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aqueous-two-phase-system
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Modeling process partitioning of biomolecules in polymer-polymer and polymer-salt aqueous two-phase systems (ATPS) using an extended excess gibbs energy model
, Article Zeitschrift fur Physikalische Chemie ; Volume 223, Issue 3 , 2009 , Pages 263-278 ; 09429352 (ISSN) ; Taghikhani, V ; Vossough, M ; Sharif University of Technology
2009
Abstract
A new local composition model was used to study the phase behavior of polymer-polymer and polymer-salt aqueous two-phase systems. The proposed model has three terms which account for the combinatorial, the long-range and the short-range effects in solution. The Flory-Huggins and the Debye-Hückel models were used for the combinatorial and long-range contributions. The interaction parameters of the model studied in this work can be regressed using a non-liner regression between the experimental data and those obtained from the proposed model. Also, this model was applied for modeling the partitioning of biomolecules in polymer-polymer and polymer-salt aqueous two-phase systems. The results...
Theoretical and Experimental Study of the Partitioning of Cephalexin in Aqueous Two Phase System of Polymer-Salt
, M.Sc. Thesis Sharif University of Technology ; Teghikhani, Vahid (Supervisor) ; Ghotbi, Cirouc (Supervisor) ; vossoughi, Manouchehr (Supervisor)
Abstract
The aqueous two phase systems provide a suitable environment for separation and purification of biological compounds. Because both phases are water rich and biomolecule remain active in them. In this work, the partition coefficients of Cephalexin in polymer-salt aqueous two-phase systems have been measured. The experimental results were obtained at three various temperatures (37.2, 34.2 and 28.2) C and in each temperature, two salt (K2HPO4, Na3Cit) and two polymer with different molecular weight (4000, 10000) are investigated. According to the two phase analysis, the effect of different factors on tie line of systems is studied. It is observed that with increasing the PEG molecular weight,...
studying the Effect of Adding Nanoparticles in Polymer/salt Aqueous Two Phase Systems for Separating of Alpha-amylase Enzyme
,
Ph.D. Dissertation
Sharif University of Technology
;
Vossoughi, Manoochehr
(Supervisor)
;
Pazuki, Gholamreza
(Supervisor)
Abstract
The effects of adding nanoparticles in partitioning of α-amylase in polymer/salt aqueous two phase system (ATPS) was studied in this research. First the binodal curves of magnesium sulfate salt with PEGs 2000,3000,4000,6000 and 10000 at 23 ° C has been plotted and the suitable system which was PEG 6000/ magnesium sulfate has been selected for studying the partitioning of enzyme. Thereupon the partition coefficient of α-amylase was measured and then effect of adding silica and graphene oxide nanoparticles was investigated. It was observed that nanoparticles caused a dramatic increase in partition coefficient and yield recovery (of top phase). For further investigation the partitioning of...
Evaluation of Process Partitioning of Enzyme in Polymer-Salt Aqueous Two-PHase Systems
, M.Sc. Thesis Sharif University of Technology ; Alamzadeh, Iran (Supervisor) ; Vossoughi, Manouchehr (Supervisor) ; Pazuki, Gholamreza (Supervisor)
Abstract
In this research, the amount of partitioning Invertase to be evaluated in nine systems, these systems contain Peg 2000,Peg 4000 & Peg 6000 with three different salt.In first, Binodal curve for nine systems to be drown by cloudy point method, then five point be selected in each system such as sample feed. Invertase in every systems to be solved in constant weight fraction. The analysis of every phasesto be achieved by Merchuk method. For correlation data of this method to be used by Othmer-Tobias method and then using equation Mrchvk ensure the accuracy of phase analysis , analysis of the results obtained with the UV method was studied.Accuracy of UV analysis was studied by using lattice...
