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Mirjana Minceva - One of the best experts on this subject based on the ideXlab platform.
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a water free solvent system containing an l menthol based deep eutectic solvent for centrifugal Partition Chromatography applications
Journal of Chromatography A, 2019Co-Authors: Franziska Bezold, Mirjana MincevaAbstract:Centrifugal Partition Chromatography (CPC) is a well-established technology for natural compound separation. However, the separation of hydrophobic compounds is still challenging since the number of non-aqueous biphasic systems that can be used in CPC is limited. In this work, we evaluate quaternary solvent systems composed of n-heptane, methanol, and a eutectic solvent composed of L-menthol and levulinic acid, containing DES-constituents in both phases. It was evaluated whether the phases of the systems can be used as stationary and mobile phases for CPC separations. For this purpose, solutes that cover a broad range of octanol-water Partition coefficients, i.e. hydrophobic to hydrophilic compounds, were used and shake flask experiments were performed to determine solute Partition coefficients. The Partition coefficients indicated that the more hydrophobic compounds were in the favored range for CPC and, thus, the systems are high potential candidates for the separation of hydrophobic compounds. In this particular solute set, the biphasic systems were most suitable for compounds with octanol-water Partition coefficients between 2.1 and 12.0. It was shown that the biphasic systems with low initial DES-content are stable in presence of water, while L-menthol precipitates from the biphasic systems with high initial DES content when water is added. High stationary phase retention of up to 79.1% could be obtained and the selected model compounds were separated with high resolution in pulse injections, which confirmed the high potential of the biphasic solvent systems for CPC.
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trapping multiple dual mode centrifugal Partition Chromatography for the separation of intermediately eluting components throughput maximization strategy
Journal of Chromatography A, 2017Co-Authors: Raena Morley, Mirjana MincevaAbstract:Trapping multiple dual mode centrifugal Partition Chromatography (trapping MDM CPC) is an alternative to isocratic pulse injections for the separation of intermediately-eluting components from complex mixtures using liquid-liquid Chromatography. In this work, a throughput maximization strategy is developed and validated to investigate the full potential of trapping MDM CPC as a preparative technique. In the proposed approach, shake flask and stationary phase retention experiments are used to determine the maximum feed concentration and flow rate, respectively. A model-based parameter selection process combining a mathematical short-cut method and simulations based on the equilibrium cell model is used to obtain the column loading and step durations resulting in maximized process throughput. The proposed throughput maximization strategy is experimentally validated for the separation of a ternary model mixture of parabens. A preliminary comparison of trapping MDM CPC separation performance to that of stacked pulse injections is also made.
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trapping multiple dual mode centrifugal Partition Chromatography for the separation of intermediately eluting components operating parameter selection
Journal of Chromatography A, 2017Co-Authors: Johannes Goll, Raena Morley, Mirjana MincevaAbstract:Abstract The preparative separation of intermediately-eluting components in liquid-liquid Chromatography is commonly performed with isocratic batch injections, a technique which often leads to low yield and/or purity as a result of peak overlap. Two-column trapping multiple dual mode centrifugal Partition Chromatography, an alternative discontinuous method for the separation of a mixture into three product fractions (early-, intermediately-, and late-eluting components) at full recovery, is presented in this work. A mathematical shortcut method based on equilibrium theory assumptions is derived for the determination of the key operating parameters (i.e., step durations and number of steps). The feasibility of the technique and the accompanying short-cut method is demonstrated by proof-of-concept experiments for the separation of two paraben model mixtures.
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computational solvent system screening for the separation of tocopherols with centrifugal Partition Chromatography using deep eutectic solvent based biphasic systems
Journal of Chromatography A, 2017Co-Authors: Franziska Bezold, Maria E Weinberger, Mirjana MincevaAbstract:Abstract Tocopherols are a class of molecules with vitamin E activity. Among those, α-tocopherol is the most important vitamin E source in the human diet. The purification of tocopherols involving biphasic liquid systems can be challenging since these vitamins are poorly soluble in water. Deep eutectic solvents (DES) can be used to form water-free biphasic systems and have already proven applicable for centrifugal Partition Chromatography separations. In this work, a computational solvent system screening was performed using the predictive thermodynamic model COSMO-RS. Liquid-liquid equilibria of solvent systems composed of alkanes, alcohols and DES, as well as Partition coefficients of α-tocopherol, β-tocopherol, γ-tocopherol, and σ-tocopherol in these biphasic solvent systems were calculated. From the results the best suited biphasic solvent system, namely heptane/ethanol/choline chloride-1,4-butanediol, was chosen and a batch injection of a tocopherol mixture, mainly consisting of α- and γ-tocopherol, was performed using a centrifugal Partition Chromatography set up (SCPE 250-BIO). A separation factor of 1.74 was achieved for α- and γ-tocopherol.
