Block copolymeric micelles of poly(ethylene oxide)-b-poly(glycidyl methacrylate) for pH-triggered drug release

ABSTRACT

A pH-triggered drug release system of poly(ethylene oxide)-b-poly(glycidyl methacrylate) (PEO-b-PGMA) micelles was described. The PEO-b-PGMA block copolymers were synthesized by the reversible addition-fragmentation chain transfer (RAFT) polymerization of GMA with the PEO-macroinitiator. Subsequently, the hydroxyl groups were introduced to the block copolymer by epoxide ring-opening reaction of PGMA parts. The hydrophobic anticancer drug, doxorubicin (DOX), was conjugated to the polymer by acid cleavable hydrazone bonds, resulting in a pH-responsive controlled release system. The block copolymer and core-shell structure of DOX bearing PEO-b-PGMA were characterized by using FT-IR, ¹H NMR, and TEM analyses. The pH-triggered release of DOX from the micellar core was investigated at pH 5.0 and 7.4, indicating a controlled drug delivery characteristic.

KEYWORDS:

• RAFT polymerization
• core-shell
• hydrazone link
• drug release

Funding

This work was supported by the National Research Foundation of Korea (NRF) Grant funded by the Ministry of Education (NRF-2015R1D1A3A01019109).