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In this study, 3,4-ethylenedioxythiophene derivative conjugated monomer 4-(dihexylamino)-9,12-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-7H-benzo [de]benzo[4,5]imidazo[2,1-a]isoquinolin-7-one (EDOTBN) was synthesized and electropolymerized on pencil graphite electrode (PGE) to fabricate a highly stable and sensitive sensor for glucose detection for the first time. The structurally high conjugation of the monomer and the effect of increasing the conductivity of the gold nanoparticles increased the covalent bonding ability of the enzyme to the modified electrode surface and provided an excellent immobilization. PGE/p(EDOTBN)/AuNPs/GOx designed biosensor was characterized by a wide linear glucose determination range between 1.169 × 10–2 and 10 mM with a limit of detection of 0.008461 mM and a sensitivity of 38.365 µA/mMcm2. Furthermore, the prepared bioelectrode showed storage stability for 4 weeks. Recovery studies were also carried out to check the accuracy of the developed bioelectrode and the glucose concentration in commercial samples was determined accurately. [ABSTRACT FROM AUTHOR]

Rivastigmine is one of the several pharmaceuticals widely prescribed for the treatment of Alzheimer's disease. However, its practical synthesis still faces many issues, such as the involvement of toxic metals and harsh reaction conditions. Herein, we report a chemo‐enzymatic synthesis of Rivastigmine. The key chiral intermediate was synthesized by an engineered alcohol dehydrogenase from Lactobacillus brevis (LbADH). A semi‐rational approach was employed to improve its catalytic activity and thermal stability. Several LbADH variants were obtained with a remarkable increase in activity and melting temperature. Exploration of the substrate scope of these variants demonstrated improved activities toward various ketones, especially acetophenone analogs. To further recycle and reuse the biocatalyst, one LbADH variant and glucose dehydrogenase were co‐immobilized on nanoparticles. By integrating enzymatic and chemical steps, Rivastigmine was successfully synthesized with an overall yield of 66 %. This study offers an efficient chemo‐enzymatic route for Rivastigmine and provides several efficient LbADH variants with a broad range of potential applications. [ABSTRACT FROM AUTHOR]

Framework and polymeric nanoreactors (NRs) have distinct advantages in improving chemical reaction efficiency in the tumor microenvironment (TME). Nanoreactor‐loaded oxidoreductase enzyme is activated by tumor acidity to produce H2O2 by increasing tumor oxidative stress. High levels of H2O2 induce self‐destruction of the vesicles by releasing quinone methide to deplete glutathione and suppress the antioxidant potential of cancer cells. Therefore, the synergistic effect of the enzyme‐loaded nanoreactors results in efficient tumor ablation via suppressing cancer‐cell metabolism. The main driving force would be to take advantage of the distinct metabolic properties of cancer cells along with the high peroxidase‐like activity of metalloenzyme/metalloprotein. A cascade strategy of dual enzymes such as glucose oxidase (GOx) and nitroreductase (NTR) wherein the former acts as an O2‐consuming agent such as overexpression of NTR and further amplified NTR‐catalyzed release for antitumor therapy. The design of cascade bioreductive hypoxia‐responsive drug delivery via GOx regulates NTR upregulation and NTR‐responsive nanoparticles. Herein, we discuss tumor hypoxia, reactive oxygen species (ROS) formation, and the effectiveness of these therapies. Nanoclusters in cascaded enzymes along with chemo‐radiotherapy with synergistic therapy are illustrated. Finally, we outline the role of the nanoreactor strategy of cascading enzymes along with self‐synergistic tumor therapy. [ABSTRACT FROM AUTHOR]

[Display omitted] The lack of selective release ability in the tumor microenvironment and the limited efficacy of monotherapy are important factors that limit the current use of carbon monoxide (CO) donors for tumor therapy. Herein, inspired by endogenous biochemical reactions in vivo , one kind of CO-releasing nanomotor was designed for the multimodal synergistic treatment of tumor. Specifically, glucose oxidase (GOx) and 5-aminolevulinic acid (5-ALA) were co-modified onto metal–organic framework material (MIL-101) to obtain MIL-GOx-ALA nanomotors (M-G-A NMs), which exhibit excellent biocompatibility and degradation ability in tumor microenvironment. Subsequently, the released 5-ALA generates CO in the tumor microenvironment through an endogenous reaction and further acts on mitochondria to release large amounts of reactive oxygen species (ROS), which directly kill tumor cells. Furthermore, the produced ROS and the degradation products of M-G-A NMs can also provide the reaction substrate for the Fenton reaction, thereby enhancing chemodynamic therapy (CDT) and inducing apoptosis of tumor cells. Both in vitro and in vivo experimental data confirm the successful occurrence of the above process, and the combination of CO gas therapy/enhanced CDT can effectively inhibit tumor growth. This CDT-enhancing agent designed based on endogenous biochemical reactions has good prospects for tumor treatment application. [ABSTRACT FROM AUTHOR]

Mesoporous silica materials (MSMs) are widely used materials in many applications due to their diverse pore structures. However, the electrical conductivity of MSMs is poor which limits their use in electrochemical applications. In this study, widely used MSMs of different structural properties such as MCM-41, MCM-48, SBA-15, and SBA-16 were synthesized and reinforced with graphene oxide (GO) to obtain conductive composite supports for enzyme immobilization. MSMs were first synthesized using a hydrothermal method and characterized by Fourier-transform infrared spectroscopy, X-ray crystallography, scanning electron microscopy/energy dispersive X-ray, and MAPPING techniques. Aqueous dispersion of GO:MSM composites were prepared with as-synthesized materials and coated on screen-printed electrodes (SPE). The best composites were chosen based on their electroanalytical performance. Glucose oxidase (GOx) was then immobilized on modified SPEs using a simple drop-casting method to produce enzymatic electrodes. The electroanalytical performance of the enzymatic electrodes was investigated using different glucose concentrations to demonstrate biocatalytic activity. Stability tests were performed using intraday and interday measurements which revealed that SPE/GO:MCM-41/GOx electrode showed a more stable performance (3-folds) than SPE/GO/GOx electrode. This study presents an investigation of MSM mixed with GO in enzymatic electrochemical systems providing insight into the use of such materials to preserve enzyme activity. [ABSTRACT FROM AUTHOR]

Photothermal therapy (PTT) has a great prospect in further improving tumor therapeutic outcomes, whereas its efficiency is restrained by low light penetration, excessive heat damage to normal tissues, up‐regulated heat shock proteins (HSPs), and limited effect of single treatment. Herein, an enzyme‐engineered coppery nanozyme based on dendritic mesoporous coppery carbon nanosphere as the cornerstone to load with glucose oxidase (GOx) followed by modification with hyaluronic acid is constructed. Density functional theory calculations indicate that the obtained coppery nanozyme exhibits peroxidase and glutathione oxidase mimicking activities to improve hydroxyl radicals (•OH) production. Furthermore, both the generation of •OH production and GOx‐induced energy supply blockade can reduce HSPs expression to enhance the mild PTT (η = 34.9 %) of coppery nanozyme upon the irradiation of 1064 nm laser, and in turn, accelerate the catalytic processes of coppery nanozyme for more generation of •OH. Last but not least, the introduction of copper can induce lipoylated protein dihydrolipoamide S‐acetyltransferase aggregation to cause cellular cuproptosis. Due to the synergy of multiple therapies, the tumor inhibition rate can reach 93.4%. Overall, this work provides an effective strategy for potential tumor treatment on the basis of synergistic therapies. [ABSTRACT FROM AUTHOR]

CO gas therapy has attracted enormous attention in tumor therapy due to the abilities of mitochondrial damage and inhibition of cellular respiration. However, the inefficient and random release of CO greatly limit its application. Taking this into account, the study constructs an acid‐unlocked nanostructure based on MPDA‐MnCO‐GOx@DSNPs, designated as MMGD. The nanostructure enables tumor microenvironment (TME) specific enzyme and CO prodrug (manganese carbonyl, MnCO) cascade reaction, thus facilitating CO release in situ. Mesoporous polydopamine (MPDA) can provide the space for MnCO and glucose oxidase (GOx) loading. Especially, lanthanide (Ln3+)‐doped down‐shifting luminescent nanoparticles (DSNPs) can not only serve as the near‐infrared II (NIR‐II) fluorescence imaging probe, but also act as the acid‐unlocked gating switch. The slightly acidic TME can render the dissociation of DSNPs, thus exposing GOx and releasing MnCO. The catalytic reaction of GOx can produce H2O2 and create a more acidic environment, which facilitates the CO generation in situ, leading to mitochondrial damage by reducing cytochrome c oxidase activity and adenosine triphosphate (ATP) levels. Meanwhile, MPDA has the NIR light absorption capability for photothermal therapy (PTT). This study provides an ingenious strategy for efficient and controllable CO gas, starvation, and PTT of tumor guided by NIR‐II fluorescence imaging. [ABSTRACT FROM AUTHOR]

