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Fumio Hirata - One of the best experts on this subject based on the ideXlab platform.
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Partial Molar Volume of nonionic surfactants in aqueous solution studied by the KB/3D-RISM–KH theory
Journal of Molecular Liquids, 2016Co-Authors: M F Holovko, Andriy Kovalenko, Fumio HirataAbstract:Abstract Description of self-assembly by means of atomistic models without coarse-graining and empirical adjustment is the most challenging problem in statistical mechanics of liquids. Partial Molar Volume (PMV) is a thermodynamic property related to effective solvation forces spontaneously driving self-assembly of amphiphilic molecules in solution. We calculate the PMV of several ethylene glycol derivatives, in particular, alkyl polyoxyethylene ethers H(CH 2 ) m − 1 (CH 2 OCH 2 ) n CH 2 OH commonly known as C m E n nonionic surfactants, in aqueous solution at infinite dilution by using the Kirkwood–Buff (KB) equation and the three-dimensional reference interaction site model with the Kovalenko–Hirata closure relation (3D-RISM–KH) integral equation theory of molecular liquids. Special attention is paid to the infinite dilution case since direct measurement of PMV of monomeric surfactants is hindered by their very low critical micelle concentration (cmc). The PMVs obtained from the KB/3D-RISM–KH approach are in good qualitative agreement with experimental data for ethylene glycol derivatives in water at 5; 25; and 45 °C.
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Partial Molar Volume of nonionic surfactants in aqueous solution studied by the kb 3d rism kh theory
Journal of Molecular Liquids, 2016Co-Authors: M F Holovko, Andriy Kovalenko, Fumio HirataAbstract:Abstract Description of self-assembly by means of atomistic models without coarse-graining and empirical adjustment is the most challenging problem in statistical mechanics of liquids. Partial Molar Volume (PMV) is a thermodynamic property related to effective solvation forces spontaneously driving self-assembly of amphiphilic molecules in solution. We calculate the PMV of several ethylene glycol derivatives, in particular, alkyl polyoxyethylene ethers H(CH 2 ) m − 1 (CH 2 OCH 2 ) n CH 2 OH commonly known as C m E n nonionic surfactants, in aqueous solution at infinite dilution by using the Kirkwood–Buff (KB) equation and the three-dimensional reference interaction site model with the Kovalenko–Hirata closure relation (3D-RISM–KH) integral equation theory of molecular liquids. Special attention is paid to the infinite dilution case since direct measurement of PMV of monomeric surfactants is hindered by their very low critical micelle concentration (cmc). The PMVs obtained from the KB/3D-RISM–KH approach are in good qualitative agreement with experimental data for ethylene glycol derivatives in water at 5; 25; and 45 °C.
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theoretical study of the Partial Molar Volume change associated with the pressure induced structural transition of ubiquitin
Protein Science, 2007Co-Authors: T Imai, Andriy Kovalenko, Shusaku Ohyama, Fumio HirataAbstract:The Partial Molar Volume (PMV) change associated with the pressure-induced structural transition of ubiquitin is analyzed by the three-dimensional reference interaction site model (3D-RISM) theory of molecular solvation. The theory predicts that the PMV decreases upon the structural transition, which is consistent with the experimental observation. The Volume decomposition analysis demonstrates that the PMV reduction is primarily caused by the decrease in the Volume of structural voids in the protein, which is Partially canceled by the Volume expansion due to the hydration effects. It is found from further analysis that the PMV reduction is ascribed substantially to the penetration of water molecules into a specific part of the protein. Based on the thermodynamic relation, this result implies that the water penetration causes the pressure-induced structural transition. It supports the water penetration model of pressure denaturation of proteins proposed earlier.
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Theoretical study of the Partial Molar Volume change associated with the pressure‐induced structural transition of ubiquitin
Protein Science, 2007Co-Authors: T Imai, Andriy Kovalenko, Shusaku Ohyama, Fumio HirataAbstract:The Partial Molar Volume (PMV) change associated with the pressure-induced structural transition of ubiquitin is analyzed by the three-dimensional reference interaction site model (3D-RISM) theory of molecular solvation. The theory predicts that the PMV decreases upon the structural transition, which is consistent with the experimental observation. The Volume decomposition analysis demonstrates that the PMV reduction is primarily caused by the decrease in the Volume of structural voids in the protein, which is Partially canceled by the Volume expansion due to the hydration effects. It is found from further analysis that the PMV reduction is ascribed substantially to the penetration of water molecules into a specific part of the protein. Based on the thermodynamic relation, this result implies that the water penetration causes the pressure-induced structural transition. It supports the water penetration model of pressure denaturation of proteins proposed earlier.
