1
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Tyagi G, Torquato LMG, Ahmad Z, Fong R, Cabral JT. How triacylglycerol thermal history impacts film removal by surfactant solution. J Colloid Interface Sci 2024; 670:540-549. [PMID: 38776689 DOI: 10.1016/j.jcis.2024.05.069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 05/02/2024] [Accepted: 05/09/2024] [Indexed: 05/25/2024]
Abstract
HYPOTHESIS The physical and mechanical properties of triacylglycerols (TAGs), or 'fats', depend on their composition and thermal history which, in turn, impact crystal structure and morphology. We examine whether thermal history can be mechanistically related to film removal by a surfactant solution. EXPERIMENTS Model TAG mixtures, comprising triolein:tripalmitin:tristearin 0.5:0.3:0.2, were subjected to a range of cooling profiles from the melt (0.5-80°C/min, Newtonian and annealed), and the resulting solid films characterised by microscopy, X-ray diffraction, infrared spectroscopy, and contact angle measurements. Film removal from a model glass substrate by an aqueous surfactant solution of sodium dodecylsulphate and dodecyldimethylamine oxide at room temperature fixed at 25°C was examined under quiescent flow conditions. FINDINGS Quantitative relations are established between TAG cooling profile, crystal structure and morphology, surface energy γSFE, and removal (or 'cleaning'). In general, films cooled slowly from the melt yield heterogeneous morphologies with predominantly β1' phase, higher polar γSFE, and faster removal timescales. By contrast, rapid cooling results in homogeneous films, rich in β2' phase, low polar γSFE, and long removal times. Our results elucidate the non-trivial impact of TAG thermal history, connecting the multiscale semi-crystalline structure to surface energy, and eventually to film delamination by micellar solutions.
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Affiliation(s)
- Gunjan Tyagi
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, United Kingdom
| | - Luis M G Torquato
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, United Kingdom
| | - Zain Ahmad
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, United Kingdom
| | - Rebecca Fong
- Procter & Gamble, Newcastle Innovation Centre, Newcastle-Upon-Tyne NE12 9TS, United Kingdom
| | - João T Cabral
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, United Kingdom.
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2
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Kleinheins J, Marcolli C, Dutcher CS, Shardt N. A unified surface tension model for multi-component salt, organic, and surfactant solutions. Phys Chem Chem Phys 2024; 26:17521-17538. [PMID: 38884303 PMCID: PMC11202313 DOI: 10.1039/d4cp00678j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 06/04/2024] [Indexed: 06/18/2024]
Abstract
Despite the fact that the surface tension of liquid mixtures is of great importance in numerous fields and applications, there are no accurate models for calculating the surface tension of solutions containing water, salts, organic, and amphiphilic substances in a mixture. This study presents such a model and demonstrates its capabilities by modelling surface tension data from the literature. The presented equations not only allow to model solutions with ideal mixing behaviour but also non-idealities and synergistic effects can be identified and largely reproduced. In total, 22 ternary systems comprising 1842 data points could be modelled with an overall root mean squared error (RMSE) of 3.09 mN m-1. In addition, based on the modelling of ternary systems, the surface tension of two quaternary systems could be well predicted with RMSEs of 1.66 mN m-1 and 3.44 mN m-1. Besides its ability to accurately fit and predict multi-component surface tension data, the model also allows to analyze the nature and magnitude of bulk and surface non-idealities, helping to improve our understanding of the physicochemical mechanisms that influence surface tension.
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Affiliation(s)
- Judith Kleinheins
- Institute for Atmospheric and Climate Science, ETH Zürich, Universitätstrasse 16, 8092 Zürich, Switzerland.
| | - Claudia Marcolli
- Institute for Atmospheric and Climate Science, ETH Zürich, Universitätstrasse 16, 8092 Zürich, Switzerland.
