Fabrication and electrochemical study of monodisperse and size controlled Prussian blue nanoparticles protected by biocompatible polymer

Monodisperse and size controlled Prussian blue (PB) nanoparticles have been synthesized using chitosan as protective matrix. The method depends on electrostatic interactions of Fe(CN)63− ions with cationic chitosan macromolecules followed by the reaction with FeCl2. The observation of transmission electron microscope (TEM) showed that the diameter of these monodisperse nanoparticles ranged from 5 to 20 nm with different chitosan contents. X-ray diffraction (XRD) analysis further identified a face-centered cubic structure of the nanoparticles. Investigations of optical properties of nanoparticles were also conducted with Fourier transform infrared (FT-IR) and Ultra violet/visible (UV–vis) spectroscopy. Moreover, cyclic voltammetry (CV) demonstrated that the chitosan-PB nanoparticles kept their intrinsic electrochemical properties and electrocatalytic activity towards hydrogen peroxide. This method represents a new route for preparing biocompatible Prussian blue nanoparticles that offers control over the size and protection against aggregation.