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Tchakalova V, Oliveira CLP, Figueiredo Neto AM. New Lyotropic Complex Fluid Structured in Sheets of Ellipsoidal Micelles Solubilizing Fragrance Oils. ACS OMEGA 2023; 8:29568-29584. [PMID: 37599987 PMCID: PMC10433498 DOI: 10.1021/acsomega.3c03500] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 07/14/2023] [Indexed: 08/22/2023]
Abstract
New lyotropic, fragranced, viscoelastic fluid with a complex structure is obtained from fragranced microemulsions by the addition of a fatty acid. Nonhomogeneous mixing of an appropriate nonionic surfactant, a fatty acid, and a fragrance oil led to the formation of anisotropically shaped and highly oriented micelles in aqueous solution. The nano- and microstructures, and consequently the viscosity, are controlled by the balance of fatty acids used as a cosurfactant and fragrance molecules, which partly behave as a cosurfactant and partly segregate in the micelles of the hydrophilic nonionic surfactant. The transition from isotropic microemulsion to a more structured viscoelastic solution is characterized by X-ray scattering and rheological methods. Considering our X-ray scattering results, we propose a structure composed of planar sheets of ellipsoidal micelles arranged in a lamellar type of stacking. The complex structured, low viscous, transparent fluid is capable of solubilizing a fragrance inside the ellipsoidal micelles, as well as retaining microparticles containing fragrance, without the addition of a polymeric thickener or another gelator. These features allow the creation of a 2-in-1 fragrance-solubilizing liquid product compatible with all types of home and body care consumer products.
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Affiliation(s)
- Vera Tchakalova
- Materials Science Department, R&D Division, Firmenich SA, 7 Rue de la Bergère, 1242 Satigny, Switzerland
| | - Cristiano Luis Pinto Oliveira
- Complex Fluids Group, Institute of Physics, University of São Paulo, Rua do Matão, 1371, Butantã, São Paulo-SP-Brazil CEP 05508-090, Brazil
| | - Antonio Martins Figueiredo Neto
- Complex Fluids Group, Institute of Physics, University of São Paulo, Rua do Matão, 1371, Butantã, São Paulo-SP-Brazil CEP 05508-090, Brazil
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2
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Pereira JC, Valente AJ, Söderman O. α-Cyclodextrin affects the acid-base properties of octanoic acid/sodium octanoate. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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3
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Mella M, Tagliabue A. Impact of Chemically Specific Interactions between Anions and Weak Polyacids on Chain Ionization, Conformations, and Solution Energetics. Macromolecules 2022. [DOI: 10.1021/acs.macromol.1c02625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Massimo Mella
- Dipartimento di Scienza ed Alta Tecnologia, Università degli Studi dell’Insubria, via Valleggio 11, 22100 Como (I), Italy
| | - Andrea Tagliabue
- Dipartimento di Scienza ed Alta Tecnologia, Università degli Studi dell’Insubria, via Valleggio 11, 22100 Como (I), Italy
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4
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Jamadagni SN, Ko X, Thomas JB, Eike DM. Salt- and pH-Dependent Viscosity of SDS/LAPB Solutions: Experiments and a Semiempirical Thermodynamic Model. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:8714-8725. [PMID: 34270265 DOI: 10.1021/acs.langmuir.1c00964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
We present novel data on the composition-, pH-, and salt-dependent zero shear viscosity of the commercially important mixture of anionic sodium dodecyl sulfate (SDS) and zwitterionic lauramidopropyl betaine (LAPB). We show via proton NMR experiments that the notionally zwitterionic LAPB exhibits a large pKa shift in the presence of SDS and can become partially cationic at formulation-relevant pH ranges of 4.5-6.0-that is, the binary system is effectively a ternary system. This has a pronounced effect on the viscosity of the system at low pH, especially if the fraction of LAPB is high. We use theoretical arguments to motivate a semiempirical but practical approach to model the viscosity of the mixtures using thermodynamic parameters such as the excess chemical potentials or activity coefficients of the surfactants. We demonstrate this using an augmented regular solution theory-based mixed micelle thermodynamic model and develop robust regression models using Bayesian approaches. We also show how the pKa shift from NMR experiments can be used to parameterize the thermodynamic model. This framework should be extensible to other arbitrary surfactant mixtures in the future and hence will be of broad interest for the development of surfactant formulations for household, personal care, and other applications.
