A dramatic improvement is reported in the stability of colloidal particles when stabilizing surface grafts are systematically shortened from small polymers to single monomers. The colloidal dispersions consist of fluorinated latex particles, exhibiting a weak van der Waals attraction, with grafted steric layers of poly(ethylene glycol) (PEG) of different chain lengths. Using an effective salting-out electrolyte, NaCO, particle aggregates are detected above a threshold salt concentration that is independent of the particle concentration. The results are interpreted in terms of a sudden onset of nondispersibility of single particles, triggered by the solvent not completely wetting particle surfaces. By decreasing the PEG chain length, the threshold salt concentration is found to increase sharply. For grafts with just a single ethylene glycol group, dispersions remain stable up to exceedingly high concentrations of NaCO. However, on removal of the surface coverage altogether, the classical stability behavior of charge-stabilized dispersions is recovered. The behavior can be captured by a simple model that incorporates effective polymer-solvent interactions in the presence of an electrolyte.
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http://dx.doi.org/10.1021/acs.langmuir.9b02093 | DOI Listing |
Sci Rep
January 2025
School of Science, King Mongkut's Institute of Technology Ladkrabang, Bangkok, 10520, Thailand.
A nanoemulsion was fabricated from Cananga odorata essential oil (EO) and stabilized by incorporation of Tween 80 using ultrasonication. The major constituents of the EO were benzyl benzoate, linalool, and phenylmethyl ester. Differing sonication amplitude (20-60%) and time (2-10 min) were assessed for effects on nanoemulsion droplet size and polydispersity index (PI).
View Article and Find Full Text PDFJ Colloid Interface Sci
April 2025
State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China. Electronic address:
Conventional light-driven antimicrobial strategies of zinc oxide (ZnO) are limited by inadequate illumination in dark environments. In this study, carboxylated cellulose nanocrystals (MCNC) mediated flower-like ZnO (C@Z) with self-promoted reactive oxygen species release under dark is fabricated. The adsorption of Zn ions on MCNC prompts the growth of ZnO along the (002) crystal plane, forming a flower-like hybrid with superior dispersibility and oxygen vacancies compared to MCNC-free ZnO, which exposes the (100) plane.
View Article and Find Full Text PDFJ Colloid Interface Sci
April 2025
High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Science, Hefei, Anhui 230031, PR China; University of Science and Technology of China, Hefei, Anhui 230026, PR China. Electronic address:
Synergistic therapy combining photothermal therapy (PTT) and chemodynamic therapy (CDT) has proven to be a highly effective strategy for cancer treatment. However, PTT heavily relies on the accumulation of therapeutic agents at the tumor site. The peroxidase (POD) activity of common catalysts can be rapidly exhausted during the accumulation process, prior to laser intervention, thereby diminishing the synergistic enhancement effect of the combined therapy.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
Federal Institute for Materials Research and Testing (BAM), Division 1.1 - Inorganic Trace Analysis, Richard-Willstätter-Straße 11, Berlin 12489, Germany. Electronic address:
Organotin (OT) compounds, while crucial in many industrial applications, pose substantial risks to the environment and human health. The toxicity and environmental behaviour of OTs depend on their chemical form, i.e.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
Department of Mechanical Engineering and Agrophysics, Faculty of Production and Power Engineering, University of Agriculture in Krakow, Balicka Street 116 B, 30-149 Krakow, Poland.
One of the methods for obtaining zinc oxide nanoparticles (ZnO NPs) is electrochemical synthesis. In this study, the anodic dissolution process of metallic zinc in alcohol solutions of LiCl was used to synthesize ZnO NPs. The products were obtained as colloidal suspensions in an electrolyte solution.
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