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Malik R, Das B, Chandra A. Theoretical Two Dimensional Infrared Spectroscopy of Aqueous Solutions of tert-Butyl Alcohol: Variation of the Dynamics of Spectral Diffusion along the Percolation Transition. J Phys Chem B 2023; 127:4099-4111. [PMID: 37126459 DOI: 10.1021/acs.jpcb.2c08916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Binary mixtures of water and tert-butyl alcohol (TBA) are known to exhibit the so-called percolation transition where small clusters of TBA molecules span into large aggregates beyond a threshold concentration of the alcohol. In the present study, we have investigated the linear and two-dimensional infrared spectral features of aqueous solutions of TBA for varying concentration of the alcohol along the percolation transition. The percolation transition is characterized through calculations of intermolecular radial distribution functions and average size of the largest cluster of TBA molecules. It is found that, with variation of alcohol concentration, the radial distribution functions of the central carbon atoms of TBA molecules show a nonmonotonic change in the height of the first peak and also the size of the largest cluster of TBA molecules show a jump in the increase of its size for TBA mole fraction between 0.04 and 0.06 corresponding to a transition from smaller clusters to larger spanning aggregates. However, it is found that the linear infrared spectrum of water does not exhibit any noticeable changes on variation of TBA concentration along the percolation transition. Subsequently, two-dimensional infrared (2DIR) spectra and vibrational frequency time correlation function of water are calculated for all the TBA-water solutions considered in this study. The spectral diffusion of water calculated from 2DIR is found to slow down with increase of the TBA concentration. The time scales of spectral diffusion of water, as characterized by the relaxation of frequency time correlation function, 2DIR metric of central line slope, and also the hydrogen bond time correlation functions, are found to exhibit a noticeable jump along the percolation transition. The hydrophilic group of TBA is found to retard the water dynamics more effectively than the hydrophobic groups. Also, the jump in the dynamical slowdown along the percolation transition is found to be more significant for water molecules at the hydrophilic sites.
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Affiliation(s)
- Ravi Malik
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Banshi Das
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Amalendu Chandra
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
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2
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Kokic Males V, Požar M. How SGLT2 inhibitors interact with metformin? A molecular dynamics study. MOLECULAR SIMULATION 2023. [DOI: 10.1080/08927022.2023.2196346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2023]
Affiliation(s)
- Visnja Kokic Males
- University Department for Health Studies, University of Split, Split, Croatia
| | - Martina Požar
- Faculty of Science, University of Split, Split, Croatia
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Macchiagodena M, Bassu G, Vettori I, Fratini E, Procacci P, Pagliai M. 2-Butanol Aqueous Solutions: A Combined Molecular Dynamics and Small/Wide-Angle X-ray Scattering Study. J Phys Chem A 2022; 126:8826-8833. [DOI: 10.1021/acs.jpca.2c05708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Marina Macchiagodena
- Dipartimento di Chimica “Ugo Schiff”, Università degli Studi di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino, Firenze, Italy
| | - Gavino Bassu
- Dipartimento di Chimica “Ugo Schiff”, Università degli Studi di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino, Firenze, Italy
- Consorzio per lo Sviluppo dei Sistemi a Grande Interfase (CSGI), Via della Lastruccia 3, 50019 Sesto Fiorentino, Firenze, Italy
| | - Irene Vettori
- Dipartimento di Chimica “Ugo Schiff”, Università degli Studi di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino, Firenze, Italy
- Consorzio per lo Sviluppo dei Sistemi a Grande Interfase (CSGI), Via della Lastruccia 3, 50019 Sesto Fiorentino, Firenze, Italy
| | - Emiliano Fratini
- Dipartimento di Chimica “Ugo Schiff”, Università degli Studi di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino, Firenze, Italy
