Self-assembly into magnetic Co3O4 complex nanostructures as peroxidase

Here we reported on the synthesis and characterization of Co3O4 gillyflower-like nanostructures (termed as CGN) with peroxidase-like activity via an L-arginine-assisted hydrothermal synthesis approach. The CON were characterized by a wide range of physicochemical characterization techniques. The temperature-dependence magnetic measurement (M-T) of the CGN shows a very low Neel temperature (T-N) of 10.6K, due to the finite-size scaling effect. The CON catalysed the reaction of peroxidase substrate 3,3',5,5'-tetramethylbenzidine (TMB) to give the same colour changes as horseradish peroxidase (HRP, the most commonly used catalyst in the enzymatic reaction). And the catalysis by CON presented the typical Michaelis-Menten kinetics, and exhibited excellent catalytic efficiency. This study demonstrated that the CGN owns an intrinsic peroxidase-like activity.