Innovative Colorimetric NQO1 Detection Strategy via Substrate Competitive and Biomimetic Cascade Reactions with a Highly Active NADH Oxidase Mimic.

NAD(P)H: quinone oxidoreductase-1 (NQO1) plays critical roles in antioxidation and abnormally overexpresses in tumors. Developing a fast and sensitive method of monitoring NQO1 will greatly promote cancer diagnosis in clinical practice. This study introduces a transformative colorimetric detection strategy for NQO1, harnessing an innovative competitive substrate mechanism between NQO1 and a new NADH oxidase (NOX) mimic, cobalt-nitrogen-doped carbon nanozyme (CoNC). This method ingeniously exploits the differential consumption of NADH in the presence of NQO1 to modulate the generation of H2O2 from CoNC catalysis, which is then quantified through a secondary, peroxidase-mimetic cascade reaction involving Prussian blue (PB) nanoparticles. This dual-stage reaction framework not only enhances the sensitivity of NQO1 detection, achieving a limit of detection as low as 0.67 µg mL-1, but also enables the differentiation between cancerous and noncancerous cells by their enzymatic activity profiles. Moreover, CoNC exhibits exceptional catalytic efficiency, with a specific activity reaching 5.2 U mg-1, significantly outperforming existing NOX mimics. Beyond mere detection, CoNC serves a dual role, acting as both a robust mimic of cytochrome c reductase (Cyt c) and a cornerstone for enzymatic regeneration, thereby broadening the scope of its biological applications. This study not only marks a significant step forward in the bioanalytical application of nanozymes but also sets the stage for their expanded use in clinical diagnostics and therapeutic monitoring.

Electrochemical microfluidic sensing platforms for biosecurity analysis.

Biosecurity encompasses the health and safety of humans, animals, plants, and the environment. In this article, "biosecurity" is defined as encompassing the comprehensive aspects of human, animal, plant, and environmental safety. Reliable biosecurity testing technology is the key point for effectively assessing biosecurity risks and ensuring biosecurity. Therefore, it is crucial to develop excellent detection technologies to detect risk factors that can affect biosecurity. An electrochemical microfluidic biosensing platform integrates fluid control, target recognition, signal transduction, and output and incorporates the advantages of electrochemical analysis technology and microfluidic technology. Thus, an electrochemical microfluidic biosensing platform, characterized by exceptional analytical sensitivity, portability, rapid analysis speed, low reagent consumption, and low risk of contamination, shows considerable promise for biosecurity detection compared to traditional, more complex, and time-consuming detection technologies. This review provides a concise introduction to electrochemical microfluidic biosensors and biosecurity. It highlights recent research advances in utilizing electrochemical microfluidic biosensing platforms to assess biosecurity risk factors. It includes the use of electrochemical microfluidic biosensors for the detection of risk factors directly endangering biosecurity (direct application: namely, risk factors directly endangering the health of human, animals, and plants) and for the detection of risk factors indirectly endangering biosecurity (indirect application: namely, risk factors endangering the safety of food and the environment). Finally, we outline the current challenges and future perspectives of electrochemical microfluidic biosensing platforms.

Value of endoscopic grading of gastroesophageal flap valve in gastroesophageal reflux disease.

