Self-Assembly and Drug Encapsulation Properties of Biocompatible Amphiphilic Diblock Copolymers

Area of Science:

• Polymer Chemistry
• Biomaterials Science
• Nanotechnology

Background:

• Amphiphilic diblock copolymers offer unique self-assembly properties for advanced applications.
• Poly(2-(methacryloyloxy)ethyl phosphorylcholine) (PMPC) provides biocompatibility due to its zwitterionic phosphorylcholine groups.
• Poly(3-methoxypropyl acrylate) (PMPA) is predominantly hydrophobic yet exhibits biocompatibility.

Purpose of the Study:

• To synthesize and characterize amphiphilic diblock copolymers (M100P) with varying PMPA block lengths.
• To investigate the self-assembly behavior of these copolymers in aqueous solutions.
• To evaluate the potential of M100P aggregates as drug delivery vehicles.

Main Methods:

• Controlled radical polymerization was used to synthesize PMPC-PMPA diblock copolymers.
• Dynamic Light Scattering (DLS) and Transmission Electron Microscopy (TEM) were employed to analyze aggregate morphology.
• Doxorubicin encapsulation efficiency was assessed.

Main Results:

• M100P copolymers with PMPC (DP=100) and PMPA (DP=171 or 552) were successfully synthesized.
• M100P₁₇₁ formed spherical micelles, while M100P₅₅₂ formed vesicles in water.
• Aggregate size and number increased with the PMPA block's degree of polymerization.
• Doxorubicin was effectively encapsulated within the M100P aggregates.

Conclusions:

• M100P amphiphilic diblock copolymers exhibit excellent biocompatibility from both blocks.
• The copolymers self-assemble into distinct nanostructures (micelles and vesicles) based on PMPA block length.
• M100P aggregates demonstrate significant potential for use in drug delivery systems.