Block Copolymers of Polyacrilamide and Poly(ethylene oxide) as Nanocarriers for Drug Delivery: Micellization and Bulk Structure

Abstract

The self-assembly of diblock copolymers series (DBC) of polyacrylamide and methoxypoly(ethylen oxide) (MOPEO-b-PAAm) with a variable length of both the blocks were studied in water and water-ethanol solutions. The tendency of DBCs to micellization in water-ethanol mixture grew with increased molecular weights of the blocks. The addition of NaCl resulted in increase of micellar stability, while the introduction of dimethylformamide (DMF) destructed DBC micelles. In DBC bulk structure, MOPEO blocks either lost or considerably reduced their ability of crystallization due to interaction with PAAm blocks. DBC micelles encapsulated anticancer drug doxorubicin (DOX) that led to lowering the crytical micellization concentration.a) The viscosity-average molecular weight of MOPEG from ''Fluka''. b) The weight fraction of MOPEO block in DBC. c) The ratio between the units in PAAm and PEO blocks.