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Cancer cells typically display redox imbalance compared with normal cells due to increased metabolic rate, accumulated mitochondrial dysfunction, elevated cell signaling, and accelerated peroxisomal activities. This redox imbalance may regulate gene expression, alter protein stability, and modulate existing cellular programs, resulting in inefficient treatment modalities. Therapeutic strategies targeting intra‐ or extracellular redox states of cancer cells at varying state of progression may trigger programmed cell death if exceeded a certain threshold, enabling therapeutic selectivity and overcoming cancer resistance to radiotherapy and chemotherapy. Nanotechnology provides new opportunities for modulating redox state in cancer cells due to their excellent designability and high reactivity. Various nanomaterials are widely researched to enhance highly reactive substances (free radicals) production, disrupt the endogenous antioxidant defense systems, or both. Here, the physiological features of redox imbalance in cancer cells are described and the challenges in modulating redox state in cancer cells are illustrated. Then, nanomaterials that regulate redox imbalance are classified and elaborated upon based on their ability to target redox regulations. Finally, the future perspectives in this field are proposed. It is hoped this review provides guidance for the design of nanomaterials‐based approaches involving modulating intra‐ or extracellular redox states for cancer therapy, especially for cancers resistant to radiotherapy or chemotherapy, etc. [ABSTRACT FROM AUTHOR]

In response to the trend of drug−resistant and super bacteria, the existing single antibacterial methods are not sufficient to kill bacteria, and the development of multifunctional antibacterial nanomaterials is urgent. Our study aims to construct copper−doped polydopamine−coated Ti3C2Tx (CuPDA@Ti3C2Tx) with an enhanced photothermal property and Fenton−like activity. The nanocomposite hydrogel consisting of CuPDA@Ti3C2Tx and alginate can improve the antioxidant activity of two−dimensional MXene nanosheets by coating them with a thin layer of PDA nanofilm. Meanwhile, Cu ions are adsorbed through the coordination of PDA−rich oxygen−containing functional groups and amino groups. Calcium ions were further used to crosslink sodium alginate to obtain antibacterial hydrogel materials with combined chemotherapy and photothermal therapy properties. The photothermal conversion efficiency of CuPDA@Ti3C2Tx is as high as 57.7% and the antibacterial rate of Escherichia coli reaches 96.12%. The photothermal effect leads to oxidative stress in bacteria, increases cell membrane permeability, and a high amount of ROS and copper ions enter the interior of the bacteria, causing protein denaturation and DNA damage, synergistically leading to bacterial death. Our study involves a multifunctional synergistic antibacterial nanodrug platform, which is conducive to the development of high−performance antibacterial agents and provides important research ideas for solving the problem of drug−resistant bacteria. [ABSTRACT FROM AUTHOR]

Fuel‐driven self‐assembly widely exists in the biological world since functional micro‐ or nanostructures in living bodies are usually transiently formed by biomolecular self‐assembly far from thermodynamic equilibrium driven by active molecules (chemical fuel), for example, adenosine triphosphate (ATP). Therefore, research focusing on artificial fuel‐driven self‐assembly has drawn extensive attention in recent years. Compared with spontaneous molecular self‐assembly at thermodynamic equilibrium, constructing a fuel‐driven self‐assembly remains complicated because it requires a delicately designed chemical reaction network mainly involving an "activation" and a "deactivation". In this Minireview, we will review recent developments in fuel‐driven self‐assembly and generalize several strategies for constructing such a self‐assembly. Besides that, the functional micro‐ or nanostructures and materials achieved by these fuel‐driven self‐assemblies will also be discussed. [ABSTRACT FROM AUTHOR]

Summary: We briefly review the basic concepts and methodologies in designing and fabricating polyoxometalate-based nanostructured thin films, and their diverse applications. [ABSTRACT FROM AUTHOR]

The peroxidase (POD)- and glucose oxidase (GOx)-like activity of Au nanoparticles (AuNPs) is very low compared to that of natural enzymes, which greatly limits their application in biological field. Herein, we found that the enlargement of AuNPs by dopamine-mediated seeded growth strategy could significantly accelerate the POD- and GOx-like activity of AuNPs. The increase of the dual enzyme-like activities may be ascribed to the formation of branched Au superstructures in the seeded growth process. With the enhancement of dual enzyme-like activities of AuNPs, a sensitive and selective colorimetric detection of dopamine and glucose can be achieved respectively. This work is expected to provide a general method to synthesize other metal-based nanomaterials with branched superstructures and extend its application in areas such as medical diagnosis and therapy. [Display omitted] • The negligible GOx- and low POD-like activity of Au nanoparticles were greatly enhanced by seeded growth strategy. • The branched superstructures was a contributing factor to the increase of dual-enzyme mimetic activities of Au nanoparticles. • A sensitive colorimetric detection of dopamine and glucose were achieved. [ABSTRACT FROM AUTHOR]

Abstract: The optical transducer of CdTe semiconductor quantum dots (QDs) has been integrated with acetylcholinesterase enzyme (AChE) by the layer-by-layer (LbL) assembly technique, resulting in a highly sensitive biosensor for detection of organophosphorus pesticides (OPs) in vegetables and fruits based on enzyme inhibition mechanism. The detection limits of the proposed biosensors are as low as 1.05×10−11 M for paraoxon and 4.47×10−12 M for parathion, which are significantly better than those of the conventional GC/MS methods or amperometric biosensors (0.5nM). These biosensors are used for quick determination of low concentrations of OPs in real vegetable and fruit samples and exhibit satisfactory reproducibility and accuracy. Moreover, the stock stability of the biosensors are very good due to the stabilizing environment for the enzyme in the nanostructures made by LbL technique. Many advantages provided by these biosensors, like fluorescent change recognized by naked eyes and mass production with low cost, will facilitate future development of rapid and high-throughput screening of OPs. [ABSTRACT FROM AUTHOR]