Facile synthesis of enzyme-embedded magnetic metal–organic frameworks as a reusable mimic multi-enzyme system: mimetic peroxidase properties and colorimetric sensor

Abstract

This work reports a facile and easily-achieved approach for enzyme immobilization by embedding glucose oxidase (GOx) in magnetic zeolitic imidazolate framework 8 (mZIF-8) via a de novo approach. As a demonstration of the power of such materials, the resulting GOx embedded mZIF-8 (mZIF-8@GOx) was utilized as a colorimetric sensor for rapid detection of glucose. This method was constructed on the basis of metal-organic frameworks (MOFs), which possessed very fascinating peroxidase-like properties, and the cascade reaction for the visual detection of glucose was combined into one step through the mZIF-8@GOx based mimic multi-enzyme system. After characterization by electron microscopy, X-ray diffraction, nitrogen sorption, fourier transform infrared spectroscopy and vibrating sample magnetometry, the as-prepared mZIF-8@GOx was confirmed with the robust core-shell structure, the monodisperse nanoparticle had an average diameter of about 200 nm and displayed superparamagnetism with a saturation magnetization value of 40.5 emu g(-1), it also exhibited a large surface area of 396.10 m(2) g(-1). As a peroxidase mimic, mZIF-8 was verified to be highly stable and of low cost, and showed a strong affinity towards H2O2. Meanwhile, the mZIF-8 embedded GOx also exhibited improved activity, stability and greatly enhanced selectivity in glucose detection. Moreover, the mZIF-8@GOx had excellent recyclability with high activity (88.7% residual activity after 12 times reuse).

Fabrication of a magnetic nanoparticle embedded NH2-MIL-88B MOF hybrid for highly efficient covalent immobilization of lipase

“…20 28 All these approaches, enzymes were immobilized into MOFs by physical adsorption. The exclusive features of MOFs such as ultra-high porosity and tuneable functionality attracted great attention in various research fields.…”

Magnetic metal–organic frameworks as scaffolds for spatial co-location and positional assembly of multi-enzyme systems enabling enhanced cascade biocatalysis

“…Examples are the preparations of hydrogels, 15,22 hourglass shaped nanochannel reactor, 23 mesoporous silica nanoparticles, 18,24 formation of inorganic nanocrystal-protein complexes 25 and self-assembled crystals, 26 microbeads, 27,28 DNA nanostructures, 4,5,11,[29][30][31] polymersomes, 14,32 nanoparticles, 33 nanobers, 13,16,34 graphene, 9,35 and metal-organic frameworks (MOFs). 17,36,37 In contrast to other scaffolds, MOFs, which are formed by the self-assembly of metal ions and organic linkers, feature ultrahigh surface area and porosity, uniform pores with tunable sizes, surfaces with variable chemistries, and structural diversity. 38 The large surface area and uniform pore sizes of MOFs enhance capacity for enzyme immobilization and facilitate mass transport.…”

“…The MOF scaffold is then formed in an aqueous buffer at room temperature. 17,36,[42][43][44] Particularly, Wu et al used successfully this strategy to the preparation of a bienzyme nanosystem containing glucose oxidase (GOx) and horseradish peroxidase (HRP) encapsulated in zeolitic imidazolate framework ZIF-8. 17 At the same time, Hou et al reported a mimic GOx@mZIF-8 multienzyme system in which magnetic MOF acted as a mimetic peroxidase.…”

A Fluorescent Zirconium‐Based Metal‐Organic Framework for Selective Detection of Nitro Explosives and Metal Ions

“…[7][8][9][10] Therefore, an increasing attention is being paid to the design and synthesis of luminescent MOFs for sensitive and selective detection [11][12][13] of metal ions, [14][15][16] solvent molecules, [17,18] and nitro explosives [19][20][21][22] on the basis of fluorescence quenching process. [29,30] In this aspect, MOF-based fluorescence chemosensors have been recently demonstrated to be very promising for the detection of nitro-explosives owing to their high sensitivity and convenient visual detection, [31][32][33][34] as well as the merits of MOFs mentioned above. [29,30] In this aspect, MOF-based fluorescence chemosensors have been recently demonstrated to be very promising for the detection of nitro-explosives owing to their high sensitivity and convenient visual detection, [31][32][33][34] as well as the merits of MOFs mentioned above.…”