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theoretical study of the cosolvent effect on the Partial Molar Volume change of staphylococcal nuclease associated with pressure denaturation
Journal of Physical Chemistry B, 2007Co-Authors: Takeshi Yamazaki, Fumio Hirata, T Imai, Andriy KovalenkoAbstract:We explain the molecular mechanism of the effect of urea and glycerol cosolvents on the Partial Molar Volume (PMV) change associated with the pressure denaturation of staphylococcal nuclease (SNase...
T Imai - One of the best experts on this subject based on the ideXlab platform.
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uncovering the physical origin of the difference between aliphatic chain and aromatic ring in the hydrophobic effects on Partial Molar Volume
Journal of Chemical Physics, 2008Co-Authors: T Imai, Seiji Sawamura, Yu Hisadomi, Yoshihiro TaniguchiAbstract:The Partial Molar Volume changes in the transfer of several hydrophobic molecules, which are composed of aromatic rings and an aliphatic chain of different lengths, from carbon tetrachloride to water (ΔVhyd) are calculated using the three-dimensional interaction site model theory of molecular solvation. The theory reproduces recent experimental observations: the addition of a methyl group decreases ΔVhyd; in contrast, the addition of an aromatic ring increases ΔVhyd. The discrepancy is found to originate from the difference between chain and ring structures rather than that between aliphaticity and aromaticity. Furthermore, a general rule of the variation in ΔVhyd due to the addition of a hydrocarbon is found through the theoretical analysis. An outward addition at the trans position, which is to form chain structure, decreases ΔVhyd, while an inward addition at the cis position, which is to form ring structure, increases ΔVhyd. This is explained in terms of solvent packing rather than the so-called hydro...
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molecular theory of Partial Molar Volume and its applications to biomolecular systems
Condensed Matter Physics, 2007Co-Authors: T ImaiAbstract:The Partial Molar Volume (PMV) is a thermodynamic quantity which contains important information about the solute-solvent interactions as well as the solute structure in solution. Additionally, the PMV is the most essential quantity in the analysis of the pressure effect on chemical reactions. This article reviews the recent developments in molecular theories of the PMV, especially the reference interaction site model (RISM) theory of molecular liquids and its three-dimensional generalization version (3D-RISM), which are combined with the Kirkwood-Buff solution theory to calculate the PMV. This article also introduces our recent applications of the theory to some interesting issues concerning the PMV of biomolecules. In addition, theoretical representations of the effects of intramolecular fluctuation on the PMV, which are significant for biomacromolecules, are briefly discussed.
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theoretical study of the Partial Molar Volume change associated with the pressure induced structural transition of ubiquitin
Protein Science, 2007Co-Authors: T Imai, Andriy Kovalenko, Shusaku Ohyama, Fumio HirataAbstract:The Partial Molar Volume (PMV) change associated with the pressure-induced structural transition of ubiquitin is analyzed by the three-dimensional reference interaction site model (3D-RISM) theory of molecular solvation. The theory predicts that the PMV decreases upon the structural transition, which is consistent with the experimental observation. The Volume decomposition analysis demonstrates that the PMV reduction is primarily caused by the decrease in the Volume of structural voids in the protein, which is Partially canceled by the Volume expansion due to the hydration effects. It is found from further analysis that the PMV reduction is ascribed substantially to the penetration of water molecules into a specific part of the protein. Based on the thermodynamic relation, this result implies that the water penetration causes the pressure-induced structural transition. It supports the water penetration model of pressure denaturation of proteins proposed earlier.
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Theoretical study of the Partial Molar Volume change associated with the pressure‐induced structural transition of ubiquitin
Protein Science, 2007Co-Authors: T Imai, Andriy Kovalenko, Shusaku Ohyama, Fumio HirataAbstract:The Partial Molar Volume (PMV) change associated with the pressure-induced structural transition of ubiquitin is analyzed by the three-dimensional reference interaction site model (3D-RISM) theory of molecular solvation. The theory predicts that the PMV decreases upon the structural transition, which is consistent with the experimental observation. The Volume decomposition analysis demonstrates that the PMV reduction is primarily caused by the decrease in the Volume of structural voids in the protein, which is Partially canceled by the Volume expansion due to the hydration effects. It is found from further analysis that the PMV reduction is ascribed substantially to the penetration of water molecules into a specific part of the protein. Based on the thermodynamic relation, this result implies that the water penetration causes the pressure-induced structural transition. It supports the water penetration model of pressure denaturation of proteins proposed earlier.