Measurement of Partition Coefficient of L-Lysine HCl Amino Acid in Polymer-Salt Aqueous Two-Phase Systems
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Manouchehr (Supervisor) ; Alamzadeh, Eiran (Supervisor)
Abstract
The partition coefficients of L-Lysine HCL were measured in polymer-salt aqueous two-phase systems. These systems contain polyethylene glycol with nominal molecular weight of 4000 or 10000 and two different salts (di-potassium hydrogen phosphate or tri-sodium citrate 5,5-hydrate). The experimental data were obtained at temperatures 293.15, 298.15 and 303.15 K. The effects of temperature, pH, polymer and salt concentrations, polymer molecular weight and salt type on the partitioning of L-Lysine HCL were also studied. The results showed that salt concentration has a significant effect on the partition coefficient while temperature has a low effect. The experimental partition coefficients of...
Measurement and correlation of vapor-liquid equilibria of the aqueous poly(ethylene glycol) + sodium citrate and poly(ethylene glycol) + potassium citrate systems
, Article Fluid Phase Equilibria ; Volume 262, Issue 1-2 , 2007 , Pages 137-148 ; 03783812 (ISSN) ; Zafarani Moattar, M. T ; Taghikhani, V ; Ghotbi, C ; Sharif University of Technology
Elsevier
2007
Abstract
In this study, water activities for the ternary systems of PEG6000 + sodium citrate (Na3Cit) + H2O and PEG6000 + potassium citrate (K3Cit) + H2O have been measured using an improved isopiestic method over the entire homogeneous mixing range at 298.15 K. From these measurements, values of the vapor pressure of solutions were also determined. The experimental data for the activity of water, collected in this work, were accurately correlated with local composition based models of the NRTL, modified NRTL, Wilson and modified Wilson. The results showed that these models can accurately correlate the water activity data generated in this work. © 2007 Elsevier B.V. All rights reserved
Separation and Purification of Industrial Proteins by Chromatography and Aqueous two Phase System
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Manouchehr (Supervisor) ; Seifkordi, Ali Akbar (Supervisor)
Abstract
Separation of biomolecules such as enzymes is the most important part of biotechnology process which 10-90 % of costs is for separation and purification. There are several methods for purification of bio materials and one of them is chromatography which use in enzyme purification but this method have several problem such as cost ,time consuming and scale up Because of this a suitable alternative demands for industrial separation. An alternative is aqueous two-phase systems (ATPS). In this project was studied about partial purification of alkaline protease produced by Bacillus licheniformis ATCC 21424 in aqueous two-phase system and comparison with chromatography method. an aqueous two-phase...
Simulation and Optimization of α-amylase Enzyme Purification Process
Using Column Chromatography
,
M.Sc. Thesis
Sharif University of Technology
;
Rosstaazad, Reza
(Supervisor)
Abstract
Enzymes, which are biochemical catalysts, have important applications in different industries such as food, pharmaceutical, medical, chemical identification and etc. Several methods have been used for separation of enzymes among which precipitation, chromatography and two-phase system. In this work, purification of α-amylase has been done by Ammonium Sulfate and Acetone precipitation, gel filtration based on Sephadex, and PEG-salt aqueous two-phase system. Furthermore, mass and momentum conservations’ equations were solved simultaneously to simulate the process based on the finite element method (FEM). Crude enzyme was precipitated with different saturations of ammonium sulfate and the...
Experimental Study of Partitioning of Lysozyme Enzyme in Aqueous Two-Phase Systems based on Surfactants
, M.Sc. Thesis Sharif University of Technology ; Bastani, Dariush (Supervisor) ; Vosoughi, Manochehr (Supervisor)
Abstract
In this study, aqueous two-phase systems (ATPS) containing Tween 20 as a biocompatible nonionic surfactant and three different salts (NH4HPO4, NH4CH3COO and Mg(CH3COO)2 ) were prepared and their extractive potential for Lysozyme enzyme was evaluated. These systems have surfactant-rich top phase and salt-rich bottom phase. Phase equilibrium diagrams at 23 ° C were obtained by using the cloud point method and the results were successfully fitted to the Merchuk correlation and their trends were correlated with the effective excluded volume (EEV) parameter. Afterward, the partitioning behavior of the lysozyme and its extraction efficiency in the systems of Tween 20/diammonium hydrogen phosphate,...
