Redox responsive nanotubes from organometallic polymers by template assisted layer by layer fabrication

Area of Science:

• Materials Science
• Nanotechnology
• Electrochemistry

Background:

• Layer-by-layer (LbL) assembly is a versatile technique for fabricating multilayered nanostructures.
• Organometallic polymers, such as poly(ferrocenylsilane)s (PFS), offer unique redox-responsive properties.
• Controlled molecular delivery systems are crucial for targeted therapies and diagnostics.

Purpose of the Study:

• To fabricate redox-responsive nanotubes using LbL assembly.
• To utilize poly(ferrocenylsilane)s (PFS) as key components for constructing these nanotubes.
• To demonstrate the potential of these nanotubes as platforms for molecular payload release.

Main Methods:

• Template-assisted layer-by-layer (LbL) assembly using charged polyions, including PFS, on porous membranes (anodized alumina, polycarbonate).
• Removal of the template to yield free-standing nanotubes.
• Characterization using fluorescence microscopy, SEM, TEM, EDX, and cyclic voltammetry.
• Fabrication of composite nanotubes incorporating nanoparticles and fluorophore-labeled dextran or quantum dots.

Main Results:

• Successful fabrication of redox-responsive nanotubes with controlled morphology and composition.
• PFS-containing nanotubes exhibited predictable redox-responsive behavior, similar to thin films.
• Demonstrated triggered release of labeled macromolecules from the nanotubes in response to redox stimuli.
• Composite nanotubes with nanoparticles were successfully synthesized, expanding structural versatility.

Conclusions:

• Redox-responsive nanotubes can be effectively fabricated using template-assisted LbL assembly with PFS.
• These nanotubes show promise as advanced platforms for controlled molecular delivery systems.
• The tunable nature of the LbL assembly allows for the incorporation of various payloads, enhancing application scope.