approach demonstrated improved separation efficiency and reduced solvent consumption.[Conclusions]The combined separation method utilizing HSCCC and silica gel column chromatography established in this study demonstrates notable advantages,including high efficiency,environmental friendliness,and cost-effectiveness,enabling the large-scale preparation of the three major active components from E.americana.This approach outperforms conventional methods by offering higher separation efficiency,reduced solvent consumption,and superior product purity,providing a robust technical solution for the development and utilization of bioactive compounds from E.americana.Moreover,it offers a novel methodological reference for the isolation and purification of other natural products. 展开更多
关键词 Eleutherine americana High-speed counter-current chromatography(HSCCC) Silica gel column chromatography Separation and purification
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Rapid and simultaneous determination of imidazolium and pyridinium ionic liquid cations by ion-pair chromatography using a monolithic column 被引量:8
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作者 Xu Huang Hong Yu Ying Jie Dong 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第7期843-846,共4页
A method for rapid and simultaneous determination of imidazolium and pyridinium ionic liquid cations by ion-pair chromatography with ultraviolet detection was developed. Chromatographic separations were performed on a... A method for rapid and simultaneous determination of imidazolium and pyridinium ionic liquid cations by ion-pair chromatography with ultraviolet detection was developed. Chromatographic separations were performed on a reversed-phase silica-based monolithic column using 1-heptanesulfonic acid sodium-acetonitrile as mobile phase. The effects of ion-pair reagent and acetonitrile concentration on retention of the cations were investigated. The retention times of the cations accord with carbon number rule. The method has been successfully applied to the determination of four ionic liquids synthesized by organic chemistry laboratory. 展开更多
关键词 Ionic liquids Ion-pair chromatography Monolithic column Ultraviolet detection
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Trace analysis of anions in organic matrices by ion chromatography coupled with a novel reversed-phase column for on-line sample pretreatment 被引量:4
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作者 Ying Ying Zhong Wen Fang Zhou +2 位作者 Xue Ling Zeng Ming Li Ye Yan Zhu 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第4期461-464,共4页
An ion chromatography(IC) system coupled with on-line column-switching technique was used to determine anions ofμg/g levels in organic chemicals of analytical reagent grade.A novel polystyrene-divinylbenzene-carbon... An ion chromatography(IC) system coupled with on-line column-switching technique was used to determine anions ofμg/g levels in organic chemicals of analytical reagent grade.A novel polystyrene-divinylbenzene-carbon nanotube(PS-DVB-CNT) stationary phase was utilized for matrix elimination.A calibration study was conducted by preparing and analyzing eight concentrations(between 10 and 5000μg/L) of eight standards in deionized water.The linearity was between 0.9978 and 1.And the detection limits ranged from 1.54μg/L to 10.02μg/L.A spiking study was performed on two representative organic chemicals.The recoveries were between 84.3%and 119.6%. 展开更多
关键词 Ion chromatography column switching Trace anions Organic matrix Polymer stationary phase
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Optimization of Preparative Separation and Purification of Total Polyphenols from Sargassum tenerrimum by Column Chromatography 被引量:4
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作者 Samee Haider LI Zhenxing +1 位作者 LIN Hong Khalid Jamil 《Journal of Ocean University of China》 SCIE CAS 2009年第4期425-430,共6页
