Natural polyampholyte-based core-shell nanoparticles with N-carboxyethylchitosan-containing core and poly(ethylene oxide) shell.

For the first time, core-shell nanoparticles were prepared from the natural polyampholyte N-carboxyethylchitosan (CECh). This was triggered by polyelectrolyte complex (PEC) formation between CECh and strong polyelectrolyte-containing double hydrophilic block copolymers. Quaternized poly[2-(dimethylamino)ethyl methacrylate]-b-poly(ethylene oxide) (quaternized PDMAEMA-b-PEO) and sodium poly(2-acrylamido-2-methylpropane sulfonate)-b-poly(ethylene oxide) (PAMPSNa-b-PEO) were used as polycation and polyanion, respectively.