Mesoporous MnFe 2 O 4 magnetic nanoparticles as a peroxidase mimic for the colorimetric detection of urine glucose.

Mesoporous MnFe 2 O 4 magnetic nanoparticles (mMnFe 2 O 4 MNPs) were prepared with a one-step synthesis method and characterized to possess intrinsic peroxidase-like activity, and had obvious advantages over other peroxidase nanozymes in terms of high catalytic affinity, high stability, mono-dispersion, easy preparation, and quick separation. The mMnFe 2 O 4 MNPs were used as a colorimetric sensor for indirect sensing of urine glucose based on the sensing principle that H 2 O 2 can be produced from glucose oxidation catalyzed by glucose oxidase (GOx), and under the catalysis of the mMnFe 2 O 4 MNPs nanozyme, H 2 O 2 can oxidize 3,3',5,5'-tetramethylbenzidine (TMB) to produce a blue color in a few minutes. This sensor is simple, cheap, sensitive, and specific to glucose detection with a detection limit of 0.7 μM, suggesting its potential for on-site glucose detection.