Facile synthesis of gold core-polymer shell responsive particles

Area of Science:

• Materials Science
• Nanotechnology
• Polymer Chemistry

Background:

• Developing responsive core-shell nanoparticles is crucial for advanced material applications.
• Poly dimethylaminoethyl methacrylate (pDMAEMA) is a pH-responsive polymer with potential for surface functionalization.
• Gold nanoparticles (AuNPs) offer unique optical properties and a versatile platform for nanoparticle assembly.

Purpose of the Study:

• To explore the physisorption of pDMAEMA onto AuNPs for creating responsive core-shell nanoparticles.
• To determine optimal conditions for dense polymer coverage and stable nanoparticle formation.
• To investigate the responsive and reversible aggregation behavior of the synthesized core-shell nanoparticles.

Main Methods:

• Utilizing pH-driven polymer collapse and adsorption onto gold nanoparticles.
• Employing dynamic light scattering (DLS) and mobility measurements for characterization.
• Conducting potentiometric titrations and UV-Vis spectroscopy (SPR) to assess responsiveness and aggregation.

Main Results:

• Achieved dense coverage of pDMAEMA on AuNPs under specific pH and mixing conditions.
• Demonstrated that core-shell nanoparticles exhibit pH-dependent responsive behavior.
• Observed reversible aggregation of the nanoparticles upon cycling between different pH values.

Conclusions:

• The developed method provides an easy, flexible, and stable approach for producing responsive core-shell nanoparticles.
• End-functional thiol groups on pDMAEMA enhance attachment to gold nanoparticles.
• The synthesized nanoparticles show promising potential as a colloidal coating mechanism due to their stability and responsiveness.