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Deep eutectic solvents in countercurrent and centrifugal Partition Chromatography.
Journal of Chromatography A, 2016Co-Authors: Simon Roehrer, Eva Marra García, Franziska Bezold, Mirjana MincevaAbstract:Deep eutectic solvents (DESs) were evaluated as solvents in centrifugal Partition Chromatography, a liquid-liquid Chromatography separation technology. To this end, the Partition coefficients of ten natural compounds of different hydrophobicity were determined in non-aqueous biphasic systems containing DES. The influence of the composition of DESs and the presence of water in the biphasic system on the Partition coefficient were also examined. In addition, several process relevant physical properties of the biphasic system, such as the density and viscosity of the phases, were measured. A mixture of three to four hydrophobic compounds was successfully separated in a centrifugal Partition extractor using a heptane/ethanol/DES biphasic system.
Jean-hugues Renault - One of the best experts on this subject based on the ideXlab platform.
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Industrial case study on alkaloids purification by pH-zone refining centrifugal Partition Chromatography
Journal of Chromatography A, 2016Co-Authors: Alexis Kotland, Jean-hugues Renault, Sebastien Chollet, Jeremy Meucci, Catherine Diard, Jean-marie Autret, Luc MarchalAbstract:The industrial potential of pH-zone refining centrifugal Partition Chromatography has been evaluated by studying the purification of pharmaceutical ingredients at the pilot scale. For the first time, a scale up methodology based on both column capacity and mass transfer efficiency as invariants was developed. The purification of catharanthine and vindoline from an industrial crude extract of aerial parts of Catharanthus roseus, was used as a case of study. Toluene/CH3CN/water (4/1/5, v/v/v) was selected as biphasic solvent system, triethylamine as retainer in the organic stationary phase and sulphuric acid as displacer in the aqueous mobile phase. The separation intensification was performed on a 36 mL CPC column equipped with 832 Partition twin-cells. The combined effects of four parameters (displacer and retainer concentrations for intensive parameters, flow rate and rotational speed for extensive parameters) were studied by design of experiment in order to maximize both recoveries and productivities. Then, scale change was done on two larger columns (305 mL and 1950 mL of capacity) equipped with only 231 and 238 Partition cells. For this step, it has been shown that the global mass transfer coefficient k0a (the efficiency of a column design) and the stationary phase retention (the capacity of the column) were relevant and useful scale up invariants. A CPC model based on acid-base equilibriums and interfacial mass transfer in continuously stirred tank reactors in series was used to predict fully separations on larger CPC column at the optimized operating conditions and to guide the CPC user in its scale-up strategy. The experimental validation on pilot CPC column, by injecting up to 150 g of Catharanthus roseus crude extract on the 1950 mL column highlighted the preservation of the separation quality, the non-linear character of the scale up in centrifugal Partition Chromatography and that a productivity of about 4 kg of processed crude extract per day can be reached by implementing developed methodology.
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methodology for optimally sized centrifugal Partition Chromatography columns
Journal of Chromatography A, 2015Co-Authors: Sebastien Chollet, Jean-hugues Renault, Luc Marchal, Jack Legrand, Jeremy Meucci, Alain FoucaultAbstract:Abstract Centrifugal Partition Chromatography (CPC) is a separation process based on the Partitioning of solutes between two partially miscible liquid phases. There is no solid support for the stationary phase. The centrifugal acceleration is responsible for both stationary phase retention and mobile phase dispersion. CPC is thus a process based on liquid–liquid mass transfer. The separation efficiency is mainly influenced by the hydrodynamics of the phases in each cell of the column. Thanks to a visualization system, called “Visual CPC”, it was observed that the mobile phase can flow through the stationary phase as a sheet, or a spray. Hydrodynamics, which directly governs the instrument efficiency, is directly affected during scale changes, and non-linear phenomena prevent the successful achievement of mastered geometrical scale changes. In this work, a methodology for CPC column sizing is proposed, based on the characterization of the efficiency of advanced cell shapes, taking into account the hydrodynamics. Knowledge about relationship between stationary phase volume, cell efficiency and separation resolution in CPC allowed calculating the optimum cell number for laboratory and industrial scale CPC application. The methodology is highlighted with results on five different geometries from 25 to 5000 mL, for two applications: the separation of alkylbenzene by Partitioning with heptane/methanol/water biphasic system; and the separation of peptides by Partitioning with n-butanol/acetic acid/water (4/1/5) biphasic system. With this approach, it is possible to predict the optimal CPC column length leading to highest productivity.
