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Claude Treiner - One of the best experts on this subject based on the ideXlab platform.
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Coadsorption of naphthalene derivatives and cetyltrimethylammonium bromide on alumina/water, titanium dioxide/water and silica/water interfaces
Journal of Colloid and Interface Science, 1996Co-Authors: P. Favoriti, V. Monticone, Claude TreinerAbstract:The adsorption of cetyltrimethylamonium bromide at silica/water, alumina/water, and titanium dioxide/water interfaces has been determined at pH values for which these hydrophilic surfaces are all negatively charged. Then the coadsorption of 2(2-naphthyl) ethanol and 1-napthylamine onto the surfactant aggregates was investigated both below and above the critical micelle concentration (cmc). The solute uptake from the aqueous solution increases with surfactant surface coverage up to the cmc and decreases above the cmc as the result of free micelle formation and preferential Micellar Solubilization. Solute partition coefficients were determined both for the coadsorption and the Micellar Solubilization effects. Within experimental uncertainty, the coadsorption partition coefficient for each solute is independent of the solid substrate employed. It is solely a function of the surfactant adsorption and of the neutral solute properties. The coadsorption partition coefficient is equal to the Micellar Solubilization constant for the alcohol, but a ratio of about 2 in favor of the coadsorption constant is found for the amine. The possible origin of this effect is discussed.
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Micellar Solubilization thermodynamics of acetophenone in surfactant mixtures : case of benzyldimethyltetradecylammonium chloride and trimethyltetradecylammonium chloride
Colloid & Polymer Science, 1992Co-Authors: A. Makayssi, Claude TreinerAbstract:The thermodynamics of Micellar Solubilization of acetophenone in mixtures of two cationic surfactants [benzyldimethyltetradecylammonium chloride +trimethyltetradecylammonium chloride] has been derived from calorimetric measurements at controlled solute activity. The partition coefficient between micelles and water as well as the standard enthalpy and entropy of transfer between micelles and water were calculated. The results were compared to the case of benzylalcohol in the same cationic mixtures. For acetophenone, the variation of all thermodynamic transfer functions with Micellar composition may be described by the regular solution formalism. The same conclusion has been achieved for most polar solutes in various surfactant mixtures: favorable interaction between unlike surfactants induces an unfavorable Micellar Solubilization. Exceptions should be found with the cases where solute Solubilization induces profound Micellar changes. It seems to be the case with some alcohols in the cationic surfactant mixtures studied.
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Peculiar Solubilization thermodynamics of pentan-1-ol in mixed surfactant solutions of benzyldimethyltetradecylammonium chloride and trimethyltetradecylammonium chloride: a calorimetric investigation
Analytica Chimica Acta, 1991Co-Authors: Raymond Bury, Claude Treiner, Jean Chevalet, A. MakayssiAbstract:Abstract The thermodynamics of Micellar Solubilization were obtained from precise calorimetric measurements for pentan-1-ol in surfactant mixtures of benzyldimethyltetradecylammonium chloride (BzCl) and trimethyltetradecylammonium chloride (TACl) (system I). The partition coefficient P of pentan-1-ol between micelles and water passes through a maximum in the TACl-rich mixed micelles and through a minimum in the BzCl-rich micelles. This very unusual Solubilization behaviour is entropy controlled in the former Micellar composition and enthalpy controlled in the latter. The same behaviour is qualitatively displayed by benzyl alcohol in system I. In most aqueous binary surfactant solutions, Micellar Solubilization of polar solutes may be formally represented using the regular solution formalism but not in system I. A conductance study indicates that at surfactant concentrations two to five times above the critical micelle concentration, mixed micelles containing BzCl undergo structural changes that might be responsible for the peculiar Solubilization pattern observed.