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Affiliation(s)
- Sumanth N Jamadagni
- The Procter & Gamble Company, 8700 Mason Montgomery Road, Mason, Ohio 45040, United States
| | - Xueying Ko
- Department of Chemical and Biomolecular Engineering, Ohio University, Athens, Ohio 45701, United States
| | - Jacqueline B Thomas
- The Procter & Gamble Company, 8700 Mason Montgomery Road, Mason, Ohio 45040, United States
| | - David M Eike
- The Procter & Gamble Company, 8700 Mason Montgomery Road, Mason, Ohio 45040, United States
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5
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Mella M, Tagliabue A, Vaghi S, Izzo L. Evidences for charged hydrogen bonds on surfaces bearing weakly basic pendants: The case of PMMA–ran–PDMAEMA polymeric films. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2021.126525] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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6
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Mella M, Tagliabue A, Izzo L. On the distribution of hydrophilic polyelectrolytes and their counterions around zwitterionic micelles: the possible impact on the charge density in solution. SOFT MATTER 2021; 17:1267-1283. [PMID: 33300543 DOI: 10.1039/d0sm01541e] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Despite their charge neutrality, micelles composed of surfactants with zwitterionic headgroups selectively accumulate anions at their hydrophobic core/solution interphase due to electrostatic interactions if headgroup positive moieties are the innermost. This tendency may be markedly enhanced if polyions substitute simple ions. To investigate this possibility, solutions composed of zwitterionic micelles and hydrophilic polyanions have been investigated with Monte Carlo simulations representing the studied systems via primitive electrolyte models. Structural and energetic properties are obtained to highlight the impact of connecting simple ions into polyions on the interactions between electrolytes and micelles. Despite the latter, polyanions conserve their conformational properties. A marked increase in the concentration of charged species inside the micellar corona is, instead, found when polyions are present independently of their charge sign or the headgroup structure. Thus, polyelectrolytes act as "shuttle" for all charged species, with the potential of increasing reactions rates involving the latter due to mass effects. Besides, results for the polyions/micelles mixing free energy and Helmholtz energy profiles indicate that the critical micelle concentration is impacted minimally by hydrophilic polyelectrolytes, an outcome agreeing with experiments. This finding is entirely due to weak enthalpic effects while mixing hydrophilic polyions and micelles. A strong reduction in the screening of the micelle negative charge, acquired following the adsorption of anions in the corona and due to counterions layering just outside it (the so called "chameleon effect"), is forecasted when polyanions substitute monovalent anions.
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Affiliation(s)
- Massimo Mella
- Dipartimento di Scienza ed Alta Tecnologia, Università degli Studi dell'Insubria, via Valleggio 11, 22100, Como, Italy.
| | - Andrea Tagliabue
- Dipartimento di Scienza ed Alta Tecnologia, Università degli Studi dell'Insubria, via Valleggio 11, 22100, Como, Italy.
| | - Lorella Izzo
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell'Insubria, via J. H. Dunant 3, 21100, Varese, Italy
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7
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Sawada D, Hirono A, Asakura K, Banno T. pH-Tolerant giant vesicles composed of cationic lipids with imine linkages and oleic acids. RSC Adv 2020; 10:34247-34253. [PMID: 35519057 PMCID: PMC9056790 DOI: 10.1039/d0ra06822e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 09/08/2020] [Indexed: 02/05/2023] Open
Abstract
Giant vesicles (GVs) have attracted attention as functional materials because they can encapsulate both hydrophilic and hydrophobic compounds. For next generation functional GVs, both tolerance and stimuli-sensitivity are needed. So far, vesicles tolerant to acidic or basic conditions were generated using a mixture of cationic lipids and fatty acids. Here, to create functional GVs that are tolerant to a wide pH range but sensitively respond at below a specific pH, the behaviour of GVs composed of a cationic lipid with an imine bond and oleic acid was investigated. Even though the GVs prepared by the film swelling method were tolerant to strongly acidic conditions, GVs without oleic acid gradually shrank, accompanied by the generation of oil droplets at the same pH. 1H NMR analysis revealed that during hydration of the film, the imine bond hydrolysed to provide a cationic surfactant and an oil component in the presence of oleic acid due to its own Lewis basicity, suggesting the dissociation of oleic acid. The results of fluorescence spectroscopy using an environment-responsive probe and IR spectroscopy indicated that the GV tolerance originated from the intermolecular interactions of cationic lipids and anionic oleate. Giant vesicles composed of cationic lipids having an imine linkage and oleic acid were stable at strong acidic conditions.![]()
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Affiliation(s)
- Daichi Sawada
- Department of Applied Chemistry
- Faculty of Science and Technology
- Keio University
- Yokohama 223-8522
- Japan
| | - Ayana Hirono
- Department of Applied Chemistry
- Faculty of Science and Technology
- Keio University
- Yokohama 223-8522
- Japan
| | - Kouichi Asakura
- Department of Applied Chemistry
- Faculty of Science and Technology
- Keio University
- Yokohama 223-8522
- Japan
| | - Taisuke Banno
- Department of Applied Chemistry
- Faculty of Science and Technology
- Keio University
- Yokohama 223-8522
- Japan
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Travaglini L, di Gregorio MC, Severoni E, D'Annibale A, Sennato S, Tardani F, Giustini M, Gubitosi M, Del Giudice A, Galantini L. Deoxycholic acid and l-Phenylalanine enrich their hydrogel properties when combined in a zwitterionic derivative. J Colloid Interface Sci 2019; 554:453-462. [PMID: 31325679 DOI: 10.1016/j.jcis.2019.07.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 07/05/2019] [Accepted: 07/07/2019] [Indexed: 01/31/2023]
Abstract
HYPOTHESIS Sodium Deoxycholate (NaDC) and Phenylalanine (Phe) are important biological hydrogelators. NaDC hydrogels form by lowering the pH or by increasing the ionic strength. Phe gels form from saturated solution by thermal induction and slow kinetics. The resulting gels hold great potential in medicine and biology as drug carriers and models for fundamental self-assembly in pathological conditions. Based on this background it was hypothesized that a Phe substituted NaDC could provide a molecule with expanded gelling ability, merging those of the precursors. EXPERIMENTS We coupled both building blocks in a zwitterionic derivative bearing a Phe residue at the C3 carbon of NaDC. The specific zwitterionic structure, the concurrent use of Ca2+ ions for the carboxyl group coordination and the pH control generate conditions for the formation of hydrogels. The hydrogels were analyzed by combining UV and circular dichroism spectroscopies, rheology, small angle X-ray scattering and atomic force microscopy. FINDINGS Hydrogel appearance occurs in conditions that are uncovered in the case of the pure Phe and NaDC: self-standing gels form instantaneously at room temperature, in the 10-12 pH range and down to concentration of 0.17 wt%. Both thixotropic and shake resistant gels can form depending on the derivative concentration. The gels show an uncommon thermal stability in the scanned range of 20-60 °C. The reported system concurrently enriches the hydrogelation properties of two relevant building blocks. We anticipate some potential applications of such gels in materials science where coordination of metal ions can be exploited for templating inorganic nanostructures.