- Consorzio per lo Sviluppo dei Sistemi a Grande Interfase (CSGI), Via della Lastruccia 3, 50019 Sesto Fiorentino, Firenze, Italy
| | - Piero Procacci
- Dipartimento di Chimica “Ugo Schiff”, Università degli Studi di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino, Firenze, Italy
| | - Marco Pagliai
- Dipartimento di Chimica “Ugo Schiff”, Università degli Studi di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino, Firenze, Italy
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4
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A subtle interplay between hydrophilic and hydrophobic hydration governs butanol (de)mixing in water. Chem Phys Lett 2022. [DOI: 10.1016/j.cplett.2022.140080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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5
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Tsarkova LA, Gurkov TD. Volatile surfactants: Characterization and areas of application. Curr Opin Colloid Interface Sci 2022. [DOI: 10.1016/j.cocis.2022.101592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Baksi A, Biswas R. Dynamical Anomaly of Aqueous Amphiphilic Solutions: Connection to Solution H-Bond Fluctuation Dynamics? ACS OMEGA 2022; 7:10970-10984. [PMID: 35415359 PMCID: PMC8991915 DOI: 10.1021/acsomega.1c06831] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 03/11/2022] [Indexed: 06/14/2023]
Abstract
We have investigated the possible connection between "dynamical anomaly" observed in time-resolved fluorescence measurements of reactive and nonreactive solute-centered relaxation dynamics in aqueous binary mixtures of different amphiphiles and the solution intra- and interspecies H-bond fluctuation dynamics. Earlier studies have connected the anomalous thermodynamic properties of binary mixtures at very low amphiphile concentrations to the structural distortion of water. This is termed as "structural anomaly." Interestingly, the abrupt changes in the composition-dependent average rates of solute relaxation dynamics occur at amphiphile mole fractions approximately twice as large as those where structural anomalies appear. We have investigated this anomalous solution dynamical aspect by considering (water + tertiary butanol) as a model system and performed molecular dynamics simulations at several tertiary butanol (TBA) concentrations covering the extremely dilute to the moderately concentrated regimes. The "dynamical anomaly" has been followed via monitoring the composition dependence of the intra- and interspecies H-bond fluctuations and reorientational relaxations of TBA and water molecules. Solution structural aspects have been followed via examining the tetrahedral order parameter, radial and spatial distribution functions, numbers of H bonds per water and TBA molecules, and the respective populations participating in H-bond formation. Our simulations reveal abrupt changes in the H-bond fluctuations and reorientational dynamics and tetrahedral order parameter at amphiphile concentrations differing approximately by a factor of 2 and corroborates well with the steady-state and the time-resolved spectroscopic measurements. This work therefore explains, following a uniform and cogent manner, both the experimentally observed structural and dynamical anomalies in microscopic terms.
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Perera A, Požar M, Lovrincevic B. Camel back shaped Kirkwood-Buff Integrals. J Chem Phys 2022; 156:124503. [DOI: 10.1063/5.0084520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Some binary mixtures, such as specific alcohol-alkane mixtures, or even water-tbutanol, exhibit two humps "camel back" shaped KBI. This is in sharp contrast with usual KBI of binary mixtures having a single extremum. This extremum is interpreted as the region of maximum concentration fluctuations, and usually occurs in binary mixtures presenting appreciable micro-segregation, and corresponds to where the mixture exhibit a percolation of the two species domains. In this paper, it is shown that two extrema occur in binary mixtures when one species forms "meta-particle" aggregates, the latter which act as a meta-species, and have their own concentration fluctuations, hence their own KBI extremum. This "meta-extremum" occurs at low concentration of the aggregate-forming species (such as alcohol in alkane), and is independant of the other usual extremum observed at mid volume fraction occupancy. These systems are a good illustration of the concept of the duality between concentration fluctuations and micro-segregation.