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Extreme nonideal Micellar Solubilization behavior of benzyl alcohol in binary surfactant mixtures of benzyldimethyltetradecylammonium chloride and trimethyltetradecylammonium chloride
The Journal of Physical Chemistry, 1991Co-Authors: Raymond Bury, Embarek Souhalia, Claude TreinerAbstract:The thermodynamics of Micellar Solubilization of benzyl alcohol has been determined in mixtures of two cationic surfactants, trimethyltetradecylammonium chloride (I) and benzyldimethyltetradecylammonium chloride (II), using a calorimetric method. Although the cmc of mixtures of I and II display a behavior close to ideality, the partition coefficient P between mixed micelles and water present several extrema as a function of Micellar composition
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Peculiar Micellar Solubilization of benzyl alcohol in binary benzyldimethyletradecylammonium chloride and trimethyletradecylammonium chloride solutions: A calorimetric investigation
Trends in Colloid and Interface Science V, 1Co-Authors: Claude Treiner, Raymond BuryAbstract:The thermodynamics of Micellar Solubilization of benzyl alcohol in binary surfactant solutions of two cationic surfactants, benzyldimethyletradecylammonium chloride and trimethyletradecylammonium chloride (I) have been deduced from precise calorimetric measurements at controlled solute activity. Although the critical micelle concentration (CMC) of the surfactant mixtures display a nearly ideal behavior, the partition coefficient P between mixed micelles and water, as well as the standard enthalpy of transfer of benzyl alcohol between micelles and water present several extrema. These peculiar results are compared to those obtained previously for 1-pentanol in anionic + cationic (II) are anionic + nonionic (II) surfactant systems. It is shown that the regular solution formalism may be used to represent systems (II) and (III), assuming binary interactions between the surfactants, whereas for system I, ternary interactions between the surfactants are needed. A tentative moelcular interpretation of the data is proposed.
Raymond Bury - One of the best experts on this subject based on the ideXlab platform.
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Peculiar Solubilization thermodynamics of pentan-1-ol in mixed surfactant solutions of benzyldimethyltetradecylammonium chloride and trimethyltetradecylammonium chloride: a calorimetric investigation
Analytica Chimica Acta, 1991Co-Authors: Raymond Bury, Claude Treiner, Jean Chevalet, A. MakayssiAbstract:Abstract The thermodynamics of Micellar Solubilization were obtained from precise calorimetric measurements for pentan-1-ol in surfactant mixtures of benzyldimethyltetradecylammonium chloride (BzCl) and trimethyltetradecylammonium chloride (TACl) (system I). The partition coefficient P of pentan-1-ol between micelles and water passes through a maximum in the TACl-rich mixed micelles and through a minimum in the BzCl-rich micelles. This very unusual Solubilization behaviour is entropy controlled in the former Micellar composition and enthalpy controlled in the latter. The same behaviour is qualitatively displayed by benzyl alcohol in system I. In most aqueous binary surfactant solutions, Micellar Solubilization of polar solutes may be formally represented using the regular solution formalism but not in system I. A conductance study indicates that at surfactant concentrations two to five times above the critical micelle concentration, mixed micelles containing BzCl undergo structural changes that might be responsible for the peculiar Solubilization pattern observed.
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Extreme nonideal Micellar Solubilization behavior of benzyl alcohol in binary surfactant mixtures of benzyldimethyltetradecylammonium chloride and trimethyltetradecylammonium chloride
The Journal of Physical Chemistry, 1991Co-Authors: Raymond Bury, Embarek Souhalia, Claude TreinerAbstract:The thermodynamics of Micellar Solubilization of benzyl alcohol has been determined in mixtures of two cationic surfactants, trimethyltetradecylammonium chloride (I) and benzyldimethyltetradecylammonium chloride (II), using a calorimetric method. Although the cmc of mixtures of I and II display a behavior close to ideality, the partition coefficient P between mixed micelles and water present several extrema as a function of Micellar composition
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Peculiar Micellar Solubilization of benzyl alcohol in binary benzyldimethyletradecylammonium chloride and trimethyletradecylammonium chloride solutions: A calorimetric investigation
Trends in Colloid and Interface Science V, 1Co-Authors: Claude Treiner, Raymond BuryAbstract:The thermodynamics of Micellar Solubilization of benzyl alcohol in binary surfactant solutions of two cationic surfactants, benzyldimethyletradecylammonium chloride and trimethyletradecylammonium chloride (I) have been deduced from precise calorimetric measurements at controlled solute activity. Although the critical micelle concentration (CMC) of the surfactant mixtures display a nearly ideal behavior, the partition coefficient P between mixed micelles and water, as well as the standard enthalpy of transfer of benzyl alcohol between micelles and water present several extrema. These peculiar results are compared to those obtained previously for 1-pentanol in anionic + cationic (II) are anionic + nonionic (II) surfactant systems. It is shown that the regular solution formalism may be used to represent systems (II) and (III), assuming binary interactions between the surfactants, whereas for system I, ternary interactions between the surfactants are needed. A tentative moelcular interpretation of the data is proposed.