Nanomedicine has reshaped the landscape of cancer treatment. However, its efficacy is still hampered by innate tumor defense systems that rely on adenosine triphosphate (ATP) for fuel, including damage repair, apoptosis resistance, and immune evasion. Inspired by the naturally enzymatic reaction of glucose oxidase (GOx) with glucose, here a novel "two birds with one stone" technique for amplifying enzyme‐mediated tumor apoptosis and enzyme‐promoted metabolic clearance is proposed and achieved using GOx‐functionalized rhenium nanoclusters‐doped polypyrrole (Re@ReP‐G). Re@ReP‐G reduces ATP production while increasing H2O2 concentrations in the tumor microenvironment through GOx‐induced enzymatic oxidation, which in turn results in the downregulation of defense (HSP70 and HSP90) and anti‐apoptotic Bcl‐2 proteins, the upregulation of pro‐apoptotic Bax, and the release of cytochrome c. These processes are further facilitated by laser‐induced hyperthermia effect, ultimately leading to severe tumor apoptosis. As an enzymatic byproduct, H2O2 catalyzes the conversion of rhenium nanoclusters in Re@ReP‐G nanostructures into rhenate from the outside in, which accelerates their metabolic clearance in vivo. This Re@ReP‐G‐based "two birds with one stone" therapeutic strategy provides an effective tool for amplifying tumor apoptosis and safe metabolic mechanisms. [ABSTRACT FROM AUTHOR]

In this study we examine effect of the solvent ratio on TiO 2 physical and photoelectrochemical properties utilizing economical hydrothermal process. Sample properties were examined using XRD, SEM, Raman, UV–vis, PL, photocurrent, Mott–Schottky, and EIS measurements. XRD patterns revealed that TiO 2 samples represent a polycrystalline nature with a Tetragonal structure. Peaks at 609, 144, and 443 cm−1 were observed in Raman spectra indicating the production of the TiO 2 rutile phase. SEM images showed that TiO 2 nanorods formed evenly with square top facets and a tetragonal form. UV–vis results displayed an optical absorption edge between 386 and 405 nm which is associated with the band gap of TiO 2 NRs films. The generated TiO 2 NRs films exhibit n-type semiconductor behavior according to the photocurrent measurements. Mott-Schottky experiments indicated that the donor density and flat band potential varied with decreased acid ratio from 1.55 × 1018 to 3.33 × 1018 cm−3 and-0.47 to-0.72 V, respectively. As observed by EIS, the resistivity to charge transfer declined, reaching its lowest level at 5:11 ml, indicating improvement of electrochemical activity and structural properties with decreasing the HCl concentration. Additionally, the fabricated TiO2 NRs films was employed as biosensor for glucose where a fast amperometric response and good operating stability were detected. [ABSTRACT FROM AUTHOR]

The inorganic content and the catalytic performance pose metal‐loaded enzyme nanoflowers as promising candidates for developing bioelectrodes capable of functioning without the external addition of a redox mediator. However, these protein‐inorganic hybrids have yet to be successfully applied in combination with electrode materials. Herein, the synthesis procedure of these bionanomaterials is reproposed to precisely control the morphology, composition, and performance of this particular protein‐mineral hybrid, formed by glucose oxidase and cobalt phosphate. This approach aims to enhance the adherence and electron mobility between the enzyme and a carbon electrode. The strategy relies on dressing the protein in a tailored thin nanogel with multivalent chemical motifs. The functional groups of the polymer facilitate the fast protein sequence‐independent biomineralization. Furthermore, the engineered enzymes enable the fabrication of robust cobalt‐loaded enzyme inorganic hybrids with exceptional protein loads, exceeding 90% immobilization yields. Notably, these engineered biohybrids can be readily deposited onto flat electrode surfaces without requiring chemical pre‐treatment. The resulting bioelectrodes are robust and exhibit electrochemical responses even without the addition of a redox mediator, suggesting that cobalt complexes promote electron wiring between the active site of the enzyme and the electrode. [ABSTRACT FROM AUTHOR]

Radiotherapy-induced immune activation holds great promise for optimizing cancer treatment efficacy. Here, we describe a clinically used radiosensitizer hafnium oxide (HfO2) that was core coated with a MnO2 shell followed by a glucose oxidase (GOx) doping nanoplatform (HfO2@MnO2@GOx, HMG) to trigger ferroptosis adjuvant effects by glutathione depletion and reactive oxygen species production. This ferroptosis cascade potentiation further sensitized radiotherapy by enhancing DNA damage in 4T1 breast cancer tumor cells. The combination of HMG nanoparticles and radiotherapy effectively activated the damaged DNA and Mn2+-mediated cGAS-STING immune pathway in vitro and in vivo. This process had significant inhibitory effects on cancer progression and initiating an anticancer systemic immune response to prevent distant tumor recurrence and achieve long-lasting tumor suppression of both primary and distant tumors. Furthermore, the as-prepared HMG nanoparticles "turned on" spectral computed tomography (CT)/magnetic resonance dual-modality imaging signals, and demonstrated favorable contrast enhancement capabilities activated by under the GSH tumor microenvironment. This result highlighted the potential of nanoparticles as a theranostic nanoplatform for achieving molecular imaging guided tumor radiotherapy sensitization induced by synergistic immunotherapy. [ABSTRACT FROM AUTHOR]

Safe, accurate, and reliable analysis of urinary biomarkers is clinically important for early detection and monitoring of the progression of chronic kidney disease (CKD), as it has become one of the world's most prevalent non-communicable diseases. However, current technologies for measuring urinary biomarkers are either time-consuming and limited to well-equipped hospitals or lack the necessary sensitivity for quantitative analysis and post a health risk to frontline practitioners. Here we report a robust paper-based dual functional biosensor, which is integrated with the clinical urine sampling vial, for the simultaneous and quantitative analysis of pH and glucose in urine. The pH sensor was fabricated by electrochemically depositing IrOx onto a paper substrate using optimised parameters, which enabled an ultrahigh sensitivity of 71.58 mV pH-1. Glucose oxidase (GOx) was used in combination with an electrochemically deposited Prussian blue layer for the detection of glucose, and its performance was enhanced by gold nanoparticles (AuNPs), chitosan, and graphite composites, achieving a sensitivity of 1.5 μA mM-1. This dual function biosensor was validated using clinical urine samples, where a correlation coefficient of 0.96 for pH and 0.98 for glucose detection was achieved with commercial methods as references. More importantly, the urine sampling vial was kept sealed throughout the sample-to-result process, which minimised the health risk to frontline practitioners and simplified the diagnostic procedures. This diagnostic platform, therefore, holds high promise as a rapid, accurate, safe, and user-friendly point-of-care (POC) technology for the analysis of urinary biomarkers in frontline clinical settings. [ABSTRACT FROM AUTHOR]

17β-Estradiol (E2) is an important endogenous estrogen, which disturbs the endocrine system and poses a threat to human health because of its accumulation in the human body. Herein, a biofuel cell (BFC)-based self-powered electrochemical aptasensor was developed for E2 detection. Porous carbon nanocage/gold nanoparticle composite modified indium tin oxide (CNC/AuNP/ITO) and glucose oxidase modified CNC/AuNP/ITO were used as the biocathode and bioanode of BFCs, respectively. [Fe(CN)6]3− was selected as an electroactive probe, which was entrapped in the pores of positively charged magnetic Fe3O4 nanoparticles (PMNPs) and then capped with a negatively charged E2 aptamer to form a DNA bioconjugate. The presence of the target E2 triggered the entrapped [Fe(CN)6]3− probe release due to the removal of the aptamer via specific recognition, which resulted in the transfer of electrons produced by glucose oxidation at the bioanode to the biocathode and produced a high open-circuit voltage (EOCV). Consequently, a "signal-on" homogeneous self-powered aptasensor for E2 assay was realized. Promisingly, the BFC-based self-powered aptasensor has particularly high sensitivity for E2 detection in the concentration range of 0.5 pg mL−1 to 15 ng mL−1 with a detection limit of 0.16 pg mL−1 (S/N = 3). Therefore, the proposed BFC-based self-powered electrochemical aptasensor has great promise to be applied as a successful prototype of a portable and on-site bioassay in the field of environment monitoring and food safety. [ABSTRACT FROM AUTHOR]

