pH-sensitive polymeric micelles for enhanced intracellular anti-cancer drug delivery

Polyion complex (PIC) micelles are expected to be used as nanocarrier for drug delivery. The PIC micelles formed by cationic anti-cancer drug, doxorubicin (DOX) and poly(ethylene glycol)-block-poly(4-vinylbenzylphosphonate) (PEG-b-PVBP) (DOX@PNP) was prepared with different pH conditions and composition ratio of the mixture. DOX and PEG-b-PVBP were spontaneously self-assembled in aqueous solutions into nanoparticles with average size of 45-55 nm over the entire range of the compositions of the mixtures including stoichiometric electroneutral complexes. The DOX@PNP described here would be promising nanocarrier for anti-cancer drug delivery.