Naír Rodríguez-hornedo - One of the best experts on this subject based on the ideXlab platform.
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Mechanistic Analysis of Cocrystal Dissolution as a Function of pH and Micellar Solubilization.
Molecular pharmaceutics, 2016Co-Authors: Fengjuan Cao, Naír Rodríguez-hornedo, Gordon L Amidon, Gregory E AmidonAbstract:The purpose of this work is to provide a mechanistic understanding of the dissolution behavior of cocrystals under the influence of ionization and Micellar Solubilization. Mass transport models were developed by applying Fick’s law of diffusion to dissolution with simultaneous chemical reactions in the hydrodynamic boundary layer adjacent to the dissolving cocrystal surface to predict the pH at the dissolving solid–liquid interface (i.e., interfacial pH) and the flux of cocrystals. To evaluate the predictive power of these models, dissolution studies of carbamazepine–saccharin (CBZ-SAC) and carbamazepine–salicylic acid (CBZ-SLC) cocrystals were performed at varied pH and surfactant concentrations above the critical stabilization concentration (CSC), where the cocrystals were thermodynamically stable. The findings in this work demonstrate that the pH dependent dissolution behavior of cocrystals with ionizable components is dependent on interfacial pH. This mass transport analysis demonstrates the importanc...
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Engineering cocrystal solubility, stability, and pHmax by Micellar Solubilization
Journal of pharmaceutical sciences, 2011Co-Authors: Neal Huang, Naír Rodríguez-hornedoAbstract:Cocrystals offer great promise in enhancing drug aqueous solubilities, but face the challenge of conversion to a less soluble drug when in contact with solvent. This manuscript shows that differential Solubilization of cocrystal components by micelles can impart thermo- dynamic stability to otherwise unstable cocrystals. The theoretical foundation for controlling cocrystal solubility and stability is presented by considering the contributions of Micellar solubi- lization and ionization of cocrystal components. A surfactant critical stabilization concentration (CSC) and a solution pH (pHmax) where cocrystal and drug are thermodynamically stable are shown to characterize cocrystal stability in Micellar solutions. The solubility, CSC, and pHmax of carbamazepine cocrystals in Micellar solutions of sodium lauryl sulfate predicted by the models are in very good agreement with experimental measurements. The findings from this work demonstrate that cocrystal CSC and pHmax can be tailored from the selection of coformer and solubilizing additives such as surfactants, thus providing an unprecedented level of control over cocrystal stability and solubility via solution phase chemistry. © 2011 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 100:5219-5234, 2011
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Engineering cocrystal thermodynamic stability and eutectic points by Micellar Solubilization and ionization
CrystEngComm, 2011Co-Authors: Neal Huang, Naír Rodríguez-hornedoAbstract:Pharmaceutical cocrystals are of great interest because of their potential to enhance solubility and bioavailability of poorly water-soluble drugs. Cocrystal development is however limited by their poor thermodynamic stability in aqueous environments. The work presented here describes the mechanisms by which cocrystal stability can be fine-tuned via Micellar Solubilization and ionization of cocrystal components. An important feature of cocrystal solution equilibria is the existence of eutectic points involving coexistence of three phases, a liquid and two solids. The solution composition at the eutectic points is a critical parameter that defines the conditions of thermodynamic stability. Equations that describe the sensitivity of eutectic points and phase diagrams to Micellar surfactants and pH are presented. Predictions are in excellent agreement with the behavior of several carbamazepine cocrystals in aqueous solutions of sodium lauryl sulfate. Increasing the magnitude of Micellar Solubilization for one of the cocrystal components is found to confer greater thermodynamic stability to the cocrystal and expand its stability region. These findings provide an unprecedented level of control over cocrystal-solution phase behavior, and are applicable to multiple additives and Solubilization mechanisms that may be required for the stabilization of highly soluble cocrystals.