Background: The pre-analytical (PA) phase is the most vulnerable phase of the laboratory testing procedure, with critical procedures-collection, handling, sample transport, and time and temperature of sample storage. This study aimed to examine the stability of basic biochemical parameters depending on the samples' storage conditions and the number of freeze-thaw cycles (FTCs). In parallel, the presence of sample bacterial contamination during routine laboratory work was examined. Methods: Two plasma pools (ethylenediaminetetraacetic acid (EDTA), and sodium-fluoride/potassium oxalate plasma (NaF)) were stored at +4 °C/-20 °C. Total chole - sterol (TC), glucose, triglycerides (TG), urea, and albumin concentrations were measured using BioSystems reagents (cholesterol oxidase/peroxidase, glucose oxidase/per - oxidase, glycerol phosphate oxidase/peroxidase, urease/salicylate, and bromcresol green method, respectively) on Ilab 300+. Sample bacterial contamination was determined by 16S rRNA sequence analysis. The expe - riment encompassed a 5 day-period: Day 1-fresh sample, Day 2-1st FTC, Day 3-2nd FTC, Day 4-3rd FTC, Day 5-4th FTC. The appearance of bacteria in two consecutive samples was the experiment's endpoint. Results: During 4 FTCs, there were no changes in plasma urea concentrations. Glucose was stable in EDTA +4 °C and NaF -20 °C until the 3rd FTC (P=0.008, P=0.042, respectively). TG concentrations changed significantly in the EDTA -20 °C sample after 1st and 4th FTCs (P=0.022, P=0.010, respectively). In NaF samples, no bacterial contamination was observed during 4 FTCs. Conclusion: Urea and glucose concentrations were robust. Changes in lipid concentrations after FTCs follow complex patterns. Bacterial growth was not observed in NaF plasma samples. This can promote NaF use in analytical procedures in which bacterial contamination affects the quality of analysis. [ABSTRACT FROM AUTHOR]

The development of nanozymes, artificial enzymes made from inorganic nanoparticles, is widely studied due to their affordability, durability, and strength. Gold nanoparticles (AuNPs) are employed to imitate peroxidase, glucose oxidase, lactate oxidase, superoxide dismutase, and catalase. The last one transforms intracellular hydrogen peroxide into molecular oxygen, whose deficiency is characteristic of the hypoxic tumor microenvironment. Thus, gold nanoparticles are thought to enhance the overall effectiveness of photodynamic therapy. However, the enzyme‐like activity of nanoparticles rapidly decreases in biological media, due to the aggregation and formation of the so‐called "protein corona". In this study, polymeric submicrocapsules loaded with AuNPs and a photodynamic dye are fabricated via Layer‐by‐Layer (LbL) assembly. The enhancement of photodynamic treatment efficacy by in situ production of oxygen by the catalase‐like effect of AuNPs is investigated. Polymeric capsules are thoroughly characterized in terms of physicochemical and catalytic properties, and as a proof of concept, their therapeutic potential is evaluated in vitro. Furthermore, encapsulated AuNPs shows significantly lower aggregation both upon storage and during the reaction course. The results shows that the polymer capsules, containing AuNPs and photodynamic dye, show significantly higher light‐induced cytotoxicity in comparison to the individual photodynamic dye, suggesting a synergistic effect between the formation of molecular oxygen by catalase‐like gold nanozymes and photodynamic action. [ABSTRACT FROM AUTHOR]

An enzymatic fluorescent probe is developed for the selective detection of glucose. In this work, a Bovine Serum Albumin stabilized gold nanocluster (BSA‐AuNCs) was synthesized by microwave assisted method, and it is modified with glucose oxidase, thereby a fluorescent enzymatic sensor (BSA‐AuNCs@GoX) was designed for the sensitive detection of glucose with a limit of detection of 0.03 mM. The red fluorescence exhibited by the probe is quenched by the production of H2O2 on addition of glucose via. a static quenching mechanism from UV visible absorption and Fluorescence lifetime results. The developed probe exhibits good selectivity and sensitivity with other coexisting molecular species such as glycine, creatinine, methionine, histidine, uric acid, albumin, and ions such as sodium, potassium, calcium, magnesium, zinc etc. that appear in the body fluid. The practical applicability was studied in paper strip and extended its reproducibility in biological matrixes such as human serum and urine and found a good recovery percentage of 94–101 %. By this way, we have fabricated an effective fluorescent enzymatic "turn‐off" sensing probe for the detection of glucose. [ABSTRACT FROM AUTHOR]

Directed toward the limitations of natural enzymes in diabetes management, it is possible to design nano-enzymatic structures and modulate the activity as needed to obtain superior materials that are more suitable for the specific application environment. In this work, noble metal–semiconductor composite nanozymes [Te–Au nanowires (NWs)] were designed and their enzyme-like activities were systematically investigated for diabetes management. The results indicated that Te–Au NWs exhibited pH-switching multi-enzyme-like activities and adapted to a wider range of reaction conditions than natural enzymes. The kinetics of their enzyme-catalyzed reactions followed the Michaelis–Menten model, showing their substrate affinity similar to that of natural enzymes. Actually, the nanozymes showed reliable application stability, maintaining more than 80% of various enzyme activities under prolonged or extreme storage conditions. Furthermore, the nanozymes can be flexibly applied to various paths of glucose detection. For example, we constructed three different colorimetric detection methods to achieve the detection of glucose in saliva and blood. All three detection methods showed a wider linear range and lower limit of detection (LOD), among which the most optimal method was the combination of Te–Au NWs and glucose oxidase (GOx), with a linear range of 0.05–4 mM and a LOD of 2.11 μM. In summary, nanozymes with multiple enzyme-like activities have significant advantages and effectively address the limitations of natural enzymes in the application of diabetes management. [ABSTRACT FROM AUTHOR]

Glucose oxidase (GOx) catalyzes the oxidation of D -glucose to D -glucono-1,5-lactone and has a wide range of applications in various industries. However, the strict substrate specificity of GOx hampers its application in the conversion of other abundant sugars such as D -xylose. In this study, the substrate preference of GOx from Aspergillus niger (AnGOx) was engineered using a semi-rational design approach. The mutant T110V/F414L exhibited a 5.7-fold increase in D -xylose oxidation activity compared to that of the wild-type enzyme, which was attributed to its enhanced affinity for the substrate. Molecular dynamics simulations indicated that the T110V and F414L mutations may mitigate the non-productive binding of D -xylose at the entrance of the substrate-binding pocket, and therefore, are beneficial for providing access of its C1 hydroxyl group to the catalytic residues. Moreover, the mutant simultaneously oxidized D -xylose and D -glucose in the corncob hydrolysate to the corresponding aldonic acids when coupled with catalase. These findings provide new insights into substrate recognition by GOx and offer a new method for the utilization of D -xylose from lignocellulosic feedstocks. [ABSTRACT FROM AUTHOR]

Here, we developed magnetically recoverable biocatalysts based on magnetite nanoparticles coated with an ultra-thin layer (about 0.9 nm) of chitosan (CS) ionically cross-linked by sodium tripolyphosphate (TPP). Excessive CS amounts were removed by multiple washings combined with magnetic separation. Glucose oxidase (GOx) was attached to the magnetic support via the interaction with N-hydroxysuccinimide (NHS) in the presence of carbodiimide (EDC) leading to a covalent amide bond. These steps result in the formation of the biocatalyst for D-glucose oxidation to D-gluconic acid to be used in the preparation of pharmaceuticals due to the benign character of the biocatalyst components. To choose the catalyst with the best catalytic performance, the amounts of CS, TPP, NHS, EDC, and GOx were varied. The optimal biocatalyst allowed for 100% relative catalytic activity. The immobilization of GOx and the magnetic character of the support prevents GOx and biocatalyst loss and allows for repeated use. [ABSTRACT FROM AUTHOR]

Considering the application prospects of a cascade catalytic system in biomedical analysis, it remains significant to develop a cascade catalytic system for one-step rapid colorimetric detection. Herein, PVP/NH2-MIL-101(Fe) possessing enhanced peroxidase (POD)-like activity was successfully synthesized by microwave-assisted and polyvinylpyrrolidone (PVP) modification strategies. Then, PVP/NH2-MIL-101(Fe) and glucose oxidase (GOx) were covalently coupled via the bifunctional cross-linker glutaraldehyde, the GOx@PVP/NH2-MIL-101(Fe) with dual enzymatic functional activities (POD-like and GOx activities) was subsequently synthesized. GOx@PVP/NH2-MIL-101(Fe) had strong affinities for the substrates glucose, 3,3',5,5'-tetramethylbenzidine, and hydrogen peroxide. Based on this specific nanozyme GOx@PVP/NH2-MIL-101(Fe), a one-step colorimetric assay for rapid glucose determination was built. This detection method not only took 20 min to analyze but also possessed a linear range of 10–250 µM with a detection limit of 1.05 µM. Furthermore, the cascade catalytic system was applied to determine glucose concentrations in human serum samples. Compared with commercial blood glucose meters, the proposed method was also accurate and effective, making it a candidate method for determining blood glucose. [ABSTRACT FROM AUTHOR]

