Design of super-paramagnetic bilayer films based on chitosan and sodium alginate

Bilayer films that combine chitosan and alginate, two natural polysaccharides, magnetic iron oxide nanoparticles (MNPs) were obtained. Physical microscopic observations revealed alginate interact strongly through their surfaces, which is attributed to the formation of a polyelectrolyte complex at interface. The diameter individual MNPs was about 10 nm, although in they appear arranged clusters with sizes ranging from 23 nm several times larger are formed by collapsed particles. All bilayers containing MNP behave as super-paramagnetic materials, exhibiting synergic effects comparison single carbohydrate films. Thus, obtained could find novel interesting applications pH responsiveness systems, pad dressings including hyperthermia, adsorption positive negative charged pollutants, etc.