title: A nanosized metal-organic framework of Fe-MIL-88NH₂ as a novel peroxidase mimic used for colorimetric detection of glucose.
abstract: In this paper, a nanosized porous metal-organic framework, Fe-MIL-88NH₂, was facilely prepared with a uniform octahedral shape by the addition of acetic acid, and for the first time was demonstrated to possess intrinsic peroxidase-like activity. Kinetic analysis and electron spin resonance measurements indicated that the catalytic behavior was consistent with typical Michaelis-Menten kinetics and follows a ping-pong mechanism. As a novel peroxidase mimic material, Fe-MIL-88NH₂ shows the advantages of high catalytic efficiency, ultrahigh stability and high biocompatibility in aqueous medium compared with natural enzymes and other peroxidase nanomimetics. Here, Fe-MIL-88NH₂ was used to quickly catalyze oxidation of the peroxidase substrate 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H₂O₂ to produce a colored product, which provided a simple, sensitive and selective method for the colorimetric detection of glucose. Glucose could be linearly detected in the range from 2.0 × 10⁻⁶ to 3.0 × 10⁻⁴ M with a detection limit of 4.8 × 10⁻⁷ M, and the color variation for glucose response was also obvious by visual observation at concentrations as low as 2.0 × 10⁻⁶ M. More importantly, the colorimetric method could be successfully applied to the determination of glucose in diluted serum samples.
authors.affiliation: Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China. liyf@swu.edu.cn.
authors.forename: Ya Li
authors.initials: YL
authors.lastname: Liu
authors.forename: Xi Juan
authors.initials: XJ
authors.lastname: Zhao
authors.forename: Xiao Xi
authors.initials: XX
authors.lastname: Yang
authors.forename: Yuan Fang
authors.initials: YF
authors.lastname: Li
mesh_terms: D003124:Colorimetry / Q000379:methods; D005947:Glucose / Q000032:analysis*; D006801:Humans; D007501:Iron / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D009195:Peroxidase / Q000737:chemistry*; D014961:X-Ray Diffraction / Q000379:methods
chemical_list: D007501:Iron; D009195:Peroxidase; D005947:Glucose