Keto-Functionalized Polymer Scaffolds As Versatile Precursors to Polymer Side Chain Conjugates

Area of Science:

• Polymer Chemistry
• Biomaterials Science
• Drug Delivery Systems

Background:

• Developing functional polymers is crucial for advanced applications like targeted drug delivery.
• Existing polymers often lack efficient methods for precise side-chain modification.
• Novel monomers are needed to create versatile polymeric architectures.

Purpose of the Study:

• To synthesize and characterize a new methacrylate monomer with a reactive ketone side-chain.
• To create a well-defined block copolymer using reversible addition-fragmentation chain transfer (RAFT) polymerization.
• To demonstrate the facile functionalization of the polymer for potential biomedical applications.

Main Methods:

• Synthesis of 2-(4-oxo-pentanoate) ethyl methacrylate (PAEMA) monomer.
• Polymerization of PAEMA via RAFT to achieve narrow molecular weight distribution.
• Chain extension with poly(ethylene glycol methyl ether acrylate) (PEGMA) to form a block copolymer.
• Conjugation of aminooxy-containing molecules to the ketone side-chain.

Main Results:

• Successfully synthesized PAEMA and polymerized it to a polymer with a low polydispersity index (PDI=1.25).
• Synthesized a PAEMA-b-PEGMA block copolymer.
• Achieved high yields of conjugation of small molecules and oligoethylene glycol to the polymer side chains.
• Demonstrated non-cytotoxicity of the oxime-linked tetra(ethylene glycol) polymer on mouse fibroblast cells up to 1 mg/mL.

Conclusions:

• The synthesized PAEMA monomer and its derived polymers offer a versatile platform for polymer functionalization.
• The block copolymer exhibits excellent biocompatibility, indicating its potential for drug delivery.
• The ease of modification suggests utility in developing tailored polymeric medicines.