| | - Cari S Dutcher
- Department of Mechanical Engineering and Department of Chemical Engineering and Materials Science, University of Minnesota, Twin Cities, Minneapolis, MN 55455, USA
| | - Nadia Shardt
- Department of Chemical Engineering, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway
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3
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Torquato LM, Tyagi G, Sharratt WN, Ahmad Z, Mahmoudi N, Gummel J, Robles ESJ, Cabral JT. Concentration Dependent Asymmetric Synergy in SDS-DDAO Mixed Surfactant Micelles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:7433-7443. [PMID: 38532537 PMCID: PMC11008254 DOI: 10.1021/acs.langmuir.3c03900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 03/04/2024] [Accepted: 03/11/2024] [Indexed: 03/28/2024]
Abstract
We investigate the structure and interactions of a model anionic/amphoteric mixed surfactant micellar system, namely, sodium dodecyl sulfate (SDS) and N,N-dimethyldodecylamine N-oxide (DDAO), employing SANS, FTIR, DLS, and pH measurements, in the range 0.1-100 mM total surfactant concentration and 0-100% DDAO. Increasing surfactant concentration is found to elongate the prolate ellipsoid micelles (RPolar ∼ 25-40 Å), accompanied by up to a 6-fold increase in micellar charge. The surfactant synergy, in terms of micellar charge and size, diffusion coefficient, solution pH, and headgroup interactions, was found to vary with concentration. At lower concentrations (≤50 mM), the SDS-DDAO ratio of maximum synergy is found to be asymmetric (at 65-85% DDAO), which is rationalized using regular solution theory, suggesting an equilibrium between Na+ dissociation, DDAO protonation, and counterion concentration. At higher concentrations, maximum synergy shifts toward the equimolar ratio. Overall, our study expands and unifies previous reports, providing a comprehensive understanding for this model, synergetic mixed micellar system.
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Affiliation(s)
- Luis M.
G. Torquato
- Department
of Chemical Engineering, Imperial College
London, London SW7 2AZ, U.K.
| | - Gunjan Tyagi
- Department
of Chemical Engineering, Imperial College
London, London SW7 2AZ, U.K.
| | - William N. Sharratt
- Department
of Chemical Engineering, Imperial College
London, London SW7 2AZ, U.K.
| | - Zain Ahmad
- Department
of Chemical Engineering, Imperial College
London, London SW7 2AZ, U.K.
| | - Najet Mahmoudi
- ISIS
Neutron and Muon Source, Rutherford Appleton Laboratory, Didcot OX11 0QX, United Kingdom
| | - Jérémie Gummel
- Procter
& Gamble, Brussels Innovation Centre, Temselaan 100, 1853 Strombeek-Bever, Belgium
| | - Eric S. J. Robles
- Procter
& Gamble, Newcastle Innovation Centre, Newcastle upon Tyne NE12
9TS, United Kingdom
| | - João T. Cabral
- Department
of Chemical Engineering, Imperial College
London, London SW7 2AZ, U.K.
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4
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El Haber M, Ferronato C, Giroir-Fendler A, Fine L, Nozière B. Salting out, non-ideality and synergism enhance surfactant efficiency in atmospheric aerosols. Sci Rep 2023; 13:20672. [PMID: 38001267 PMCID: PMC10673862 DOI: 10.1038/s41598-023-48040-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 11/21/2023] [Indexed: 11/26/2023] Open
Abstract
In Earth's atmosphere, the surface tension of sub-micron aerosol particles is suspected to affect their efficiency in becoming cloud droplets. But this quantity cannot be measured directly and is inferred from the chemical compounds present in aerosols. Amphiphilic surfactants have been evidenced in aerosols but experimental information on the surface properties of their mixtures with other aerosol components is lacking. This work explores experimentally the surface properties of aqueous mixtures of amphiphilic surfactants (SDS, Brij35, TritonX100, TritonX114, and CTAC) with inorganic salts (NaCl, (NH4)2SO4) and soluble organic acids (oxalic and glutaric acid) using pendant droplet tensiometry. Contrary to what could be expected, inorganic salts and organic acids systematically enhanced the efficiency of the surfactants rather than reduced it, by further lowering the surface tension and, in some cases, the CMC. Furthermore, all the mixtures studied were strongly non-ideal, some even displaying some synergism, thus demonstrating that the common assumption of ideality for aerosol mixtures is not valid. The molecular interactions between the mixture components were either in the bulk (salting out), in the mixed surface monolayer (synergy on the surface tension) or in the micelles (synergy on the CMC) and need to be included when describing such aerosol mixtures.
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Affiliation(s)
- Manuella El Haber
- Universite Claude Bernard Lyon 1, IRCELYON UMR 5256 CNRS, 69622, Villeurbanne, France
| | - Corinne Ferronato
- Universite Claude Bernard Lyon 1, IRCELYON UMR 5256 CNRS, 69622, Villeurbanne, France
| | - Anne Giroir-Fendler
- Universite Claude Bernard Lyon 1, IRCELYON UMR 5256 CNRS, 69622, Villeurbanne, France
| | - Ludovic Fine
- Universite Claude Bernard Lyon 1, IRCELYON UMR 5256 CNRS, 69622, Villeurbanne, France
| | - Barbara Nozière
- KTH Royal Institute of Technology, 100 44, Stockholm, Sweden.