Polyphenols from the ethanol extracts of Sargassum tenerrimum (ST) with potent antiallergic effects were studied to optimize separation process through column chromatography. The adsorption and desorption characteri... Polyphenols from the ethanol extracts of Sargassum tenerrimum (ST) with potent antiallergic effects were studied to optimize separation process through column chromatography. The adsorption and desorption characteristics of three widely used adsorbents: macroporous resin, silica gel, and polyvinylpolypyrrolidone (PVPP), were critically evaluated respectively and studied for the optimization of preparative separation of polyphenols. Static operations on these adsorbents showed that macroporous resin had the best adsorption and desorption capability among the three adsorbents. Dynamic adsorption and desorption with macroporous resin packed column were also conducted to optimize the parameters such as: with the optimal values shown in brackets, the concen- tration of extract solution (4 times diluted), pH value (6-7), adsorption speed (3BVh-1, bed volumes/per hour), concentration of ethanol (80%), elution speed (3 BV ht) and elution volume (7 BV). The chromatographic process so optimized gave a purity of 62.43% from the crude polyphenols, providing a promising basis for large scale preparation of bioactive polyphenols upon further scaling up tests. 展开更多
关键词 Sargassum tenerrimum POLYPHENOL SEPARATION ADSORPTION DESORPTION column chromatography
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Determination of Five Organic Acids in Radix Isatidis by Column Partition Chromatography and Capillary Zone Electrophoresis柱分配色谱-毛细管区带电泳联用分析板蓝根中五种微量有机酸(英文) 被引量:5
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作者 CHAIYi-fen JISong-gang +1 位作者 ZHANGGuo-qing LIUChang-hai 《Journal of Chinese Pharmaceutical Sciences》 CAS 2003年第4期192-195,共4页
Aim To determine five organic acids in Radix Isatidis . Method The extraction method and the column partition chromatographic conditions were studied. Then a capillary zone electrophoretic method was set up for t... Aim To determine five organic acids in Radix Isatidis . Method The extraction method and the column partition chromatographic conditions were studied. Then a capillary zone electrophoretic method was set up for the determination. Results The linear ranges of quinazolinone acid, n anthranilic acid, benzoic acid, salicylic acid, and syringic acid were 5 52-92 0 μg·mL -1 , 5 12-102 μg·mL -1 , 2 28-84 4 μg·mL-1 , 4 78-159 μg·mL -1 , and 1 74-87 0 μg·mL -1 respectively. Conclusion The established method is accurate and simple. 展开更多
关键词 Radix Isatidis organic acids capillary electrophoresis column partition chromatography
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Group separation and analysis of a carbon disulfide-soluble fraction from Shenfu coal by column chromatography 被引量:6
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作者 DING Ming-jie ZONG Zhi-min +7 位作者 ZONG Ying OUYANG Xiao-dong HUANG Yao-guo ZHOU Lei ZHENG Yu-xuan ZHOU Xiao WEI Yan-bin WEI Xian-yong 《Journal of China University of Mining and Technology》 EI 2008年第1期27-32,共6页
A carbon disulfide-soluble fraction (CDSSF) from Shenfu coal was separated into five fractions by silica-gel column chromatography using hexane and n-hexane/ethyl acetate binary eluent. The five fractions include four... A carbon disulfide-soluble fraction (CDSSF) from Shenfu coal was separated into five fractions by silica-gel column chromatography using hexane and n-hexane/ethyl acetate binary eluent. The five fractions include four clear group fractions and a nonpolar fraction. All the fractions were analyzed by GC/MS. A total of 204 compounds were detected from the original CDSSF and its further separated fractions, with 173 compounds more than those detected by studying the original CDSSF directly. The results demonstrate a clear group separation by column chromatography in coal organic components and a more accessibility to coal components compared with the solvent extraction only. 展开更多
关键词 group separation column chromatography COAL
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Separation and purification of deoxynivalenol(DON) mycotoxin from wheat culture using a simple two-step silica gel column chromatography 被引量:7