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Affiliation(s)
- Leana Travaglini
- Department of Chemistry, Sapienza University of Rome, P. le A. Moro 5, 00185 Rome, Italy
| | | | - Emilia Severoni
- Department of Chemistry, Sapienza University of Rome, P. le A. Moro 5, 00185 Rome, Italy
| | - Andrea D'Annibale
- Department of Chemistry, Sapienza University of Rome, P. le A. Moro 5, 00185 Rome, Italy
| | - Simona Sennato
- CNR-ISC UOS Sapienza, Sapienza University of Rome, P. le A. Moro 5, 00185 Roma, Italy; Department of Physics, Sapienza University of Rome, P. le A. Moro 5, 00185 Roma, Italy
| | - Franco Tardani
- CNR-ISC UOS Sapienza, Sapienza University of Rome, P. le A. Moro 5, 00185 Roma, Italy
| | - Mauro Giustini
- Department of Chemistry, Sapienza University of Rome, P. le A. Moro 5, 00185 Rome, Italy
| | - Marta Gubitosi
- Department of Chemistry, Sapienza University of Rome, P. le A. Moro 5, 00185 Rome, Italy
| | - Alessandra Del Giudice
- Department of Chemistry, Sapienza University of Rome, P. le A. Moro 5, 00185 Rome, Italy
| | - Luciano Galantini
- Department of Chemistry, Sapienza University of Rome, P. le A. Moro 5, 00185 Rome, Italy.
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9
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Barroso daSilva FL, Dias LG. Development of constant-pH simulation methods in implicit solvent and applications in biomolecular systems. Biophys Rev 2017; 9:699-728. [PMID: 28921104 PMCID: PMC5662048 DOI: 10.1007/s12551-017-0311-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 08/01/2017] [Indexed: 12/20/2022] Open
Abstract
pH is a critical parameter for biological and technological systems directly related with electrical charges. It can give rise to peculiar electrostatic phenomena, which also makes them more challenging. Due to the quantum nature of the process, involving the forming and breaking of chemical bonds, quantum methods should ideally by employed. Nevertheless, due to the very large number of ionizable sites, different macromolecular conformations, salt conditions, and all other charged species, the CPU time cost simply becomes prohibitive for computer simulations, making this a quite complex problem. Simplified methods based on Monte Carlo sampling have been devised and will be reviewed here, highlighting the updated state-of-the-art of this field, advantages, and limitations of different theoretical protocols for biomolecular systems (proteins and nucleic acids). Following a historical perspective, the discussion will be associated with the applications to protein interactions with other proteins, polyelectrolytes, and nanoparticles.
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Affiliation(s)
- Fernando Luís Barroso daSilva
- Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Av. do café, s/no. - Universidade de São Paulo, BR-14040-903, Ribeirão Preto, SP, Brazil.
- UCD School of Physics, UCD Institute for Discovery, University College Dublin, Belfield, Dublin 4, Ireland.