OBJECTIVE: To investigate the significance of endoscopic grading (Hill's classification) of gastroesophageal flap valve (GEFV) in the examination of patients with gastroesophageal reflux disease (GERD). METHODS: One hundred and sixty-two patients undergoing gastroscopy in the Department of Gastroenterology, Xingyi People's Hospital between Apr. 2022 and Sept. 2022 were selected by convenient sampling, and data such as GEFV grade, and findings of esophageal high-resolution manometry (HRM) and esophageal 24-h pH/impedance reflux monitoring, and Los Angeles (LA) classification of reflux esophagitis (RE) were collected and compared. RESULTS: Statistically significant differences in age (F = 9.711, P < 0.001) and hiatal hernia (χ = 35.729, P < 0.001) were observed in patients with different GEFV grades. The resting LES pressures were 12.12 ± 2.79, 10.73 ± 2.68, 9.70 ± 2.29, and 8.20 ± 2.77 mmHg (F = 4.571, P < 0.001) and LES lengths were 3.30 ± 0.70, 3.16 ± 0.68, 2.35 ± 0.83, and 2.45 ± 0.62 (F = 3.789, P = 0.011), respectively, in patients with GEFV grades I-IV. DeMeester score (Z = 5.452, P < 0.001), AET4 (Z = 5.614, P < 0.001), acid reflux score (upright) (Z = 7.452, P < 0.001), weak acid reflux score (upright) (Z = 3.121, P = 0.038), liquid reflux score (upright) (Z = 3.321, P = 0.031), acid reflux score (supine) (Z = 6.462, P < 0.001), mixed reflux score (supine) (Z = 3.324, P = 0.031), gas reflux score (supine) (Z = 3.521, P = 0.024) were different in patients with different GEFV grades, with statistically significant differences. Pearson correlation analysis revealed a positive correlation between RE grade and LA classification of GERD (r = 0.662, P < 0.001), and the severity of RE increased gradually with the increase of the Hill grades of GEFV. CONCLUSION: The Hill grade of GEFV is related to age, hiatal hernia, LES pressure, and the consequent development and severity of acid reflux and RE. Evaluation of esophageal motility and reflux based on the Hill grade of GEFV is of significance for the diagnosis and treatment of GERD.

Integrated Cascade Nanozymes with Antisenescence Activities for Atherosclerosis Therapy.

Senescent cells are the critical drivers of atherosclerosis formation and maturation. Mitigating senescent cells holds promise for the treatment of atherosclerosis. In an atherosclerotic plaque microenvironment, senescent cells interact with reactive oxygen species (ROS), promoting the disease development. Here, we hypothesize that a cascade nanozyme with antisenescence and antioxidant activities can serve as an effective therapeutic for atherosclerosis. An integrated cascade nanozyme with superoxide dismutase- and glutathione peroxidase-like activities, named MSe1 , is developed in this work. The obtained cascade nanozyme can attenuate human umbilical vein endothelial cell (HUVEC) senescence by protecting DNA from damage. It significantly weakens inflammation in macrophages and HUVECs by eliminating overproduced intracellular ROS. Additionally, the MSe1 nanozyme effectively inhibits foam cell formation in macrophages and HUVECs by decreasing the internalization of oxidized low-density lipoprotein. After intravenous administration, the MSe1 nanozyme significantly inhibits the formation of atherosclerosis in apolipoprotein E-deficient (ApoE-/- ) mice by reducing oxidative stress and inflammation and then decreases the infiltration of inflammatory cells and senescent cells in atherosclerotic plaques. This study not only provides a cascade nanozyme but also suggests that the combination of antisenescence and antioxidative stress holds considerable promise for treating atherosclerosis.

Porphyrin-Containing Metallacage with Precise Active Sites and Super Long-Term Stability as a Specific Peroxidase Mimic for Versatile Analyte Determination.

Inspired by the architecture of single-atom catalysts, where the monodispersed metal atoms are widely distributed but stabilized by various coordination circumstances, the biomimetic design and synthesis of metalloporphyrin-containing nanocages have been demonstrated in this study. The nanocages were fabricated through a coordination-driven self-assembly process, and the Mn(III) porphyrin-based one was found to have exclusively peroxidase-like activity at pH 6.0 with neither oxidase nor catalase-like activity under the routine conditions. Benefiting from this, we demonstrated the wide applicability and convenient usage of an Mn(III)-containing supramolecular nanocage (Mn-PC) in the one-step detection of H2O2, sarcosine, and glucose through various oxidase-involved reactions, with a satisfactory detection limit and eligible specificity. Real samples including H2O2 in lens care solution, sarcosine in human urine, and glucose in human serum were also assayed, showing an adequate recovery rate. Such a specific activity originates from the super-consistent microstructure of each catalytic unit, which means that the active site of manganese porphyrin was "protected" by the confinement of the nanocage. This also helps to sustain the super long-term activity even after 545 days of storage. Furthermore, the intrinsic electronic structure of the Mn(III)-containing supramolecular nanocage endows the ability in electrochemical detection of H2O2 and glucose. Our smart design toward the supramolecular nanocages with a defined structure and quantity contributes to the construction of the ingenious sensing platform and has guiding significance for architectural design of nanozymes.

