基于铜氧化物/氮掺杂碳纳米材料类过氧化物酶的没食子酸丙酯比色检测OA

Carbon dots were prepared via a hydrothermal method using adenine and sodium tartrate as precursors,followed by self-assembly with copper ions to form carbon dot-copper hydrogels.These hydrogels were then used as precursors to successfully synthesize copper oxide/nitrogen-doped carbon nanomaterials(CuxO/C-N)with peroxidase-like activity through calcination.The morphology and structure of the materials were characterized by scanning electron microscopy,X-ray photoelectron spectroscopy,and X-ray diffraction.In the presence of hydrogen peroxide(H2O2),CuxO/C-N catalyzed the oxidation of colorless 3,3′,5,5′-tetramethylbenzidine(TMB)to its blue oxidized form(oxTMB).Upon addition of propyl gallate(PG),the color of the system faded significantly and the absorbance decreased.Based on this phenomenon,a sensitive and accurate colorimetric sensor for PG detection was developed.The constructed sensor exhibited a linear detection range of 0.1-20 μmol/L for PG,with a limit of detection(LOD,3σ)of 0.042 μmol/L.It was revealed that the detection of PG via the CuxO/C-N-catalyzed oxidation of TMB by H2O2 involved two pathways:PG could directly reduce oxTMB,and could also scavenge reactive oxygen species(ROS)in the system,thereby reducing the oxidation of TMB by ROS,resulting in a decrease in solution color intensity.This sensor demonstrated good selectivity and was successfully applied to detection of PG in edible oils samples.