Recently protein binders have emerged as a promising substitute for antibodies due to their high specificity and low cost. Herein, we demonstrate an electrochemical biosensor chip through the electronic labelling strategy using lead sulfide (PbS) colloidal quantum dots (CQDs) and the unnatural SARS-CoV-2 spike miniprotein receptor LCB. The unnatural receptor can be utilized as a molecular probe for the construction of CQD-based electrochemical biosensor chips, through which the specific binding of LCB and the spike protein is transduced to sensor electrical signals. The biosensor exhibits a good linear response in the concentration range of 10 pg mL−1 to 1 μg mL−1 (13.94 fM to 1.394 nM) with the limit of detection (LOD) being 3.31 pg mL−1 (4.607 fM for the three-electrode system) and 9.58 fg mL−1 (0.013 fM for the HEMT device). Due to the high sensitivity of the electrochemical biosensor, it was also used to study the binding kinetics between the unnatural receptor LCB and spike protein, which has achieved comparable results as those obtained with commercial equipment. To the best of our knowledge, this is the first example of using a computationally designed miniprotein receptor based on electrochemical methods, and it is the first kinetic assay performed with an electrochemical assay alone. The miniprotein receptor electrochemical biosensor based on QDs is desirable for fabricating high-throughput, large-area, wafer-scale biochips. [ABSTRACT FROM AUTHOR]

Fish gelatin (FG)-based wound dressings exhibit superior water absorption capacity, thermal stability, and gelation properties, which enhance the performance of these dressings. In this study, our objective was to investigate the conditions underlying the enzymatic hydrolysis of FG and subsequent cross-linking to prepare high-performance gels. A two-step enzymatic method of protease-catalyzed hydrolysis followed by glutamine transglutaminase (TGase)-catalyzed cross-linking was used to prepare novel high-performance fish gelatin derivatives with more stable dispersion characteristics than those of natural gelatin derivatives. Compared with conventional TGase cross-linked derivatives, the novel derivatives were characterized by an average pore size of 150 μm and increased water solubility (423.06% to 915.55%), water retention (by 3.6-fold to 43.89%), thermal stability (from 313 °C to 323 °C), and water vapor transmission rate, which reached 486.72 g·m−2·24 h−1. In addition, loading glucose oxidase onto the fish gelatin derivatives increased their antibacterial efficacy to >99% against Escherichia coli and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Ferroptosis, a unique iron-dependent mode of cell death characterized by lipid peroxide accumulation, holds significant potential for the treatment of glioblastoma (GBM). However, the effectiveness of ferroptosis is hindered by the limited intracellular ferrous ions (Fe2+) and hydrogen peroxide (H 2 O 2). In this study, a novel near-infrared (NIR)-light-responsive nanoplatform (ApoE-UMSNs-GOx/SRF) based on upconversion nanoparticles (UCNPs) was developed. A layer of mesoporous silica and a lipid bilayer were coated on UCNPs sequentially and loaded with glucose oxidase (GOx) and sorafenib, respectively. Further attachment of the ApoE peptide endowed the nanoplatform with BBB penetration and GBM targeting capabilities. Our results revealed that ApoE-UMSNs-GOx/SRF could efficiently accumulated in the orthotopic GBM and induce amplified ferroptosis when combining with NIR irradiation. The UCNPs mediated the photoreduction of Fe3+ to Fe2+ by converting NIR to UV light, and excess H 2 O 2 was produced by the reaction of glucose with the loaded GOx. These processes greatly promoted the production of ROS, which together with inhibition of system Xc− by the loaded sorafenib, leading to enhanced accumulation of lipid peroxides and significantly improved the antiglioma effect both in vitro and in vivo. Our strategy has the potential to enhance the effectiveness of ferroptosis as a therapeutic approach for GBM. A novel nanoplatform (ApoE-UMSNs-GOx/SRF) for the efficient treatment of glioblastoma through NIR-promoted enhanced ferroptosis. [Display omitted] [ABSTRACT FROM AUTHOR]

Herein, the hybrid nanozyme MnOx NPs/Co3O4 NPs on indium tin oxide coated glass substrate (ITO) was manufactured by imparting the porous morphology with its distinct merits: its surface valence states, oxygen vacancies, large surface area, and abundant active sites. The oxidase-like activity was investigated via the catalytic oxidation of chromogenic substrate in the presence of glucose visualized by the eyes. MnOx NPs containing Mn2+ and Mn3+ have a superior ability to oxidize glucose by reducing dissolved oxygen and producing H2O2. Co3O4 NPs, in turn, reduce H2O2 with concomitant 3,3′,5,5′-tetramethylbenzidine (TMB) oxidization. Thus, the nanozyme mimics the dual roles of glucose oxidase and peroxidase. The oxidaselike activity of hybrid nanozyme for glucose was found to be higher than those of single components. The nanozyme responded to glucose with a linear range from 60 µM to 1200 μM. The acceptable performance is probably due to the facilitated access of glucose to the proximity of the sensor surface. Good reproducibility was accomplished by virtue of the meticulous construction of NPs. Without functionalization and enzyme utilization, the fabricated nanozyme holds promise as a substitute for peroxidase and oxidase for detecting glucose. [ABSTRACT FROM AUTHOR]

Microneedle array systems loaded with responsive nanoparticles have received increasing attention due to the advantages of good drug stability, targeting ability, controlled release of drugs, high bioavailability, painlessness, and good patient compliance. Compared with oral drug delivery, microneedle transdermal drug delivery eliminates the need to pass through the gastrointestinal tract and liver, reducing the metabolic consumption of drugs by first‐pass effect. While compared with intravenous drug delivery, microneedle transdermal drug delivery reduces patient discomfort and does not require professional administration. However, there are few review articles on microneedles loaded with responsive nanoparticles. Herein, the current researches on microneedles loaded with specific responsive nanoparticles such as glucose‐responsive, pH‐responsive, enzyme‐responsive, light‐responsive, magnetic‐responsive, ultrasound‐responsive, and multiresponsive, and the biomedical application of these microneedle array systems are summarized. In addition, the challenges and prospects of microneedle strategies loaded with responsive nanoparticles are briefly discussed, which will facilitate the development of such versatile drug‐delivery strategy. [ABSTRACT FROM AUTHOR]

Ethyl (S)-4-chloro-3-hydroxybutyrate ((S)-CHBE) is an important chiral intermediate in the synthesis of the cholesterol-lowering drug atorvastatin. Studying the use of SpyTag/SpyCatcher and SnoopTag/SnoopCatcher systems for the asymmetric reduction reaction and directed coupling coenzyme regeneration is practical for efficiently synthesizing (S)-CHBE. In this study, Spy and Snoop systems were used to construct a double-enzyme directed fixation system of carbonyl reductase (BsCR) and glucose dehydrogenase (BsGDH) for converting 4-chloroacetoacetate (COBE) to (S)-CHBE and achieving coenzyme regeneration. We discussed the enzymatic properties of the immobilized enzyme and the optimal catalytic conditions and reusability of the double-enzyme immobilization system. Compared to the free enzyme, the immobilized enzyme showed an improved optimal pH and temperature, maintaining higher relative activity across a wider range. The double-enzyme immobilization system was applied to catalyze the asymmetric reduction reaction of COBE, and the yield of (S)-CHBE reached 60.1% at 30 °C and pH 8.0. In addition, the double-enzyme immobilization system possessed better operational stability than the free enzyme, and maintained about 50% of the initial yield after six cycles. In summary, we show a simple and effective strategy for self-assembling SpyCatcher/SnoopCatcher and SpyTag/SnoopTag fusion proteins, which inspires building more cascade systems at the interface. It provides a new method for facilitating the rapid construction of in vitro immobilized multi-enzyme complexes from crude cell lysate. [ABSTRACT FROM AUTHOR]

