Bimetallic MOF-derived three-dimensional nanoflowers PdCoO_x as peroxidase mimic activity for determining total...

Bimetallic MOF derivatives have shown excellent performance as nano-enzymes in the field of catalysis. Herein, PdCo oxide nanoflowers with three-dimensional flower were prepared by a simple pyrolysis method on a precursor of bimetallic PdCo-MOF. PdCoO_x showed excellent peroxidase mimic activity, which could significantly promote the oxidation of TMB by H₂O₂. Compared with CoO_x, the peroxidase mimic activity of the optimized PdCoO_x-300 increased by 2.41-fold. PdCoO_x-300 has high affinity for TMB and H₂O₂ with K_m values of 0.16 mM and 2.11 mM, which are only 57.03% and 36.87% of HRP, respectively. The highly specific peroxidase mimic activity is conducive to the sensitive detection of H₂O₂, glucose and ascorbic acid with limit of detection of 10, 100 and 10 nM, respectively. Furthermore, the total antioxidant capacity in the actual beverage samples was conducted, which showed good anti-interference ability and recovery rate.