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA.
| | - Luis Gustavo Dias
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Av. Bandeirantes, 3900 - Universidade de São Paulo, BR-14040-901, Ribeirão Preto, SP, Brazil
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10
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Mella M, Izzo L. Modulation of ionization and structural properties of weak polyelectrolytes due to 1D, 2D, and 3D confinement. ACTA ACUST UNITED AC 2017. [DOI: 10.1002/polb.24351] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Massimo Mella
- Dipartimento di Scienza ed Alta Tecnologia; Università degli Studi dell'Insubria; via Valleggio 9 Como 22100 Italy
| | - Lorella Izzo
- Dipartimento di Chimica e Biologia; Università degli Studi di Salerno; via Giovanni Paolo II, 132 Fisciano 84084 Italy
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11
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Wolfrum S, Marcus J, Touraud D, Kunz W. A renaissance of soaps? - How to make clear and stable solutions at neutral pH and room temperature. Adv Colloid Interface Sci 2016; 236:28-42. [PMID: 27476328 DOI: 10.1016/j.cis.2016.07.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 07/14/2016] [Accepted: 07/14/2016] [Indexed: 01/06/2023]
Abstract
Soaps are the oldest and perhaps most natural surfactants. However, they lost much of their importance since "technical surfactants", usually based on sulfates or sulfonates, have been developed over the last fifty years. Indeed, soaps are pH- and salt-sensitive and they are irritant, especially to the eyes. In food emulsions, although authorized, they have a bad taste, and long-chain saturated soaps have a high Krafft temperature. We believe that most or perhaps all of these problems can be solved with modern formulation approaches. We start this paper with a short overview of our present knowledge of soaps and soap formulations. Then we focus on the problem of the lacking soap solubility at neutral pH values. For example, it is well known that with the food emulsifier sodium oleate (NaOl), clear and stable aqueous solutions can only be obtained at pH values higher than 10. A decrease in the pH value leads to turbid and unstable solutions. This effect is not compatible with the formulation of aqueous stable and drinkable formulations with neutral or even acidic pH values. However, the pH value/phase behavior of aqueous soap solutions can be altered by the addition of other surfactants. Such a surfactant can be Rebaudioside A (RebA), a steviol glycoside from the plant Stevia rebaudiana which is used as a natural food sweetener. In a recent paper, we showed the influence of RebA on the apKa value of sodium oleate in a beverage microemulsion and on its clearing temperature. In the present paper, we report on the effect of the edible bio-surfactant RebA, on the macroscopic and microscopic phase behavior of simple aqueous sodium oleate solutions at varying pH values. The macroscopic phase behavior is investigated by visual observation and turbidity measurements. The microscopic phase behavior is analyzed by acid-base titration curves, phase-contrast and electron microscopy. It turned out that even at neutral pH, aqueous NaOl/RebA solutions can be completely clear and stable for more than 50days at room temperature. This is for the first time that a long chain soap could be really solubilized in water at neutral pH at room temperature. At last, these findings were applied to prepare stable, highly translucent and drinkable aqueous solutions of omega-3-fatty acids at a pH value of 7.5.
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12
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Dey N, Bhattacharya S. A Glimpse of Our Journey into the Design of Optical Probes in Self-assembled Surfactant Aggregates. CHEM REC 2016; 16:1934-49. [DOI: 10.1002/tcr.201600012] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Indexed: 02/05/2023]
Affiliation(s)
- Nilanjan Dey
- Department of Organic Chemistry; Indian Institute of Science; Bangalore 560012 India
| | - Santanu Bhattacharya
- Department of Organic Chemistry; Indian Institute of Science; Bangalore 560012 India
- Indian Association for the Cultivation of Science; 2A and 2B Raja S. C. Mullick Road Jadavpur Kolkata 700032 India
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13
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Solntsev KM, Popov AV, Solovyeva VA, Al-Ainain SA, Il’ichev YV, Hernandez R, Kuzmin MG. Kinetics of intra- and intermolecular excited-state proton transfer ofω-(2-hydroxynaphthyl-1)-decanoic acid in homogeneous and micellar solutions. Methods Appl Fluoresc 2015. [DOI: 10.1088/2050-6120/4/1/014001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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14
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Marcus J, Wolfrum S, Touraud D, Kunz W. Influence of high intensity sweeteners and sugar alcohols on a beverage microemulsion. J Colloid Interface Sci 2015; 460:105-12. [DOI: 10.1016/j.jcis.2015.08.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 08/19/2015] [Accepted: 08/20/2015] [Indexed: 11/25/2022]
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15
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Morrow BH, Eike DM, Murch BP, Koenig PH, Shen JK. Predicting proton titration in cationic micelle and bilayer environments. J Chem Phys 2015; 141:084714. [PMID: 25173037 DOI: 10.1063/1.4893439] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Knowledge of the protonation behavior of pH-sensitive molecules in micelles and bilayers has significant implications in consumer product development and biomedical applications. However, the calculation of pKa's in such environments proves challenging using traditional structure-based calculations. Here we apply all-atom constant pH molecular dynamics with explicit ions and titratable water to calculate the pKa of a fatty acid molecule in a micelle of dodecyl trimethylammonium chloride and liquid as well as gel-phase bilayers of diethyl ester dimethylammonium chloride. Interestingly, the pKa of the fatty acid in the gel bilayer is 5.4, 0.4 units lower than that in the analogous liquid bilayer or micelle, despite the fact that the protonated carboxylic group is significantly more desolvated in the gel bilayer. This work illustrates the capability of all-atom constant pH molecular dynamics in capturing the delicate balance in the free energies of desolvation and Coulombic interactions. It also shows the importance of the explicit treatment of ions in sampling the protonation states. The ability to model dynamics of pH-responsive substrates in a bilayer environment is useful for improving fabric care products as well as our understanding of the side effects of anti-inflammatory drugs.
