Read by QxMD icon Read

Counter current chromatography

Artak E Kostanyan
The closed-loop recycling counter-current chromatography (CLR CCC) is performed in several consecutive separation stages. First, the loop is opened, and within a specified time the solution of solutes in the mobile phase is continuously fed to the column. After the solutes loading is finished, the loop is closed, and the first separation stage starts. After a certain number of cycles the first fraction of solutes is eluted, the loop is closed, and the second separation stage starts, and so on. In this study, simple equations are presented allowing the simulation of such separation processes...
October 14, 2016: Journal of Chromatography. A
Shanshan Wang, Chao Han, Sisi Wang, Lijuan Bai, Shanshan Li, Jianguang Luo, Lingyi Kong
Cu(II) complexed amino acid ionic liquid, Cu(II)-[1-butyl-3-methylimidazolium][L-Pro] (Cu(II)-[BMIm][L-Pro]), was successfully adopted as chiral ligand to improve the enantioseparation efficiency in high speed counter-current chromatography (HSCCC). For the enantioseparation of intractable naringenin (NRG) racemic mixtures, Cu(II)-[BMIm][L-Pro] coupled with hydroxypropyl-β-cyclodextrin (HP-β-CD) was successfully applied as dual chiral selectors in HSCCC. The influence of important parameters, including the concentration of the chiral selectors, the pH value, and the temperature were investigated...
October 14, 2016: Journal of Chromatography. A
Shuting Zhang, Lingxi Li, Yan Cui, Lanxin Luo, Yuanyuan Li, Peiyu Zhou, Baoshan Sun
Separation of plant proanthocyanidins remains a major challenge for scientists due to the structural diversity and complexity. In this work, a new and effective method was developed for preparative separation of grape seed proanthocyanidins (GSPs) according to degree of polymerization (DP) by high-speed counter-current chromatography (HSCCC). Under the optimized HSCCC conditions, GSPs could be separated into seven distinct fractions (F1-F7) with mean degree of polymerization in increasing order, from 1.44 to 6...
March 15, 2017: Food Chemistry
Jing Wang, Meizhu Zheng, Lina Chen, Zhiqiang Liu, Yuchi Zhang, Chun-Ming Liu, Shu Liu
Hydroxyl radicals are the most reactive free radical of human body, a strong contributor to tissue damage. In this study, liquid chromatography coupled to electrospray ionization mass spectrometry was applied to screen and identify hydroxyl radical scavengers from the total flavonoids of Ginkgo biloba leaves, and high-performance counter current chromatography was used to separate and isolate the active compounds. Furthermore, molecular devices was used to determine hydroxyl radical scavenging activities of the obtained hydroxyl radical scavengers and other flavonoids from Ginkgo biloba leaves...
October 18, 2016: Journal of Separation Science
Chengcheng Gong, Tao Chen, Huifeng Chen, Shanshan Zhang, Xinzhu Wang, Weiqing Wang, Jing Sun, Yulin Li, Zhixin Liao
In this paper, we report an efficient method by high-speed counter-current chromatography for the first separation of four aromatic acids and two analogues with similar structures and polarities from Clematis akebioides. Firstly, the ethyl acetate extract was treated by silica gel column chromatography to enrich the target compounds. And then the fraction with target compounds were purified by high-speed counter-counter chromatography using a two-phase solvent system consisting of chloroform/acetonitrile/water (10:6:4, v/v)...
October 17, 2016: Journal of Separation Science
Jie Li, Bifei Lan, Xiaoli Li, Shumao Sun, Ping Lu, Lingyun Cheng
Transscleral drug delivery may become a safe alternative to the intravitreal injection for chronic retinal diseases such as age-related macular degeneration or diabetic macular edema. However, the drug delivered onto the sclera subjects to vigorous clearance by episcleral and choroidal circulation; in addition, the penetration from episclera to retina needs to overcome counter-directional ocular fluid current driven by intraocular pressure (IOP) as well as unfavorable drug disposition exerted by drug transporters before the drug reach retina...
October 4, 2016: Journal of Controlled Release: Official Journal of the Controlled Release Society
Lingxi Li, Shuting Zhang, Yan Cui, Yuanyuan Li, Lanxin Luo, Peiyu Zhou, Baoshan Sun
In this work, an efficient method for preparative separation of procyanidins from raw cacao bean extract by high-speed counter-current chromatography (HSCCC) was developed. Under the optimized solvent system of n-hexane-ethyl acetate-water (1:50:50, v/v/v) with a combination of head-tail and tail-head elution modes, various procyanidins fractions with different polymerization degrees were successfully separated. UPLC, QTOF-MS and (1)H NMR analysis verified that these fractions contained monomer up to pentamer respectively...
