Types Of Nanozymes Research Articles

Application of Drug Delivery System Based on Nanozyme Cascade Technology in Chronic Wound.

Chronic wounds are characterized by long-term inflammation, including diabetic ulcers, traumatic ulcers, etc., which provide an optimal environment for bacterial proliferation. At present, antibiotics are the main clinical treatment method for chronic wound infections. However, the overuse of antibiotics may accelerate the emergence of drug-resistant bacteria, which poses a significant threat to human health. Therefore, there is an urgent need to develop new therapeutic strategies for bacterial infections. Nanozyme-based antimicrobial therapy (NABT) is an emerging antimicrobial strategy with broad-spectrum activity and low drug resistance compared to traditional antibiotics. NABT has shown great potential as an emerging antimicrobial strategy by catalyzing the generation of reactive oxygen species (ROS) with its enzyme-like catalytic properties, producing a powerful bactericidal effect without developing drug resistance. Nanozyme-based cascade antimicrobial technology offers a new approach to infection control, effectively improving antimicrobial efficacy by activating cascades against bacterial cell membranes and intracellular DNA while minimizing potential side effects. However, it is worth noting that this technology is still in the early stages of research. This article comprehensively reviews wound classification, current methods for the treatment of wound infection, different types of nanozymes, the application of nanozyme cascade reaction technology in antimicrobial therapy, and future challenges and prospects.

The Exploration of Nanozymes for Biosensing of Pathological States Tailored to Clinical Theranostics.

The nanozymes (NZs) are the artificial catalyst deployed for biosensing with their uniqueness (high robustness, surface tenability, inexpensive, and stability) for obtaining a better response/miniaturization of the varied sensors than their traditional ancestors. Nowadays, nanomaterials with their broadened scale such as metal-organic frameworks (MOFs), and metals/metal oxides are widely engaged in generating NZ-based biosensors (BS). Diverse strategies like fluorescent, colorimetric, surface-enhanced Raman scattering (SERS), and electrochemical sensing principles were implemented for signal transduction of NZs. Despite broad advantages, numerous encounters (like specificity, feasibility, stability, and issues in scale-up) are affecting the potentialities of NZs-based BS, and thus need prior attention for a promising exploration for a revolutionary outcome in advanced theranostics. This review includes different types of NZs, and the progress of numerous NZs tailored bio-sensing techniques in detecting abundant bio analytes for theranostic purposes. Further, the discussion highlighted some recent challenges along with their progressive way of possibly overcoming followed by commercial outbreaks.

Optimizing the standardized assays for determining the catalytic activity and kinetics of peroxidase-like nanozymes.

Nanozymes are nanomaterials with enzyme-like catalytic properties. They are attractive reagents because they do not have the same limitations of natural enzymes (e.g., high cost, low stability and difficult storage). To test, optimize and compare nanozymes, it is important to establish fundamental principles and systematic standards to fully characterize their catalytic performance. Our 2018 protocol describes how to characterize the catalytic activity and kinetics of peroxidase nanozymes, the most widely used type of nanozyme. This approach was based on Michaelis-Menten enzyme kinetics and is now updated to take into account the unique physicochemical properties of nanomaterials that determine the catalytic kinetics of nanozymes. The updated procedure describes how to determine the number of active sites as well as other physicochemical properties such as surface area, shape and size. It also outlines how to calculate the hydroxyl adsorption energy from the crystal structure using the density functional theory method. The calculations now incorporate these measurements and computations to better characterize the catalytic kinetics of peroxidase nanozymes that have different shapes, sizes and compositions. This updated protocol better describes the catalytic performance of nanozymes and benefits the development of nanozyme research since further nanozyme development requires precise control of activity by engineering the electronic, geometric structure and atomic configuration of the catalytic sites of nanozymes. The characterization of the catalytic activity of peroxidase nanozymes and the evaluation of their kinetics can be performed in 4 h. The procedure is suitable for users with expertise in nano- and materials technology.

Aspartic acid-Cu(Ⅱ)-based nanozymes for combating bacterial infections

Nanozymes based on the coordination of amino acids and metal ions exhibit pronounced peroxidase (POD)-like activity, holding promising prospects in mitigating bacterial resistance caused by antibiotic misuse and harboring tremendous potential in the treatment of bacterial infections. In this study, L-/D-aspartic acid (L-/D-Asp) were individually coordinated with copper ions using a simple self-assembly approach, culminating in the creation of L-/D-hydrogel and nanofibers (L-/D-Gel and NFs) with POD-like actiity. These materials displayed excellent inhibitory effects against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Particularly, compared to L-/D-Gel, L-/D-NFs demonstrated excellent catalytic activity at extremely low concentrations. Moreover, our prepared nanozymes exhibited higher catalytic activity over a broader range of temperature and pH levels compared to the natural enzyme horseradish peroxidase (HRP). In summary, the prepared L-/D-Gel and NFs, as a novel type of nanozyme, hold great promise for widespread applications in the treatment of bacterial infections in wounds.