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Affiliation(s)
- Brian H Morrow
- Department of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland 21201, USA
| | - David M Eike
- Computational Chemistry, Modeling and Simulation GCO, Procter and Gamble, Cincinnati, Ohio 45201, USA
| | - Bruce P Murch
- Computational Chemistry, Modeling and Simulation GCO, Procter and Gamble, Cincinnati, Ohio 45201, USA
| | - Peter H Koenig
- Computational Chemistry, Modeling and Simulation GCO, Procter and Gamble, Cincinnati, Ohio 45201, USA
| | - Jana K Shen
- Department of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland 21201, USA
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16
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Doshi N, Demeule B, Yadav S. Understanding Particle Formation: Solubility of Free Fatty Acids as Polysorbate 20 Degradation Byproducts in Therapeutic Monoclonal Antibody Formulations. Mol Pharm 2015; 12:3792-804. [DOI: 10.1021/acs.molpharmaceut.5b00310] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nidhi Doshi
- Late Stage Pharmaceutical Development, Genentech Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Barthélemy Demeule
- Late Stage Pharmaceutical Development, Genentech Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Sandeep Yadav
- Late Stage Pharmaceutical Development, Genentech Inc., 1 DNA Way, South San Francisco, California 94080, United States
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17
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Fameau AL, Arnould A, Saint-Jalmes A. Responsive self-assemblies based on fatty acids. Curr Opin Colloid Interface Sci 2014. [DOI: 10.1016/j.cocis.2014.08.005] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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18
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Salentinig S, Phan S, Darwish TA, Kirby N, Boyd BJ, Gilbert EP. pH-responsive micelles based on caprylic acid. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:7296-7303. [PMID: 24905895 DOI: 10.1021/la500835e] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Free fatty acids play a vital role as fuel for cells and in lipid metabolism. During lipid digestion in the gastrointestinal tract, triglycerides are hydrolyzed, resulting in free fatty acid and monoglyceride amphiphilic products. These components, together with bile salts, are responsible for the transport of lipids and poorly water-soluble nutrients and xenobiotics from the intestine into the circulatory system of the body. In this study, we show that the self-assembly of digestion products from medium-chain triglycerides (tricaprylin) in combination with bile salt and phospholipid is highly pH-responsive. Individual building blocks of caprylic acid within the mixed colloidal structures are mapped using a combination of small-angle X-ray and neutron scattering combined with both solvent contrast variation and selective deuteration. Modeling of the scattering data shows transitions in the size and shape of the micelles in combination with a transfer of the caprylic acid from the core of the micelles to the shell or into the bulk water upon increasing pH. The results help to understand the process of lipid digestion with a focus on colloidal structure formation and transformation for the delivery of triglyceride lipids and other hydrophobic functional molecules.
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Affiliation(s)
- Stefan Salentinig
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University (Parkville Campus) , 381 Royal Parade, Parkville, VIC 3052, Australia
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19
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Teixeira VH, Vila-Viçosa D, Baptista AM, Machuqueiro M. Protonation of DMPC in a Bilayer Environment Using a Linear Response Approximation. J Chem Theory Comput 2014; 10:2176-84. [DOI: 10.1021/ct5000082] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Vitor H. Teixeira
- Centro
de Química e Bioquímica, Departamento de Química
e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Diogo Vila-Viçosa
- Centro
de Química e Bioquímica, Departamento de Química
e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - António M. Baptista
- Instituto
de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Miguel Machuqueiro
- Centro
de Química e Bioquímica, Departamento de Química
e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
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20
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Jung D, Jeon H, Kwon Y. Electrochemical analysis on the effect of ionic environment change on interfacial reaction kinetics. J Electroanal Chem (Lausanne) 2014. [DOI: 10.1016/j.jelechem.2014.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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21
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Qamhieh K, Amleh M, Khaleel M. Effect of Discrete Macroion Charge Distributions on Electric Double Layer of a Spherical Macroion. J DISPER SCI TECHNOL 2013. [DOI: 10.1080/01932691.2012.751878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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22
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Nordgård EL, Ahmad J, Simon S, Sjöblom J. Oil-Water Partitioning of a Synthetic Tetracarboxylic Acid as a Function of pH. J DISPER SCI TECHNOL 2012. [DOI: 10.1080/01932691.2011.579836] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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23
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24
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Morrow BH, Wang Y, Wallace JA, Koenig PH, Shen JK. Simulating pH Titration of a Single Surfactant in Ionic and Nonionic Surfactant Micelles. J Phys Chem B 2011; 115:14980-90. [DOI: 10.1021/jp2062404] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
| | | | | | - Peter H. Koenig
- Computational Chemistry, Modeling & Simulation GCO, Procter and Gamble, Cincinnati, Ohio, United States