September 27, 2016: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Dan Shou, Yu Dong, Nani Wang, Hongyu Li, Yang Zhang, Yan Zhu
Natural antioxidants are widely used in the life sciences. Phellinus igniarius is a historically used natural antioxidant containing a variety of active compounds. Phenols, particularly Inoscavin A and Hypholomine B, are found in the high concentrations. Better quantitative methods are needed to perform quality control in order to support further research of this mushroom. An ultra-performance liquid chromatography method coupled to photodiode-array detection and an electrospray ionization tandem mass spectrometry method (UPLC-PAD-MS) was developed to simultaneously quantify Inoscavin A and Hypholomine B levels in the medicinal fungus Phellinus igniarius...
2016: PloS One
Huaizhi Li, Yan Cheng, Hongjing Dong, Xiao Wang, Jia Li, Qianshan Gao
Salvianolic acid A is the major bioactive compound in Danshen, however, due to the chemical instability and low content in Danshen, it is difficult to extract amount of salvianolic acid A. Therefore, this study was to establish an effective strategy for obtaining adequate amount of salvianolic acid A, subcritical water extraction was used to degrade salvianolic acid B and prepare salvianolic acid A. Different reaction conditions including temperature, time, concentration and pH value in subcritical water were investigated...
October 14, 2016: Journal of Chromatography. A
Xin-Yi Huang, Xiao-Ming Sun, Dong Pei, Duo-Long Di
Depending on the rapid growth in the radial gradient of the centrifugal force, spiral counter-current chromatography can greatly improve the retention of stationary phase, especially for the aqueous two-phase systems with ultra-polar and high viscosity that are not well retained in the conventional multilayer coils counter-current chromatography. As a result, it is an attractive and alternative technology that is suited for separation of hydrophilic compounds and has led to many exciting progress in recent years...
September 26, 2016: Journal of Separation Science
Miao Wang, Dongyu Gu, Xinfeng Guo, Haoquan Li, Yi Wang, Hong Guo, Yi Yang, Jing Tian
A rapid and efficient method using high-speed counter-current chromatography was established for the bioassay-guided separation of an active compound with protein tyrosine phosphatase 1B inhibitory activity from Sargassum fusiforme. Under the bioassay guidance, the ethyl acetate extract with the best IC50 value of 0.37±0.07 μg/mL exhibited a potential protein tyrosine phosphatase 1B inhibitory activity, which was further separated by high-speed counter-current chromatography. The separation was performed with a two-phase solvent system composed of n-hexane/methanol/water (5:4:1, v/v)...
September 23, 2016: Journal of Separation Science
Aneta Spórna-Kucab, Ewelina Hołda, Sławomir Wybraniec
Antioxidant and possible chemopreventive properties of betacyanins, natural plant pigments, contribute to a growing interest in their chemistry and separation. Mixtures of betacyanins from fresh red Gomphrena globosa L. cultivar flowers were separated in three highly polar solvent systems by high-speed counter-current chromatography (HSCCC) for a direct comparison of their separation effectiveness. Three samples of crude extract (600mg) were run on semi-preparative scale in solvent system (NH4)2SO4soln - EtOH (2...
October 15, 2016: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Tao Yi, Lin Zhu, Guo-Yuan Zhu, Yi-Na Tang, Jun Xu, Jia-Yi Fan, Zhong-Zhen Zhao, Hu-Biao Chen
This paper reports a novel strategy based on high-speed counter-current chromatography (HSCCC) technique to separate in vivo metabolites from refined extract of urine after administration of an herbal medicine. Saussurea laniceps (SL) was chosen as a model herbal medicine to be used to test the feasibility of our proposed strategy. This strategy succeeded in the case of separating four in vivo metabolites of SL from the urine of rats. Briefly, after oral administration of SL extract to three rats for ten days (2...
2016: Scientific Reports
Yin Cen, Aiping Xiao, Xiaoqing Chen, Liangliang Liu
In this study, a high-speed counter-current chromatography (HSCCC) separation method target guided by centrifugal ultrafiltration with high-performance liquid chromatography-mass spectrometry (CU-LC-MS) was proposed. This method was used to analyze α-amylase inhibitors from Kadsura longipedunculata extract. According to previous screening with CU-LC-MS, two screened potential α-amylase inhibitors was successfully isolated from Kadsura longipedunculata extract using HSCCC under the optimized experimental conditions...