A Dopamine-Enabled Universal Assay for Catalase and Catalase-Like Nanozymes.

Developing a universal strategy to measure catalase (CAT)/CAT-like activity, on one hand, overcomes limitations on current assays, such as moderate sensitivity and limited sample scope; on the other hand, facilitates insightful studies on applications of CAT and CAT-like nanozymes. Herein, the oxygen-sensitive and H2O2-inhibitory self-polymerization of dopamine (DA) was demonstrated as an activity indicator of CAT or CAT-like nanozymes, which monitors the catalytically generated O2 in a hypoxic environment. A typical assay for natural CAT was achieved under the optimized conditions. Moreover, this assay was suitable for diverse types of samples, ranging from nanozymes, animal tissues, to human saliva. By comparing the merits and limitations of common methods, this assay shows all-round advantages in sensitivity, specificity, and versatility, facilitating the formulation of measurement criteria and the development of potential standardized assays for CAT (or CAT-like nanozyme) activity.

Recent Advances in Stability Issues of Inorganic Solid Electrolytes and Composite Solid Electrolytes for All-Solid-State Batteries.

The development of solid-state batteries has become one of the most promising directions in rechargeable secondary batteries due to their considerable energy densities and favorable safety. However, solid-state batteries with higher energy density and more durable and stable cycle life should be developed for large-scale energy storage and adaption to the rapidly increasing lithium battery production and sales market. Although inorganic solid electrolytes (ISEs) and composite solid electrolytes (CSEs) are relatively advantageous solid-state electrolytes, they also face severe challenges. This review summarizes the main stability issues related to chemical, mechanical, thermal, and electrochemical aspects faced by ISEs and CSEs. The corresponding state-of-the-art improvement strategies have been proposed, including filling of modified particles, electrolyte pore adjustment, electrolyte internal structure arrangement, and interface modification.

A Valence-Engineered Self-Cascading Antioxidant Nanozyme for the Therapy of Inflammatory Bowel Disease.

Antioxidant treatment strategy by scavenging reactive oxygen species (ROS) is a highly effective disease treatment option. Nanozymes with multiple antioxidant activities can cope with the diverse ROS environment. However, lack of design strategies and limitation of negative correlation for nanozymes with multiple antioxidant activities hindered their development. To overcome these difficulties, here we used ZnMn2 O4 as a model to explore the role of Mn valency at the octahedral site via a valence-engineered strategy, and found that its multiple antioxidant activities are positively correlated with the content of Mn4+ . Therefore, through this strategy, a self-cascading antioxidant nanozyme LiMn2 O4 was constructed, and its efficacy was verified at the cellular level and in an inflammatory bowel disease model. This work not only provides guidance for the design of multiple antioxidant nanozymes, but also broadens the biomedical application potential of multiple antioxidant nanozymes.

Structurally Engineered Light-Responsive Nanozymes for Enhanced Substrate Specificity.

Mimicking enzyme specificity via construction of on-demand geometric structures on nanozymes is of great interest in recent years. Although building substrate-specific polymers on nanozymes has achieved great success, polymer-blocked active sites would inevitably lead to decreased activity of nanozymes. Here, we have developed three photoactive metal-organic framework (MOF)-based nanozymes (called 2D-TCPP, 3D-TCPP, and AD-TCPP), which have different geometric structures as well as unshielded active sites. Together with their structural variations and excellent photoresponsive oxidase-like activities, these photoactive nanozymes exhibit structure-dependent specificity for three kinds of substrates (typical oxidase substrates, organic pollutants, and antioxidants). Moreover, AD-TCPP and 3D-TCPP show potential applications for environmental protection and bioanalysis, respectively. This work offers a promising approach to the development of nanozymes with enzyme-like specificity.