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Affiliation(s)
- Aurelien Perera
- Laboratoire de Physique Theorique de Matière Condensée, Sorbonne Université, France
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Kuchierskaya AA, Semenov AP, Sayfutdinova AR, Kopitsyn DS, Vinokurov VA, Anisimov MA, Novikov AA. Interfacial tension and phase properties of water – Hydrotrope – Oil solutions: Water – 2-butoxyethanol – Toluene. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.117683] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Jukić I, Požar M, Lovrinčević B, Perera A. Universal features in the lifetime distribution of clusters in hydrogen-bonding liquids. Phys Chem Chem Phys 2021; 23:19537-19546. [PMID: 34524299 DOI: 10.1039/d1cp02027g] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hydrogen-bonding liquids, typically water and alcohols, are known to form labile structures (network, chains, etc.); hence, the lifetime of these structures is an important microscopic parameter, which can be calculated via computer simulations. Since these cluster entities are mostly statistical in nature, one would expect that, in the short-timescale regime, their lifetime distribution would be a broad Gaussian-like function of time, with a single maximum representing their mean lifetime, and be weakly dependent on criteria such as the bonding distance and angle, much similar to non-hydrogen-bonding simple liquids, while the long-timescale regime is known to have some power law dependence. Unexpectedly, all the hydrogen-bonding liquids studied herein, namely water and alcohols, display three highly hierarchical specific lifetimes, in the sub-picosecond range 0-0.5 ps. The dominant lifetime depends very strongly on the bonding-distance criterion and is related to hydrogen-bonded pairs. This mode is absent in non-H-bonding simple liquids. The secondary and tertiary mean lifetimes are related to clusters and are nearly independent of the bonding criterion. Of these two lifetimes, only the first one can be related to that of simple liquids, which poses the question of the nature of the third lifetime. The study of alcohols reveals that this third lifetime is related to the topology of the H-bonded clusters and that its distribution may also be affected by the alkyl tail surrounding the "bath". This study shows that hydrogen-bonding liquids have a universal hierarchy of hydrogen-bonding lifetimes with a timescale regularity across very different types, and which depend on the topology of the cluster structures.
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Affiliation(s)
- Ivo Jukić
- Sorbonne Université, Laboratoire de Physique Théorique de la Matière Condensée (UMR CNRS 7600), 4 Place Jussieu, F75252, Paris cedex 05, France.
- University of Split, Faculty of Science, Ruđera Boškovića 33, 21000, Split, Croatia.
| | - Martina Požar
- University of Split, Faculty of Science, Ruđera Boškovića 33, 21000, Split, Croatia.
| | - Bernarda Lovrinčević
- University of Split, Faculty of Science, Ruđera Boškovića 33, 21000, Split, Croatia.
| | - Aurélien Perera
- Sorbonne Université, Laboratoire de Physique Théorique de la Matière Condensée (UMR CNRS 7600), 4 Place Jussieu, F75252, Paris cedex 05, France.
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Choi S, Parameswaran S, Choi JH. Effects of molecular shape on alcohol aggregation and water hydrogen bond network behavior in butanol isomer solutions. Phys Chem Chem Phys 2021; 23:12976-12987. [PMID: 34075966 DOI: 10.1039/d1cp00634g] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Despite butanol isomers such as n-butanol, sec-butanol, isobutanol and tert-butanol having the same chemical formula, their liquid-liquid phase diagrams are distinct. That is, tert-butanol is miscible in water at all concentrations, while the other three butanol isomers are partially miscible under ambient conditions. The molecular shape of tert-butanol is close to globular and differs from the other three butanol molecules with a relatively long carbon chain. By performing molecular dynamics simulations and graph theoretical analysis of the four water-butanol isomer mixtures at varying concentrations, we show how distinct butanol aggregates are formed which depend upon the molecular shape and affect the water H-bond network structure and phase diagram in the binary liquid. The three butanol isomers of n-butanol, sec-butanol and isobutanol at concentrated solutions form chain-like alcohol aggregates, but tert-butanol forms small aggregates due to the distinct packing behavior caused by its globular molecular shape. By employing the graph theoretical analysis such as the degree distribution and the eigenvalue spectrum from the adjacency matrix in the graphical representation of the alcohol H-bond network, we show that the tert-butanol aggregates have a different morphological structure from that of the other three butanol isomers in aqueous solution. The graph theoretically distinct butanol aggregates are categorized into two groups, water-compatible and water-incompatible, depending upon the interaction between the alcohol and water molecules. Based upon our observations, we propose that the water-incompatible networks of n-butanol, sec-butanol and isobutanol aggregates do not change the water structure significantly, forming two separate liquid phases that are alcohol-rich and water-rich. However, the water-compatible network of tert-butanol aggregates has a considerable interaction with the water molecules and causes significant disruption of the water H-bond network, forming a homogeneous solution. Understanding the alcohol aggregation behavior and water structure in butanol-water mixtures provides a critical clue in appreciating fundamental issues such as miscibility and phase separation in aqueous solution systems.
