Reducible, dibromomaleimide-linked polymers for gene delivery

Area of Science:

• Polymer Chemistry
• Biomaterials Science
• Gene Therapy

Background:

• Cationic polymers are effective gene transfer vehicles but exhibit cytotoxicity, often linked to molecular weight.
• Rapidly degradable polymers show better mammalian cell tolerance than non-degradable ones.

Purpose of the Study:

• To develop novel, reducible cationic polymers for gene delivery using a dibromomaleimide-alkyne (DBM-alkyne) linker.
• To enable reversible polymer bridging and site-specific functionalization via click chemistry for enhanced gene delivery vehicles.

Main Methods:

• Synthesis of reducible and non-reducible statistical copolymers of (2-dimethylamino)ethyl methacrylate (DMAEMA) and oligo(ethylene glycol)methyl ether methacrylate (OEGMA).
• Evaluation of DNA condensation, size, transfection efficiency, and cytotoxicity of DBM-linked polymers.
• Demonstration of polymer functionalization using azide-alkyne cycloaddition chemistry with an azide-fluorophore.

Main Results:

• Reducible and non-reducible polymers exhibited comparable DNA complexation, size, and transfection efficiencies.
• DBM-linked, reducible polymers demonstrated significantly lower cytotoxicity compared to non-reducible counterparts.
• Click chemistry enabled facile, site-specific functionalization and cellular uptake monitoring.

Conclusions:

• The DBM-alkyne linker provides a reversible strategy for gene delivery polymer design.
• This system allows for orthogonal and site-specific functionalization of gene delivery vehicles.
• Reducible polymers offer a promising approach to mitigate cytotoxicity in gene therapy applications.