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25
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Boichenko AP, Dung LTK, Loginova LP. Solubilization of Aliphatic Carboxylic Acids (C3-C6) by Sodium Dodecyl Sulfate and Brij 35 Micellar Pseudophases. J SOLUTION CHEM 2011. [DOI: 10.1007/s10953-011-9703-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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26
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Maeda H. Phenomenological approaches in the thermodynamics of mixed micelles with electric charges. Adv Colloid Interface Sci 2010; 156:70-82. [PMID: 20299002 DOI: 10.1016/j.cis.2010.02.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Revised: 02/14/2010] [Accepted: 02/14/2010] [Indexed: 10/19/2022]
Abstract
The stability of mixed micelles in general has been extensively studied by the molecular thermodynamic approaches as well as by the phenomenological or thermodynamic approaches. In this article, phenomenological approaches in the thermodynamics of charged mixed micelles, mostly on ionic/nonionic mixed micelles, are reviewed. The electrostatic interaction constitutes a main contribution to the excess free energy per monomer (in kT unit) g(ex) in the case of ionic/nonionic mixed micelles and the corresponding contribution is generally negative, known as the electric synergism. The origin of the electric synergism is shown to reside in positive curvatures of g(ex,el) (the electric part of g(ex)) when plotted against the mole fraction of the ionic species x. Two types of the micellar Gibbs-Duhem (MGD) relations with (type 1) or without (type 2) the contribution from counterions are discussed to clarify various confusions found in the literature. Effects of varying ionic strengths with the micelle composition in the case of charged mixed micelles without any supporting electrolyte are discussed and a relevant way to correct for the effects is proposed. For ionic/nonionic mixed micelles, the regular solution model (RSM) and some two-parameter models to overcome the limitations inherent to the RSM are discussed. For mixed micelles subject to type 2 MGD relation, hydrogen ion titrations could provide g(el) experimentally just as in the case of linear polyelectrolytes and for those micelles subject to RSM, the titration curve becomes a straight line. Useful information is presented originating from the thermodynamic analysis on the difference of the intrinsic proton dissociation constants between the micelle and the monomer. An analytical expression of the dependence of the degree of counterion binding on x is discussed in comparison with the molecular thermodynamic results. The Corrin-Harkins relation is compared with the degree of counterion binding for ionic/nonionic mixed micelles. Mixed micelles in the concentration range higher than the critical micelle concentration (cmc) are discussed for three cases, the general method of Funasaki-Hada, the ideal mixing case, and the RSM.
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27
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Pallavicini P, Diaz-Fernandez YA, Pasotti L. Micelles as nanosized containers for the self-assembly of multicomponent fluorescent sensors. Coord Chem Rev 2009. [DOI: 10.1016/j.ccr.2008.11.010] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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28
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Pallavicini P, Diaz-Fernandez YA, Pasotti L. Smoothly shifting fluorescent windows: a tunable “off-on-off” micellar sensor for pH. Analyst 2009; 134:2147-52. [DOI: 10.1039/b913195g] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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29
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Mohr A, Pozo Vila T, Korth HG, Rehage H, Sustmann R. HydrophobicN-Diazeniumdiolates and the Aqueous Interface of Sodium Dodecyl Sulfate (SDS) Micelles. Chemphyschem 2008; 9:2397-405. [DOI: 10.1002/cphc.200800399] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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30
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Interaction Between an Anionic and an Amphoteric Surfactant. Part I: Monomer–Micelle Equilibrium. J SURFACTANTS DETERG 2008. [DOI: 10.1007/s11743-008-1080-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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31
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Protolytic equilibrium in lyophilic nanosized dispersions: Differentiating influence of the pseudophase and salt effects. PURE APPL CHEM 2008. [DOI: 10.1351/pac200880071459] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The so-called apparent ionization constants of various acids (mainly indicator dyes) in versatile organized solutions are analyzed. Aqueous micellar solutions of colloidal surfactants and related lyophilic colloidal systems display a strong differentiating influence on the acidic strength of indicators located in the dispersed pseudophase, i.e., non-uniform changes of pKa on going from water to the given system. This concept allows the influence of such media on acid-base properties of dissolved reagents to be rationalized. It is demonstrated that the differentiating phenomenon is the main reason for limitation of the common electrostatic model of acid-base interactions, and is the principal hindrance to exact evaluations of the interfacial electrical potentials of ionic micelles by means of acid-base indicators. Salt effects, i.e., the influence of supporting electrolytes on the apparent ionization constants of acid-base indicators in the Stern region of ionic micelles, are considered. These salt effects can be conventionally divided into two kinds, namely, general (normal) and special (specific) effects. While the first type adds up to screening of the surface charge, the second one consists in micellar transitions caused by hydrophobic counterions.