Partitioning of alkaline protease from Bacillus licheniformis (ATCC 21424) using PEG-K2HPO4 aqueous two-phase system
, Article Fluid Phase Equilibria ; Volume 337 , January , 2013 , Pages 1-5 ; 03783812 (ISSN) ; Pazuki, G. R ; Vossoughi, M ; Mirkhani, S. A ; Seifkordi, A. A ; Sharif University of Technology
2013
Abstract
An aqueous two-phase system (ATPS) containing polyethylene glycol (PEG) and potassium phosphate (K2HPO4) was used for partitioning and partial purification of alkaline protease produced by Bacillus licheniformis ATCC 21424. The effect of PEG molar mass, pH and concentration of NaCl salt addition on partition coefficient, yield and purification factor (PF) for ATPS were studied. The highest partition coefficient (5.3) was achieved in an ATPS of 25% (w/w) PEG 10,000 (g/mol) and 10% (w/w) NaCl at pH 9. Cation and anion exchange chromatography was employed for purification of alkaline protease from protein mixture and the yield and PF for enzyme fractions were obtained to make a comparison...
Liquid-liquid phase equilibrium of MgSO4 and PEG1500 aqueous two-phase system
, Article Physics and Chemistry of Liquids ; Volume 48, Issue 6 , 2010 , Pages 764-772 ; 00319104 (ISSN) ; Pazuki, G. R ; Taghikhani, V ; Vossoughi, M ; Ghotbi, C ; Sharif University of Technology
2010
Abstract
In this work, PEG 1500, MgSO4 and water were used to create an aqueous two-phase system and the effect of temperature was surveyed by obtaining binodal data and equilibrium data at 35, 40 and 45 C; compositions of mixture were obtained by atomic absorption spectrometer and refractometery method. Results showed that with increasing temperature, the solution tends to attain a two-phase region and the slope and length of tie lines increases. Modified Wilson equation was used to correlate this system, adjustable parameters were evaluated directly from experimental data and good agreement with experimental data was obtained. The overall average relative deviation was found to be less than 6%
Measurement of partition coefficients of β-amylase and amyloglucosidase enzymes in aqueous two-phase systems containing poly(ethylene glycol) and Na2SO4/KH2PO4 at different temperatures
, Article Fluid Phase Equilibria ; Volume 292, Issue 1-2 , May , 2010 , Pages 80-86 ; 03783812 (ISSN) ; Taghikhani, V ; Vossoughi, M ; Safe kordi, A. A ; Alemzadeh, I ; Pazuki, G. R ; Sharif University of Technology
2010
Abstract
In this research, partitioning of β-amylase and amyloglucosidase was investigated in polymer-salt aqueous two-phase systems containing poly(ethylene glycol) (PEG) with different molecular weights such as 4000, 6000 and 10,000 and Na2SO4 or KH2PO4. The experimental partition coefficients were measured at T = (298.5, 301.5, 303.5, 305.5 and 308) K. The results showed that the concentration of salt in feed had more effect on partition coefficients of β-amylase and amyloglucosidase in aqueous two-phase systems than the concentration of polymer in initial feed. Also, the results indicated that temperature had a small effect on partitioning of β-amylase and amyloglucosidase enzymes. The partition...