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5
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Donina L, Porcar L, Cabral JT. Composition and temperature effects on the solution structure of SDS/octanol/brine by SANS, NMR and microscopy. SOFT MATTER 2023; 19:8542-8551. [PMID: 37899739 DOI: 10.1039/d3sm01098h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/31/2023]
Abstract
We investigate the solution structures of model sodium dodecyl sulfate/octanol/brine ternary mixtures across the lamellar (Lα), vesicle (L4) and micellar (L1) phases employing small angle neutron scattering (SANS), optical microscopy and nuclear magnetic resonance (NMR). Specifically, we examine the effect of co-surfactant octanol (0.2-9.48 w/v%) and temperature (25-65 °C) along dilution lines at fixed octanol : SDS ratios (0.08-1.21). A transition from Lα to sponge phase (L3) above 35 °C is found along the octanol : SDS = 1.21 isopleth, with phase coexistence above ϕ ≈ 0.14 weight fraction of surfactant and co-surfactant. The lamellar bilayers swell upon dilution, with an approximately linear increase of d-spacing, accompanied by a decrease of the Caillé parameter, indicative of greater membrane rigidity. At a lower octanol : SDS ratio of 0.62, coexistence of oblate micelles and vesicles is observed with preferential formation of vesicles at low concentrations. Dilution of the L1 phase, along octanol : SDS = 0.08, results in elongated micelles, as the NaCl : SDS ratio increases, while higher temperatures favour the formation of less elongated micelles. Our results provide a detailed map of the equilibrium structures found in the Lα vicinity of this extensively investigated flow-responsive surfactant system.
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Affiliation(s)
- Liva Donina
- Department of Chemical Engineering, Imperial College London, UK.
| | - Lionel Porcar
- Institut Laue-Langevin, 71 Avenue des Martyrs, B.P. 156, F-38042 Grenoble CEDEX, France
| | - João T Cabral
- Department of Chemical Engineering, Imperial College London, UK.
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6
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Torquato LMG, Hélaine N, Cui Y, O'Connell R, Gummel J, Robles ESJ, Jacob D, Cabral JT. Microfluidic in-line dynamic light scattering with a commercial fibre optic system. LAB ON A CHIP 2023; 23:2540-2552. [PMID: 37185587 DOI: 10.1039/d3lc00062a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
We report the coupling of dynamic light scattering (DLS) in microfluidics, using a contact-free fibre-optic system, enabling the under-flow characterisation of a range of solutions, dispersions, and structured fluids. The system is evaluated and validated with model systems, specifically micellar and (dilute) polymer solutions, and colloidal dispersions of different radii (∼1-100 nm). A systematic method of flow-DLS analysis is examined as a function of flow velocity (0-16 cm s-1), and considerations of the relative contribution of 'transit' and 'Brownian' terms enable the identification of regions where (i) a quiescent approximation suffices, (ii) the flow-DLS framework holds, as well as (iii) where deviations are found, until eventually (iv) the convection dominates. We investigate practically relevant, robust setups, namely that of a capillary connected to microdevice, as well as direct measurement on a glass microdevice, examining the role of capillary dimensions and challenges of optical alignment. We conclude with a demonstration of a continuous flow measurement of a binary surfactant/salt solution, whose micellar dimensions vary with composition, characterised with hundreds of data points (every ∼5 s) and adequate statistics, within a few minutes.