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Effect of Micellar Solubilization on Cocrystal Solubility and Stability
Crystal Growth & Design, 2010Co-Authors: Neal Huang, Naír Rodríguez-hornedoAbstract:Micellar Solubilization of cocrystals is explained by the distribution of cocrystal components in Micellar and aqueous pseudophases. The dependence of cocrystal Solubilization on surfactant concentration is characterized by nonlinear behavior and an intersection of the solubility curves of cocrystal (RHA) and constituent (R) solid phases at the CSC, critical stabilization concentration. The effectiveness of a surfactant to stabilize cocrystals is related to the differential Solubilization of cocrystal components (Ks).
Santanu Paria - One of the best experts on this subject based on the ideXlab platform.
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surfactant enhanced remediation of organic contaminated soil and water
Advances in Colloid and Interface Science, 2008Co-Authors: Santanu PariaAbstract:Surfactant based remediation technologies for organic contaminated soil and water (groundwater or surface water) is of increasing importance recently. Surfactants are used to dramatically expedite the process, which in turn, may reduce the treatment time of a site compared to use of water alone. In fact, among the various available remediation technologies for organic contaminated sites, surfactant based process is one of the most innovative technologies. To enhance the application of surfactant based technologies for remediation of organic contaminated sites, it is very important to have a better understanding of the mechanisms involved in this process. This paper will provide an overview of the recent developments in the area of surfactant enhanced soil and groundwater remediation processes, focusing on (i) surfactant adsorption on soil, (ii) Micellar Solubilization of organic hydrocarbons, (iii) superSolubilization, (iv) density modified displacement, (v) degradation of organic hydrocarbon in presence surfactants, (vi) partitioning of surfactants onto soil and liquid organic phase, (vii) partitioning of contaminants onto soil, and (viii) removal of organics from soil in presence of surfactants. Surfactant adsorption on soil and/or sediment is an important step in this process as it results in surfactant loss reduced the availability of the surfactants for Solubilization. At the same time, adsorbed surfactants will retained in the soil matrix, and may create other environmental problem. The biosurfactants are become promising in this application due to their environmentally friendly nature, nontoxic, low adsorption on to soil, and good Solubilization efficiency. Effects of different parameters like the effect of electrolyte, pH, soil mineral and organic content, soil composition etc. on surfactant adsorption are discussed here. Micellar Solubilization is also an important step for removal of organic contaminants from the soil matrix, especially for low aqueous solubility organic contaminants. Influences of different parameters such as single and mixed surfactant system, hydrophilic and hydrophobic chain length, HLB value, temperature, electrolyte, surfactant type that are very important in Micellar Solubilization are reviewed here. Microemulsion systems show higher capacity of organic hydrocarbons Solubilization than the normal Micellar system. In the case of biodegradation of organic hydrocarbons, the rate is very slow due to low water solubility and dissolution rate but the presence of surfactants may increase the bioavailability of hydrophobic compounds by Solubilization and hence increases the degradation rate. In some cases the presence of it also reduces the rate. In addition to fundamental studies, some laboratory and field studies on removal of organics from contaminated soil are also reviewed to show the applicability of this technology.
