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.

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“…74-0566). [2][3][4][14][15][16][17] The chargetransfer complexes formed from the one-electron oxidation of TMB by COH could produce two intense characteristica bsorption peaks at 370 and 658 nm. The XRD patterns of HAPNWs and HAP@MIL-100(Fe) NFs with aw ider 2q angle range are shown in FigureS1o ft he Supporting Information.…”

“…To test the peroxidase-like activity of the HAP@MIL-100(Fe) NFs, we investigatedt he catalytic oxidation of peroxidase substrate 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of [2][3][4][14][15][16][17] The chargetransfer complexes formed from the one-electron oxidation of TMB by COH could produce two intense characteristica bsorption peaks at 370 and 658 nm. [35] The absorbance at 658 nm was monitored to evaluate the optimal catalytic reactionc onditions.…”

“…Therefore, artificial enzyme mimetics, owing to their high stability,l ow cost, and ease of preparation, have attracted much interest. In particular,b ecause of their tunable structures and chemical compositions, and superior properties, nanostructured material-based enzyme mimetics, including Fe 3 O 4 nanoparticles, [2][3][4] ZnFe 2 O 4 nanoparticles, [5] CeO 2 nanoparticles, [6] Au@Pt nanoparticles, [7] Fe-Co alloy nanoparticles, [8] Co 3 O 4 nanoparticles, [1] V 2 O 5 nanowires, [9] carbon nanodots, [10] carbon nanotubes, [11,12] graphene oxide, [13] and metal-organic frameworks (MOFs), [14][15][16][17] have been investigated extensively.A mongt hese, mostp apers focusedo np owdered nanostructured materials, but nanoscale powders are difficult to recover forr euse. [9] It is expectedt hat flexible test papers will have advantages such as simplicity,l ow cost, easy storage and transportation,a nd excellent recyclability.M artinez et al have summarized the advantageso fp aper-basedd iagnostic devices, [18] for instance:1 )paper is thin and lightweight and thus easy to stack, store, transport andu se;2 )paper made primarily of plant cellulose fibers has good compatibility with biological samples.…”

Nano-Engineered Biomimetic Optical Sensors for Glucose Monitoring in Diabetes

“…Metal-organic frameworks (MOFs) and MOFs loaded with other catalysts have been reported to exhibit enzyme-like properties [56,57,58,59]. Liu et al reported a nanosized porous metal–organic framework, Fe-MIL-88NH 2 exhibiting intrinsic peroxidase-like activity and used it for colorimetric detection of glucose [59]. Qin et al demonstrated a hemin@metal-organic framework mimicking peroxidase and applied it for glucose detection.…”

“…Prussian Blue, [Fe(III)Fe(II)(CN) 6 ] − , has been also explored to mimic peroxidases. In their earlier study Gu et al showed that a Prussian Blue coating could tune the peroxidase-mimicking activity of γ-Fe 2 O 3 nanoparticles, but later they also found enzyme-like activities of Prussian Blue nanoparticles [58,59]. They also demonstrated that the enzyme-mimicking properties of Prussian Blue nanoparticles were dependent on the microenvironment.…”