Bioinspired Dual Hemin-Bonded G-Quadruplex and Histidine-Functionalized Metal-Organic Framework for Sensitive Biosensing.

Biomimetic enzymes have emerged as ideal alternatives to natural enzymes, and there is considerable interest in designing biomimetic enzymes with enhanced catalytic performance to address the low activity of the current biomimetic enzymes. In this study, we proposed a meaningful strategy for constructing an efficient peroxidase-mimicking catalyst, called HhG-MOF, by anchoring histidine (H) and dual hemin-G-quadruplex DNAzyme (double hemin covalently linked to 3' and 5' terminals of G-quadruplex DNA, short as hG) to a mesoporous metal-organic framework (MOF). This design aims to mimic the microenvironment of natural peroxidase.

A Cost-Effective Hemin-Based Artificial Enzyme Allows for Practical Applications.

Nanomaterials excel in mimicking the structure and function of natural enzymes while being far more interesting in terms of structural stability, functional versatility, recyclability, and large-scale preparation. Herein, the story assembles hemin, histidine analogs, and G-quadruplex DNA in a catalytically competent supramolecular assembly referred to as assembly-activated hemin enzyme (AA-heminzyme). The catalytic properties of AA-heminzyme are investigated both in silico (by molecular docking and quantum chemical calculations) and in vitro (notably through a systematic comparison with its natural counterpart horseradish peroxidase, HRP).

A Versatile G-Quadruplex (G4)-Coated Upconverted Metal-Organic Framework for Hypoxic Tumor Therapy.

Given the complexity of the tumor microenvironment, multiple strategies are being explored to tackle hypoxic tumors. The most efficient strategies combine several therapeutic modalities and typically requires the development of multifunctional nanocomposites through sophisticated synthetic procedures. Herein, the G-quadruplex (G4)-forming sequence AS1411-A (d[(G T) TG(TG ) A]) is used for both its anti-tumor and biocatalytic properties when combined with hemin, increasing the production of O ca.

LnNP@ZIF8 Smart System for In Situ NIR-II Ratiometric Imaging-Based Tumor Drug Resistance Evaluation.

Just-in-time evaluation of drug resistance in situ will greatly facilitate the achievement of precision cancer therapy. The rapid elevation of reactive oxygen species (ROS) is the key to chemotherapy. Hence, suppressed ROS production is an important marker for chemotherapy drug resistance.

A Double Hemin Bonded G-Quadruplex Embedded in Metal-Organic Frameworks for Biomimetic Cascade Reaction.

Biocatalytic transformations in living cells, such as enzymatic cascades, function effectively in spatially confined microenvironments. However, mimicking enzyme catalytic cascade processes is challenging. Herein, we report a new dual-Hemin-G-quadruplex (dHemin-G4) DNAzyme with high catalytic activity over noncovalent G4/Hemin and monocovalent counterparts (G4-Hemin and Hemin-G4) by covalently linking hemin to both ends of an intramolecular G4.

Efficient Biocatalytic System for Biosensing by Combining Metal-Organic Framework (MOF)-Based Nanozymes and G-Quadruplex (G4)-DNAzymes.

A high catalytic efficiency associated with a robust chemical structure are among the ultimate goals when developing new biocatalytic systems for biosensing applications. To get ever closer to these goals, we report here on a combination of metal-organic framework (MOF)-based nanozymes and a G-quadruplex (G4)-based catalytic system known as G4-DNAzyme. This approach aims at combining the advantages of both partners (chiefly, the robustness of the former and the modularity of the latter).

Engineering FeCo alloy@N-doped carbon layers by directly pyrolyzing Prussian blue analogue: new peroxidase mimetic for chemiluminescence glucose biosensing.

Herein, we report the synthesis of FeCo alloy@N-doped carbon layers (FeCo@NC), a new peroxidase mimetic, by directly pyrolyzing the FeIII-Co Prussian blue analogue (FeIII-Co PBA). The FeCo@NC composite showed excellent peroxidase-like activity due to its highly active FeCo alloy, M-N species (Co-N and Fe-N) and N-doped carbon layers with hierarchical pore nanostructures, which were formed via simple heat treatment of FeIII-Co PBA without additional C and N sources. In particular, the obtained FeCo@NC hybrid presented high CL activity with more than 85-fold enhancement in the CL emission of the H2O2-luminol system, and long-term stability compared with FeCo alloy nanoparticles.

β-Cyclodextrin functionalization of metal-organic framework MOF-235 with excellent chemiluminescence activity for sensitive glucose biosensing.

Herein, we developed a new CL method for the detection of glucose, exhibiting high sensitivity, low limit of detection, good stability and reliability for analysis of real biological samples. The MOF-235/β-cyclodextrin (β-CD) hybrids were facilely prepared by a simple method, and characterized by XRD, TGA, FT-IR and SEM. The as-prepared hybrids exhibited highly catalytic activity for the hydrogen peroxide-luminol system, and gave more than 30-fold enhancement in CL response as compared with that of hydrogen peroxide-luminol system, thus could be used for sensitive detection of HO and glucose.