A novel structural Fenton-like nanocatalyst with highly improved catalytic performance for generalized preparation of iron oxide@organic dye polymer core-shell nanospheres.

FexOy@FexOy/C nanoparticles with a soap-bubble-like shell have been synthesized, and the materials exhibit excellent Fenton catalytic performance. More importantly, FexOy@FexOy/C nanoparticles as catalysts and precursors could catalyze organic dye molecules to form iron oxide@organic dye polymer core-shell nanospheres.

One-step fabrication of functionalized magnetic adsorbents with large surface area and their adsorption for dye and heavy metal ions.

Functionalized magnetic adsorbents (FMAs) were synthesized by a facile and surfactant-free one-pot solvothermal approach, using iron(III) chloride hexahydrate as the precursor, ethylene glycol as the reducing agent, ammonium acetate, and EDTA-2Na as an electrostatic stabilization agent. The self-assembly process of the functionalized magnetic adsorbents has been investigated and a plausible mechanism is proposed. The resulting functionalized magnetic adsorbents have relatively high specific surface areas (71.6 m(2) g(-1)), excellent magnetic properties and rich functional groups (carboxyl groups, hydroxyl groups and hydrophobic groups). Meanwhile, the resulting FMAs were employed in the adsorption of dyes and heavy metal ions from aqueous solution. Herein, we took two types of typical pollutants, dyes (methylene blue (MB) and malachite green (MG)) and toxic heavy metal ions (Cr(VI) and Pb(II)) as examples of organic and inorganic pollutants in environmental water. The excellent intrinsic properties of the FMAs led to a stronger adsorption ability than a solid Fe3O4 adsorbent for MB, MG, Cr(VI) and Pb(II). Especially, the simultaneous adsorption of the functionalized flower-like magnetic adsorbents for MG and Pb(II) was also determined in a binary system. Finally, it was demonstrated that the resulting flower-like magnetic adsorbents are expected to be a good candidate as an adsorbent for water treatment.

Facile solvothermal synthesis of mesostructured Fe3O4/chitosan nanoparticles as delivery vehicles for pH-responsive drug delivery and magnetic resonance imaging contrast agents.

We report a facile fabrication of a host-metal-guest coordination-bonding system in a mesostructured Fe3O4/chitosan nanoparticle that can act as a pH-responsive drug-delivery system. The mesostructured Fe3O4/chitosan was synthesized by a solvothermal approach with iron(III) chloride hexahydrate as a precursor, ethylene glycol as a reducing agent, ammonium acetate as a porogen, and chitosan as a surface-modification agent. Subsequently, doxorubicin (DOX), acting as a model drug (guest), was loaded onto the mesostructured Fe3O4/chitosan nanoparticles, with chitosan acting as a host molecule to form the NH2-Zn(II)-DOX coordination architecture. The release of DOX can be achieved through the cleavage of coordination bonds that are sensitive to variations in external pH under weakly acidic conditions. The pH-responsive nature of the nanoparticles was confirmed by in vitro releases and cell assay tests. Furthermore, the relaxation efficiency of the nanoparticles as high-performance magnetic resonance imaging contrast agents was also investigated. Experimental results confirm that the synthesized mesostructured Fe3O4/chitosan is a smart nanovehicle for drug delivery owing to both its pH-responsive nature and relaxation efficiency.