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Updated: May 24, 2026
09:27
Encapsulation and Permeability Characteristics of Plasma Polymerized Hollow Particles
Published on: August 16, 2012
Behavior of pH-sensitive core shell particles at the air-water interface.
Mark D'Souza Mathew1, Mohamed S Manga, Timothy N Hunter
1Institute of Particle Science and Engineering School of Process, Environmental and Materials Engineering, University of Leeds, Leeds, United Kingdom. sms5mdm@leeds.ac.uk
Langmuir : the ACS Journal of Surfaces and Colloids
|February 25, 2012
Summary
Responsive polymer-shell nanoparticles adsorb at the air-water interface. Their stability and desorption behavior are controlled by pH-induced changes in the polymer shell
Area of Science:
- Materials Science
- Surface Chemistry
- Colloid Science
Background:
- Core-shell nanoparticles offer tunable properties for interfacial applications.
- Responsive polymer shells enable dynamic control over nanoparticle behavior.
- The air-water interface is a crucial environment for self-assembly and material stabilization.
Purpose of the Study:
- To investigate the interfacial adsorption and stability of latex core-responsive polymer-shell nanoparticles.
- To explore the influence of subphase pH on nanoparticle wetting and interfacial behavior.
- To study the pH-triggered desorption of pre-adsorbed nanoparticles from the air-water interface.
Main Methods:
- Utilizing a Langmuir trough to study adsorption at the air-water interface.
- Analyzing phase transition isotherms to characterize interfacial behavior.
- Manipulating subphase pH to control polymer shell hydration and particle stability.
Main Results:
- Demonstrated pH-dependent adsorption and stability of nanoparticles at the air-water interface.
- Showcased the effect of subphase pH on polymer shell wetting and particle film formation.
- Observed and quantified nanoparticle desorption triggered by pH changes.
Conclusions:
- The pH of the subphase critically influences the stability and adsorption of these nanoparticles at the air-water interface.
- Responsive polymer shells provide a mechanism for controlling nanoparticle interfacial behavior and release.
- These findings are relevant for designing smart materials and controlled delivery systems.
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