Ultrasensitive Electrochemical Detection of Butylated Hydroxy Anisole via Metalloporphyrin Covalent Organic Frameworks Possessing Variable Catalytic Active Sites.

Three novel two-dimensional metalloporphyrin COFs (MPor-COF-366, M = Fe, Mn, Cu) were fabricated by changing the metal atoms in the center of the porphyrin framework. The physicochemical characteristics of MPor-COF-366 (M = Fe, Mn, Cu) composites were fully analyzed by diverse electron microscopy and spectroscopy. Under optimal conditions, experiments on determining butylated hydroxy anisole (BHA) at FePor-COF-366/GCE were conducted using differential pulse voltammetry (DPV). It is noted that the FePor-COF-366/GCE sensor showed excellent electrocatalytic performance in the electrochemical detection of BHA, compared with MnPor-COF-366/GCE and CuPor-COF-366/GCE. A linear relationship was obtained for 0.04-1000 µM concentration of BHA, with a low detection limit of 0.015 µM. Additionally, the designed sensor was successfully employed to detect BHA in practical samples, expanding the development of COF-based composites in electrochemical applications.