Enzymatic Cascade Reactions Mediated by Highly Efficient Biomimetic Quasi Metal–Organic Frameworks

Abstract

The integration of chemo- and enzymatic catalysis for effective multistep cascades has presented critical challenges for decades. In this work, the biomimetic quasi NH2-MIL-101 (qNM) with highly efficient peroxidase-like activity was synthesized via a palmitic acid-induced strategy followed by pyrolysis. The effects of the amount of palmitic acid and calcination temperature on the synthesis of qNM were optimized. It was found that qNM was an excellent catalyst for oxidations of various peroxidase substrates, and a possible mechanism was proposed, i.e., the presence of FeII species in qNM was responsible for its excellent activity, which facilitated the transition between FeII and FeIII species to produce more hydroxyl radicals by H2O2 decomposition. The qNM served as the potential matrix for enzyme immobilization through a cross-linking method, and kinetic studies revealed that the catalytic efficiency (kcat /Km ) for the immobilized GOx (23.7 mM–1 s–1) is comparable to that of free GOx (26.9 mM–1 s–1). The immobilized GOx also showed improved stability against high temperatures and organic solvents compared to free GOx, and analysis of the secondary structure of GOx indicated that the improved stability resulted from enzyme rigidity by the intense covalent linkage with qNM. Furthermore, qNM contributed its biomimetic activity to cooperate with a single enzyme (GOx) or two enzymes (β-Gal and GOx) for the enzymatic cascade reactions. Compared with the mixture of each component in the solution, the combination of the single-enzyme system (GOx) or the two-enzyme system (β-Gal and GOx) in qNM achieved 2.67-fold and 1.83-fold enhancements in the activity of catalytic cascades, respectively. This study provides new insights into the construction of effective and synergistic cascade reactions by integrating biomimetic MOF with natural enzyme, which holds potential for applications in biotechnology and ecofriendly and biomimetic catalysis.

Fabrication of 3D Amino-Functionalized Metal–Organic Framework on Porous Nickel Foam Skeleton to Combinate Follicle Stimulating Hormone Antibody for Specific Recognition of Follicle-Stimulating Hormone

“…Iron-based MOFs or derived materials exhibit excellent sensing performances because of their potential redox ability and stability when used as electrode materials. , Construction of electrode materials with a microstructure and uniform morphology is an effectual strategy to strengthen their electrochemical characteristics . The nickel/nickel-based electrodes find great applications in electrochemical devices, supercapacitors, and fuel cells as electrode materials.…”

Advances in Visual Immunoassays for Sensitive Detection of Mycotoxins in Food—A Review

“…Nowadays, various nanozymes have been served as catalytic labels for multi-category signal amplification in newly developed immunoassays. Numerous studies revealed that metal NPs (Au, Ag, Pt, Pd) [85,86], metal oxide NPs (Fe 3 O 4 , CeO 2 , MnO 2 , CuO) [87][88][89][90][91][92], carbon-based (graphene oxide, carbon nitride, carbon dots) [93][94][95][96], and MOFs-based nanomaterials [97][98][99] with peroxidase-, catalase-, oxidase-, superoxide dismutase-mimicking properties.…”

Polyoxometalate-Based Metal–Organic Frameworks as the Solid Support to Immobilize MP-11 Enzyme for Enhancing Thermal and Recyclable Stability

“…MOFs have been applied as the attractive solid supports for enzymes not only for their being inert hosts but also to enhance the stability or activity of the enzymes. A series of reported for immobilizing enzymes in MOF have been published. − MOFs could increase the resiliency of enzymes. − For example, immobilization enzyme in the MOF support could prevent its unfolding and losing reaction activity when it is exposed to the bad reaction conditions, for example, high temperature. , …”