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Affiliation(s)
- Luis M G Torquato
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
| | - Nelson Hélaine
- CNRS UMR 5623, Laboratoire des IMRCP, Universite Paul Sabatier, Toulouse, France
| | - Yufan Cui
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
| | - Roisin O'Connell
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
| | - Jérémie Gummel
- Procter & Gamble, Brussels Innovation Centre, Temselaan 100, 1853 Strombeek-Bever, Belgium
| | - Eric S J Robles
- Procter & Gamble, Newcastle Innovation Centre, Newcastle upon Tyne NE12 9TS, UK
| | - David Jacob
- Cordouan Technologies, 11 Avenue Canteranne, 33600 Pessac, France
| | - João T Cabral
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
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7
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Lai N, Zhang C, Wang J, Tang L, Ye Z. Effects of Different Gases on the Molecular Behavior of Alkyl Glycosides at Gas/Liquid Interface and Foam Stability. ChemistrySelect 2022. [DOI: 10.1002/slct.202203090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Nanjun Lai
- School of Chemistry and Chemical Engineering Southwest Petroleum University Chengdu 610500 People's Republic of China
- Oil & Gas Field Applied Chemistry Key Laboratory of Sichuan Province Southwest Petroleum University Chengdu 610500 People's Republic of China
- The key laboratory of well stability and fluid & rock mechanics in Oil and gas reservoir of Shaanxi Province Xi'an Shiyou University Xi'an 710065 People's Republic of China
| | - Chengbin Zhang
- School of Chemistry and Chemical Engineering Southwest Petroleum University Chengdu 610500 People's Republic of China
| | - Junqi Wang
- The key laboratory of well stability and fluid & rock mechanics in Oil and gas reservoir of Shaanxi Province Xi'an Shiyou University Xi'an 710065 People's Republic of China
| | - Lei Tang
- Sichuan Ruidong Technology Co., LTD People's Republic of China
| | - Zhongbin Ye
- School of Chemistry and Chemical Engineering Southwest Petroleum University Chengdu 610500 People's Republic of China
- Oil & Gas Field Applied Chemistry Key Laboratory of Sichuan Province Southwest Petroleum University Chengdu 610500 People's Republic of China
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8
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Scheuing DR. Fourier transform infrared spectroscopy in surfactant science: A personal view. J SURFACTANTS DETERG 2022. [DOI: 10.1002/jsde.12644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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9
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Stancheva TN, Georgiev MT, Radulova GM, Danov KD, Marinova KG. Rheology of saturated micellar networks: Wormlike micellar solutions vs. bicontinuous micellar phases. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.129927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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10
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Masalci O. The characterization of hexagonal lyotropic liquid crystal nanostructure: effects of polymer tail length. Colloid Polym Sci 2022. [DOI: 10.1007/s00396-022-05031-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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11
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Tyagi G, Sharratt WN, Erikson S, Seddon D, Robles ESJ, Cabral JT. Solution Structures of Anionic-Amphoteric Surfactant Mixtures near the Two-Phase Region at Fixed pH. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:7198-7207. [PMID: 35658451 PMCID: PMC9202344 DOI: 10.1021/acs.langmuir.2c00527] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 05/25/2022] [Indexed: 06/15/2023]
Abstract
We examine the solution structures in a mixed surfactant system of sodium dodecyl sulfate (SDS) and N,N-dimethyldodecylamine N-oxide (DDAO) in water, on both sides of the two-phase boundary, employing dynamic light scattering, small-angle neutron scattering, and Fourier transform infrared spectroscopy. The precipitate phase boundary was accessed by lowering pH to 8, from its floating pH 9.5 value, and was experimentally approached from the monomeric and micellar regions in three ways: at fixed DDAO or SDS concentrations and at a fixed (70:30) SDS:DDAO molar ratio. We characterize the size, shape, and interactions of micelles, which elongate approaching the boundary, leading to the formation of disk-like aggregates within the biphasic region, coexisting with micelles and monomers. Our data, from both monomeric and micellar solutions, indicate that the two phase structures formed are largely pathway-independent, with dimensions influenced by both pH and mixed surfactant composition. Precipitation occurs at intermediate stoichiometries with a similar SDS:DDAO ratio, whereas asymmetric stoichiometries form a re-entrant transition, returning to the mixed micelle phase. Overall, our findings demonstrate the effect of stoichiometry and solution pH on the synergistic interaction of mixed surfactants and their impact on phase equilibrium and associated micellar and two-phase structures.