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dereplication of depsides from the lichen pseudevernia furfuracea by centrifugal Partition Chromatography combined to 13c nuclear magnetic resonance pattern recognition
Analytica Chimica Acta, 2014Co-Authors: Sarah K Oettl, Jean-hugues Renault, Jean-marc Nuzillard, Hermann Stuppner, Jane Hubert, Judith M RollingerAbstract:Abstract Lichens produce a diversity of secondary metabolites, among them depsides comprised of two or more hydroxybenzoic acid units linked by ester, ether, or C C-bonds. During classic solid support-based purification processes, depsides are often hydrolyzed and in many cases time, consuming procedures result only in the isolation of decomposition products. In an attempt to avoid extensive purification steps while maintaining metabolite structure integrity, we propose an alternative method to identify the major depsides of a lichen crude extract (Pseudevernia furfuracea var. ceratea (Ach.) D. Hawksw., Parmeliaceae) directly within mixtures. Exploiting the acidic character of depsides and differences in polarity, the extract was fractionated by centrifugal Partition Chromatography in the pH-zone refining mode resulting in twelve simplified mixtures of depsides. After 13C nuclear magnetic resonance analysis of the produced fractions, the major molecular structures were directly identified within the fraction series by using a recently developed pattern recognition method, which combines spectral data alignment and hierarchical clustering analysis. The obtained clusters of 13C chemical shifts were assigned to their corresponding molecular structures with the help of an in-house 13C NMR chemical shift database, resulting in six unambiguously identified compounds, namely methyl β-orcinolcarboxylate (1), atranorin (2), 5-chloroatranorin (3), olivetol carboxylic acid (4), olivetoric acid (5), and olivetonide (6).
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purification of antibiotics from the biocontrol agent streptomyces anulatus s37 by centrifugal Partition Chromatography
Journal of Chromatography B, 2014Co-Authors: Olivier Couillerot, Jean-marc Nuzillard, Alix Toribio, Souad Loqman, Jane Hubert, Lea Gandner, Yedir Ouhdouch, Christophe Clement, Essaid Ait Barka, Jean-hugues RenaultAbstract:A novel actinomycete strain, Streptomyces anulatus S37, has been isolated from the rhizosphere of healthy Moroccan Vitis vinifera on the basis on its ability to promote grapevine growth and to induce natural defences against various phytopathogens. In the present work, the main bioactive metabolites produced by S. anulatus S37 were isolated. A crude n-BuOH extract of the S37 fermentation broth was firstly Partitioned in a biphasic solvent system composed of n-heptane, methanol, and water (5:1.5:3.5, v/v). The most active organic fraction (1.1g) as revealed by TLC-bioautography was subsequently separated by a two-step centrifugal Partition Chromatography procedure. The first separation was performed in the ascending mode at 6mL/min with the biphasic solvent system n-heptane, ethyl acetate, methanol and water (2:1:2:1, v/v), to finally recover 40mg of a pure compound identified as streptochlorin by NMR spectroscopy. In a second separation, the solvent system n-heptane, acetonitrile, and water (5:5:4, v/v) was used in the ascending mode at 3mL/min to purify 135mg of nigericin and 53mg of piericidin A1. Assays performed with the three compounds have confirmed their inhibitory impact on the growth of Botryris cinerea in dual confrontation and also on V. vinifera L. plantlets.
