One-pot synthesis of a cellulose-supported CoFe2O4 catalyst for the efficient degradation of sulfamethoxazole.

Cellulose-supported cobalt ferrite (CoFe2O4/RC) was synthesized via a facile one-pot hydrothermal method and demonstrated to be an efficient catalyst to activate peroxymonosulfate (PMS) for the degradation of sulfamethoxazole (SMX). The characterizations of CoFe2O4/RC catalysts revealed that an appropriate particle size of the cellulose support could promote the dispersion of CoFe2O4 nanoparticles and consequently promote the catalytic activity of the resulting CoFe2O4/RC catalysts. The degradation of SMX reached 97.6 % within 20 min at 30 °C with the CoFe2O4/RC/PMS system. The mechanism of SMX degradation over CoFe2O4/RC-activated PMS was studied via EPR, XPS, and quenching tests. The results suggested that 1O2 was the dominant reactive oxygen species and was accompanied by SO4-, OH, and O2- radicals for SMX degradation. The CoFe2O4/RC catalyst exhibited high stability and recyclability and maintained high catalytic activity after five experimental cycles.

Peptide-Mediated Immobilization on Magnetoferritin for Enzyme Recycling.

Ferritin possess favorable properties because its exterior and interior surface can be applied to generate functional nanomaterials, which make them possible for enzyme immobilization and recycling. Here, we report the noncovalent immobilization of a genetically modified ß-glucosidase onto the outer surface of synthetic magnetoferritin through the electrostatic interaction of a heterodimeric coiled-coil protein formed by coils containing lysine residues (K-coils) and coils containing glutamic acid (E-coils). The immobilized enzyme was characterized, and its enzymatic properties were evaluated. Furthermore, reusability of immobilized enzyme was demonstrated in aqueous solution under an applied magnetic field. The results showed that magnetoferritin was successfully prepared and it was an excellent support for enzyme immobilization. After three times usages, the retention rates were 93.75%, 82.5%, and 56.25%, respectively, demonstrating that immobilized enzyme possessed good retention efficiency and could be used as potential carrier for other biomolecules. The strategy of enzyme immobilization developed in this work can be applied, in general, to many other target molecules.