Experimental Study and Thermodynamic Modeling of Process Partitioning of Penicillin in Polymer-Salt Aqueous Two-Phase Systems
, Ph.D. Dissertation Sharif University of Technology ; Taghikhani, Vahid (Supervisor) ; Vossoughi, Manouchehr (Supervisor)
Abstract
In this research, the partitioning of Penicillin G-Acylase in aqueous two-phase systems (ATPS) containing poly ethylene glycol (PEG) 20000 or 35000 and potassium di-hydrogen phosphate (KH2PO4) or sodium citrate (C6H5Na3O7.5H2O) is measured at three temperature (301.2, 307.2 and 310.2) K. The effects of temperature, polymer molecular weight, polymer and salt concentrations on partitioning of Penicillin G in the aqueous two-phase systems are studied. The experimental data showed that composition of salt has a large effect on partitioning of Penicillin G in ATPS and temperature of system has small effect on the partitioning. The modified local composition model was used to obtain the activity...
Experimental Study and Prediction of Vancomycin Partitioningin Surfactant-Salt Aqueous Two-Phase Systems
, M.Sc. Thesis Sharif University of Technology ; Vosughi, Manouchehr (Supervisor) ; Rashtchian, Davood (Supervisor) ; Pazuki, Gholamreza (Supervisor)
Abstract
In the past years, upstream processes have been receiving a considerable R&D investment and commercial attention. The downstream processes have, however, been overlooked causing a production bottleneck that is shifting the costs of production from up to downstream. The need to develop more efficient and cost-effective separation and purification processes is, thus, crucial in order to improve process efficiency and economics keeping the required high standards of quality for market approval. In this research, promising aqueous two-phase systems (ATPS) containing Tween 20 as a quite biocompatible non-ionic surfactant and different salts (K3Citrate and NaH2PO4) were prepared and their...
Experimental study and mathematical modeling of partitioning of β-amylase and amyloglucosidase in PEG-salt aqueous two-phase systems
, Article Journal of Chemical and Engineering Data ; Volume 55, Issue 11 , 2010 , Pages 4968-4975 ; 00219568 (ISSN) ; Vossoughi, M ; Taghikhani, V ; Safekordi, A. A ; Alemzadeh, I ; Sharif University of Technology
2010
Abstract
In this study, the partitioning of β-amylase in aqueous two-phase systems (ATPS) containing polyethylene glycol (PEG) with a molar mass of 6000 and 10 000 and KH 2PO 4 at T = (301.65 and 304.65) K was experimentally studied. In addition, the partitioning of amyloglucosidase in ATPS containing polyethylene glycol with molar mass of 4000, 6000, and 10 000 in the presence of Na 2SO 4 at T = (301.65 and 305.65) K was investigated. The effects of molar mass of PEG, temperature, mass fractions of salt, and the length of the tie line on partition coefficients of the enzymes were also studied. The experimental results showed that while the partition coefficients of enzymes decrease with increasing...
Measurement and modeling process partitioning of cephalexin antibiotic in aqueous two-phase systems containing poly(ethylene glycol) 4000, 10000 and K2HPO4, Na3Citrate
, Article Journal of Chemical and Engineering Data ; Volume 54, Issue 8 , 2009 , Pages 2239-2244 ; 00219568 (ISSN) ; Pazuki, G. R ; Taghikhani, V ; Vossoughi, M ; Ghotbi, C ; Sharif University of Technology
2009
Abstract
In this work, the partition coefficients of Cephalexin in aqueous two-phase systems containing PEG [poly(ethylene glycol)] 4000, 10000 and K 2HPO4, Na3Citrate (C6H 5Na3O7 5, 5H2O) have been measured. The experimental data were obtained in a wide range of temperatures, (28.2 to 37.2) °C. The effects of temperature, pH, polymer concentration, polymer molecular weight, and salt concentration on the partitioning of Cephalexin were also studied. The results showed that salt concentration has a large effect on the partition coefficient, and temperature has an almost negligible effect. The Chen-NRTL Gibbs energy model was used to correlate the experimental results. © 2009 American Chemical Society
Prediction of the partition coefficients of biomolecules in polymer-polymer aqueous two-phase systems using the artificial neural network model
, Article Particulate Science and Technology ; Volume 28, Issue 1 , 2010 , Pages 67-73 ; 02726351 (ISSN) ; Taghikhani, V ; Vossoughi, M ; Sharif University of Technology
Abstract
In this work, an artificial neural network model was used to obtain the partition coefficients of biomolecules in polymer-polymer aqueous two-phase systems. In the artificial neural network, the partition coefficient of a biomolecule depends on the difference between concentrations of poly (ethylene glycol), dextran in the top and bottom phases, temperature and molecular weights of poly (ethylene glycol), dextran, and the biomolecule. The network topology is optimized and the (6-1-1) architecture is found using optimization of an objective function with sequential quadratic programming (SQP) method for 450 experimental data points. The results obtained from the neural network of the...