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pilot scale ion exchange centrifugal Partition Chromatography purification of sinalbin from white mustard seeds
IEEE Journal of Solid-state Circuits, 2009Co-Authors: Alix Toribio, Benoit Pinel, François De La Poype, Jean-marc Nuzillard, Leslie Boudesocque, Michel Lafosse, Jean-hugues RenaultAbstract:The purification of p-hydroxybenzylglucosinolate (sinalbin) on a multigram scale from a crude aqueous extract of white mustard seeds (Sinapis alba var. concerta) was successfully achieved by scaling up a strong ion-exchange centrifugal Partition Chromatography (SIXCPC) laboratory procedure. Thus, the one-step sinalbin purification was performed with 2.35 g of crude extract in approximately 170 min (830 mg/h) up to 70.3 g in approximately 160 min (26.3 g/h) by switching from a 200 mL laboratory scale column to a 5.7 L pilot-scale column. The required biphasic solvent system contained ethyl acetate, n-butanol, and water in 3:2:5 v/v/v proportions, Aliquat 336 (trioctylmethyl ammonium chloride) was added to the organic stationary phase (80 mM) and acted as ion-exchanger. Potassium iodide in the aqueous mobile phase (80 mM) was used as sinalbin displacer. The 28.5 mass scale factor arose from the increase in mobile phase flow-rate (from 2 to 50 mL/min), from the higher mass of injected white mustard seed extract (from 12 to 350 g), and from the calculated productivity (from 830 mg to 26.3 g). These results demonstrate that industry scale production of glucosinolates is easily performed by SIXCPC, thus providing pure reference standards for pharmacology studies.
Danielle Julie Carrier - One of the best experts on this subject based on the ideXlab platform.
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separation of xylose oligomers from autohydrolyzed miscanthus giganteus using centrifugal Partition Chromatography
Food and Bioproducts Processing, 2015Co-Authors: Ming Hsu Chen, Danielle Julie Carrier, Kalavathy Rajan, Vijay SinghAbstract:Abstract Autohydrolysis of cellulosic materials for saccharification generates xylose-oligosaccharides (XOS), due to the partial hydrolysis of xylan. Developing an efficient method for the separation and recovery of XOS from the prehydrolyzates would provide an excellent opportunity for the better utilization of the cellulosic material and for value-added co-product production. In this study, we investigated the use of centrifugal Partition Chromatography (CPC) for the fractionation of XOS from Miscanthus × giganteus (M × G). During autohydrolysis of miscanthus biomass at 180 °C for 20 min, 63% of xylan was converted into XOS and xylose. The ensuing XOS concentrate contained up to 30% of XOS, which were distributed as 15.9% xylobiose (DP2), 5.9% xylotriose, (DP3), 5.6% xylotetraose (DP4), 0.8% xylopentaose (DP5) and 0.6% xylohexaose (DP6). The XOS concentrate was further fractionated by CPC with a solvent system composed of 4:1:4 (v/v/v) butanol:methanol:water. Using CPC techniques, 230 mg (80%) of DP2 to DP6 oligomers were fractionated from 1 g of XOS concentrate. The recoveries of individual XOS were 90.2% DP2, 64.5% DP3, 71.2% DP4, 61.9% DP5 and 68.9% DP6. The purities of DP2 to DP6 fractions were 61.9%, 63.2%, 44.5%, 31.5% and 51.3%, respectively. Presence of DP2 and DP3 in the CPC purified fractions was further validated by mass spectrometry analysis. The study provided information on fast recovery of individual XOS from crude biomass prehydrolyzate.
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separation of xylose oligomers using centrifugal Partition Chromatography with a butanol methanol water system
Journal of Industrial Microbiology & Biotechnology, 2013Co-Authors: Chingshuan Lau, Edgar C Clausen, Jackson O Lay, Jennifer Gidden, Danielle Julie CarrierAbstract:Xylose oligomers are the intermediate products of xylan depolymerization into xylose monomers. An understanding of xylan depolymerization kinetics is important to improve the conversion of xylan into monomeric xylose and to minimize the formation of inhibitory products, thereby reducing ethanol production costs. The study of xylan depolymerization requires copious amount of xylose oligomers, which are expensive if acquired commercially. Our approach consisted of producing in-house oligomer material. To this end, birchwood xylan was used as the starting material and hydrolyzed in hot water at 200 °C for 60 min with a 4 % solids loading. The mixture of xylose oligomers was subsequently fractionated by a centrifugal Partition Chromatography (CPC) with a solvent system of butanol:methanol:water in a 5:1:4 volumetric ratio. Operating in an ascending mode, the butanol-rich upper phase (the mobile phase) eluted xylose oligomers from the water-rich stationary phase at a 4.89 mL/min flow rate for a total fractionation time of 300 min. The elution of xylose oligomers occurred between 110 and 280 min. The yields and purities of xylobiose (DP 2), xylotriose (DP 3), xylotetraose (DP 4), and xylopentaose (DP 5) were 21, 10, 14, and 15 mg/g xylan and 95, 90, 89, and 68 %, respectively. The purities of xylose oligomers from this solvent system were higher than those reported previously using tetrahydrofuran:dimethyl sulfoxide:water in a 6:1:3 volumetric ratio. Moreover, the butanol-based solvent system improved overall procedures by facilitating the evaporation of the solvents from the CPC fractions, rendering the purification process more efficient.