In vitro measurement of superoxide dismutase-like nanozyme activity: a comparative study.

Analyzing the SOD-like activity of nanozymes in vitro is of great importance for identifying new nanozymes and predicting their potential biological effects in vivo. However, false negative or positive results occasionally occur due to the mismatch between the detection methods and nanozymes. Here, five typical SOD-like nanozymes, including CeO2, Mn3O4, Prussian blue (PB), PCN222-Mn, and Pt NPs, have been used to evaluate the sensitivity and accuracy of several commonly used in vitro detection methods. By systematically analyzing the detection results, several precautions have been taken. (1) The hydroethidine (HE) probe could be disturbed by the nanozyme with oxidative ability. (2) The nitro blue tetrazolium (NBT) probe has a moderate sensitivity due to the poor water solubility of its reduced product. (3) The water-soluble tetrazolium salt (WST)-8 probe has a higher sensitivity than both NBT and iodonitrotetrazolium chloride (INT). (4) The detection system using the irradiation of riboflavin to produce ˙O2- might be interfered by the nanozyme with photosensibility. (5) Both the quality of DMPO and incubation time are important factors for electron paramagnetic resonance (EPR) measurement. This study will be useful for choosing more suitable in vitro detection methods of SOD-like activity for nanozymes in the future.

Estrogen inhibits vascular calcification in rats via hypoxia-induced factor-1α signaling.

OBJECTIVE: Calcification serves as a surrogate for atherosclerosis-associated vascular diseases, and coronary artery calcification is mediated by multiple pathogenic factors. Estrogen is a known factor that protects the arterial wall against atherosclerosis, but its role in the coronary artery calcification development remains largely unclear. This study tested the hypothesis that estrogen inhibits coronary artery calcification via the hypoxia-induced factor-1α pathway. METHODS: Eight-week-old healthy female Sprague-Dawley rats were castrated, and vitamin D3 was administered orally to establish. Hypoxia-induced factor-1 inhibitor was administered to test its effect on vascular calcification and expression of bone morphogenetic protein 2 and runt-related transcription factor-2. Vascular smooth muscle cell calcification was induced with CaCl2 in rat aortic smooth muscle cells in the presence or absence of E2(17ß-estradiol) and bone morphogenetic protein 2 siRNA intervention. RESULTS: The estrogen levels in ovariectomized rats were significantly decreased, as determined by ELISA. Expression of hypoxia-induced factor-1α mRNA and protein was significantly increased in vascular cells with calcification as compared to those without calcification (p < 0.01). E2 treatment decreased the calcium concentration in vascular cell calcification and cell calcium nodules in vitro (p < 0.05). E2 also lowered the levels of hypoxia-induced factor-1α mRNA and protein (p < 0.01). Oral administration of the hypoxia-induced factor-1α inhibitor dimethyloxetane in castrated rats alleviated vascular calcification and expression of osteogenesis-related transcription factors, bone morphogenetic protein 2 and RUNX2 (p < 0.01). Finally, bone morphogenetic protein 2 siRNA treatment decreased the levels of p-Smad1/5/8 in A7r5 calcification cells (p < 0.01). CONCLUSION: Estrogen deficiency enhances vascular calcification. Treatment with estrogen reduces the expression of hypoxia-induced factor-1α as well as vascular calcification in rats. The estrogen effects occur in a fashion dependent on hypoxia-induced factor-1α regulation of bone morphogenetic protein-2 and downstream Smad1/5/8.

A multi-element flame retardant containing boron and double-bond structure for enhancing mechanical properties and flame retardancy of epoxy resins.