Ultrasmall Cu2O@His with laccase- and catechol oxidase-like activity: Applications in phenolic drug identification and degradation

Nanozymes constitute a category of nanomaterials exhibiting the potential to replace natural enzymes. Although many types of nanozymes have been widely reported in different fields, fabricating nanozymes with ultrasmall dimensions and expanding their applications is still a great challenge. In this study, we present a cost-effective, one-step methodology for producing ultrasmall Cu2O@His. Comparative to natural laccases, Cu2O@His demonstrates remarkable catalytic capabilities in phenolic catalysis, alongside robust stability and economic viability. Therefore, some potential applications of Cu2O@His as an alternative to natural laccase were explored. Cu2O@His has been utilized not only for the detection of epinephrine but also for the degradation of tetracycline antibiotics. In addition, four kinds of TCs were successfully distinguished by principal component analysis. This work provides new ideas and methods for the development of nanozymes with ultrasmall dimensions and for the study of applications of laccase-like activity.

A Single-Atom Manganese Nanozyme Mn-N/C Promotes Anti-Tumor Immune Response via Eliciting Type I Interferon Signaling.

Tumor microenvironment (TME)-induced nanocatalytic therapy is a promising strategy for cancer treatment, but the low catalytic efficiency limits its therapeutic efficacy. Single-atom catalysts (SACs) are a new type of nanozyme with incredible catalytic efficiency. Here, a single-atom manganese (Mn)-N/C nanozyme is constructed. Mn-N/C catalyzes the conversion of cellular H2O2 to ∙OH through a Fenton-like reaction and enables the sufficient generation of reactive oxygen species (ROS), which induces immunogenic cell death (ICD) of tumor cells and significantly promotes CD8+T anti-tumor immunity. Moreover, RNA sequencing analysis reveals that Mn-N/C treatment activates type I interferon (IFN) signaling, which is critical for Mn-N/C-mediated anti-tumor immune response. Mechanistically, the release of cytosolic DNA and Mn2+ triggered by Mn-N/C collectively activates the cGAS-STING pathway, subsequently stimulating type I IFN induction. A highly efficient single-atom nanozyme, Mn-N/C, which enhances anti-tumor immune response and exhibits synergistic therapeutic effects when combined with the anti-PD-L1 blockade, is proposed.

Advances in machine learning-enhanced nanozymes.

Nanozymes, synthetic nanomaterials that mimic the catalytic functions of natural enzymes, have emerged as transformative technologies for biosensing, diagnostics, and environmental monitoring. Since their introduction, nanozymes have rapidly evolved with significant advancements in their design and applications, particularly through the integration of machine learning (ML). Machine learning (ML) has optimized nanozyme efficiency by predicting ideal size, shape, and surface chemistry, reducing experimental time and resources. This review explores the rapid advancements in nanozyme technology, highlighting the role of ML in improving performance across various bioapplications, including real-time monitoring and the development of chemiluminescent, electrochemical and colorimetric sensors. We discuss the evolution of different types of nanozymes, their catalytic mechanisms, and the impact of ML on their property optimization. Furthermore, this review addresses challenges related to data quality, scalability, and standardization, while highlighting future directions for ML-driven nanozyme development. By examining recent innovations, this review highlights the potential of combining nanozymes with ML to drive the development of next-generation diagnostic and detection technologies.

Understanding gold nanoparticles decorated on silica as oxidase mimics and application of the light-enhanced oxidase-like activity for detection of acetylcholinesterase

Composites or hybrids have received increasing interest as new types of nanozymes that not only enhance the catalytic performance but also endow new catalytic activities. In this work, the preparation of gold nanoparticles decorated on silica (SiO2-AuNPs) exhibited both peroxidase- and oxidase-like activities, which allowed investigation of the contribution of the SiO2 support involved in the oxidase-like reaction. Specific inhibitors were used to block catalytic sites on AuNPs and verify that active sites of the peroxidase- and oxidase-like activities for SiO2-AuNPs were only located on AuNPs. Impressively. the oxidase-like activity of SiO2-AuNPs could be enhanced by visible light irradiation, which involved with superoxide anion (O2•–) as the main reactive species. In addition, the reduction of silver ions (Ag+) upon irradiation of SiO2-AuNPs supported the electron transfer between SiO2 and AuNPs. A possible mechanism for the photogenerated hot electron migration of SiO2-AuNPs was proposed. The present work provides new insights into the in-depth mechanistic understanding of SiO2 as the support and the design of composites for multi-functional nanozymes.