[Display omitted] Starvation therapy has shown promise as a cancer treatment, but its efficacy is often limited when used alone. In this work, a multifunctional nanoscale cascade enzyme system, named CaCO 3 @MnO 2 -NH 2 @GOx@PVP (CMGP), was fabricated for enhanced starvation/chemodynamic combination cancer therapy. CMGP is composed of CaCO 3 nanoparticles wrapped in a MnO 2 shell, with glucose oxidase (GOx) adsorbed and modified with polyvinylpyrrolidone (PVP). MnO 2 decomposes H 2 O 2 in cancer cells into O 2 , which enhances the efficiency of GOx-mediated starvation therapy. CaCO 3 can be decomposed in the acidic cancer cell environment, causing Ca2+ overload in cancer cells and inhibiting mitochondrial metabolism. This synergizes with GOx to achieve more efficient starvation therapy. Additionally, the H 2 O 2 and gluconic acid produced during glucose consumption by GOx are utilized by MnO 2 with catalase-like activity to enhance O 2 production and Mn2+ release. This process accelerates glucose consumption, reactive oxygen species (ROS) generation, and CaCO 3 decomposition, promoting the Ca2+ release. CMGP can alleviate tumor hypoxia by cycling the enzymatic cascade reaction, which increases enzyme activity and combines with Ca2+ overload to achieve enhanced combined starvation/chemodynamic therapy. In vitro and in vivo studies demonstrate that CMGP has effective anticancer abilities and good biosafety. It represents a new strategy with great potential for combined cancer therapy. [ABSTRACT FROM AUTHOR]

[Display omitted] Reactive oxygen species (ROS)-centered chemodynamic therapy (CDT) holds significant potential for tumor-specific treatment. However, insufficient endogenous H 2 O 2 and extra glutathione within tumor microenvironment (TME) severely deteriorate the CDT's effectiveness. Herein, rich-Zn-Co 3 O 4 / N -doped porous carbon (Zn-Co 3 O 4 /NC) was fabricated by two-step pyrolysis, and applied to build high-efficiency nano-platform for synergistic cancer therapy upon combination with glucose oxidase (GOx), labeled Zn-Co 3 O 4 /NC-GOx for clarity. Specifically, the multiple enzyme-like activities of the Zn-Co 3 O 4 /NC were scrutinously investigated, including peroxidase-like activity to convert H 2 O 2 to O 2 ∙−, catalase-like activity to decompose H 2 O 2 into O 2 , and oxidase-like activity to transform O 2 to O 2 ∙−, which achieved the CDT through the catalytic cascade reaction. Simultaneously, GOx reacted with intracellular glucose to produce gluconic acid and H 2 O 2 , realizing starvation therapy. In the acidic TME, the Zn-Co 3 O 4 /NC-GOx rapidly caused intracellular Zn2+ pool overload and disrupted cellular homeostasis for ion-intervention therapy. Additionally, the Zn-Co 3 O 4 /NC exhibited glutathione peroxidase-like activity, which consumed glutathione in tumor cells and reduced the ROS consumption for ferroptosis. The tumor treatments offer some constructive insights into the nanozyme-mediated catalytic medicine, coupled by avoiding the TME limitations. [ABSTRACT FROM AUTHOR]

[Display omitted] The cancer therapeutic efficacy of the peroxidase (POD)-mimicking nanozyme-based monotherapy is significantly hindered due to insufficient intratumoral hydrogen peroxide (H 2 O 2) and glutathione (GSH) consumption effect on reactive oxygen species (ROS). In this study, we present the development of poly (o -phenylenediamine)@gold nanoparticles (AuNPs) (PoPD@Au) nanocomposites for multifunctional catalytic-photothermal therapy. These nanocomposites exhibit triple distinct nanozymatic activities, i.e. , POD-like activity that catalyzes H 2 O 2 to ROS, glucose oxidase (GOx)-like activity that supplements endogenous H 2 O 2 , and GSH depleting activity that decreases the ROS consumption efficiency. This open source and reduce expenditure strategy for ROS generation allows for the amplification of tumor oxidative stress, thereby enhancing anti-tumor efficiency. Additionally, the PoPD@Au nanocomposites demonstrate outstanding photothermal conversion efficiency, contributing to the synergistic effect between PoPD and AuNPs. Moreover, we reveal the improved photothermal performance of PoPD@Au triggered by the tumor microenvironment pH, which provides additional benefits for targeted catalytic-photothermal therapy. This "four-in-one" design of PoPD@Au enables efficient anti-tumor effects both in vitro and in vivo , making it a universal strategy for engineering catalytic-photothermal therapeutic nanoagents. [ABSTRACT FROM AUTHOR]

Background: Oxidative enzymes targeting lignocellulosic substrates are presently classified into various auxiliary activity (AA) families within the carbohydrate-active enzyme (CAZy) database. Among these, the fungal AA3 glucose–methanol–choline (GMC) oxidoreductases with varying auxiliary activities are attractive sustainable biocatalysts and important for biological function. CAZy AA3 enzymes are further subdivided into four subfamilies, with the large AA3_2 subfamily displaying diverse substrate specificities. However, limited numbers of enzymes in the AA3_2 subfamily are currently biochemically characterized, which limits the homology-based mining of new AA3_2 oxidoreductases. Importantly, novel enzyme activities may be discovered from the uncharacterized parts of this large subfamily. Results: In this study, phylogenetic analyses employing a sequence similarity network (SSN) and maximum likelihood trees were used to cluster AA3_2 sequences. A total of 27 AA3_2 proteins representing different clusters were selected for recombinant production. Among them, seven new AA3_2 oxidoreductases were successfully produced, purified, and characterized. These enzymes included two glucose dehydrogenases (TaGdhA and McGdhA), one glucose oxidase (ApGoxA), one aryl alcohol oxidase (PsAaoA), two aryl alcohol dehydrogenases (AsAadhA and AsAadhB), and one novel oligosaccharide (gentiobiose) dehydrogenase (KiOdhA). Notably, two dehydrogenases (TaGdhA and KiOdhA) were found with the ability to utilize phenoxy radicals as an electron acceptor. Interestingly, phenoxy radicals were found to compete with molecular oxygen in aerobic environments when serving as an electron acceptor for two oxidases (ApGoxA and PsAaoA), which sheds light on their versatility. Furthermore, the molecular determinants governing their diverse enzymatic functions were discussed based on the homology model generated by AlphaFold. Conclusions: The phylogenetic analyses and biochemical characterization of AA3_2s provide valuable guidance for future investigation of AA3_2 sequences and proteins. A clear correlation between enzymatic function and SSN clustering was observed. The discovery and biochemical characterization of these new AA3_2 oxidoreductases brings exciting prospects for biotechnological applications and broadens our understanding of their biological functions. [ABSTRACT FROM AUTHOR]

Nanozymes, as artificial enzymes, overcome the low catalytic efficiency, poor stability, and cost-effectiveness of previous artificial enzymes. In this work, vanadium carbide@vanadium oxide (V2C@VOx) nanosheets were synthesized by a one-pot hydrothermal method using V2C as a precursor and H2O2 as an oxidant. The prepared V2C@VOx nanosheets exhibited excellent multi-enzyme activity such as peroxidase-like activity, superoxide dismutase-like activity, and oxidase-like activity. The entire synthetic process of V2C@VOx nanosheets does not need any additional intercalation agent, strong acid, or base. Meanwhile, the synthesized method of nanozymes was simple, time-saving, and environmentally friendly. In particular, based on the multi-enzyme activity of V2C@VOx nanosheets, the nanozymes catalyzed H2O2 and dissolved O2 to oxidize 3′,3,5,5′-tetramethylbenzidine (TMB). Additionally, glucose reacted with glucose oxidase (GOx) to form H2O2 under water bath conditions. Therefore, the colorimetric sensing strategy of glucose was constructed based on the multi-enzyme activity of V2C@VOx nanosheets and the enzymatic reaction of glucose. The detection limit of the sensor was as low as 0.08 μM. Furthermore, the colorimetric method was successfully used to detect glucose in human serum. The sensor exhibited low cost, high stability, and easy construction. Overall, this work proposed a promising strategy based on novel vanadium-based nanozymes with excellent multi-enzyme activity for biomedical detection. [ABSTRACT FROM AUTHOR]

Wearable glucose biosensors enable noninvasive glucose monitoring, thereby enhancing blood glucose management. In this work, we present a wearable biosensor based on carbon black nanoparticles (CBNPs) for glucose detection in human sweat. The biosensor consists of CBNPs, Prussian blue (PB), glucose oxidase, chitosan, and Nafion. The fabricated biosensor has a linear range of 5 µM to 1250 µM, sensitivity of 14.64 µA mM−1 cm−2, and a low detection potential (−0.05 V, vs. Ag/AgCl). The detection limit for glucose was calculated as 4.83 µM. This reusable biosensor has good selectivity and stability and exhibits a good response to glucose in real sweat. These results demonstrate the potential of our CBNP-based biosensor for monitoring blood glucose in human sweat. [ABSTRACT FROM AUTHOR]