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作者 ZHAO Xiu-mei LI Rong-jia +5 位作者 ZHOU Chuang ZHANG Jie HE Cheng-hua ZHENG Ya-ting WU Wen-da ZHANG Hai-bin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第3期694-701,共8页
Deoxynivalenol(DON) is a type B trichothecenes mycotoxin produced by several Fusarium species, often found in foodstuffs for humans and animals. DON is in great demand for the toxicological researches both in vivo a... Deoxynivalenol(DON) is a type B trichothecenes mycotoxin produced by several Fusarium species, often found in foodstuffs for humans and animals. DON is in great demand for the toxicological researches both in vivo and in vitro. In this work, wheat culture was inoculated with a Fusarium graminearum PH-1 strain for DON production. The solvent system for crude extraction was acetonitrile-water(84:16, v/v). A simple two-step silica gel column chromatography was employed to separate the DON mycotoxin from wheat culture, combined with preparative high performance liquid chromatography(preparative HPLC) to purify the compound. The solvent system for the second silica gel column chromatography was methylene chloride-methanol(17:1, v/v), which provided a good elution effect selected on thin layer chromatography(TLC). The target compound was identified by HPLC, and the chemical structure was confirmed by mass spectrometry(MS) and ~1H and ^(13)C nuclear magnetic resonance(NMR) spectroscopy. A total of 433 mg of purified DON was obtained from 1 kg of wheat culture, with a purity of 99.01%. The study had provided an easy-operating and cost-effective method to isolate an expensive compound in a simple way. 展开更多
关键词 deoxynivalenol silica gel column chromatography separation purification
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Separation of liquefied product of Salix psammophila by column chromatography and structure analysis of its components 被引量:2
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作者 GAO Guan-hui HUANG Jin-tian 《Forestry Studies in China》 CAS 2008年第4期274-279,共6页
The liquefied product of Salixpsammophila wood was separated by thin-layer chromatography (TLC) and column chromatography, and its structure was identified by nuclear magnetic resonance (NMR) spectra in our study.... The liquefied product of Salixpsammophila wood was separated by thin-layer chromatography (TLC) and column chromatography, and its structure was identified by nuclear magnetic resonance (NMR) spectra in our study. The separation result indicates that the sample of liquefied S. psammophila contained at least two categories of components. The structure of the main components was guaiacyl C-1, C-2 of the hydroxyphenyl propane, i.e., the aromatic nucleus protons of lignin. Degradation and polycondensation reactions occurred when the S. psammophila wood was liquefied in phenol. Polycondensation reactions occurred among the depolymerization products from cellulose, the aromatic depolymerization products from lignin and the products of the displacement reactions between phenoxide ion and cellulose. 展开更多
关键词 liquefied residue of Salix psammophila thin-layer chromatography (TLC) column chromatography separation nuclearmagnetic resonance (NMR)
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Preparative separation of high-purity troxerutin and related substances from mother liquor of troxerutin by silica gel column chromatography and semi-preparative liquid chromatography 被引量:2
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作者 Shaojing Liu Bei Qin +3 位作者 Hongfang Han Li Li Lili Yu Xiaojing Xu 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2020年第7期487-493,共7页