Recent progress in nanozymes for the treatment of diabetic wounds.

The slow healing of diabetic wounds has seriously affected human health. Meanwhile, the open wounds are susceptible to bacterial infection. Clinical therapeutic methods such as antibiotic therapy, insulin treatment, and surgical debridement have made great achievements in the treatment of diabetic wounds. However, drug-resistant bacteria will develop after long-term use of antibiotics, resulting in decreased efficacy. To improve the therapeutic effect, increasing drug concentration is a common strategy in clinical practice, but it also brings serious side effects. In addition, hyperglycemia control or surgical debridement can easily bring negative effects to patients, such as hypoglycemia or damage of normal tissue. Therefore, it is essential to develop novel therapeutic strategies to effectively promote diabetic wound healing. In recent years, nanozyme-based diabetic wound therapeutic systems have received extensive attention because they possess the advantages of nanomaterials and natural enzymes. For example, nanozymes have the advantages of a small size and a high surface area to volume ratio, which can enhance the tissue penetration of nanozymes and increase the reactive active sites. Moreover, compared with natural enzymes, nanozymes have more stable catalytic activity, lower production cost, and stronger operability. In this review, we first reviewed the basic characteristics of diabetic wounds and then elaborated on the catalytic mechanism and action principle of different types of nanozymes in diabetic wounds from three aspects: controlling bacterial infection, controlling hyperglycemia, and relieving inflammation. Finally, the challenges, prospects and future implementation of nanozymes for diabetic wound healing are outlined.

Multifaceted nanozymes for synergistic antitumor therapy: A review

Although various cancer therapies have been developed in the last decade, much of their anti-tumor effects are restricted by the tumor microenvironment complexity, such as the hypoxia in photodynamic therapy and sonodynamic therapy, and the poor penetration of radiosensitizers in radiotherapy. The development of multifunctional nanozymes that combines the physiochemical properties of nanomaterials (e.g. special optical transformation properties) and catalytic activities of enzymes (mainly including superoxide dismutase, catalase, peroxidase, and oxidase) can provide promising weapons for enhancing antitumor efficiency. Importantly, some types of nanozymes can also act as ideal nanocarriers for improving therapeutic reagent delivery, especially in tumor immunotherapy. In this review, we summarize the recent advances in multifunctional nanozymes with an emphasis on their applications in catalytic therapy combined with immunotherapy, phototherapy, sonodynamic therapy, radiotherapy, and chemotherapy. We believe this review will provide theoretical and technical support for the subsequent development of nanozyme-based antitumor reagents and inspire novel therapeutic strategies for efficient tumor therapy.

Mo@ZIF-8 nanozyme preparation and its antibacterial property evaluation.

Types of nanozymes can produce free radicals and/or reactive oxygen species (ROS) to serve as broad spectrum antibacterial materials. Developing nanozyme-based antibacterial materials with good biocompatibility exhibits promising application prospects. In this study, we doped Mo to ZIF-8 (both components have good biocompatibility) to prepare a new nanozyme, Mo@ZIF-8, which can produce hydroxyl radicals (•OH) triggered by a low dosage of hydrogen peroxide (H2O2), exhibiting effective antibacterial capability against both Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus). This work provides a reference for the design of antibacterial nanozymes with good biocompatibility.

Recent Progress on the Applications of Nanozyme in Surface-Enhanced Raman Scattering

Nanozymes are nanomaterial with natural enzyme-like activity and can catalyze specific reactions for analyte identification and detection. Compared to natural enzymes, they have several benefits, including being steady, low-cost, easy to prepare and store. Based on the promising development of nanozymes in surface-enhanced Raman scattering (SERS), this paper reviews the classification of different types of nanozymes in SERS, including metal-based nanozyme, carbon-based nanozyme, metal-organic framework (MOF)/covalent organic framework (COF)-based nanozyme, and semiconductor-based nanozyme, followed by a detailed overview of their SERS applications in disease diagnosis, food safety, and environmental safety. Finally, this paper discusses the practical shortcomings of nanozymes in SERS applications and makes some suggestions for further research.