A multi-element synergistic flame retardant with double-bond structure was synthesized and added to epoxy resin (EP) to obtain EP composites with high flame retardant and mechanical properties. The study demonstrated that the DOPO-KhCPA-5 composite, containing 5 wt% of DOPO, exhibits the limiting oxygen index (LOI) value of 32%, indicating a high resistance to combustion. Additionally, it successfully meets the UL-94 V-0 grade, indicating excellent self-extinguishing properties. The DOPO-KhCPA-5 compound exhibited a 48.7% decrease in peak heat release rate (PHRR) and a 7.2% decrease in total heat release (THR) compared to pure EP. The inclusion of double-bonded architectures in the DOPO-KhCPA-5 composites led to a significant enhancement in both the tensile strength and tensile modulus. Specifically, the tensile strength increased by 38.5% and the tensile modulus by 57.9% compared to pure EP. This improvement can be attributed to the formation of a fully interpenetrating network of macromolecular chain structures by DOPO-KhCPA within the EP matrix. This network increased the entanglement between molecular chains, resulting in positive effects on the mechanical properties of the EP. Multi-element of DOPO-KhCPA exhibits a synergistic effect, providing condensed and noncombustible gas-phase flame retardancy. Additionally, the mechanical properties were improved with the introduction of flame retardants due to the good impact of double-bond cross-linking. The effectiveness of DOPO-KhCPA as an additive for developing high-performance EP with significant potential applications has been proven.

A NAD(P)H oxidase mimic for catalytic tumor therapy via a deacetylase SIRT7-mediated AKT/GSK3ß pathway.

Nicotinamide adenine dinucleotide (NADH) and its phosphorylated form, NADPH, are essential cofactors that play critical roles in cell functions, influencing antioxidation, reductive biosynthesis, and cellular pathways involved in tumor cell apoptosis and tumorigenesis. However, the use of nanomaterials to consume NAD(P)H and thus bring an impact on signaling pathways in cancer treatment remains understudied. In this study, we employed a salt template method to synthesize a carbon-coated-cobalt composite (C@Co) nanozyme, which exhibited excellent NAD(P)H oxidase (NOX)-like activity and mimicked the reaction mechanism of natural NOX. The C@Co nanozyme efficiently consumed NAD(P)H within cancer cells, leading to increased production of reactive oxygen species (ROS) and a reduction in mitochondrial membrane potential. Meanwhile, the generation of the biologically active cofactor NAD(P)+ promoted the expression of the deacetylase SIRT7, which in turn inhibited the serine/threonine kinase AKT signaling pathway, ultimately promoting apoptosis. This work sheds light on the influence of nanozymes with NOX-like activity on cellular signaling pathways in tumor therapy and demonstrates their promising antitumor effects in a tumor xenograft mouse model. These findings contribute to a better understanding of NAD(P)H manipulation in cancer treatment and suggest the potential of nanozymes as a therapeutic strategy for cancer therapy.

Fluorophore and nanozyme-functionalized DNA walking: A dual-mode DNA logic biocomputing platform for microRNA sensing in clinical samples.

Inspired by the programmability and modifiability of nucleic acids, point-of-care (POC) diagnostics for nucleic acid target detection is evolving to become more diversified and intelligent. In this study, we introduce a fluorescent and photothermal dual-mode logic biosensing platform that integrates catalytic hairpin assembly (CHA), toehold-mediated stand displacement reaction (SDR) and a DNA walking machine. Dual identification and signal reporting modules are incorporated into DNA circuits, orchestrated by an AND Boolean logic gate operator and magnetic beads (MBs). In the presence of bispecific microRNAs (miRNAs), the AND logic gate activates, driving the DNA walking machine, and facilitating the collection of hairpin DNA stands modified with FAM fluorescent group and CeO2@Au nanoparticles. The CeO2@Au nanoparticles, served as a nanozyme, can oxidize TMB into oxidation TMB (TMBox), enabling a near-infrared (NIR) laser-driven photothermal effect following the magnetic separation of MBs. This versatile platform was employed to differentiate between plasma samples from breast cancer patients, lung cancer patients, and healthy donors. The thermometer-readout transducers, derived from the CeO2@Au@DNA complexes, provided reliable results, further corroborated by fluorescence assays, enhancing the confidence in the diagnostics compared to singular detection method. The dual-mode logic biosensor can be easily customized to various nucleic acid biomarkers and other POC signal readout modalities by adjusting recognition sequences and modification strategies, heralding a promising future in the development of intelligent, flexible diagnostics for POC testing.