Partitioning of l-lysine monohydrochloride in aqueous two-phase systems of poly(ethylene glycol) and dipotassium hydrogen phosphate or trisodium citrate 5-hydrate
, Article Journal of Chemical and Engineering Data ; Volume 55, Issue 9 , 2010 , Pages 3005-3009 ; 00219568 (ISSN) ; Pazuki, G ; Vossoughi, M ; Alemzadeh, I ; Sharif University of Technology
2010
Abstract
The partition constants of l-lysine HCl were measured in polymer-salt aqueous two-phase systems. These systems contain poly(ethylene glycol) with a nominal molecular weight of 4000 or 10000 and two different salts (dipotassium hydrogen phosphate or trisodium citrate 5-hydrate). The experimental data were obtained at temperatures of (293.15, 298.15, and 303.15) K. The effects of temperature, pH, polymer and salt concentrations, polymer molecular weight, and salt type on the partitioning of l-lysine HCl were also studied. The results showed that salt concentration has a significant effect on the partition constant while temperature has less effect. The Diamond and Hsu model was used to...
Partitioning of penicillin G acylase in aqueous two-phase systems of poly(ethylene glycol) 20000 or 35000 and potassium dihydrogen phosphate or sodium citrate
, Article Journal of Chemical and Engineering Data ; Volume 55, Issue 1 , 2010 , Pages 243-248 ; 00219568 (ISSN) ; Vossoughi, M ; Taghikhani, V ; Sharif University of Technology
Abstract
The partitioning of penicillin G acylase in aqueous two-phase systems (ATPS's) containing poly(ethylene glycol) (PEG) 20000 or 35000 and potassium dihydrogen phosphate (KH2PO4) or sodium citrate (C 6H5Na3O7 ·5H2O) has been measured at three temperatures, (301.2, 307.2, and 310.2) K. The effects of temperature, polymer molecular weight, and polymer and salt concentrations on the partitioning of penicillin G in the ATPS were studied. The experimental data showed that the composition of salt has a large effect on partitioning of penicillin G in ATPS, and the temperature of the system has a small effect on the partitioning. The UNIFAC-FV group contribution model (Pazuki et al., Ind. Eng. Chem....
Turnip (brassica rapa) peroxidase: Purification and characterization
, Article Industrial and Engineering Chemistry Research ; Volume 48, Issue 23 , Volume 48, Issue 23 , 2009 , Pages 10614-10618 ; 08885885 (ISSN) ; Ghaemmaghami, F ; Alemzadeh, I ; Sharif University of Technology
ACS
2009
Abstract
Partial purification of plant peroxidase from turnip (Brassica rapa) was optimized. Aqueous two phase system and precipitation by ammonium sulfate (as two parallel purification methods) were used. Polyethylene glycol/ammonium sulfate/NaCl (25:7:3%, w/v) system followed by gel-filtration chromatography gave a purification factor of about 36 fold. On the other hand, ammonium sulfate precipitation (60-80% deg) followed by gel filtration gave only about 13 purification fold. Hence, the aqueous two-phase system was more efficient and useful method as a primary purification step since it was less laborious, less time-consuming, and led to more purification factor. The partially purified turnip...