Influence of structure and magnetic properties of surface modified nanoparticles for hyperthermia application

We report the study of CoFe2O4 with biopolymers (chitosan and dextran), synthesized via a solvothermal method. The formation of the CoFe2O4 spinel phase has been validated using XRD and Rietveld analyses. The pattern of polyhedral and spherical shapes was observed for uncoated and coated samples using TEM. Mo center dot ssbauer's study revealed the mixed spinel nature of the nanoparticles, in which Fe3+ and Co2+ ions are distributed in both tetrahedral and octahedral sites. The M -H curves obtained at ambient temperature show the typical ferromagnetic behavior for all the magnetic nanoparticles. The surface modification influences the spe-cific loss power (SLP) value of the magnetic nanoparticles. Furthermore, our study revealed that dipole-dipole interactions are responsible for the self-heating behavior. SLP values demonstrated non-monotonic behavior for all the nanoparticle samples, implying that both Ne ' el and Brownian relaxation is the responsible for heat generation in a high viscosity medium.