Encapsulation of Curcumin by Methoxy Poly(ethylene glycol-b-aromatic anhydride) Micelles

Suitable carrier systems for sustained release of curcumin were studied by using the self-assembled polymeric micelles. Poly(ethylene glycol) methyl ether and poly(aromatic anhydride) were used as the hydrophilic and hydrophobic blocks, respectively, in forming amphiphilic diblock copolymers. Four different types of polymers methoxy poly(ethylene glycol-b-1,3-bis(p-carboxyphenoxy)propane) (mPEG(5000)CPP, mPEG(2000)CPP), methoxy poly(ethylene glycol-b-1,6-bis(p-carboxyphenoxy)hexane) (mPEG(5000)CPH, mPEG(2000)CPH) were synthesized via melt condensation approach. Micelles were formed at very low polymer concentration with stable hydrophobic cores. The particle sizes of micelles remained stable during degradation period. All four different polymeric micelles showed low cytotoxicity toward human fibroblasts cells and can kill cancer cells in very low concentrations. High loading efficiency and drug content were observed in curcumin-loaded micelles. Curcumin showed mild initial burst (30% of drug loading in the first 24 h) when released from the micelles and its release was sustained for at least 18 days. These micelles, especially those of mPEG(5000)CPP, show potential to serve as the delivery vehicles for sustained release of curcumin. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 898-907, 2011