We describe the creation of a conductive microcavity based on the assembly of two pieces of carbon nanotube buckypaper for the entrapment of two enzymes, horseradish peroxidase (HRP) and glucose oxidase (GOx), as well as a redox mediator: 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid diammonium salt (ABTS). The hollow electrode, employing GOx, HRP, and the mediator, as an electrochemical enzyme cascade model, is utilized for glucose sensing at a potential of 50 mV vs. Ag/AgCl. This bienzyme electrode demonstrates the ability to oxidize glucose by GOx and subsequently convert H2O2 to water via the electrical wiring of HRP by ABTS. Different redox mediators (ABTS, potassium hexacyanoferrate (III), and hydroquinone) are tested for HRP wiring, with ABTS being the best candidate for the electroenzymatic reduction of H2O2. To demonstrate the possibility to optimize the enzyme cascade configuration, the enzyme ratio is studied with 1 mg HRP combined with variable amounts of GOx (1–4 mg) and 2 mg GOx combined with variable amounts of HRP (0.5–2 mg). The bienzyme electrode shows continuous operational stability for over a week and an excellent storage stability in phosphate buffer, with a decay of catalytic current by only 29% for 1 mM glucose after 100 days. [ABSTRACT FROM AUTHOR]

Background: Aspergillus niger ATCC 20611 is an industrially important fructooligosaccharides (FOS) producer since it produces the β-fructofuranosidase with superior transglycosylation activity, which is responsible for the conversion of sucrose to FOS accompanied by the by-product (glucose) generation. This study aims to consume glucose to enhance the content of FOS by heterologously expressing glucose oxidase and peroxidase in engineered A. niger. Results: Glucose oxidase was successfully expressed and co-localized with β-fructofuranosidase in mycelia. These mycelia were applied to synthesis of FOS, which possessed an increased purity of 60.63% from 52.07%. Furthermore, peroxidase was expressed in A. niger and reached 7.70 U/g, which could remove the potential inhibitor of glucose oxidase to facilitate the FOS synthesis. Finally, the glucose oxidase-expressing strain and the peroxidase-expressing strain were jointly used to synthesize FOS, which content achieved 71.00%. Conclusions: This strategy allows for obtaining high-content FOS by the multiple enzymes expressed in the industrial fungus, avoiding additional purification processes used in the production of oligosaccharides. This study not only facilitated the high-purity FOS synthesis, but also demonstrated the potential of A. niger ATCC 20611 as an enzyme-producing cell factory. [ABSTRACT FROM AUTHOR]

A portable voltammetric sensor for toxicity assessment was developed based on a screen‐printed carbon electrode modified with SiO2‐CuO‐glucose oxidase (GOx) film. The method is based on the detection of the metabolic activity of E. coli towards glucose as an indicator systems in the presence of antiseptic drugs as model toxic compounds. CuO particles exhibited catalytic activity toward hydrogen peroxide produced by the GOx‐induced oxidation of glucose. A well‐defined reduction peak was registered at E=−0.50 V (vs. Ag/AgCl). The metabolism of glucose by E. coli resulted in a decrease in analytical signal of glucose with the increasing bacteria content in the range of 0.8×109–5.0×109 CFU mL−1 with a calculated limit of detection (LOD) of 0.59×109 CFU mL−1. To evaluate the effect of antiseptics the biosensor was tested in E. coli solution with chlorhexidine (CHD) or decamethoxine (DMT). A linear dependence of glucose consumption by E. coli solution on the antiseptic concentration was obtained in the range of 3.0–12.0 μg mL−1 for CHG and 1.0–12.0 μg mL−1 for DMT, respectively. The developed third generation biosensor showed satisfactory stability and reproducibility of the analytical response. A modified electrode can be used for at least two months. [ABSTRACT FROM AUTHOR]

Wearable metabolite sensors are often limited by easily denaturable enzymes that only allow short‐duration monitoring. Although encapsulating enzymes in metal–organic frameworks (MOFs) shows promise of long‐term enzyme protection, it is typically accompanied by significantly decreased activity due to increased diffusion barrier, steric hindrance for enzyme‐substrate binding, and poor enzyme‐electronic interface. Herein, the co‐encapsulation of enzymes and ultrasmall arginine‐derived carbon dots (Argdot) into a mesoporous Zeolitic Imidazolate Framework‐8 (mZIF‐8) matrix and the enhancement effect of Argdot on enzyme stability and activity, which consequently improves the electrochemical sensor's long‐term sensitivity are investigated. Specifically, the glucose oxidase (GOx)‐Argdot@mZIF‐8 nanocomposite consistently exhibits 40% higher electrochemical sensitivity compared to control GOx@mZIF‐8, an improvement similarly demonstrated with another model enzyme lactate oxidase (LOx). Furthermore, GOx‐Argdot@mZIF‐8 displays excellent stability, retaining 100% of initial sensitivity over 30 days of repeated testing at 37 °C. A touch‐based glucose sensor prototype is demonstrated as an excellent reusable sensor to monitor finger‐tip sweat glucose levels over one month at room temperature. This enzyme encapsulation strategy is not only useful for developing reusable sweat sensors with long‐term monitoring capability, but also promising to expand the industry use of enzymes under harsh conditions. [ABSTRACT FROM AUTHOR]

Aim. The purpose of our work was to test the effect of cafeteria diet and social isolation on physiological and biochemical indicators of mice. Materials and Methods. Female C57BL/6J mice aged 3 months were randomly sorted into four groups: co-housed control, co-housed cafeteria diet (CD), individually housed control (SI), and individually housed CD (CD SI). The CD comprised chocolate, nuts, crackers, and standard food (2:1 ratio) for 12 weeks. Body mass, food/water intake were monitored. Open field test assessed behavior using ToxTrack software. Blood glucose levels used LipidoCare lipidometer and glucose oxidase strip test. Myeloperoxidase activity measured spectrophotometrically in plasma. Paraoxonase activity evaluated using Tris-HCl, CaCl2, and supernatant mixture at 405 nm. GraphPad Prism 10 analyzed data via one-way ANOVA, Welch’s t-test with Benjamini-Hochberg correction. Results presented as mean ± SEM, with P ≤ 0.05 indicating significance between groups. Results and Discussion. Throughout the experiment, we monitored body mass of mice fed different diets and housed in groups or individually. As we can see in Fig. 1, mice that consumed the cafeteria diet in a group or individually gained body mass more rapidly than mice that fed a standard food. At the same time, mice kept individually gained body mass more intensively than their group counterparts (Fig. 1). During the experiment, we monitored also food consumption and water drinking. Fig. 2, A–B represent average consumption of food and water by mice in different groups. Grouped mice fed CD consumed more food than those fed a standard food (Fig. 2, A). Social isolation led to increase in food intake in both feeding groups, on the standard diet and CD. The cafeteria diet had no impact on group water intake in mice (Fig. 2, B). Socially isolated mice on a standard diet consumed more water than group-fed control mice. However, socially isolated mice on a cafeteria diet drank less water compared to those on a standard diet. Blood glucose levels were higher in all experimental groups compared to group-fed control mice on a standard diet (Fig. 3, C), indicating that both cafeteria diet and social isolation led to elevated blood glucose levels. This suggests increased food consumption in these mice. Grouped mice fed cafeteria diet spent more time in inner zone, than mice in other experimental groups (Fig. 3, A, B). Social isolation in the combination with the standard food did not affect the tested behavior parameters in mice compared with the control mice kept in the group (Fig. 3, A–D). Social isolation in the combination with the cafeteria diet increased locomotor activity of mice compared to other mouse groups, that indicates the development depression-like behavior in mice kept individually on cafeteria diet. Additionally, we quantified the protein content and assessed the activities of paraoxonase and myeloperoxidase to glean insights into oxidative stress levels, antioxidant capacity, and inflammatory status. As depicted in Fig. 4, A, discernible disparities were observed between the control group and all other experimental groups, suggestive of potential metabolic dysregulation. Moreover, in Fig. 4, B, a notable distinction was evident between the CD(SI) group and the remaining groups, indicative of heightened stress levels in the mice within this group. Conclusions. Social isolation combined with a standard diet in group-housed mice causes physiological changes similar to those induced by a cafeteria diet, including weight gain, increased food intake, and elevated blood glucose levels. However, only the cafeteria diet, not social isolation, lowers research activity. The combination of social isolation and cafeteria food exacerbates some changes, leading to greater weight gain, food consumption, and depressive behavior. Biochemical analyses revealed differences in oxidative stress, antioxidant capacity, and inflammatory status among experimental groups, with cafeteria diet and socially isolated mice showing distinct patterns indicative of metabolic dysregulation and heightened stress levels compared to control groups. [ABSTRACT FROM AUTHOR]

