Magnetic nanoparticles are the good choice for using in MRI as the contrast agent. Iron oxide particles such as magnetite (Fe3O4) or its oxidized form maghemite (γ-Fe2O3) are the most commonly employed in biomedical applications. In this study, we synthesized and optimized the preparation of chitosan manganese-ferrite nanoparticles (CMn-Fe nps) and evaluated its ability for the mice macrophage ...

The influence of surface anisotropy on the magnetization processes of maghemite nanoparticles with ellipsoidal shape is studied by means of Monte Carlo simulations. Radial surface anisotropy is found to favor the formation of hedgehog-like spin structures that become more stable as the surface anisotropy constant at the surface kS is increased form the value at the core. We have studied the cha...

A versatile and straightforward strategy to construct a xanthone skeleton via an intermolecular catalytic coupling of 2-substituted benzaldehydes and a wide range of phenols has been developed. For this purpose, a novel and magnetically recoverable catalyst consisting of copper nanoparticles on nanosized silica coated maghemite in absence of ligand is presented. The reaction proceeds smoothly w...

Monodisperse maghemite nanoparticles, templated in novel, well-defined pyrazole-containing norbornene-based block copolymers, provided a superparamagnetic nanocomposite with high saturation magnetization at room temperature under an applied magnetic field. The synthesis of the polymer nanocomposites and physical, morphological, and magnetic chracaterization of the nanocomposites are reported. M...

Low-temperature oxidation of aqueous magnetite nanoparticles to maghemite has been monitored via the loss of near-IR optical absorbance. The kinetics closely follows the diffusion in a sphere model as suggested by previous literature reports. The temperature dependence of the diffusion constant is described by an Arrhenius equation with an activation energy of 21.0 kcal/mol. No intermediate opt...

Wastewater cleaning strategies based on the adsorption of materials are being increasingly considered, but the wide variety of organic pollutants at low concentrations still makes their removal a challenge. The hybrid material proposed here consists of a zwitterionic polyethylenimine polymer coating a magnetic core. Polyethylenimine is phosphonated at different percentages by a one-step process...

A coarse-grain description of nanocolloidal suspensions in the presence of an added salt is presented here. It enables us to simulate trajectories of the nanoparticles from effective functions that depend on average densities of salt ions. In practice, the ion-averaged effective potential is used as input of a Brownian dynamics (BD) simulation. This potential may be derived by various methods, ...

Method of determining of magnetic moment and size from measurements of dependence of the nonlinear magnetic susceptibility upon magnetic field is proposed, substantiated and tested for superparamagnetic nanoparticles (SPNP) of the "magnetic core-polymer shell" type which are widely used in biomedical technologies. The model of the induction response of the SPNP ensemble on the combined action o...