We investigate the use of particle hydrophilicity as a tool for emulsion destabilization in Triton-X-100-stabilized hexadecane-in-water emulsions. The hydrophilicity of the particles added to the aqueous phase was found to have a pronounced effect on the stability of the emulsion. Specifically, the addition of hydrophilic fumed silica particles to the aqueous phase resulted in coarsening of the emulsion droplets, with droplet flocculation observed at higher particle concentrations. On the other hand, when partially hydrophobic fumed silica particles were added to the aqueous phase, coarsening of the emulsion droplets was observed at low particle concentrations and phase separation of oil and water was observed at higher particle concentrations. Surface tension and interfacial tension measurements showed significant depletion of the surfactant from the aqueous phase in the presence of the partially hydrophobic particles. The observed changes in the stability of the emulsion and the depletion of the surfactant can be rationalized in terms of changes in the adsorption behavior of the surfactant molecules, from one dominated by hydrogen bonding on hydrophilic particles to one dominated by hydrophobic interactions on partially hydrophobic particles. Our findings also provide, for the first time, an in-depth understanding of antagonistic (destabilizing) effects in mixtures of partially hydrophobic particles and a non-ionic surfactant (Triton X-100) in water.
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http://dx.doi.org/10.1021/acs.langmuir.6b03289 | DOI Listing |
J Am Chem Soc
January 2025
School of Physics and Optoelectronic Engineering, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China.
Colloidal quantum dots (QDs) are promising emitters for biological applications because of their excellent fluorescence, convenient surface modification, and photostability. However, the toxic cadmium composition in the state-of-the-art QDs and their inferior properties in the aqueous phase greatly restrict further use. The performance of water-soluble indium phosphide (InP) QDs lags far behind those of Cd-containing counterparts due to the lack of effective surface protection.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
College of Ocean Food and Biological Engineering, Jimei University, Xiamen 361021, China. Electronic address:
Purple passion fruit peel (PPFP) is a common biomass waste. Meanwhile, hydrothermal carbonization (HTC) is a common technology used for thermal conversion of biomass waste. Herein, the aqueous phase (AP) of PPFP was determined using HTC, and its properties were studied.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics, Research Institute of Aero-Engine, Beihang University, Beijing 100191, China. Electronic address:
Hypothesis: Complex emulsions usually consist of aqueous phases, like oil-in-water-in-oil (o/w/o) and water-in-oil-in-water (w/o/w), serving foundational roles in colloid science. Oil-in-oil-oil (o/o/o) emulsions offer new avenues for non-aqueous reagents but face challenges in balancing the forces between multiple organic phases.
Experiments: In this work, we generate o/o/o emulsions by integrating an AC electric field with a double cross-junction microchannel.
ACS Appl Mater Interfaces
January 2025
School of Chemistry and Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
Hydrogel-based sensors typically demonstrate conspicuous swelling behavior in aqueous environments, which can severely compromise the mechanical integrity and distort sensing signals, thereby considerably constraining their widespread applicability. Drawing inspiration from the multilevel heterogeneous structures in biological tissues, an antiswelling hydrogel sensor endowed with high strength, rapid self-recovery, and low swelling ratio was fabricated through a water-induced phase separation and coordination cross-linking strategy. A dense heterogeneous architecture was developed by the integration of "rigid" quadridentate carboxyl-Zr coordination bonds and "soft" hydrophobic unit-rich regions featuring π-π stacking and cation-π interactions into the hydrogels.
View Article and Find Full Text PDFAnal Chem
January 2025
Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, Pennsylvania 15260, United States.
The nuclear pore complex (NPC) is the proteinous nanopore that solely regulates molecular transport between the nucleus and cytoplasm of a eukaryotic cell. Hypothetically, the NPC utilizes the hydrophobic barriers based on the repeats of phenylalanine-glycine (FG) units to selectively and efficiently transport macromolecules. Herein, we quantitatively assess the hydrophobicity of transport barriers confined in the nanopore by applying scanning electrochemical microscopy (SECM).
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