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separation and purification of xylose oligomers using centrifugal Partition Chromatography
Journal of Industrial Microbiology & Biotechnology, 2011Co-Authors: Chingshuan Lau, Edgar C Clausen, Jackson O Lay, Jennifer Gidden, Kris Bunnell, Gregory J Thoma, Danielle Julie CarrierAbstract:Xylose oligomers, which have a prebiotic effect, have been used as additives to human and animal food. These oligomers are also the primary intermediate in hemicellulose degradation during the pretreatment of biomass. Centrifugal Partition Chromatography (CPC) was used in this study to separate and purify xylan-derived oligomers from birchwood xylan. The xylan was partially hydrolyzed to achieve varying degrees of polymerization at 130°C using 0.98% aqueous sulfuric acid for 20 min with a 2.5% solid loading. The CPC solvent system consisting of dimethyl sulfoxide (DMSO), tetrahydrofuran (THF), and water in a 1:6:3 volumetric ratio was used because of its ability to dissolve xylose oligomers of different degrees of polymerization. The CPC was operated in the ascending mode with the water- and DMSO-rich bottom phase acting as the stationary phase, while the THF-rich top phase was the eluent. This paper delineates a method for the production and purification of xylose monomer and xylose oligomers (up to xylopentaose) using CPC. The amount and purity of compounds collected from the CPC fractionation based on 1 g of birchwood xylan were 25.26 mg of xylose at 91.86% purity, 10.71 mg of xylobiose at 85.07% purity, 4.15 mg of xylotriose at 54.71% purity, 5.03 mg of xylotetraose at 38.33% purity and 3.31 mg of xylopentaose at 30.43% purity.
Jean-marc Nuzillard - One of the best experts on this subject based on the ideXlab platform.
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dereplication of depsides from the lichen pseudevernia furfuracea by centrifugal Partition Chromatography combined to 13c nuclear magnetic resonance pattern recognition
Analytica Chimica Acta, 2014Co-Authors: Sarah K Oettl, Jean-hugues Renault, Jean-marc Nuzillard, Hermann Stuppner, Jane Hubert, Judith M RollingerAbstract:Abstract Lichens produce a diversity of secondary metabolites, among them depsides comprised of two or more hydroxybenzoic acid units linked by ester, ether, or C C-bonds. During classic solid support-based purification processes, depsides are often hydrolyzed and in many cases time, consuming procedures result only in the isolation of decomposition products. In an attempt to avoid extensive purification steps while maintaining metabolite structure integrity, we propose an alternative method to identify the major depsides of a lichen crude extract (Pseudevernia furfuracea var. ceratea (Ach.) D. Hawksw., Parmeliaceae) directly within mixtures. Exploiting the acidic character of depsides and differences in polarity, the extract was fractionated by centrifugal Partition Chromatography in the pH-zone refining mode resulting in twelve simplified mixtures of depsides. After 13C nuclear magnetic resonance analysis of the produced fractions, the major molecular structures were directly identified within the fraction series by using a recently developed pattern recognition method, which combines spectral data alignment and hierarchical clustering analysis. The obtained clusters of 13C chemical shifts were assigned to their corresponding molecular structures with the help of an in-house 13C NMR chemical shift database, resulting in six unambiguously identified compounds, namely methyl β-orcinolcarboxylate (1), atranorin (2), 5-chloroatranorin (3), olivetol carboxylic acid (4), olivetoric acid (5), and olivetonide (6).
