Enhanced Chemiluminescence Determination of Hydrogen Peroxide in Milk Sample Using Metal–Organic Framework Fe–MIL–88NH₂ as Peroxidase Mimetic

The presence of hydrogen peroxide (H₂O₂) in milk is a major concern because it constitutes a public health hazard. Here, a sensitive flow injection chemiluminescence method was established for the detection of H₂O₂. As a peroxidase mimetic, metal–organic framework Fe–MIL–88NH₂ was found to significantly enhance the chemiluminescence of luminol–H₂O₂ reaction. The enhancement mechanism could be attributed to peroxidase-like activity of Fe–MIL–88NH₂, which effectively catalyzed the decomposition of H₂O₂ into hydroxyl radical. The experimental conditions for the chemiluminescence reaction were thoroughly investigated. The chemiluminescence intensity was proportional to the concentration of H₂O₂ in the range of 0.1–10.0 μmol/L. The detection limit was 0.025 μmol/L H₂O₂, and the relative standard deviation was 2.6 % for 11 replicated measurements of 1.0 μmol/L H₂O₂ solution. The practicability of this method was demonstrated by determining H₂O₂ in milk samples.