2H–MoS2/Co3O4 nanohybrid with type I nitroreductase-mimicking activity for the electrochemical assays of nitroaromatic compounds

A type I nitroreductase-mimicking nanocatalyst based on 2H–MoS2/Co3O4 nanohybrids for trace nitroaromatic compounds detection is reported in this work. For the preparation of nanocatalyst, ultrathin Co3O4 nanoflakes array was in-situ grown onto 2H–MoS2 nanosheets forming three-dimensional (3D) nanohybrid with large specific surface area as well as abundant active sites. The as-prepared nanocatalyst shows a specific affinity as well as high catalytic activity towards nitroaromatic compounds. Given the favorable nitroreductase-mimicking catalytic activity of 2H–MoS2/Co3O4 nanohybrid, a sensitive and efficient electrochemical microsensor has been constructed for the detection of 2, 4, 6-trinitrotoluene (TNT). Under optimized conditions, the microsensor displayed sensitive response from μM to pM levels with a limit of detection (LOD) of 1 pM. We further employed photoelectron spectroscopy (XPS) analysis and high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method to identify the nitroreductase-mimicking mechanism of 2H–MoS2/Co3O4 nanohybrids towards 2, 4, 6- TNT. It was found that the abundant oxygen vacancies in ultrathin Co3O4 nanoflakes played an essential role in determining its catalytic performance. Moreover, the developed MoS2/Co3O4 nanozyme has a lower Michaelis-Menten constant (km) than that of nature nitroreductase demonstrating a good enzymatic affinity towards its substrates, and further generating a high catalytic activity. This research not only proposed a new type of nanozyme, but also developed a portable electrochemical microsensor for the detection of 2, 4, 6-TNT.

Emerging nanozymes for potentiating radiotherapy and radiation protection

While radiotherapy is a mainstay therapeutic modality for malignant tumor, the intrinsic tumor resistance to radiotherapy, as well as the concomitant radiation injury to adjacent healthy tissues, greatly limits the efficacy of cancer radiotherapy. As a result, the development of novel radioenhancers and radioprotectants is highly desired for clinical radiotherapy. In recent years, nanozymes have inspired ever-growing research interest because of their multi-enzyme activities and microenvironment-responsive feature. In view of the significant progress of nanozymes in radiation medicine, we, in this review, systematically illustrate the impressive progress of nanozymes for potentiating radiotherapy and radiation protection. First, the types of nanozymes used in tumor radiotherapy are briefly discussed. Subsequently, the main strategies of nanozymes to enhance the radiotherapy efficiency, including promoting the generation of reactive oxygen species (ROS), relieving hypoxia in tumor microenvironment and combining with other cancer therapeutic regimens, are summarized. Finally, the advances of typical nanozymes for preventing radiation-induced hematopoietic damage and gastrointestinal damage are highlighted.

Progress and Perspective on Carbon-Based Nanozymes for Peroxidase-like Applications.

Tumor microenvironment-responsive chemodynamic therapy (CDT), an approach based on Fenton/Fenton-like reaction to convert hydrogen peroxide (H2O2) into the highly cytotoxic hydroxyl radical (·OH) in situ to kill cancer cells, represents an important direction for cancer therapy. Different types of nanozymes (nanomaterial-based catalysts that can mimic the activities of natural enzymes) have been developed to mimic peroxidase. This Perspective highlights the latest research progress regarding low-cost and biocompatible carbon-based nanozymes for peroxidase mimics. The effects of structure and surface properties of carbon-based nanozymes on their electronic transfer and peroxidase-like activity are analyzed, including nanospheres, nanotubes, nanosheets, and graphene quantum dots (GQDs) with or without surface functionalization and heteroatom doping. We expand our newly developed carbon nitride (g-C3N4) QD systems to nanozyme application, which are highly efficient in converting the intracellular H2O2 to ·OH species to kill 4T1 cancer cells and demonstrate a great potential for CDT.

The Detection of Hydrogen Peroxide by MOF-Based Nanoparticles with Micro Morphology Analysis by Transmission Electron Microscope

MOF materials are new types of nanozymes with catalytic activities. Herein, a nanozyme with peroxidase-like activities was synthesized and took on a cube-like morphology. Besides, the best environment and the detection limit of the nanozyme for hydrogen peroxide were also achieved through experiments.