Troxerutin(TRO)is a mixture of semi-synthetic flavonoids prepared by hydroxyethylation of rutin,and it is commonly used for the treatment of cerebrovascular diseases.The main active ingredient is trishydroxyethyl ruti... Troxerutin(TRO)is a mixture of semi-synthetic flavonoids prepared by hydroxyethylation of rutin,and it is commonly used for the treatment of cerebrovascular diseases.The main active ingredient is trishydroxyethyl rutin.The mother liquor of TRO contains a lot of TRO and other derivatives of hydroxyethylated rutin.In order to make full use of the mother liquor of TRO,an efficient method was developed for recovering high-purity TRO from mother liquor of TRO by combining silica gel column chromatography with semi-preparative liquid chromatography.In the silica gel column chromatographic separation,the ratio of silica gel to sample and eluent composition were investigated to obtain optimum separation effect.The results showed that when the ratio of silica gel to sample was 50,and acetone–ethyl acetate–water–glacial acetic acid(10:10:3:1,v/v/v/v)was used as the eluent,the separation effect of TRO and adjacent impurities was good.Moreover,150 g of TRO with a purity of 80%could be obtained from 1 kg of mother liquor of TRO by the silica gel column chromatographic separation,and the results were consistent with the quality standard of TRO raw material.Subsequently,the semi-preparative HPLC was performed,and 100 g TRO with a purity of up to 98%(w/w)was obtained.Meanwhile,tetrahydroxyethylrutin and tetrahydroxyethylquercetin with purity greater than 98%were obtained.This work proposed the separation and preparation of TRO with high-purity from the production waste of TRO for the first time,which had certain environmental benefits and economic benefits. 展开更多
关键词 Mother liquor of troxerutin TROXERUTIN Silica-gel column chromatography Semi-preparative HPLC NMR
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Separation and analysis of six fractions in low temperature coal tar by column chromatography 被引量:1
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作者 Shuangtai Liu Lei He +5 位作者 Qiuxiang Yao Xi Li Linyang Wang Jing Wang Ming Sun Xiaoxun Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第6期256-265,共10页
The low temperature coal tar(CT)is taken as the raw material,and the extraction and column chromatography are used for detailed and accurate characterization in this paper.The n-heptane soluble fraction(CT-HS)and inso... The low temperature coal tar(CT)is taken as the raw material,and the extraction and column chromatography are used for detailed and accurate characterization in this paper.The n-heptane soluble fraction(CT-HS)and insoluble fraction(CT-HI)were obtained by n-heptane Soxhlet extraction.The extraction rate of CT-HS reached 92.79%(mass),which indicated that there are few heavy compounds in it.Further,different solvents(methylbenzene,benzene,ethyl acetate,methylbenzene-ethanol)were used to elute CT-HS by chromatographic column to obtain five fractions(saturates,aromatics,heteroatoms,phenolics and resins,named CT-SA,CT-AR,CT-HE,CT-PH,CT-RE,respectively).The yields of CTSA,CT-AR,CT-HE,CT-PH,CT-RE are 42.12%,10.43%,2.19%,9.50%and 6.63%(mass),respectively.Gas chromatography-mass spectrometry analysis of eluting components show that alkanes are the main components in CT,followed by polycyclic aromatics,and the corresponding fractions are CT-SA and CT-AR,respectively.The relative content of aliphatics in CT-SA is 76.93%,and the relative content of aromatics in CT-AR is 75.05%.This separation technology effectively separates and enriches different components in CT,and the activation energy required for the pyrolysis process of a single eluting fraction is lower than that of CT,which is expected to provide an important reference for the separation,analysis and conversion of complex oil products such as coal-oil co-processing products,coal tar and other complex heavy carbon oil products. 展开更多
关键词 Low temperature coal tar Extractive separation column chromatography isolation chromatography/mass spectrometry
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Simultaneous enantioseparation and simulation studies of atenolol,metoprolol and propranolol on Chiralpak^■IG column using supercritical fluid chromatography 被引量:1
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作者 Pranav A.Pandya Priyanka A.Shah Pranav S.Shrivastav 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2021年第6期746-756,共11页
