Bimetallic MOF-derived three-dimensional nanoflowers PdCoOx as peroxidase mimic activity for determining total antioxidant capacity

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 H 2 O 2 . 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 H 2 O 2 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 H 2 O 2 , 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.