Burgeoning single atoms as new types of nanozymes and electrocatalysts for sensing, biomedicine and energy conversion

Single atom catalysts (SACs), featured by atomically-level distributed active sites on supports, provide an ideal platform in the fields of energy conversion, and mimic metalloprotease for bridging the gap between natural enzymes and single atom nanozymes by virtue of their maximum atom utilization efficiency, superior selectivity and outstanding catalytic performance. In this review, the recent progress in this field is reported from the perspectives of synthesis routes, which is also a prerequisite for catalytic investigation. Subsequently, we depict their applications in different sensing systems including electrochemical, colorimetric and photoactive sensing, as well as biomedicine such as disease therapy, antibacterial and cytoprotection to demonstrate their nanoenzymatic activity, and their promising applications in electrocatalysis such as water splitting, oxygen and CO2 reduction reaction are highlighted in more details. Finally, the current challenges and future outlooks of higher loading, more activity and stable in SACs are presented.

An Ultra-Stable, Oxygen-Supply Nanoprobe Emitting in Near-Infrared-II Window to Guide and Enhance Radiotherapy by Promoting Anti-Tumor Immunity.

Currently, radiotherapy (RT) is the main method for cancer treatment. However, the hypoxic environment of solid tumors is likely to cause resistance or failure of RT. Moreover, high-dose radiation may cause side effects to surrounding normal tissues. In this study, a new type of nanozyme is developed by doping Mn (II) ions into Ag2 Se quantum dots (QDs) emitting in the second near-infrared window (NIR-II, 1000-1700nm). Through the catalysis of Mn (II) ions, the nanozymes can trigger the rapid decomposition of H2 O2 and produce O2 . Conjugated with tumor-targeting arginine-glycine-aspartate (RGD) tripeptides and polyethylene glycol (PEG) molecules, the nanozymes are then constructed into in vivo nanoprobes for NIR-II imaging-guided RT of tumors. Owing to the radiosensitive activity of the element Ag, the nanoprobes can promote radiation energy deposition. The specific tumor-targeting and NIR-II emitting abilities of the nanoprobes facilitate the precise tumor localization, which enables precise RT with low side effects. Moreover, their ultra-stability in the living body ensures that the nanoprobes continuously produce oxygen and relieve the hypoxia of tumors to enhance RT efficacy. Guided by real-time and high-clarity imaging, the nanoprobe-mediated RT promotes anti-tumor immunity, which significantly inhibits the growth of tumors or even cures them completely.

Stimuli‐Responsive Manganese Single‐Atom Nanozyme for Tumor Therapy via Integrated Cascade Reactions

AbstractThe single‐atom enzyme (SAE) is a novel type of nanozyme that exhibits extraordinary catalytic activity. Here, we constructed a PEGylated manganese‐based SAE (Mn/PSAE) by coordination of single‐atom manganese to nitrogen atoms in hollow zeolitic imidazolate frameworks. Mn/PSAE catalyzes the conversion of cellular H2O2to.OH through a Fenton‐like reaction; it also promotes the decomposition of H2O2to O2and continuously catalyzes the conversion of O2to cytotoxic.O2−via oxidase‐like activity. The catalytic activity of Mn/PSAE is more pronounced in the weak acidic tumor environment; therefore, these cascade reactions enable the sufficient generation of reactive oxygen species (ROS) and effectively kill tumor cells. The prominent photothermal conversion property of the amorphous carbon can be utilized for photothermal therapy. Hence, Mn/PSAE exhibits significant therapeutic efficacy through tumor microenvironment stimulated generation of multiple ROS and photothermal activity.

Stimuli-Responsive Manganese Single-Atom Nanozyme for Tumor Therapy via Integrated Cascade Reactions.

The single-atom enzyme (SAE) is a novel type of nanozyme that exhibits extraordinary catalytic activity. Here, we constructed a PEGylated manganese-based SAE (Mn/PSAE) by coordination of single-atom manganese to nitrogen atoms in hollow zeolitic imidazolate frameworks. Mn/PSAE catalyzes the conversion of cellular H2 O2 to . OH through a Fenton-like reaction; it also promotes the decomposition of H2 O2 to O2 and continuously catalyzes the conversion of O2 to cytotoxic . O2- via oxidase-like activity. The catalytic activity of Mn/PSAE is more pronounced in the weak acidic tumor environment; therefore, these cascade reactions enable the sufficient generation of reactive oxygen species (ROS) and effectively kill tumor cells. The prominent photothermal conversion property of the amorphous carbon can be utilized for photothermal therapy. Hence, Mn/PSAE exhibits significant therapeutic efficacy through tumor microenvironment stimulated generation of multiple ROS and photothermal activity.