Ion specific effect, which is also known as Hofmeister effect, has been reported in numerous systems including ionic surfactant aggregates. Acyl amino acid surfactants have attracted growing attentions in the field of novel surfactants research due to their environmentally benign characteristics. The objective of this study was to investigate the effect of different salts containing NH and tetraalkylammonium (TAA), where alkyl = methyl (TMA), ethyl (TEA), and propyl (TPA), cations on the dilational rheological properties of interfacial film are stabilized by potassium N-cocoyl glycinate (KCGl). The interfacial behaviors were studied using oscillating drop shape analysis method. The interfacial tensions (IFTs) and dilational rheological parameters results illustrate that KCGl in the presence of salts has better interfacial activity and stronger intermolecular interaction, indicating that added cations contribute to denser molecular packing at oil-water interface. Ion specific effects were observed in the system. Among the cations, KCGl shows highest dilational modulus in the presence of NH. The overall interaction between cations and headgroups of KCGl decreases in the sequence NH >TMA >TEA ≈TPA, which follows Hofmeister series. The increasing hydrophobicity of TAA prevents the interaction between cations and KCGl's headgroup, and therefore prevent amphiphiles from packing closely at interface. The results present a theoretical origin for useful application of KCGl in cosmetics, petroleum and daily chemical industries.
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http://dx.doi.org/10.5650/jos.ess20031 | DOI Listing |
Food Chem
December 2024
State Key Laboratory of Marine Food Processing & Safety Control, College of Food Science and Engineering, Ocean University of China, Qingdao 266404, China.
The intricate interactions between stevioside (STE) and milk protein (mixtures of whey protein isolate and sodium caseinate, WPI/SC) as well as interfacial stabilization mechanisms were investigated. At the molecular scale, it was observed that the incorporation of the steviol hydrophobic skeleton enhanced the surface hydrophobicity of WPI/SC (from 1560.73 to 2175.
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Instituto de Física, Universidad Nacional Autónoma de México, Ciudad de México, Mexico.
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January 2025
Laboratory of Biobased Chemistry and Technology, Wageningen University, Bornse Weilanden 9, 6708WG Wageningen, The Netherlands. Electronic address:
Hypothesis: Oilseeds use triacylglycerides as main energy source, and pack them into highly stable droplets (oleosomes) to facilitate the triacylglycerides' long-term storage in the aqueous cytosol. To prevent the coalescence of oleosomes, they are stabilized by a phospholipid monolayer and unique surfactant-shaped proteins, called oleosins. In this study, we use state-of-the-art interfacial techniques to reveal the function of each component at the oleosome interface.
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September 2024
Institute of Energy, Peking University, Beijing, P.R. China.
J Colloid Interface Sci
January 2025
Department of Chemical Engineering, The City College of New York, New York, NY, 10031, USA. Electronic address:
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