Bioinspired Nanozymes as Nanodecoys for Urinary Tract Infection Treatment.

Urinary tract infections (UTIs), common bacterial infections in communities and medical facilities, are mainly mediated by FimH. The glycan sites of the uromodulin protein play a crucial role in protecting against UTIs by interacting with FimH. A bioinspired approach using glycan-FimH interactions may effectively reduce bacteria through an antiadhesive mechanism, thereby curbing bacterial resistance. However, typical antiadhesive therapy alone fails to address the excessive reactive oxygen species and inflammatory response during UTIs. To bridge this gap, antioxidant nanozymes with antiadhesive ability were developed as nanodecoys to counter bacteria and inflammation. Specifically, ultrasmall dextran-coated ceria (DEC) was engineered to address UTIs, with dextran blocking FimH adhesion and ceria exhibiting anti-inflammatory properties. DECs, metabolizable by the kidneys, reduced bacterial content in the urinary tract, mitigating inflammation and tissue damage. In murine models, DECs successfully treated acute UTIs, repeated infections, and catheter-related UTIs. This dual approach not only highlights the potential of nanozymes for UTIs but also suggests applicability to other FimH-induced infections in the lungs and bowels, marking a significant advancement in nanozyme-based clinical approaches.

Fe3N-decorated porous carbon frameworks from wheat flour with dual enzyme-mimicking activities for organic pollutant degradation.

Organic pollutants produced during industrial production are putting more stress on natural water resources. It is a considerable challenge to realize water remediation from organic pollutants in a cost-effective way. Here, we report a feasible method to fabricate Fe3N-decorated porous carbon frameworks (F/M-Fe) by one-step pyrolysis of wheat flour, melamine and metal ions. The prepared F/M-Fe possessing intrinsic peroxidase (POD)- and catalase (CAT)-like activities could effectively remove organic pollutants, which could be deduced from the degradation of methylene blue trihydrate (MB), rhodamine B (RhB), and tetracycline (TC) as pollutant simulants, as well as excess H2O2 without consuming additional resources and energy. The degradation process was facilitated by the primary active intermediates of ˙OH and 1O2 in the catalytic pathway, with efficiencies of 95.8% for MB, 91.6% for RhB, and 92.3% for TC achieved within 10, 50, and 70 min, respectively. Thanks to the encouraging recycling behavior and well-conditioned tolerance, F/M-Fe shows satisfactory catalytic performance on a proof-of-concept filter-type device for MB degradation. In addition, F/M-Fe could reduce organic pollutants to a safe level, under which zebrafish can survive well, which exhibited the potential value of F/M-Fe in water remediation.

Recent advances in metal-family flame retardants: a review.

The use of polymer materials is inextricably linked to our manufacturing life. However, most of them are easily combusted in the air and the combustion process generates a large amount of toxic fumes and dangerous smoke. This can result in injuries and property damage, as well as limiting their use. It is essential to enhance the flame-retardant properties and smoke suppression performance by using multiple flame retardants. Metal-based flame retardants have a unique chemical composition. They are environmentally friendly flame retardants, which can impart good smoke suppression, flame retardancy to polymers and further reduce the production of toxic gases. The differences in the compounds formed between the transition metals and the main group metals make them act differently as flame retardants for polymers. As a result, this study presents the research progress and flame-retardant mechanism of flame-retardant polymers for flame retardants from different groups of metals in the periodic table of elements in a systematic manner. In view of the differences between the main group metals and transition metals, the mechanism of their application in flame retardant polymer materials is carefully detailed, as are their distinct advantages and disadvantages. And ultimately, prospects for the development of transition metals and main group metals are outlined. It is hoped that this paper will provide valuable references and insights for scholars in the field.