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32
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Mchedlov-Petrossyan NO, Vodolazkaya NA, Yakubovskaya AG, Grigorovich AV, Alekseeva VI, Savvina LP. A novel probe for determination of electrical surface potential of surfactant micelles:N,N'-di-n-octadecylrhodamine. J PHYS ORG CHEM 2007. [DOI: 10.1002/poc.1150] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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33
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Semashko OV, Brodskaya EN. Simulation of the electrical double layer of a macroion with different counterion charges. COLLOID JOURNAL 2006. [DOI: 10.1134/s1061933x06050140] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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34
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Souza TP, Zanette D, Kawanami AE, de Rezende L, Ishiki HM, do Amaral AT, Chaimovich H, Agostinho-Neto A, Cuccovia IM. pH at the micellar interface: Synthesis of pH probes derived from salicylic acid, acid–base dissociation in sodium dodecyl sulfate micelles, and Poisson–Boltzmann simulation. J Colloid Interface Sci 2006; 297:292-302. [PMID: 16337218 DOI: 10.1016/j.jcis.2005.10.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2005] [Revised: 10/10/2005] [Accepted: 10/13/2005] [Indexed: 11/23/2022]
Abstract
The study of the H+ concentration at the micellar interface is a convenient system for modeling the distribution of H+ at interfaces. We have synthesized salicylic acid derivatives to analyze the proton dissociation of both the carboxylic and phenol groups of the probes, determining spectrophotometrically the apparent pK(a)'s (pK(ap)) in sodium dodecyl sulfate, SDS, micelles with and without added salt. The synthesized probes were 2-hydroxy-5-(2-trimethylammoniumacetyl)benzoate; 2-hydroxy-5-(2-dimethylhexadecylammoniumacetyl)benzoate; 2-hydroxy-5-(2-dimethylhexadecylammoniumhexanoyl)benzoate; 2-hydroxy-5-(2-dimethylhexadecylammoniumundecanoyl)benzoate; 2-hydroxy-5-acetylbenzoic acid; and 2-hydroxy-5-dodecanoylbenzoic acid. Upon incorporation into SDS micelles the pK(ap)'s of both carboxylic and phenol groups increased by ca. 3 pH units and NaCl addition caused a decrease in the probe-incorporated pK(ap). The experimental results were fitted with a cell model Poisson-Boltzmann (P-B) equation taking in consideration the effect of salt on the aggregation number of SDS and using the distance of the dissociating group as a parameter. The conformations of the probes were analyzed theoretically using two dielectric constants, e.g., 2 and 78. Both the P-B analysis and conformation calculations can be interpreted by assuming that the acid groups dissociate very close to, or at, the interface. Our results are consistent with the assumption that the intrinsic pK(a)'s of both carboxylic and phenol groups of the salicylic acid probes used here can be taken as those in water. Using this assumption the micellar and salt effects on the pK(ap)'s of the (trialkylammonium)benzoate probes were described accurately using a cell model P-B analysis.
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Affiliation(s)
- T P Souza
- Departamento de Bioquímica, Universidade de São Paulo, São Paulo, Brazil
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35
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Söderman O, Jönsson B, Olofsson G. Titration of Fatty Acids Solubilized in Cationic and Anionic Micelles. Calorimetry and Thermodynamic Modeling. J Phys Chem B 2006; 110:3288-93. [PMID: 16494342 DOI: 10.1021/jp056861h] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The electrostatic properties of charged surfactant micelles are investigated through titrations of fatty acid probes solubilized in the micelles. The titration process is followed by means of calorimetric measurements and by determining the pH values as a function of added base. This approach yields a complete thermodynamic description of the titration process. In particular, we find that the process is endothermic at 298 K. This is contrary to the titration of carboxylic acids in water, where DeltaH is approximately 0. To identify the main effect underlying the difference in DeltaH between titration in a micelle and water, a thermodynamic model has been developed which focuses on the transfer properties of charged and uncharged species from bulk water to the surface of a micelle and which incorporates a dielectric discontinuity at the micellar surface. The model relies on the use of the Poisson-Boltzmann equation which is solved using a finite element method. Experimental results and the model calculations imply that the dielectric discontinuity at (or near) the micellar surface plays a major role and hence must be included when analyzing the titration behavior of an acid functionality at the surface of a charged micelle.
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Affiliation(s)
- Olle Söderman
- Physical Chemistry 1, P.O. Box 124, S-221 00 Lund, Sweden.
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Qamhieh K, Linse P. Effect of discrete macroion charge distributions in solutions of like-charged macroions. J Chem Phys 2005; 123:104901. [PMID: 16178618 DOI: 10.1063/1.1979496] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The effect of replacing the conventional uniform macroion surface charge density with discrete macroion charge distributions on structural properties of aqueous solutions of like-charged macroions has been investigated by Monte Carlo simulations. Two discrete charge distributions have been considered: point charges localized on the macroion surface and finite-sized charges protruding into the solution. Both discrete charge distributions have been examined with fixed and mobile macroion charges. Different boundary conditions have been applied to examine various properties. With point charges localized on the macroion surface, counterions become stronger accumulated to the macroion and the effect increases with counterion valence. As a consequence, with mono- and divalent counterions the potential of mean force between two macroions becomes less repulsive and with trivalent counterions more attractive. With protruding charges, the excluded volume effect dominates over the increased correlation ability; hence the counterions are less accumulated near the macroions and the potential of mean force between two macroions becomes more repulsive/less attractive.