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theoretical study of the cosolvent effect on the Partial Molar Volume change of staphylococcal nuclease associated with pressure denaturation
Journal of Physical Chemistry B, 2007Co-Authors: Takeshi Yamazaki, Fumio Hirata, T Imai, Andriy KovalenkoAbstract:We explain the molecular mechanism of the effect of urea and glycerol cosolvents on the Partial Molar Volume (PMV) change associated with the pressure denaturation of staphylococcal nuclease (SNase...
Andriy Kovalenko - One of the best experts on this subject based on the ideXlab platform.
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Partial Molar Volume of nonionic surfactants in aqueous solution studied by the kb 3d rism kh theory
Journal of Molecular Liquids, 2016Co-Authors: M F Holovko, Andriy Kovalenko, Fumio HirataAbstract:Abstract Description of self-assembly by means of atomistic models without coarse-graining and empirical adjustment is the most challenging problem in statistical mechanics of liquids. Partial Molar Volume (PMV) is a thermodynamic property related to effective solvation forces spontaneously driving self-assembly of amphiphilic molecules in solution. We calculate the PMV of several ethylene glycol derivatives, in particular, alkyl polyoxyethylene ethers H(CH 2 ) m − 1 (CH 2 OCH 2 ) n CH 2 OH commonly known as C m E n nonionic surfactants, in aqueous solution at infinite dilution by using the Kirkwood–Buff (KB) equation and the three-dimensional reference interaction site model with the Kovalenko–Hirata closure relation (3D-RISM–KH) integral equation theory of molecular liquids. Special attention is paid to the infinite dilution case since direct measurement of PMV of monomeric surfactants is hindered by their very low critical micelle concentration (cmc). The PMVs obtained from the KB/3D-RISM–KH approach are in good qualitative agreement with experimental data for ethylene glycol derivatives in water at 5; 25; and 45 °C.
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Partial Molar Volume of nonionic surfactants in aqueous solution studied by the KB/3D-RISM–KH theory
Journal of Molecular Liquids, 2016Co-Authors: M F Holovko, Andriy Kovalenko, Fumio HirataAbstract:Abstract Description of self-assembly by means of atomistic models without coarse-graining and empirical adjustment is the most challenging problem in statistical mechanics of liquids. Partial Molar Volume (PMV) is a thermodynamic property related to effective solvation forces spontaneously driving self-assembly of amphiphilic molecules in solution. We calculate the PMV of several ethylene glycol derivatives, in particular, alkyl polyoxyethylene ethers H(CH 2 ) m − 1 (CH 2 OCH 2 ) n CH 2 OH commonly known as C m E n nonionic surfactants, in aqueous solution at infinite dilution by using the Kirkwood–Buff (KB) equation and the three-dimensional reference interaction site model with the Kovalenko–Hirata closure relation (3D-RISM–KH) integral equation theory of molecular liquids. Special attention is paid to the infinite dilution case since direct measurement of PMV of monomeric surfactants is hindered by their very low critical micelle concentration (cmc). The PMVs obtained from the KB/3D-RISM–KH approach are in good qualitative agreement with experimental data for ethylene glycol derivatives in water at 5; 25; and 45 °C.
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octanol water partition coefficient from 3d rism kh molecular theory of solvation with Partial Molar Volume correction
Journal of Physical Chemistry B, 2015Co-Authors: Wenjuan Huang, Nikolay Blinov, Andriy KovalenkoAbstract:The octanol–water partition coefficient is an important physical–chemical characteristic widely used to describe hydrophobic/hydrophilic properties of chemical compounds. The partition coefficient is related to the transfer free energy of a compound from water to octanol. Here, we introduce a new protocol for prediction of the partition coefficient based on the statistical-mechanical, 3D-RISM-KH molecular theory of solvation. It was shown recently that with the compound–solvent correlation functions obtained from the 3D-RISM-KH molecular theory of solvation, the free energy functional supplemented with the correction linearly related to the Partial Molar Volume obtained from the Kirkwood–Buff/3D-RISM theory, also called the “universal correction” (UC), provides accurate prediction of the hydration free energy of small compounds, compared to explicit solvent molecular dynamics [Palmer, D. S.; J. Phys.: Condens. Matter 2010, 22, 492101]. Here we report that with the UC reparametrized accordingly this theory...