Nanozyme-Cosmetic Contact Lenses for Ocular Surface Disease Prevention.

Efficiently balancing excess reactive oxygen species (ROS) caused by various factors on the ocular surface is a promising strategy for preventing the development of ocular surface diseases (OSDs). Nevertheless, the conventional topical administration of antioxidants is limited in efficacy due to poor absorption, rapid metabolism, and irreversible depletion, which impede their performance. To address this issue, contact lenses embedded with antioxidant nanozymes that can continuously scavenge ROS, thereby providing an excellent preventive effect against OSDs are developed. Specifically, Prussian blue family nanozymes are chosen based on their multiple antioxidant enzyme-like activities and excellent biocompatibility. The diverse range of colors made them promising candidates for the development of cosmetic contact lenses (CCLs) as a substitute for conventional pigments. The efficacy of nanozyme-CCLs is demonstrated in rabbits and rats exposed to a high risk of developing OSDs. These OSDs' prevention nanozyme-CCLs can pave the way for CCLs toward powerful wearable biomedical devices and provide novel strategies for the rational utilization of nanomaterials in clinical practice.

A probiotic nanozyme hydrogel regulates vaginal microenvironment for Candida vaginitis therapy.

Molecular therapeutics are limited for Candida vaginitis because they damage normal cells and tissues of vagina, aggravating the imbalance of vaginal microbiota and increasing the recurrence. To tackle this limitation, through the combination of peroxidase-like rGO@FeS2 nanozymes [reduced graphene oxide (rGO)] with Lactobacillus-produced lactic acid and H2O2, a responsive hyaluronic acid (HA) hydrogel rGO@FeS2/Lactobacillus@HA (FeLab) is developed. FeLab has simultaneous anti-Candida albicans and vaginal microbiota-modulating activities. In particular, the hydroxyl radical produced from rGO@FeS2 nanozymes and Lactobacillus kills C. albicans isolated from clinical specimens without affecting Lactobacillus. In mice with Candida vaginitis, FeLab has obvious anti-C. albicans activity but hardly damages vaginal mucosa cells, which is beneficial to vaginal mucosa repair. Moreover, a higher proportion of Firmicutes (especially Lactobacillus) and a decrease in Proteobacteria reshape a healthy vaginal microbiota to reduce the recurrence. These results provide a combined therapeutic of nanozymes and probiotics with translational promise for Candida vaginitis therapy.

An Organometallic Flame Retardant Containing P/N/S-Cu2+ for Epoxy Resins with Reduced Fire Hazard and Smoke Toxicity.

Epoxy resins (EPs) have superior physical and chemical features and are used in a wide range of applications in everyday life and engineering. However, its poor flame-retardant performance has hindered its wide application. Over the past decades of extensive research, metal ions have received increasing attention for their highly effective smoke suppression properties. In this work, we used an "aldol-ammonia condensation" reaction to structure the Schiff base structure, together with grafting using the reactive group on 9,10-dihydro-9-oxa-10-phospha-10-oxide (DOPO). Then, Cu2+ was used to replace Na+ to obtain DCSA-Cu flame retardant with smoke suppression properties. Attractively, DOPO and Cu2+ can collaborate, thus effectively improving EP fire safety. At the same time, the addition of a double-bond initiator at low temperatures allows small molecules to form in situ macromolecular chains through the EP network, enhancing the tightness of the EP matrix. With the addition of 5 wt % flame retardant, the EP shows well-defined fire resistance, and the limiting oxygen index (LOI) reaches 36% with a significant reduction in the values of peak heat release (29.72%). In addition, the glass-transition temperature (Tg) of the samples with in situ formations of macromolecular chains was improved, and the physical properties of EP materials are also retained.