Hemin@metal–organic framework with peroxidase-like activity and its application to glucose detection

Abstract

A composite material has been successfully prepared for the first time using an amino-containing metal–organic framework (MOF) as a new type of host matrix material to anchor hemin and simulate the peptidic microenvironment of the native peroxidase. The material was characterized by XRD, SEM, EDS, FT-IR techniques and an N₂ adsorption method. It exhibited peroxidase-like activity through catalytic oxidation of the peroxidase substrate 3,3,5,5-tetramethylbenzidine (TMB) in the presence of H₂O₂, producing a blue-colored solution. Under optimal conditions, the absorbance at 652 nm is linearly correlated with the concentration of H₂O₂ from 5.0 × 10⁻⁶ mol L⁻¹ to 2.0 × 10⁻⁴ mol L⁻¹ (R² = 0.994). More importantly, a sensitive and selective method for glucose detection was developed using the as-prepared mimetic peroxidase as a catalyst with the help of glucose oxidase (GOx). The analytical platform for glucose detection was observed to have a linear range from 1.0 × 10⁻⁵ mol L⁻¹ to 3.0 × 10⁻⁴ mol L⁻¹ (R² = 0.993). This work informs researchers of the advantages of MOFs for preparing biomimetic catalysts and extends the functionality of MOFs to biosensor applications.