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theoretical study of the Partial Molar Volume change associated with the pressure induced structural transition of ubiquitin
Protein Science, 2007Co-Authors: T Imai, Andriy Kovalenko, Shusaku Ohyama, Fumio HirataAbstract:The Partial Molar Volume (PMV) change associated with the pressure-induced structural transition of ubiquitin is analyzed by the three-dimensional reference interaction site model (3D-RISM) theory of molecular solvation. The theory predicts that the PMV decreases upon the structural transition, which is consistent with the experimental observation. The Volume decomposition analysis demonstrates that the PMV reduction is primarily caused by the decrease in the Volume of structural voids in the protein, which is Partially canceled by the Volume expansion due to the hydration effects. It is found from further analysis that the PMV reduction is ascribed substantially to the penetration of water molecules into a specific part of the protein. Based on the thermodynamic relation, this result implies that the water penetration causes the pressure-induced structural transition. It supports the water penetration model of pressure denaturation of proteins proposed earlier.
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Theoretical study of the Partial Molar Volume change associated with the pressure‐induced structural transition of ubiquitin
Protein Science, 2007Co-Authors: T Imai, Andriy Kovalenko, Shusaku Ohyama, Fumio HirataAbstract:The Partial Molar Volume (PMV) change associated with the pressure-induced structural transition of ubiquitin is analyzed by the three-dimensional reference interaction site model (3D-RISM) theory of molecular solvation. The theory predicts that the PMV decreases upon the structural transition, which is consistent with the experimental observation. The Volume decomposition analysis demonstrates that the PMV reduction is primarily caused by the decrease in the Volume of structural voids in the protein, which is Partially canceled by the Volume expansion due to the hydration effects. It is found from further analysis that the PMV reduction is ascribed substantially to the penetration of water molecules into a specific part of the protein. Based on the thermodynamic relation, this result implies that the water penetration causes the pressure-induced structural transition. It supports the water penetration model of pressure denaturation of proteins proposed earlier.
Mamata Mukhopadhyay - One of the best experts on this subject based on the ideXlab platform.
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Partial Molar Volume fraction of solvent in binary co2 solvent solution for solid solubility predictions
Journal of Supercritical Fluids, 2004Co-Authors: Mamata Mukhopadhyay, Sameer V DalviAbstract:Prediction of solid solute solubility in an organic solvent with dissolution of dense CO2 as antisolvent is important for the design of antisolvent crystallization processes. A new model is proposed in this work to predict the mole fraction of a pure solid solute in a ternary (CO2–solvent–solid) system at solid–liquid equilibrium. This is based on the hypothesis that CO2 molecules cluster around the solvent molecules at high values of CO2 mole fraction. As a result the solvent molecules proportionately lose their affinity for the solid solute molecules. Accordingly the solid mole fraction in a solution is considered to be proportional to the Partial Molar Volume fraction (PMVF) of the solvent in the binary (CO2–solvent) liquid solution or the solvent's contribution to the Molar Volume of the binary system. This model enables prediction of the liquid phase composition of the ternary system using only the binary information. The model has been validated, by predicting the solid solubility in various organic solvents, in good agreement with the corresponding experimental data from the literature, for several solids, such as β-carotene, cholesterol, acetaminophen, as well as naphthalene, phenanthrene and salicylic acid. The performance of this model is found to be better than an earlier method, which uses the Partial Molar Volume (PMV) of solvent in the CO2–solvent mixture.
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Partial Molar Volume fraction of solvent in binary (CO2–solvent) solution for solid solubility predictions
Journal of Supercritical Fluids, 2004Co-Authors: Mamata Mukhopadhyay, Sameer V DalviAbstract:Prediction of solid solute solubility in an organic solvent with dissolution of dense CO2 as antisolvent is important for the design of antisolvent crystallization processes. A new model is proposed in this work to predict the mole fraction of a pure solid solute in a ternary (CO2–solvent–solid) system at solid–liquid equilibrium. This is based on the hypothesis that CO2 molecules cluster around the solvent molecules at high values of CO2 mole fraction. As a result the solvent molecules proportionately lose their affinity for the solid solute molecules. Accordingly the solid mole fraction in a solution is considered to be proportional to the Partial Molar Volume fraction (PMVF) of the solvent in the binary (CO2–solvent) liquid solution or the solvent's contribution to the Molar Volume of the binary system. This model enables prediction of the liquid phase composition of the ternary system using only the binary information. The model has been validated, by predicting the solid solubility in various organic solvents, in good agreement with the corresponding experimental data from the literature, for several solids, such as β-carotene, cholesterol, acetaminophen, as well as naphthalene, phenanthrene and salicylic acid. The performance of this model is found to be better than an earlier method, which uses the Partial Molar Volume (PMV) of solvent in the CO2–solvent mixture.
