Micelleplexes: Complexation of Polyanions with Cationic AB Diblock and ABC Triblock Micelles

The complexation of polyanions with block copolymer micelles that bear cationic charge has been explored, with the overall goal of using micelle templates as a means to control micelleplex size, shape, colloidal stability, and net charge. Polyanions of interest include flexible polystyrene sulfonate and semiflexible DNA (both linear and plasmid), over wide ranges of molar mass. The micelles feature a hydrophobic core (polystyrene or poly-n-butylmethacrylate) and a cationic poly(dimethylaminoethylmethacrylate) corona block. Micelleplex stability and structure are assessed by a combination of turbidimetric titration, dynamic light scattering, and cryogenic transmission electron microscopy. The role of ionic strength in promoting equilibration of micelleplex structure is also investigated. Furthermore, a third, neutral hydrophilic block, either poly(oligoethylene glycol methacrylate) or poly(ethylene glycol), has been added to the micelle corona, to determine whether increased colloidal stability of charge-neutral micelleplexes can be achieved.