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Affiliation(s)
- Seungeui Choi
- Department of Chemistry, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea.
| | - Saravanan Parameswaran
- Department of Chemistry, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea.
| | - Jun-Ho Choi
- Department of Chemistry, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea.
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11
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Kokic Males V, Požar M. Why Should Metformin Not Be Given in Advanced Kidney Disease? Potential Leads from Computer Simulations. ACS OMEGA 2021; 6:15382-15391. [PMID: 34151116 PMCID: PMC8210427 DOI: 10.1021/acsomega.1c01744] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 05/14/2021] [Indexed: 06/13/2023]
Abstract
Metformin is considered as the go-to drug in the treatment of diabetes. However, it is either prescribed in lower doses or not prescribed at all to patients with kidney problems. To find a potential explanation for this practice, we employed atomistic-level computer simulations to simulate the transport of metformin through multidrug and toxin extrusion 1 (MATE1), a protein known to play a key role in the expulsion of metformin into urine. Herein, we examine the hydrogen bonding between MATE1 and one or more metformin molecules. The simulation results indicate that metformin continuously forms and breaks off hydrogen bonds with MATE1 residues. However, the mean hydrogen bond lifetimes increase for an order of magnitude when three metformin molecules are inserted instead of one. This new insight into the metformin transport process may provide the molecular foundation behind the clinical practice of not prescribing metformin to kidney disease patients.
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Affiliation(s)
- Visnja Kokic Males
- University Department
for Health Studies, University of Split, Ruđera Boškovića
35, 21000 Split, Croatia
| | - Martina Požar
- Faculty of Science, University of Split, Ruđera Boškovića 33, 21000 Split, Croatia
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12
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Cerar J, Jamnik A, Szilágyi I, Tomšič M. Solvation of nonionic poly(ethylene oxide) surfactant Brij 35 in organic and aqueous-organic solvents. J Colloid Interface Sci 2021; 594:150-159. [PMID: 33761392 DOI: 10.1016/j.jcis.2021.02.113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Revised: 02/23/2021] [Accepted: 02/24/2021] [Indexed: 11/17/2022]
Abstract
HYPOTHESIS By combining the experimental small- and wide-angle x-ray scattering (SWAXS) method with molecular dynamics simulations and the theoretical 'complemented-system approach' it is possible to obtain detailed information about the intra- and inter-molecular structure and dynamics of the solvation and hydration of the surfactant in organic and mixed solvents, e.g., of the nonionic surfactant Brij 35 (C12E23) in alcohols and aqueous alcohol-rich ternary systems. This first application of the complemented-system approach to the surfactant system will promote the use of this powerful methodology that is based on experimental and calculated SWAXS data in studies of colloidal systems. By applying high-performance computing systems, such an approach is readily available for studies in the colloidal domain. EXPERIMENTS SWAXS experiments and MD simulations were performed for binary Brij 35/alcohol and ternary Brij 35/water/alcohol systems with ethanol, n-butanol and n-hexanol as the organic solvent component at 25 °C. FINDINGS We confirmed the presence of solvated Brij 35 monomers in the studied organic media, revealed their preferential hydration and discussed their structural and dynamic features at the intra- and inter-molecular levels. Anisotropic effective surfactant molecular conformations were found. The influence of the hydrophobicity of the organic solvent on the hydration phenomena of surfactant molecules was explained.
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Affiliation(s)
- Jure Cerar
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia
| | - Andrej Jamnik
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia
| | - István Szilágyi
- MTA-SZTE Lendület Biocolloids Research Group, Interdisciplinary Excellence Center, Department of Physical Chemistry and Materials Science, University of Szeged, H-6720 Szeged, Hungary
| | - Matija Tomšič
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia.