The purpose of the study was to study the effects of different levels of glucose oxidase on the egg laying performance, immunity and antioxidant capacity of Hyline brown laying hens in the late laying period. 1 000 healthy Hyline brown laying hens were selected and randomly divided into five groups, with 10 replicates per group and 20 hens per replicate. The Hyline brown laying hens in the control group, test group 1, test group 2, test group 3, and test group 4 were fed with 0, 100, 200, 400 and 800 mg/kg of glucose oxidase. The pre-test period was seven days, and the formal test period was 56 days. The results showed that the egg laying rate and average daily egg weight of Hyline brown laying hens in the test group 2, test group 3 and, test group 4 were significantly higher than those in the control group （P<0.05）, and the feed-to-egg ratio was significantly lower than that in the control group and the test group 1 （P<0.05）. The Huff units of eggs in the test group 3 and test group 4 were significantly higher than those in the control group and test group 1 （PcO.05）. The serum levels of immunoglobulin A and immunoglobulin M in the test group 3 and test group 4 were significantly higher than those in the control group and test group 1 （P<0.05）, and the serum levels of immunoglobulin G in the test group 2, test group 3, and test group 4 were significantly higher than those in the control group （JkO.05）. The serum levels of interferon-y, interleukin-2, and interleukin-10 in the test group 2, test group 3, and test group 4 were significantly higher than those in the control group （P<0.05）. The level of tumor necrosis factor-a was significantly lower than that of the control group and the test group 1 （Jk0.05）. The activities of total antioxidant capacity, glutathione peroxidase, and superoxide dismutase in the serum of laying henS in血teSt gr°Up 2, test group 3 and test group 4 were significantly higher than those in the control group （P<0.05）, and the serum activities of superoxide dismutase in the test group 3 and test group 4 were significantly higher than those in the group 1 (P<0.05). The serum malondialdehyde level in all glucose oxidase groups was significantly lower than that in the control group (fk0.05). The study indicates that glucose oxidase can improve egg production performance, immunity, and antioxidant function of laying hens, and the appropriate addition level of glucose oxidase is 400 mg/kg.. [ABSTRACT FROM AUTHOR]

Diabetes has emerged as a global health crisis, with a substantial increase in prevalence and associated healthcare costs. The urgency for early diagnosis to prevent complications has fueled research into advanced biosensing technologies. Plasmonic sensors, leveraging localized surface plasmon resonance (LSPR), have gained prominence for their sensitivity. This study explores a metamaterial-based sensor platform comprising nanospheres fabricated through colloidal lithography. A comprehensive numerical and experimental analysis of the designed metamaterial-based sensor is presented, focusing on the spectral response at the resonance frequency of 535 nm. Finite-difference time-domain (FDTD) simulations reveal the field and charge distributions, enabling a systematic exploration of geometric parameters' impact on absorption resonance. The chosen optimum parameters are validated experimentally, demonstrating excellent agreement between numerical predictions and experimental outcomes. The spectral shifts occurring in the absorption spectrum of the sensor have demonstrated the molecular detection capability of very low concentrations of glucose oxidase, such as 0.001 ppm. Our approach, offering a cost-effective alternative to common fabrication methods, holds promise for the mass production of highly sensitive biosensors, providing a pathway for the development of advanced diagnostic tools for diabetes and other healthcare applications. [ABSTRACT FROM AUTHOR]

The existence of a delicate redox balance in tumors usually leads to cancer treatment failure. Breaking redox homeostasis by amplifying oxidative stress and reducing glutathione (GSH) can accelerate cancer cell death. Herein, we construct a ferroptosis-reinforced nanocatalyst (denoted as HBGL) to amplify intracellular oxidative stress via dual H 2 O 2 production-assisted chemodynamic therapy (CDT). Specifically, a long-circulating liposome is employed to deliver hemin (a natural iron-containing substrate for Fenton reaction and ferroptosis), β -lapachone (a DNA topoisomerase inhibitor with H 2 O 2 generation capacity for chemotherapy), and glucose oxidase (which can consume glucose for starvation therapy and generate H 2 O 2). HBGL can achieve rapid, continuous, and massive H 2 O 2 and •OH production and GSH depletion in cancer cells, resulting in increased intracellular oxidative stress. Additionally, hemin can reinforce the ferroptosis-inducing ability of HBGL, which is reflected in the downregulation of glutathione peroxidase-4 and the accumulation of lipid peroxide. Notably, HBGL can disrupt endo/lysosomes and impair mitochondrial function in cancer cells. HBGL exhibits effective tumor-killing ability without eliciting obvious side effects, indicating its clinical translation potential for synergistic starvation therapy, chemotherapy, ferroptosis therapy, and CDT. Overall, this nanocatalytic liposome may be a promising candidate for achieving potentiated cancer treatment. [Display omitted] • A strategy of breaking cell redox homeostasis is employed. • A dual energy-depletion strategy is introduced. • A nanocatalyst with dual H 2 O 2 self-production ability is constructed. • The strong ferroptosis-inducing capacity and lysosome-disrupting effect are verified. • Combined CDT, ferroptosis, chemotherapy, and starvation therapy are achieved. [ABSTRACT FROM AUTHOR]

Glucose oxidase (GOx)-based enzyme therapeutics are potential alternatives for colorectal cancer (CRC) treatment via glucose consumption and accumulation of hydrogen peroxide (H 2 O 2). Given that H 2 O 2 can be eliminated by cytoprotective autophagy, autophagy inhibitors that can interrupt autolysosome-induced H 2 O 2 elimination are promising combination drugs of GOx. Here, we developed a multifunctional biomimetic nanocarrier for effective co-delivery of an autophagy inhibitor-chloroquine phosphate (CQP) and GOx to exert their synergistic effect by irreversibly upregulating intracellular reactive oxygen species (ROS) levels. Poly (D, l -lactide- co -glycolide) (PLGA) nanoparticles (NPs) were used to encapsulate both GOx and CQP using a W/O/W multi-emulsion method. Calcium phosphate (CaP) was used to "fix" CQP to GOx in the internal water phase, where it served as a pH-sensitive unit to facilitate intracellular drug release. Folic acid-modified red blood cell membranes (FR) were used to camouflage the GOx/CQP/CaP encapsulated PLGA NPs (referred to as PLGA/GCC@FR). In an AOM/DSS-induced CRC mouse model, PLGA/GCC@FR exhibited improved antitumor effects, in which the number of tumor nodes were only a quarter of that in the free drug combination group. The enhanced therapeutic effects of PLGA/GCC@FR were attributed to the prolonged tumor retention which was verified by both dynamic in vivo imaging and drug biodistribution. This multifunctional biomimetic nanocarrier facilitated combined enzyme therapeutics by depleting glucose and augmenting intracellular ROS levels in tumor cells, which exerted a synergistic inhibitory effect on tumor growth. Therefore, this study proposed a novel strategy for the enhancement of combined enzyme therapeutics, which provided a promising method for effective CRC treatment. [Display omitted] • CQP was fixed to GOx via CaP formation to facilitate co-encapsulation by PLGA NPs. • PBA-PEG-FA was inserted on RBCm to realize "right-side-out" coating and CRC targeting. • Glucose consumption and ROS accumulation mediated CRC tumor regression. [ABSTRACT FROM AUTHOR]

Cassava is an important starch crop in the world. Starch factories normally generate a huge amount of cassava root residual which may cause pollution to the environment. In order to find some extra uses for the root cortex, cassava root cortex peroxidase (CCP) is found in quantities up to 20 mg kg−1 in deteriorated cortex tissueand demonstrates some applications similar to horseradish peroxidase (HRP). The major native CCP is a 105‐kDa dimeric peroxidase with two 54‐kDa monomers. CCP is found to be tolerant to a broad pH range from 3 to 11 with maximum activity at pH 5.0 and maintains wide temperature range activity from 20 to 70 °C with an optimum at 65 °C. This indicates CCP to be one of the most robust peroxidases. Despite simple purification with ammonium sulfate precipitation, partial purified CCP is capable of determining glucose concentrations with glucose oxidase similar capability to HRP. For application as a reporter enzyme in immunoassays, the lab‐made secondary antibody conjugated with CCPsuccessfully detects the specific antigen in Western blot analysis using achemiluminescent substrate in the same way as HRP. From the properties and results of trial applications, CCP can be equally replaced in all applications of HRP. The enzyme should be found more potential applications to gain the acceptance. Since raw material for CCP is industrially massive, it should emphasize not only optimization of purification and process cost for industry, but also commercializeto the market. [ABSTRACT FROM AUTHOR]