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Partial Molar Volume reduction of solvent for solute crystallization using carbon dioxide as antisolvent
Journal of Supercritical Fluids, 2003Co-Authors: Mamata MukhopadhyayAbstract:Abstract The gas antisolvent crystallization (GASC) process using dense carbon dioxide (CO 2 ) as antisolvent is particularly useful for purification and micronization of thermo-labile bioactive solid substances. Conventionally, the GASC process is characterized by the relative total Volume expansion or the relative Molar Volume expansion of the solution. A new criterion is proposed in this work in terms of the relative Partial Molar Volume reduction (RPMVR) of the solvent for selection of the solvent and the optimum process condition for the GASC process, as it directly gives a measure of the fraction of the dissolved solute crystallized. The solute solubility is proportional to the Partial Molar Volume of the solvent, v 2 which drastically decreases at a high CO 2 dissolution. This is attributed to clustering of CO 2 molecules around the solvent molecules causing the loss of solvent power. This results in the desired antisolvent effect for lowering the solute solubility. v 2 has been calculated for a large number of solvent–CO 2 liquid mixtures using the Peng–Robinson equation of state. It has been observed that v 2 drastically reduces at a high value of x 1 , irrespective of the fact whether the solvent density is higher or lower than that of the CO 2 . The solute solubility has been predicted from its value at the ambient pressure and the ratio of the Partial Molar Volumes of the solvent with and without CO 2 dissolved in it. The predicted solubility of β-carotene in ethyl acetate with variation of x 1 at 298 K has been found to compare well with the experimentally observed trend of the GASC process.
Masataka Nagaoka - One of the best experts on this subject based on the ideXlab platform.
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influence of hydrostatic pressure on dynamics and spatial distribution of protein Partial Molar Volume time resolved surficial kirkwood buff approach
Journal of Physical Chemistry B, 2010Co-Authors: Isseki Yu, Tomohiro Tasaki, Kyoko Nakada, Masataka NagaokaAbstract:The influence of hydrostatic pressure on the Partial Molar Volume (PMV) of the protein apomyoglobin (AMb) was investigated by all-atom molecular dynamics (MD) simulations. Using the time-resolved Kirkwood−Buff (KB) approach, the dynamic behavior of the PMV was identified. The simulated time average value of the PMV and its reduction by 3000 bar pressurization correlated with experimental data. In addition, with the aid of the surficial KB integral method, we obtained the spatial distributions of the components of PMV to elucidate the detailed mechanism of the PMV reduction. New R-dependent PMV profiles identified the regions that increase or decrease the PMV under the high pressure condition. The results indicate that besides the hydration in the vicinity of the protein surface, the outer space of the first hydration layer also significantly influences the total PMV change. These results provide a direct and detailed picture of pressure induced PMV reduction.
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intrinsic alterations in the Partial Molar Volume on the protein denaturation surficial kirkwood buff approach
Journal of Physical Chemistry B, 2009Co-Authors: Isseki Yu, Masayoshi Takayanagi, Masataka NagaokaAbstract:The Partial Molar Volume (PMV) of the protein chymotrypsin inhibitor 2 (CI2) was calculated by all-atom MD simulation. Denatured CI2 showed almost the same average PMV value as that of native CI2. This is consistent with the phenomenological question of the protein Volume paradox. Furthermore, using the surficial Kirkwood−Buff approach, spatial distributions of PMV were analyzed as a function of the distance from the CI2 surface. The profiles of the new R-dependent PMV indicate that, in denatured CI2, the reduction in the solvent electrostatic interaction Volume is canceled out mainly by an increment in thermal Volume in the vicinity of its surface. In addition, the PMV of the denatured CI2 was found to increase in the region in which the number density of water atoms is minimum. These results provide a direct and detailed picture of the mechanism of the protein Volume paradox suggested by Chalikian et al.
