In situ synthesis of polysaccharide nanoparticles via polyion complex of carboxymethyl cellulose and chitosan

► Polymer-magnetite hybrid nanoparticles having a semi-IPN structure were prepared by in situ synthesis. ► The polyion complex of carboxymethyl cellulose and chitosan was chemically cross-linked using a bio-based cross-linker, genipin. ► Polymer-magnetite hybrid nanoparticles exhibit responsiveness to a magnetic field. ► Encapsulation of magnetite in nanoparticles improves dispersion stability.