Water-soluble polymer micelles formed from amphiphilic diblock copolymers bearing pendant phosphorylcholine and methoxyethyl groups

Abstract

Amphiphilic diblock copolymers (M98En) composed of hydrophilic poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC, M) and hydrophobic poly(2-methoxyethyl acrylate) (PMEA, E) were prepared via controlled radical polymerization. The degree of polymerization (DP) of the PMPC block was 98, and the DP values of the PMEA block (=n) were 95 and 314. In water, M98En formed micelles with hydrophobic PMEA cores and hydrophilic PMPC shells. The size, density, and aggregation number of M98E314 were larger than those of M98E95 because the hydrophobic interactions became stronger with increasing PMEA block length. A hydrophobic anticancer agent, i.e., doxorubicin, was encapsulated into the core of the polymer micelles to assess the potential of these micelles as carriers in a drug delivery system. Micelles formed from M98En did not interact with proteins in the aqueous solution because the micelle surfaces were covered with biocompatible PMPC shells. Amphiphilic diblock copolymers (M98En) composed of hydrophilic poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) and hydrophobic poly(2-methoxyethyl acrylate) were synthesized via controlled radical polymerization. M98En formed micelles in water, which can encapsulate hydrophobic guest molecules into the core. The micelles did not interact with proteins in an aqueous solution due to the PMPC shells.