Metal-Phenolic Networks derived CN-FeC hollow nanozyme with robust peroxidase-like activity for total antioxidant capacity detection

A tannate-iron network-derived peroxidase-like catalyst loaded with Fe ions on carbon nitride (C 3 N 4 ) was reported for detection of total antioxidant capacity (TAC) in food in this study. Metal-phenolic networks (MPNs) was employed to form a low coordination compound on C 3 N 4 , and calcined catalyst formed hollow structure with abundant and uniform Fe sites and surface folds. CN-FeC exhibited significant peroxidase-like activity and high substrate affinity. The homogeneous distribution of amorphous Fe elements on the C 3 N 4 substrate provides more active sites, resulting in provided excellent catalytic activity to activate H 2 O 2 to 1 O 2 and O 2 ·– . The established CN-FeC/TMB/H 2 O 2 colorimetric system can detect AA in the concentration range of 5-40   μM, with the detection limits of 1.40   μM, respectively. It has good accuracy for the detection of vitamin C tablets, beverages. Taken together, this work shows that metal-phenolic networks can be an effective way to achieve efficient utilization of metal atoms and provides a promising idea for metal-phenolic networks in nanoparticle enzyme performance enhancement.