Although IgG-free immunosensors are in high demand owing to ethical concerns, the development of convenient immunosensors that alternatively integrate recombinantly produced antibody fragments, such as single-chain variable fragments (scFvs), remains challenging. The low affinity of antibody fragments, unlike IgG, caused by monovalent binding to targets often leads to decreased sensitivity. We improved the affinity owing to the bivalent effect by fabricating a bivalent antibody–enzyme complex (AEC) composed of two scFvs and a single glucose dehydrogenase, and developed a rapid and convenient scFv-employed electrochemical detection system for the C-reactive protein (CRP), which is a homopentameric protein biomarker of systemic inflammation. The development of a point-of-care testing (POCT) system is highly desirable; however, no scFv-based CRP-POCT immunosensors have been developed. As expected, the bivalent AEC showed higher affinity than the single scFv and contributed to the high sensitivity of CRP detection. The electrochemical CRP detection using scFv-immobilized magnetic beads and the bivalent AEC as capture and detection antibodies, respectively, was achieved in 20 min without washing steps in human serum and the linear range was 1–10 nM with the limit of detection of 2.9 nM, which has potential to meet the criteria required for POCT application in rapidity, convenience, and hand-held detection devices without employing IgGs. [ABSTRACT FROM AUTHOR]

As a potential tool for combating bacterial infections, chemodynamic therapy (CDT), which utilizes the highly toxic hydroxyl radical (•OH), has shown tremendous promise. Its antibacterial efficacy, however, is compromised by insufficient H 2 O 2 levels and a near-neutral pH at infection sites. Herein, a glucose-fueled and H 2 O 2 self-supplying •OH nanogenerator (GOx-Fe 3 O 4 @MIL) based on cascade catalytic reactions is successfully constructed by immobilizing glucose oxidase (GOx) on the surface of Fe 3 O 4 NPs-encapsulated MIL88B–NH 2. MIL88B–NH 2 (MIL NPs), a peroxidase-mimicking enzyme, immobilizes and protects GOx while synergistically enhancing the CDT effect of Fe 3 O 4 NPs. GOx can continuously convert glucose into gluconic acid and H 2 O 2. The former reduces the pH value to approximately 4, at which point Fe 3 O 4 @ MIL NPs exhibit the highest reaction activity. The continually produced H 2 O 2 is used for subsequent catalysis of activated Fe 3 O 4 @MIL NPs to generate highly toxic •OH for antibacterial applications, avoiding the direct use of relatively high concentrated and toxic H 2 O 2. In vitro and in vivo results indicate that the designed self-activated nanoreactor can significantly inhibit methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant Acinetobacter baumannii (MDR-AB) growth with negligible biotoxicity. [ABSTRACT FROM AUTHOR]

Data represents a compendium of information that perpetually expands with each passing moment, contributed by individuals worldwide. Within the domain of medical science, this reservoir of data accumulates at an almost exponential rate, doubling in volume annually. The emergence of advanced machine learning tools and techniques, subsequent to a substantial evolution in data mining strategies, has bestowed the capacity to glean insights and discern concealed patterns from vast datasets, thus enabling extensive analytical pursuits. This study delves into the application of machine learning algorithms to enhance societal well-being by harnessing the transformative potential of machine learning advancements in the domain of blood glucose concentration estimation through regression analysis. The culmination of this investigation involves establishing a correlation between glucose concentration and hematocrit volume. The dataset employed for this research is sourced from clinically validated electrochemical glucose sensors (commonly referred to as glucose strips). It encompasses diverse levels of both glucose concentration and hematocrit volume, the latter being furnished by an undisclosed source to ensure copyright compliance. This dataset comprises four distinct variables, and the aim of this research involves training the dataset using regression techniques to predict two of these variables. Our results indicate that when utilizing linear regression, the R2 score for GC is approximately 0.916, whereas for HV, it reaches around 0.537. In contrast, employing the support vector regressor yielded R2 scores of about 0.961 for GC and 0.506 for HV. [ABSTRACT FROM AUTHOR]

In this study, glucose oxidase (GOD) was fixed on ferrimagnetic vortex-domain iron oxide nanorings (FVIOs) using the covalent bond crosslinking method to create FVIOs-GOD compounds. The activity of surface-conjugated enzymes can be effectively and selectively enhanced by utilizing FVIOs to induce magnetothermal effects under the influence of alternating magnetic fields. GOD can further catalyze the oxidation of glucose to hydrogen peroxide (H2O2), which possesses bactericidal properties. This study presents a comprehensive technique for controlling the activity of enzymes by nano-magnetothermal stimulation, which was utilized in Escherichia coli antibacterial studies. In comparison to the control group, the enzyme activity of the FVIOs-GOD immobilized enzymes rose by 50 % due to the nano-magnetothermal stimulation, and the enzyme activity could be controlled by varying the magnetic field intensity. The antibacterial experiments indicated that the survival rate of Escherichia coli decreased by 55 % after exposure to a magnetic field. [ABSTRACT FROM AUTHOR]

Modern nanodrug delivery technologies offer new approaches in the fight against cancer. However, due to the heterogeneity of tumors and side effects of anticancer drugs, monotherapies are less effective. Herein, we report a novel pH and light dual‐responsive nanodrug delivery platform. The platform was formed by sulfonate‐modified gold nanoparticles loaded with the anticancer drugs doxorubicin (DOX) and glucose oxidase (GOx) and then covered by water‐soluble pillar[5]arene as a nanovalve. The nanovalve formed by the host‐guest interaction between pillar[5]arene and the sulfonic acid group grafted onto the gold nanoparticle increased the drug loading capacity of the nanoplatform and enabled sustained release of the drug in a simulated weakly acidic tumor environment. The released GOx can consume intracellular glucose, namely, starvation therapy, while the generated hydrogen peroxide can further kill tumor cells, complementing DOX chemotherapy. Gold nanoparticles have good photothermal conversion ability and can enhance the drugs release rate under specific wavelengths of light irradiation. The results of in vitro and in vivo experiments showed that this novel nanodrug delivery platform has good biocompatibility and better therapeutic efficacy relative to monotherapy. This study successfully developed a combined chemo/starvation therapy strategy with good tumor suppression, providing a new approach for cancer treatment. [ABSTRACT FROM AUTHOR]

Diabetes is an important public health problem all over the world that affects the quality of life, and its late diagnosis leads to serious complications such as stroke, blindness, limb amputations, and kidney failure. Fabrication of economical and user‐friendly biosensor systems allows the rapid and early detection of prediabetes and type 2 diabetes. Accordingly, a novel, amino‐functionalized, conjugated, alternating polymer was synthesized, characterized, and coated on a glassy carbon electrode (GCE) to be used as an immobilization platform for the glucose oxidase (GOx) enzyme. The decline in oxygen level due to the enzymatic reaction at a potential of −0.7 V vs. silver/silver chloride (Ag/AgCl) is screened as a biosensor response. The proposed biosensor displayed high selectivity and specificity for glucose with a broad linear range, a low detection limit, good reproducibility and repeatability, and a long shelf life. Surface modifications were characterized using cyclic voltammetry (CV) and field emission scanning electron microscopy (FE‐SEM) techniques. The real‐life sample application of the constructed biosensor to determine the glucose amount was performed in human serum. [ABSTRACT FROM AUTHOR]

Continuous and non‐invasive glucose monitoring and imaging is important for disease diagnosis, treatment, and management. However, glucose monitoring remains a technical challenge owing to the dearth of tissue‐transparent glucose sensors. In this study, we present the development of near‐infrared fluorescent single‐walled carbon nanotube (SWCNT) based nanosensors directly functionalized with glucose oxidase (GOx) capable of immediate and reversible glucose imaging in biological fluids and tissues. We prepared GOx‐SWCNT nanosensors by facile sonication of SWCNT with GOx in a manner that—surprisingly—does not compromise the ability of GOx to detect glucose. Importantly, we find by using denatured GOx that the fluorescence modulation of GOx‐SWCNT is not associated with the catalytic oxidation of glucose but rather triggered by glucose‐GOx binding. Leveraging the unique response mechanism of GOx‐SWCNT nanosensors, we developed catalytically inactive apo‐GOx‐SWCNT that enables both sensitive and reversible glucose imaging, exhibiting a ΔF/F0 of up to 40 % within 1 s of exposure to glucose without consuming the glucose analyte. We finally demonstrate the potential applicability of apo‐GOx‐SWCNT in biomedical applications by glucose quantification in human plasma and glucose imaging in mouse brain slices. [ABSTRACT FROM AUTHOR]