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purification of antibiotics from the biocontrol agent streptomyces anulatus s37 by centrifugal Partition Chromatography
Journal of Chromatography B, 2014Co-Authors: Olivier Couillerot, Jean-marc Nuzillard, Alix Toribio, Souad Loqman, Jane Hubert, Lea Gandner, Yedir Ouhdouch, Christophe Clement, Essaid Ait Barka, Jean-hugues RenaultAbstract:A novel actinomycete strain, Streptomyces anulatus S37, has been isolated from the rhizosphere of healthy Moroccan Vitis vinifera on the basis on its ability to promote grapevine growth and to induce natural defences against various phytopathogens. In the present work, the main bioactive metabolites produced by S. anulatus S37 were isolated. A crude n-BuOH extract of the S37 fermentation broth was firstly Partitioned in a biphasic solvent system composed of n-heptane, methanol, and water (5:1.5:3.5, v/v). The most active organic fraction (1.1g) as revealed by TLC-bioautography was subsequently separated by a two-step centrifugal Partition Chromatography procedure. The first separation was performed in the ascending mode at 6mL/min with the biphasic solvent system n-heptane, ethyl acetate, methanol and water (2:1:2:1, v/v), to finally recover 40mg of a pure compound identified as streptochlorin by NMR spectroscopy. In a second separation, the solvent system n-heptane, acetonitrile, and water (5:5:4, v/v) was used in the ascending mode at 3mL/min to purify 135mg of nigericin and 53mg of piericidin A1. Assays performed with the three compounds have confirmed their inhibitory impact on the growth of Botryris cinerea in dual confrontation and also on V. vinifera L. plantlets.
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pilot scale ion exchange centrifugal Partition Chromatography purification of sinalbin from white mustard seeds
IEEE Journal of Solid-state Circuits, 2009Co-Authors: Alix Toribio, Benoit Pinel, François De La Poype, Jean-marc Nuzillard, Leslie Boudesocque, Michel Lafosse, Jean-hugues RenaultAbstract:The purification of p-hydroxybenzylglucosinolate (sinalbin) on a multigram scale from a crude aqueous extract of white mustard seeds (Sinapis alba var. concerta) was successfully achieved by scaling up a strong ion-exchange centrifugal Partition Chromatography (SIXCPC) laboratory procedure. Thus, the one-step sinalbin purification was performed with 2.35 g of crude extract in approximately 170 min (830 mg/h) up to 70.3 g in approximately 160 min (26.3 g/h) by switching from a 200 mL laboratory scale column to a 5.7 L pilot-scale column. The required biphasic solvent system contained ethyl acetate, n-butanol, and water in 3:2:5 v/v/v proportions, Aliquat 336 (trioctylmethyl ammonium chloride) was added to the organic stationary phase (80 mM) and acted as ion-exchanger. Potassium iodide in the aqueous mobile phase (80 mM) was used as sinalbin displacer. The 28.5 mass scale factor arose from the increase in mobile phase flow-rate (from 2 to 50 mL/min), from the higher mass of injected white mustard seed extract (from 12 to 350 g), and from the calculated productivity (from 830 mg to 26.3 g). These results demonstrate that industry scale production of glucosinolates is easily performed by SIXCPC, thus providing pure reference standards for pharmacology studies.
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strong ion exchange centrifugal Partition Chromatography as an efficient method for the large scale purification of glucosinolates
Journal of Chromatography A, 2007Co-Authors: Alix Toribio, Jean-marc Nuzillard, Jean-hugues RenaultAbstract:The glucosinolates sinalbin and glucoraphanin were purified by strong ion-exchange displacement centrifugal Partition Chromatography (SIXCPC). The optimized conditions involved the biphasic solvent system ethyl acetate/n-butanol/water (3:2:5, v/v), the lipophilic anion-exchanger Aliquat 336 (trioctylmethylammonium chloride, 160 and 408 mM) and a sodium iodide solution (80 and 272 mM) as displacer. Amounts as high as 2.4 g of sinalbin and 2.6g of glucoraphanin were obtained in one step in 2.5 and 3.5h respectively, starting from 12 and 25 g of mustard and broccoli seed aqueous extracts, using a laboratory scale CPC column (200 mL inner volume).