Enantioseparation of threeβ-blockers,i.e.,atenolol,metoprolol and propranolol,was studied on amylose tris(3-chloro-5-methylphenylcarbamate)immobilized chiral stationary phase using supercritical fluid chromatography(... Enantioseparation of threeβ-blockers,i.e.,atenolol,metoprolol and propranolol,was studied on amylose tris(3-chloro-5-methylphenylcarbamate)immobilized chiral stationary phase using supercritical fluid chromatography(SFC).The effect of organic modifiers(methanol,isopropanol and their mixture),column temperature and back pressure on chiral separation ofβ-blockers was evaluated.Optimum chromatographic separation with respect to resolution,retention,and analysis time was achieved using a mixture of CO_(2) and 0.1%isopropyl amine in isopropanol:methanol(50:50,V/V),in 75:25(V/V)ratio.Under the optimized conditions,the resolution factors(Rs)and separation factors(a)were greater than3.0 and 1.5,respectively.Further,with increase in temperature(25-45℃)and pressure(100-150 bars)there was corresponding decrease in retention factors(k),a and Rs.However,a reverse trend(a and Rs)was observed for atenolol with increase in temperature.The thermodynamic data from van’t Hoff plots revealed that the enantioseparation was enthalpy driven for metoprolol and propranolol while entropy driven for atenolol.To understand the mechanism of chiral recognition and the elution behavior of the enantiomers,molecular docking studies were performed.The binding energies obtained from simulation studies were in good agreement with the elution order found experimentally and also with the free energy values.The method was validated in the concentration range of 0.5-10μg/m L for all the enantiomers.The limit of detection and limit of quantitation ranged from 0.126 to 0.137μg/m L and 0.376-0.414μg/m L,respectively.The method was used successfully to analyze these drugs in pharmaceutical preparations. 展开更多
关键词 ENANTIOSEPARATION Supercritical fluid chromatography Β-BLOCKERS Chiralpak^(■)IG column Molecular docking Binding energy
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Separation of Inorganic Anions Using Methacrylate-Based Monolithic Column Modified with Trimethylamine in Ion Chromatography Capillary System 被引量:1
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作者 Fitri Mairizki Athika Rahmah +6 位作者   Hilma Radhia Putri Rahmiana Zein Lee Wah Lim Toyohide Takeuchi Edison Munaf 《American Journal of Analytical Chemistry》 2013年第9期451-456,共6页
Methacrylate-based monolithic column was prepared in fused-silica capillary (80 ′ 0.32 mm i.d.) by in situ polymerizetion reaction using glycidyl methacrylate as monomer;ethylene dimethacrylate as crosslinker;1-propa... Methacrylate-based monolithic column was prepared in fused-silica capillary (80 ′ 0.32 mm i.d.) by in situ polymerizetion reaction using glycidyl methacrylate as monomer;ethylene dimethacrylate as crosslinker;1-propanol, 1,4-butanediol, and water as porogenic solvents. The monolith matrix was modified with trimethylamine to create strong anion exchanger via ring opening reaction of epoxy groups. The morphology of the monolithic column was studied by using Scanning Electron Microscope (SEM). This column had good mechanical stability and permeability. The effects of various mobile phases for separation of inorganic anions were investigated. Iodate, bromate, nitrite, bromide, and nitrate were separated within 11 min using100 mMpotassium chloride as mobile phase and detected at 210 nm. This method showed good precision of retention time, acceptable linearity and good sensitivity. Under the optimum condition, the RSD of the retention time was in the range of 1.09%-1.75% (n = 6). The calibration curve showed linear relationships between the peak area and the concentration. The limits of detection (LOD) and the limits of quantitation (LOQ) were between 0.08-0.18 mM and 0.26-0.61 mM, respectively. This method was applied to the determination of inorganic anions in tap water and ground water samples. 展开更多
关键词 Methacrylate-Based Monolithic column TRIMETHYLAMINE Ion chromatography CAPILLARY SYSTEM Inorganic Anions Water Sample
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Research Progress on the Separation of Alkaloids from Chinese Medicines by Column Chromatography 被引量:2
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作者 Yaqin He Zhaozeng Chen +1 位作者 Haibin Qu Xingchu Gong 《Advances in Chemical Engineering and Science》 2020年第4期358-377,共20页