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Affiliation(s)
- Khawla Qamhieh
- Physics Department, College of Science and Technology, Al-Quds University, Jerusalem, Palestine.
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Gilman JB, Eliason TL, Fast A, Vaida V. Selectivity and stability of organic films at the air–aqueous interface. J Colloid Interface Sci 2004; 280:234-43. [PMID: 15476795 DOI: 10.1016/j.jcis.2004.07.019] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2004] [Accepted: 07/23/2004] [Indexed: 11/15/2022]
Abstract
It has recently been determined that organic compounds represent a significant percentage of the composition of certain atmospheric aerosols. Amphiphilic organics, such as fatty acids and alcohols, partition to the interface of aqueous aerosols. In this way, the air-aqueous interface of an aerosol has the ability to act as both a concentrator and a selector of organic surfactants. Isotherms of nonanoic acid, stearic acid, 1-octadecanol, and a binary of mixture of nonanoic and stearic acids were used to infer the packing ability and molecular orientation of the surfactants at the interface. The selectivity of the air-aqueous interface was studied by monitoring the composition of binary organic films as a function of film exposure time. The films were formed, aged, and collected with the use of a Langmuir trough. The composition of the aged film was determined via GC-MS. Surfactants with differing carbon number and chemical functionalities were studied. These included stearic acid, lauric acid, 1-octadecanol, and octadecane. The stability and packing ability of stearic and lauric acid films were examined as a function of subphase pH. The relevance of these findings as they relate to the composition and structure of organic aerosols as well as recent surface-sensitive aerosol field measurements is discussed.
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Affiliation(s)
- J B Gilman
- Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, CO 80309, USA
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38
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Li X, Wettig SD, Verrall RE. Interactions between 12-EOx-12 gemini surfactants and pluronic ABA block copolymers (F108 and P103) studied by isothermal titration calorimetry. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:579-586. [PMID: 15773079 DOI: 10.1021/la0350204] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The interactions between triblock copolymers of poly(ethylene oxide) and poly(propylene oxide), P103 and F108, EO(n)PO(m)EO(n), m = 56 and n = 17 and 132, respectively, and gemini surfactants (oligooxa)-alkanediyl-alpha,omega-bis(dimethyldodecylammonium bromide) (12-EO(x)-12), x = 0-3, have been studied in aqueous solution using isothermal titration calorimetry. The thermograms of F108 as a function of surfactant concentration show one broad peak at polymer concentrations, Cp, < or =0.50 wt %, below the critical micelle concentration (cmc) of the copolymer at 25 degrees C. It is attributed to interactions between the surfactant and the triblock copolymer monomer. The critical aggregation concentration (cac) remains constant while deltaHmax2 and the saturation concentration, C2, increase with increasing copolymer concentration. Analysis of the cac data offers semiquantitative support that the degree of ionization of the surfactant aggregates bound to polymers is likely to be larger than that at the surfactant cmc. In P103 solutions at Cp > or = 0.05 wt %, two peaks appear in the thermograms and they are attributed to the interactions between the gemini surfactant and the micelle or monomeric forms of the copolymer. An origin-based nonlinear fitting program was employed to deconvolute the two peaks and to obtain estimates of peak properties. An estimate of the fraction of copolymer in aggregated form was also obtained. The enthalpy change due to interactions between the surfactants and P103 aggregates is very large compared to values obtained for traditional surfactants. This suggests that extensive reorganization of copolymer aggregates and surrounding solvent occurs during the interaction. Dehydration of the copolymers by the surfactant may also play an important step in the interaction. The endothermic enthalpy change reflecting interactions between the surfactant and polymer decreases more rapidly as the length and hydrophilic character of the spacer increases, suggesting that more favorable interactions occur with the P103 monomers having shorter PEO segments.
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Affiliation(s)
- Xingfu Li
- Department of Chemistry, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan SK S7N 5C9, Canada
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39
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Rakitin AR, Pack GR. Monte Carlo calculations of ion distributions around micelles. Colloids Surf A Physicochem Eng Asp 2003. [DOI: 10.1016/s0927-7757(03)00003-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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40
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Whiddon CR, Bunton CA, Söderman O. Titration of Fatty Acids in Sugar-Derived (APG) Surfactants: A 13C NMR Study of the Effect of Headgroup Size, Chain Length, and Concentration on Fatty Acid pKa at a Nonionic Micellar Interface. J Phys Chem B 2002. [DOI: 10.1021/jp0263875] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Christy R. Whiddon
- Department of Physical Chemistry 1, Lund University, P.O. Box 124, S-221 00 Lund, Sweden, and Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106
| | - Clifford A. Bunton
- Department of Physical Chemistry 1, Lund University, P.O. Box 124, S-221 00 Lund, Sweden, and Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106
| | - Olle Söderman
- Department of Physical Chemistry 1, Lund University, P.O. Box 124, S-221 00 Lund, Sweden, and Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106
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