Abstract
In recent years, the development of artificial nanostructured enzymes has received enormous interest in nanobiotechnology due to their advantages over natural enzymes. In the present work, different amounts ( 5, 10, and 20 wt%) of Co3O4 nanoparticle decorated CeO2 hybrid flower-like microspheres ( Co3O4@CeO2) have been investigated for peroxidase-like activity and it was found that 10 wt% of Co3O4@CeO2 exhibited excellent peroxidase-like activity for the catalytic oxidation of the 3,30,5,50- tetramethylbenzidine (TMB) substrate in the presence of H2O2. The formation of more Ce3+ ions associated with the oxygen vacancies and a strong synergistic interaction between CeO2 and Co3O4 may be responsible for the enhanced peroxidase-like activity. Based on their peroxidase activity, Co3O4@CeO2 hybrid microspheres were used for the colourimetric detection of glucose. It was found that Co3O4@CeO2 hybrid microspheres showed a substantial enhancement in the detection selectivity. The limit of detection (LOD) was also improved with a limit as low as 1.9 mu M. Thus, we believe that Co3O4@CeO2 hybrid flower-like microspheres with high peroxidase-like activity can be exploited for biosensing applications.