2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Zhong Zhang, Tuernisan Tudi, Yanfang Liu, Shuai Zhou, Na Feng, Yan Yang, Chuanhong Tang, Qingjiu Tang, Jingsong Zhang
In this study, cordycepin, N(6)-(2-hydroxyethyl)-adenosine (HEA) and adenosine from the fruiting bodies of Cordyceps militaris were separated by using macroporous resin NKA-II adsorption. The parameters of static adsorption were tested and the optimized conditions were as follow: the total adsorption time was 12h, 50% ethanol was used for desorption and the desorption time was 9h. The crude sample that was prepared by macroporous resin NKA-II contained 3.4% cordycepin, 3.7% HEA and 4.9% adenosine. Then the crude sample was further purified by recycling high-speed counter-current chromatography (HSCCC) with ethyl acetate, n-butanol, 1...
October 15, 2016: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Qingfei Fan, Huanli Zhang, Huabin Hu, Youkai Xu, Qishi Song
Choosing a suitable solvent system for a countercurrent chromatography separation presents a challenge for many researchers. In this study, we introduce a quick method of separating a target compound from the bark of Zanthoxylum myriacanthum var. pubescens by countercurrent chromatography. This method relies on the thin-layer chromatography based generally useful estimation of solvent systems. This paper will present how to quickly choose a suitable solvent system with a thin-layer chromatography based generally useful estimation of solvent systems working chart...
October 2016: Journal of Separation Science
Hongbing Zhang, Guoyong Xie, Mei Tian, Qian Pu, Minjian Qin
The fermented leaf of Ampelopsis grossedentata has been used as a beverage and folk medicine called "vine tea" in the southern region of China. In this paper, the optimum extraction conditions for the maximum recovery amounts of total flavonoids (TF), dihydromyricetin (DMY), myricitrin (MYG) and myricetin (MY) from natural Ampelopsis grossedentata leaves subjected to ultrasonic-assisted extraction (UAE) were determined and optimized by using response surface methodology. The method was employed by the Box-Behnken design (BBD) and Derringer's desirability function using methanol concentration, extraction time, liquid/solid ratio as factors and the contents of TF, DMY, MYG and MY as responses...
2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Jian-Ming He, Shi-Yue Zhang, Qing Mu
Counter-current Chromatography (CCC) has gradually become a popular method for preparative separation, especially in natural product isolation. As an effective separation method, one-dimensional (1D) CCC often results in insufficiently resolved peaks, due to limitations in the separation efficiency and peak capacity in an equipment. Therefore, two dimensional (2D)/multi-dimensional (multi-D) CCC strategies with recycling elution mode were developed to achieve successful separation of target compounds. However, the reported 2D or multi-D CCC approaches lead to experimental costs, complicated procedures, higher requirements for equipment, and increased time consumption...
September 16, 2016: Journal of Chromatography. A
Ranhao Wang, Qi Liu, Zhiliang Wu, Meiling Wang, Xiaoqing Chen
An off-line two-dimensional high-speed counter-current chromatography strategy combined with the wavelength switching technique and extrusion elution mode was successfully developed and applied to the isolation of polar antioxidants from Abelmoschus esculentus (L).Moench. Target-guided by the result of 2,2-diphenyl-1-picrylhydrazyl screening assay, four antioxidants were obtained with purities over 90% through orthogonal high-speed counter-current chromatography separation. UV spectroscopy, mass spectrometry and (1) H NMR spectroscopy were employed to identify their structures, which were assigned as l-tryptophan, quercetin-3-O-sophoroside, 5,7,3',4'-tetrahydroxyflavonol-3-O-[β-d-rhamnopyranosil-(1→2)]-β-d-glucopyranoside, and quercetin-3-O-glucoside...
October 2016: Journal of Separation Science
Huaizhi Li, Yongqing Zhang, Qian Liu, Changlei Sun, Jia Li, Peng Yang, Xiao Wang
High-speed counter-current chromatography (HSCCC) has been successfully used for the separation of eight compounds from Chimonanthus praecox flowers. Firstly, the crude extract of Chimonanthus praecox flowers was dissolved in a two-phase solvent system composed of petroleum ether-ethyl acetate-methanol-H₂O (5:5:3:7, v/v) and divided into two parts: the upper phase (part I) and the lower phase (part II). Then, HSCCC was applied to separate the phenolic acids from part I and part II, respectively. Considering the broad polarity range of target compounds in part I, a stepwise elution mode was established...
2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"