The colloidal stability of bare and poly(methyl methacrylate) (PMMA)-grafted silica nanoparticles was studied in 1-alkyl-3-methylimidazolium ([C(n)mim])-based ionic liquids (ILs) with different anionic structures. The theoretical estimation of the colloidal interaction between monodispersed bare silica particles by using the Derjaguin-Landau-Verwey-Overbeek theory indicates that bare silica particles cannot be stabilized and they rapidly form aggregates in all the ILs used in this study. The instability of bare silica particles was experimentally confirmed by dynamic light scattering measurement and in situ transmission electron microscopy observations by utilizing the negligible vapor pressure of ILs. This evidence suggests that electrostatic stabilization is inefficient in ILs because of the high ionic atmosphere and the resulting surface-charge screening. The PMMA-grafted silica particles exhibited long-term colloidal stability in [C(4)mim][PF(6)] and [C(n)mim][NTf(2)], which are compatible with the grafted PMMA. On the other hand, the PMMA-grafted particles could not be stabilized in [C 4mim][BF 4] due to the poor solubility of the grafted PMMA in the IL. Effective steric stabilization is important for obtaining stable colloidal particles in ILs.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/la704066v | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Study on the effect of water content on physical properties of bentonite.
PLoS One
January 2025
Lecturer College of Civil and Traffic Engineering, Henan University of Urban Construction, Ping Dingshan, China.
Moisture content profoundly influences the engineering properties of expansive soil, a critical consideration in various geotechnical applications. This study delves into the intricate relationship between water content and the physical properties of bentonite, a key constituent of expansive soil. Through a comprehensive analysis encompassing fundamental physical properties, rheological characteristics, permeability behavior, and microscopic features, we elucidate the complex interplay between water content and bentonite behavior.
View Article and Find Full Text PDFRobotic Microcapsule Assemblies with Adaptive Mobility for Targeted Treatment of Rugged Biological Microenvironments.
ACS Nano
January 2025
Center for Innovation & Precision Dentistry, School of Dental Medicine, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
Microrobots are poised to transform biomedicine by enabling precise, noninvasive procedures. However, current magnetic microrobots, composed of solid monolithic particles, present fundamental challenges in engineering intersubunit interactions, limiting their collective effectiveness in navigating irregular biological terrains and confined spaces. To address this, we design hierarchically assembled microrobots with multiaxis mobility and collective adaptability by engineering the potential magnetic interaction energy between subunits to create stable, self-reconfigurable structures capable of carrying and protecting cargo internally.
View Article and Find Full Text PDFStability of electrostatically stabilized Pickering emulsion of silica particles and soy hull polysaccharides: Mechanism of pH and ionic strength.
Food Chem
January 2025
College of Food Science and Technology, Bohai University, Jinzhou 121013, China.
To enhance the surface hydrophobicity and emulsification capacity of silica colloidal particles, a natural surface modification of soy hull polysaccharides (SHP) was conducted. Here, the effects of pH and ionic strength on the stability, microstructure and rheological properties of concentrated Pickering emulsions were investigated. Experimental results show emulsions gelled at pH 2, with increasing pH (2-10), SiO-SHP absolute zeta potential (from -19.
View Article and Find Full Text PDFNew Strategy for the Covalent Immobilisation of Phenolic Compounds on Silica Particles to Fight Against Foodborne Pathogens.
Foods
December 2024
Instituto Universitario de Ingeniería de Alimentos-Food UPV, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain.
The immobilisation of essential oil components (EOCs) on food-grade supports is a promising strategy for preserving liquid foods without the drawbacks of direct EOC addition such as poor solubility, high volatility, and sensory alterations. This study presents a novel method for covalently immobilising EOCs, specifically thymol and carvacrol, on SiO particles (5-15 µm) using the Mannich reaction. This approach simplifies conventional covalent immobilisation techniques by reducing the steps and reagents while maintaining antimicrobial efficacy and preventing compound migration.
View Article and Find Full Text PDFUsing the Radial Distribution Function to Analyze Atomic Force Microscopy Images of Colloidal Systems.
Int J Mol Sci
December 2024
Institute of Biomedical Chemistry, Pogodinskaya Str., 10, Moscow 119121, Russia.
Biomacromolecules generally exist and function in aqueous media. Is it possible to estimate the state and properties of molecules in an initial three-dimensional colloidal solution based on the structure properties of biomolecules adsorbed on the two-dimensional surface? Using atomic force microscopy to study nanosized objects requires their immobilization on a surface. Particles undergoing Brownian motion in a solution significantly reduce their velocity near the surface and become completely immobilized upon drying.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!