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surfactant enhanced remediation of organic contaminated soil and water
Advances in Colloid and Interface Science, 2008Co-Authors: Santanu PariaAbstract:Surfactant based remediation technologies for organic contaminated soil and water (groundwater or surface water) is of increasing importance recently. Surfactants are used to dramatically expedite the process, which in turn, may reduce the treatment time of a site compared to use of water alone. In fact, among the various available remediation technologies for organic contaminated sites, surfactant based process is one of the most innovative technologies. To enhance the application of surfactant based technologies for remediation of organic contaminated sites, it is very important to have a better understanding of the mechanisms involved in this process. This paper will provide an overview of the recent developments in the area of surfactant enhanced soil and groundwater remediation processes, focusing on (i) surfactant adsorption on soil, (ii) Micellar Solubilization of organic hydrocarbons, (iii) superSolubilization, (iv) density modified displacement, (v) degradation of organic hydrocarbon in presence surfactants, (vi) partitioning of surfactants onto soil and liquid organic phase, (vii) partitioning of contaminants onto soil, and (viii) removal of organics from soil in presence of surfactants. Surfactant adsorption on soil and/or sediment is an important step in this process as it results in surfactant loss reduced the availability of the surfactants for Solubilization. At the same time, adsorbed surfactants will retained in the soil matrix, and may create other environmental problem. The biosurfactants are become promising in this application due to their environmentally friendly nature, nontoxic, low adsorption on to soil, and good Solubilization efficiency. Effects of different parameters like the effect of electrolyte, pH, soil mineral and organic content, soil composition etc. on surfactant adsorption are discussed here. Micellar Solubilization is also an important step for removal of organic contaminants from the soil matrix, especially for low aqueous solubility organic contaminants. Influences of different parameters such as single and mixed surfactant system, hydrophilic and hydrophobic chain length, HLB value, temperature, electrolyte, surfactant type that are very important in Micellar Solubilization are reviewed here. Microemulsion systems show higher capacity of organic hydrocarbons Solubilization than the normal Micellar system. In the case of biodegradation of organic hydrocarbons, the rate is very slow due to low water solubility and dissolution rate but the presence of surfactants may increase the bioavailability of hydrophobic compounds by Solubilization and hence increases the degradation rate. In some cases the presence of it also reduces the rate. In addition to fundamental studies, some laboratory and field studies on removal of organics from contaminated soil are also reviewed to show the applicability of this technology.
A. Makayssi - One of the best experts on this subject based on the ideXlab platform.
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Micellar Solubilization thermodynamics of acetophenone in surfactant mixtures : case of benzyldimethyltetradecylammonium chloride and trimethyltetradecylammonium chloride
Colloid & Polymer Science, 1992Co-Authors: A. Makayssi, Claude TreinerAbstract:The thermodynamics of Micellar Solubilization of acetophenone in mixtures of two cationic surfactants [benzyldimethyltetradecylammonium chloride +trimethyltetradecylammonium chloride] has been derived from calorimetric measurements at controlled solute activity. The partition coefficient between micelles and water as well as the standard enthalpy and entropy of transfer between micelles and water were calculated. The results were compared to the case of benzylalcohol in the same cationic mixtures. For acetophenone, the variation of all thermodynamic transfer functions with Micellar composition may be described by the regular solution formalism. The same conclusion has been achieved for most polar solutes in various surfactant mixtures: favorable interaction between unlike surfactants induces an unfavorable Micellar Solubilization. Exceptions should be found with the cases where solute Solubilization induces profound Micellar changes. It seems to be the case with some alcohols in the cationic surfactant mixtures studied.
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Peculiar Solubilization thermodynamics of pentan-1-ol in mixed surfactant solutions of benzyldimethyltetradecylammonium chloride and trimethyltetradecylammonium chloride: a calorimetric investigation
Analytica Chimica Acta, 1991Co-Authors: Raymond Bury, Claude Treiner, Jean Chevalet, A. MakayssiAbstract:Abstract The thermodynamics of Micellar Solubilization were obtained from precise calorimetric measurements for pentan-1-ol in surfactant mixtures of benzyldimethyltetradecylammonium chloride (BzCl) and trimethyltetradecylammonium chloride (TACl) (system I). The partition coefficient P of pentan-1-ol between micelles and water passes through a maximum in the TACl-rich mixed micelles and through a minimum in the BzCl-rich micelles. This very unusual Solubilization behaviour is entropy controlled in the former Micellar composition and enthalpy controlled in the latter. The same behaviour is qualitatively displayed by benzyl alcohol in system I. In most aqueous binary surfactant solutions, Micellar Solubilization of polar solutes may be formally represented using the regular solution formalism but not in system I. A conductance study indicates that at surfactant concentrations two to five times above the critical micelle concentration, mixed micelles containing BzCl undergo structural changes that might be responsible for the peculiar Solubilization pattern observed.