Alkaloids have a variety of bioactivities and great development value in the fields of pharmaceuticals, cosmetics and health food. Column chromatography is a common method for preparing alkaloids. In this paper, the r... Alkaloids have a variety of bioactivities and great development value in the fields of pharmaceuticals, cosmetics and health food. Column chromatography is a common method for preparing alkaloids. In this paper, the research status of the separation and purification of alkaloids from Chinese medicines by column chromatography is reviewed, and the factors that influence the refining of alkaloids via a macroporous adsorption resin, ion exchange resin and silica gel are summarized. The thermodynamic and kinetic modeling methods for the static adsorption of adsorbents are also reviewed in this paper. It is suggested that the modeling method of the column chromatography process be deeply studied to establish a more stringent quality control method for sampling liquid and to strengthen the online detection of the chromatography process to improve the refining effect of alkaloids. 展开更多
关键词 ALKALOID column chromatography Ion Exchange Resin Macroporous Adsorbent Resin Model Silica Gel
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Column Chromatography: A Facile and Inexpensive Procedure to Purify the Red Dopant DCJ Applied for OLEDs 被引量:1
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作者 Khadijeh Ghanbari Hassan Aghajani +3 位作者 Maryam Golbabaee Elham Naemi Khah Seyed Hassan Nabavi Ata Koohian 《Advances in Materials Physics and Chemistry》 2011年第3期91-93,共3页
DCJ, one of the DCM derivatives, has been used as a laser dye and a red emitter or a red dopant for OLED devices in recent decade. 4-(dicyanomethylene)-2-methyl-6-(julolidyl-9-enyl)-4H-pyran (DCJ) containing julolidin... DCJ, one of the DCM derivatives, has been used as a laser dye and a red emitter or a red dopant for OLED devices in recent decade. 4-(dicyanomethylene)-2-methyl-6-(julolidyl-9-enyl)-4H-pyran (DCJ) containing julolidine group has been synthesized for use as a red fluorescent dye molecule in organic light-emitting di- odes (OLEDs). In this paper, we reported a facile, simple and inexpensive procedure of purification of DCJ without necessity of HPLC analysis. The maximum absorption, emission, quantum efficiency are increasing in DCJ with the electron-donating of julolidine group. 展开更多
关键词 PURIFICATION column chromatography Absorption Emission Quantum Efficiency
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Determination of petroleum sulfonates in crude oil by column-switching anion-exchange chromatography 被引量:4
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作者 Liang Zhao Xu Long Cao +2 位作者 Hong Yan Wang Xia Liu Sheng Xiang Jiang 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第2期219-222,共4页
A column-switching anion-exchange chromatography method was described for the separation and determination of petroleum monosulfonates (PMS) and petroleum disulfonates (PDS) in crude oil that was simply diluted wi... A column-switching anion-exchange chromatography method was described for the separation and determination of petroleum monosulfonates (PMS) and petroleum disulfonates (PDS) in crude oil that was simply diluted with the dichloromethane/methanol (60/40). The high performance liquid chromatography (HPLC) system consisted of a clean-up column and an analytical column, which were connected with two six-port switching valves. Detection of petroleum sulfonates was available and repeatable. This method has been successfully applied to determine PMS and PDS in crude oil samples from Shengli oil field. 展开更多
关键词 Petroleum sulfonate DETERMINATION Anion-exchange chromatography column-SWITCHING Crude oil
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Comprehensive analysis of phenolic composition and antioxidant mechanisms in Gymnema sylvestre extracts using LC-MS and column chromatography 被引量:1
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作者 Shengjie Hao Yuxin Du +2 位作者 Jianglong He Qian Li Guilin Chen 《Asian Journal of Traditional Medicines》 2024年第4期211-222,共12页