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Affiliation(s)
- Gunjan Tyagi
- Department
of Chemical Engineering, Imperial College
London, London, SW7 2AZ, UK
| | - William N. Sharratt
- Department
of Chemical Engineering, Imperial College
London, London, SW7 2AZ, UK
| | - Sofia Erikson
- Department
of Chemical Engineering, Imperial College
London, London, SW7 2AZ, UK
| | - Dale Seddon
- Department
of Chemical Engineering, Imperial College
London, London, SW7 2AZ, UK
| | - Eric S. J. Robles
- The
Procter & Gamble Company, Newcastle Innovation Centre, Newcastle-Upon-Tyne NE12
9TS, UK
| | - João T. Cabral
- Department
of Chemical Engineering, Imperial College
London, London, SW7 2AZ, UK
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12
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Thompson KD, Danielson EP, Peterson KN, Nocevski NO, Boock JT, Berberich JA. The Amphoteric Surfactant N, N-Dimethyldodecylamine N-Oxide Unfolds β-Lactoglobulin above the Critical Micelle Concentration. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:4090-4101. [PMID: 35325533 DOI: 10.1021/acs.langmuir.2c00172] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Understanding the interactions between surfactants and proteins is important for the formulation of consumer products as surfactant binding can alter protein activity and stability. Additionally, the structure of the protein-surfactant complex can influence surface activity, which is important for emulsion and foam development. N,N-Dimethyldodecylamine N-oxide (DDAO) is an amphoteric surfactant that is nonionic at high pH. It is often used as a foam booster in detergent formulations and for the extraction of membrane proteins. In this study, a variety of biophysical characterization methods was used to investigate the impact of DDAO at pH 8 on the structure of the globular protein β-lactoglobulin (βLG). Pyrene fluorescence and surface tension studies show that βLG had minimal impact on the critical micelle concentration (CMC) of DDAO, while fluorescence and circular dichroism spectroscopy found unfolding of βLG at concentrations of DDAO greater than the CMC. Small-angle X-ray scattering results confirm changes in the structure of βLG at DDAO concentrations above the CMC. Taken together, DDAO behaves like nonionic and zwitterionic surfactants below its CMC with limited interaction with βLG, while it induces protein unfolding at concentrations higher than the CMC, resulting in a protein-surfactant complex structure that resembles a protein-decorated micelle.
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Affiliation(s)
- Kayla D Thompson
- Department of Chemical, Paper, and Biomedical Engineering, Miami University, Oxford, Ohio 45056, United States
| | - Evan P Danielson
- Department of Chemical, Paper, and Biomedical Engineering, Miami University, Oxford, Ohio 45056, United States
| | - Kerri N Peterson
- Department of Chemical, Paper, and Biomedical Engineering, Miami University, Oxford, Ohio 45056, United States
| | - Nicholas O Nocevski
- Department of Chemical, Paper, and Biomedical Engineering, Miami University, Oxford, Ohio 45056, United States
| | - Jason T Boock
- Department of Chemical, Paper, and Biomedical Engineering, Miami University, Oxford, Ohio 45056, United States
| | - Jason A Berberich
- Department of Chemical, Paper, and Biomedical Engineering, Miami University, Oxford, Ohio 45056, United States
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13
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Wang L, Xu R, Liu R, Ge P, Sun W, Tian M. Self-Assembly of NaOL-DDA Mixtures in Aqueous Solution: A Molecular Dynamics Simulation Study. Molecules 2021; 26:molecules26237117. [PMID: 34885699 PMCID: PMC8659107 DOI: 10.3390/molecules26237117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 11/16/2021] [Accepted: 11/22/2021] [Indexed: 11/17/2022] Open
Abstract
The self-assembly behaviors of sodium oleate (NaOL), dodecylamine (DDA), and their mixtures in aqueous solution were systematically investigated by large-scale molecular dynamics simulations, respectively. The interaction mechanisms between the surfactants, as well as the surfactants and solvent, were revealed via the radial distribution function (RDF), cluster size, solvent-accessible surface area (SASA), hydrogen bond, and non-bond interaction energy. Results showed that the molecules more easily formed aggregates in mixed systems compared to pure systems, indicating higher surface activity. The SASA values of DDA and NaOL decreased significantly after mixing, indicating a tighter aggregation of the mixed surfactants. The RDF results indicated that DDA and NaOL strongly interacted with each other, especially in the mixed system with a 1:1 molar ratio. Compared to van der Waals interactions, electrostatic interactions between the surfactant molecules were the main contributors to the improved aggregation in the mixed systems. Besides, hydrogen bonds were found between NaOL and DDA in the mixed systems. Therefore, the aggregates in the mixed systems were much more compact in comparison with pure systems, which contributed to the reduction of the repulsive force between same molecules. These findings indicated that the mixed NaOL/DDA surfactants had a great potential in application of mineral flotation.
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14
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Abdul Rub M, Azum N, Kumar D, Khan A, Nadeem Arshad M, Asiri AM, Moteb Alotaibi M. Aggregational behaviour of promethazine hydrochloride and TX-45 surfactant mixtures: A multi-techniques approach. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.117558] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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