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Jukić I, PoŽar M, Lovrinčević B. Comparative analysis of ethanol dynamics in aqueous and non-aqueous solutions. Phys Chem Chem Phys 2020; 22:23856-23868. [PMID: 33073281 DOI: 10.1039/d0cp03160g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
In this study, we compare the results for vibrational, reorientational and hydrogen bond dynamics of ethanol in water and in hexane across the whole concentration range. Water and hexane are both commonly used as solvents, but so far, it has been unclear to what extent they modify the solute dynamics. Ethanol is chosen as the solute because it is an aliphatic molecule that is miscibile with both solvents. It is known that ethanol forms micelle-like domains in water and cyclic clusters resembling loops in hexane. This structural micro-heterogeneity is well known both in experiments and in simulations. The main question we raise here is: is there a signature of micro-heterogeneity in the dynamical quantities of ethanol? We focus on quantities such as the vibrational spectra, the reorientational correlation functions, the self-diffusion coefficients, the ethanol-ethanol hydrogen bond correlation functions and the corresponding hydrogen bond histograms. For the first time ever, we compute the van Hove functions to reveal the dynamical variations of spatial correlations in these systems. All these results complement each other and provide a unifying dynamical description of ethanol in binary mixtures.
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Affiliation(s)
- Ivo Jukić
- Department of Physics, Faculty of Science, University of Split, Ruđera Boškovića 33, 21000 Split, Croatia.
| | - Martina PoŽar
- Department of Physics, Faculty of Science, University of Split, Ruđera Boškovića 33, 21000 Split, Croatia.
| | - Bernarda Lovrinčević
- Department of Physics, Faculty of Science, University of Split, Ruđera Boškovića 33, 21000 Split, Croatia.
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Pethes I, Pusztai L, Ohara K, Kohara S, Darpentigny J, Temleitner L. Temperature-dependent structure of methanol-water mixtures on cooling: X-ray and neutron diffraction and molecular dynamics simulations. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.113664] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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15
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Patil MR, Ganorkar SB, Patil AS, Shirkhedkar AA, Surana SJ. Hydrotropic Solubilization in Pharmaceutical Analysis: Origin, Evolution, Cumulative Trend and Precise Applications. Crit Rev Anal Chem 2020; 51:278-288. [DOI: 10.1080/10408347.2020.1718484] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Mangesh R. Patil
- Central Instruments Facility (CIF), Department of Pharmaceutical Chemistry, R. C. Patel Institute of Pharmaceutical Education and Research, Shirpur, Maharashtra, India
| | - Saurabh B. Ganorkar
- Central Instruments Facility (CIF), Department of Pharmaceutical Chemistry, R. C. Patel Institute of Pharmaceutical Education and Research, Shirpur, Maharashtra, India
| | - Amod S. Patil
- Central Instruments Facility (CIF), Department of Pharmaceutical Chemistry, R. C. Patel Institute of Pharmaceutical Education and Research, Shirpur, Maharashtra, India
| | - Atul A. Shirkhedkar
- Central Instruments Facility (CIF), Department of Pharmaceutical Chemistry, R. C. Patel Institute of Pharmaceutical Education and Research, Shirpur, Maharashtra, India
| | - Sanjay J. Surana
- Central Instruments Facility (CIF), Department of Pharmaceutical Chemistry, R. C. Patel Institute of Pharmaceutical Education and Research, Shirpur, Maharashtra, India
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Abstract
Based on the molecular dynamics method, the calculations for diffusion coefficients were carried out in binary aqueous solutions of three alcohols: ethanol, isopropanol, and tert-butanol. The intermolecular potential TIP4P/2005 was used for water; and five force fields were analyzed for the alcohols. The force fields providing the best accuracy of calculation were identified based on a comparison of the calculated self-diffusion coefficients of pure alcohols with the experimental data for internal (Einstein) diffusion coefficients of alcohols in solutions. The temperature and concentration dependences of the interdiffusion coefficients were determined using Darken’s Equation. Transport (Fickian) diffusion coefficients were calculated using a thermodynamic factor determined by the non-random two-liquid (NRTL) and Willson models. It was demonstrated that for adequate reproduction of the experimental data when calculating the transport diffusion coefficients, the thermodynamic factor has to be 0.64. Simple approximations were obtained, providing satisfactory accuracy in calculating the concentration and temperature dependences of the transport diffusion coefficients in the studied mixtures.
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