Recent studies have highlighted the potential of plant extracts as therapeutic agents for managing oxidative stress and related disorders.This study aims to elucidate the phenolic composition and antioxidant propertie... Recent studies have highlighted the potential of plant extracts as therapeutic agents for managing oxidative stress and related disorders.This study aims to elucidate the phenolic composition and antioxidant properties of Gymnema sylvestre extracts.Ethanolic reflux extraction followed by column chromatography was employed to isolate phenolic compounds.The total phenolic and flavonoid contents were quantified using the Folin–Ciocalteu and aluminum chloride colorimetric methods,respectively.Antioxidant activities were assessed by DPPH,ABTS scavenging assays and the ferric reducing antioxidant power(FRAP)assay.High-Performance Liquid Chromatography(HPLC)with a C18 column and Thermo TSQ Quantum Access Max(LC-MS)were used to determine the levels of gymnemic acid and identify other potential phenolic compounds.The analysis revealed significant antioxidant activities in the fractions.Fraction A showed the highest DPPH and ABTS scavenging activities,and Fraction C demonstrated the highest ferric reducing power.LC-MS analysis identified several phenolic compounds,indicating that these are major contributors to the antioxidant efficacy of the extract.This study provides a detailed phenolic profile and confirms the strong antioxidant potential of Gymnema sylvestre leaf extract,supporting its therapeutic use and further investigation. 展开更多
关键词 Gymnema sylvestre ANTIOXIDANTS column chromatography phenolic compounds LC-MS
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Identification of Glyphosate Herbicide with Ion Chromatographic Column Switching Method
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作者 Xie Peijin Li Gang +2 位作者 Yang Hongda Zhang Qinjie Sun Jianying 《Plant Diseases and Pests》 CAS 2017年第6期41-44,共4页
[Objective] The paper was to establish the method for quantitative analysis of glyphosate herbicide and identification of salt type. [Method] Using ion chromatographic column switching method,cations( sodion,ammonium ... [Objective] The paper was to establish the method for quantitative analysis of glyphosate herbicide and identification of salt type. [Method] Using ion chromatographic column switching method,cations( sodion,ammonium ion,potassium ion,dimethonium ion and isopropylamine ion) and glyphosate anion in glyphosate salt were determined with Thermo IonP ac SCS1 cation exchange column and Thermo IonP ac AS14 anion exchange column,and external standard method was used for quantification. [Result] Various components showed good linear relationship within the linearity range,and the correlation coefficient r was greater than 0. 999; the relative standard deviation of retention time and peak area were less than 0. 13% and 1. 22%,respectively; the recovery was 98. 22%-99. 97%.[Conclusion] The method is precise,accurate and simple,and can be used to determine the active ingredients of glyphosate herbicide. 展开更多
关键词 GLYPHOSATE ION chromatography column SWITCHING
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柱后衍生液相色谱法测定茶酒中的果糖、葡萄糖和蔗糖
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作者 李丽霞 成洲 +2 位作者 李丹 钟晓雪 罗学平 《中国酿造》 北大核心 2026年第1期288-294,共7页
该研究建立了一种柱后衍生液相色谱法测定茶酒中果糖、葡萄糖和蔗糖含量的方法。采用Asahipak NH2P-50 4E色谱柱(250 mm×4.6 mm,5μm),以含0.5%H3PO4的乙腈-水(75∶25,V/V)为流动相进行等度洗脱,流速0.8 m L/min,柱温40℃,柱后120... 该研究建立了一种柱后衍生液相色谱法测定茶酒中果糖、葡萄糖和蔗糖含量的方法。采用Asahipak NH2P-50 4E色谱柱(250 mm×4.6 mm,5μm),以含0.5%H3PO4的乙腈-水(75∶25,V/V)为流动相进行等度洗脱,流速0.8 m L/min,柱温40℃,柱后120℃下采用2.0 g/L高碘酸氧化、1.0 g/L酚试剂进行衍生显色,于波长670 nm处检测。结果表明,果糖在25.0~500.0 mg/L、葡萄糖和蔗糖在50.0~1 000.0 mg/L质量浓度范围内具有良好的线性关系,相关系数(R^(2))>0.999,方法 检出限为2.58~9.64 mg/L,定量限为7.82~29.21 mg/L,加标回收率为96.55%~98.73%,精密度、稳定性试验结果相对标准偏差均<2.00%。利用本方法对市售的4类共11款茶酒中3种糖含量进行检测,结果表明在所有茶酒中均检测出葡萄糖,含量为0.038~111.36 g/L,10款茶酒中检测出果糖,含量为0.023~115.90 g/L,其中配制型茶酒中的葡萄糖、果糖含量最高;蔗糖仅在3款露酒型茶酒中检出,含量为0.012~0.380 g/L。该方法操作简便、试剂成本低、回收率高,可为茶酒的工艺研究、产品开发及标准制定等提供新的检测技术支持。 展开更多
关键词 液相色谱 柱后衍生 紫外检测 茶酒 糖类物质
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