In this research, monometallic and bimetallic nanoparticles of ruthenium and iron were immobilized on ordered mesoporous carbon sphere structures using chemical reduction method, and their peroxidative activity in the oxidation of amine-containing compounds was investigated. At first, resorcinol-formaldehyde polymer spheres were formed using resorcinol and hexamethylenetetramine as a formaldehyde source and Ploxamer-407 triblock copolymer as a soft template. Synthesized polymer spheres were carbonized at 600°C in an inert atmosphere, with the removal of the soft mold, leading to the formation of ordered mesoporous carbon spheres. Monometallic and bimetallic species of ruthenium and iron were immobilized on these carbon spheres using sodium borohydride and chemical reduction method, leading to the construction of monometallic and bimetallic nanozymes. The peroxidase activity of the synthesized structures was eva‎luated using orthophenylene diamine and trimethylbenzidine substrates, the enzymatic kinetic components Vmax and Km of the quasi-peroxidation reaction of iron-ruthenium bimetallic nanozyme were 0.0407μM.s-1 and 0.023mM respectively for the oxidation of orthophenylenediamine substrate and for the oxidation of tetramethylbenzidine substrate 0.0721μM.s-1and 0.043 mM were calculated. The results showed that the iron-containing carbon structure had no peroxidase activity, however, the iron-ruthenium bimetallic structure showed similar and even better activity than the ruthenium-containing counterpart despite the use of less ruthenium. This observation shows the synergistic effects between ruthenium and iron in the synthesized nanozyme.

سياوش كاظمي موحد

عليرضا نجفي چرمهيني

حسين توكل , محمد ديناري