Metallic Nanoparticle Block Copoloymer Vesicles with Enhanced Optical Properties

Area of Science:

• Nanotechnology
• Materials Science
• Biomedical Engineering

Background:

• Block co-polymer vesicles offer a stable and biocompatible platform for nanoparticle encapsulation.
• Controlling nanoparticle size and functionalization is crucial for tailoring optical properties.

Purpose of the Study:

• To fabricate and characterize polymer vesicles encapsulating gold and silver nanoparticles.
• To investigate the impact of nanoparticle encapsulation on vesicle structure and optical properties.
• To evaluate the potential of these constructs as plasmon-resonant optical contrast agents.

Main Methods:

• Synthesis of poly(oxyethylene)-poly(butylene) diblock co-polymer vesicles.
• Encapsulation of functionalized silver nanoparticles (1-10 nm) and non-functionalized gold nanoparticles (3.0-5.5 nm).
• Characterization using Transmission Electron Microscopy (TEM) and transmission spectrophotometry.

Main Results:

• Vesicles with a narrow size distribution (~200 nm) were successfully fabricated.
• Silver nanoparticles localized in the membrane, thickening it, while gold nanoparticles were core-encapsulated.
• Significant enhancement of optical properties observed, with plasmon resonance shifting beyond 700 nm.

Conclusions:

• Stable, biocompatible block co-polymer vesicles can effectively encapsulate nanoparticles.
• The fabricated nanostructures exhibit tunable plasmon-resonant optical properties.
• These vesicles hold promise as optical contrast agents for biomedical applications.