Designing Covalent Organic Framework-Based Light-Driven Microswimmers toward Therapeutic Applications

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Controlled motion and targeted drug delivery in biological environments necessitate advanced micromachine designs.
• Covalent organic frameworks (COFs) present a novel class of nanoporous polymers with potential for biomedical applications.

Purpose of the Study:

• To develop and compare two types of COF-based light-driven microswimmers for drug delivery in biological media.
• To evaluate their efficiency, biocompatibility, and imaging capabilities for therapeutic applications.

Main Methods:

• Synthesis and characterization of spherical TABP-PDA-COF and nanoporous TpAzo-COF particles.
• Assessment of their light-driven motion (phototaxis) in aqueous and cellular media.
• Evaluation of drug loading/release efficiency and in operando imaging capabilities using indocyanine green (ICG).

Main Results:

• Both COF types demonstrated efficient visible-light-driven propulsion and drug carrying capabilities in various biological media.
• Their porous structures facilitated targeted drug loading, including insoluble drugs, with on-demand release.
• ICG loading enabled real-time photoacoustic imaging, optical coherence tomography, and hyperthermia, showcasing their theranostic potential.

Conclusions:

• COF-based microswimmers are promising for targeted drug delivery and theranostics in biological environments, including intraocular fluids.
• Their biocompatibility, tunable properties, and imaging capabilities offer significant advantages for future biomedical applications like retinal drug delivery.