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preparative isolation of huperzines a and b from huperzia serrata by displacement centrifugal Partition Chromatography
Journal of Chromatography A, 2007Co-Authors: Alix Toribio, Jean-marc Nuzillard, Monique Zecheshanrot, Eldra Delannay, B Richard, Karen Ple, Jean-hugues RenaultAbstract:Abstract The pH-zone refining centrifugal Partition Chromatography technique was used to separate the two acetylcholinesterase inhibitors huperzines A and B from a crude alkaloid extract of the club moss Huperzia serrata . Complete co-elution of huperzines A and B was initially observed with the well-known methyl tert -butyl ether–acetonitrile–water (4:1:5, v/v/v) solvent system with triethylamine (8 mM) as the displacer and methane sulfonic acid (6 mM) as the retainer. An efficient biphasic system was designed on the basis of solvent association that provided selectivity in the elution mode: n -heptane/ethyl acetate/ n -propanol/water (5:15:35:45, v/v/v/v). Lowering the bridge solvent content ( n -propanol) of this system increased the polarity difference between the two phases thus adapting it to the pH-zone refining mode. Thus, the purification of these compounds was achieved using the biphasic system n -heptane/ethyl acetate/ n -propanol/water (10:30:15:45, v/v/v/v) with triethylamine (8 mM) as the displacer and methane sulfonic acid (6 mM) as the retainer.
Johannes Goll - One of the best experts on this subject based on the ideXlab platform.
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trapping multiple dual mode centrifugal Partition Chromatography for the separation of intermediately eluting components operating parameter selection
Journal of Chromatography A, 2017Co-Authors: Johannes Goll, Raena Morley, Mirjana MincevaAbstract:Abstract The preparative separation of intermediately-eluting components in liquid-liquid Chromatography is commonly performed with isocratic batch injections, a technique which often leads to low yield and/or purity as a result of peak overlap. Two-column trapping multiple dual mode centrifugal Partition Chromatography, an alternative discontinuous method for the separation of a mixture into three product fractions (early-, intermediately-, and late-eluting components) at full recovery, is presented in this work. A mathematical shortcut method based on equilibrium theory assumptions is derived for the determination of the key operating parameters (i.e., step durations and number of steps). The feasibility of the technique and the accompanying short-cut method is demonstrated by proof-of-concept experiments for the separation of two paraben model mixtures.
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study of the separation limits of continuous solid support free liquid liquid Chromatography separation of capsaicin and dihydrocapsaicin by centrifugal Partition Chromatography
Journal of Chromatography A, 2013Co-Authors: Johannes Goll, Andreas Frey, Mirjana MincevaAbstract:Abstract Sequential centrifugal Partition Chromatography (sCPC) is a cyclic solid support-free liquid–liquid chromatographic process, in which a continuously introduced feed mixture is separated into two sequentially collected product streams. The few experimental demonstrations of this concept already revealed its potential for the preparative separation of pharmaceuticals and fine chemicals. In this work not only the possibilities, but also the limits of the sCPC technology are explored. A feed mixture consisting of capsaicin and dihydrocapsaicin, whose molecular structure differs in only one double bond, was selected for this purpose. The sCPC unit operating parameters needed for a complete separation of the feed mixture were selected using the recently published approach, which uses the Partition coefficient of the feed components and the hydrodynamic characteristics of the system as input data. A complete separation of capsaicin and dihydrocapsaicin with the solvent system heptane/ethyl acetate/methanol/water:1/1/1/1 (v/v/v/v) was achieved, although the separation factor was only 1.32. The sCPC unit separation performance was successfully simulated using the cell model.
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Sequential Centrifugal Partition Chromatography: A New Continuous Chromatographic Technology
Chemical Engineering & Technology, 2011Co-Authors: Elisabeth Hopmann, Johannes Goll, Mirjana MincevaAbstract:In solid-support-free liquid-liquid Chromatography, both phases can be used as a mobile phase and, moreover, their role and flow direction can be reversed during the course of the separation. This is the background of the concept of sequential centrifugal Partition Chromatography (sCPC) developed to perform a continuous separation in a cyclic manner. The feed is continuously introduced between two centrifugal Partition chromatographic columns and two products are alternately collected at the opposite ends of the columns. In this work, a method is presented to select the operating parameters of an sCPC unit for the complete separation of a binary feed mixture. The method uses, as a basis, a restricted number of experiments needed to determine the distribution equilibrium of the components to be separated and to evaluate the column hydrodynamics. The method was validated experimentally for the separation of a binary mixture of hydroquinone and pyrocatechol.