Designing Mesoporous Prussian Blue@zinc Phosphate Nanoparticles with Hierarchical Pores for Varisized Guest Delivery and Photothermally-Augmented Chemo-Starvation Therapy.

Background: With the rapid development of nanotechnology, constructing a multifunctional nanoplatform that can deliver various therapeutic agents in different departments and respond to endogenous/exogenous stimuli for multimodal synergistic cancer therapy remains a major challenge to address the inherent limitations of chemotherapy. Methods: Herein, we synthesized hollow mesoporous Prussian Blue@zinc phosphate nanoparticles to load glucose oxidase (GOx) and DOX (designed as HMPB-GOx@ZnP-DOX NPs) in the non-identical pore structures of their HMPB core and ZnP shell, respectively, for photothermally augmented chemo-starvation therapy. Results: The ZnP shell coated on the HMPB core, in addition to providing space to load DOX for chemotherapy, could also serve as a gatekeeper to protect GOx from premature leakage and inactivation before reaching the tumor site because of its degradation characteristics under mild acidic conditions. Moreover, the loaded GOx can initiate starvation therapy by catalyzing glucose oxidation while causing an upgradation of acidity and H2O2 levels, which can also be used as forceful endogenous stimuli to trigger smart delivery systems for therapeutic applications. The decrease in pH can improve the pH-sensitivity of drug release, and O2 can be supplied by decomposing H2O2 through the catalase-like activity of HMPBs, which is beneficial for relieving the adverse conditions of anti-tumor activity. In addition, the inner HMPB also acts as a photothermal agent for photothermal therapy and the generated hyperthermia upon laser irradiation can serve as an external stimulus to further promote drug release and enzymatic activities of GOx, thereby enabling a synergetic photothermally enhanced chemo-starvation therapy effect. Importantly, these results indicate that HMPB-GOx@ZnP-DOX NPs can effectively inhibit tumor growth by 80.31% and exhibit no obvious systemic toxicity in mice. Conclusion: HMPB-GOx@ZnP-DOX NPs can be employed as potential theranostic agents that incorporate multiple therapeutic modes to efficiently inhibit tumors.

Investigation of Direct Electron Transfer of Glucose Oxidase on a Graphene-CNT Composite Surface: A Molecular Dynamics Study Based on Electrochemical Experiments.

Graphene and its variants exhibit excellent electrical properties for the construction of enzymatic interfaces. In particular, the direct electron transfer of glucose oxidase on the electrode surface is a very important issue in the development of enzyme-based bioelectrodes. However, the number of studies conducted to assess how pristine graphene forms different interfaces with other carbon materials is insufficient. Enzyme-based electrodes (formed using carbon materials) have been extensively applied because of their low manufacturing costs and easy production techniques. In this study, the characteristics of a single-walled carbon nanotube/graphene-combined enzyme interface are analyzed at the atomic level using molecular dynamics simulations. The morphology of the enzyme was visualized using an elastic network model by performing normal-mode analysis based on electrochemical and microscopic experiments. Single-carbon electrodes exhibited poorer electrical characteristics than those prepared as composites with enzymes. Furthermore, the composite interface exhibited 4.61- and 2.45-fold higher direct electron efficiencies than GOx synthesized with single-carbon nanotubes and graphene, respectively. Based on this study, we propose that pristine graphene has the potential to develop glucose oxidase interfaces and carbon-nanotube-graphene composites for easy fabrication, low cost, and efficient electrode structures for enzyme-based biofuel cells.

Gas Cluster Ion Beam-Assisted Deposition for Fabricating Dry Multilayers Containing Enzyme and Substrate with On-Demand Release.

Gas cluster ion beam (GCIB)-assisted deposition is used to build multilayered protein-based structures. In this process, Ar3000-5000+ clusters bombard and sputter molecules from a reservoir (target) to a collector, an operation that can be sequentially repeated with multiple targets. The process occurs under a vacuum, making it adequate for further sample conservation in the dry state, since many proteins do not have long-term storage stability in the aqueous state. First of all, the stability in time and versatility in terms of molecule selection are demonstrated with the fabrication of peptide multilayers featuring a clear separation. Then, lysozyme and trypsin are used as protein models to show that the activity remaining on the collector after deposition is linearly proportional to the argon ion dose. The energy per atom (E/n) of the Ar clusters is a parameter that was also changed for lysozyme deposition, and its increase negatively affects activity. The intact detection of larger protein molecules by SDS-PAGE gel electrophoresis and a bioassay (trypsin at ≈25 kDa and glucose oxidase (GOx) at ≈80 kDa) is demonstrated. Finally, GOx and horseradish peroxidase, two proteins involved in the same enzymatic cascade, are successively deposited on ß-d-glucose to build an on-demand release material in which the enzymes and the substrate (ß-d-glucose) are combined in a dry trilayer, and the reaction occurs only upon reintroduction in aqueous medium.

Development of cross-linked glucose oxidase integrated Cu-nanoflower electrode for reusable and stable glucose sensing.

The demand for glucose-sensing devices has increased along with the increasing diabetic population. Here, we aimed to construct a system with a glucose oxidase (GOx)-integrated Cu-nanoflower (Cu-NF) as the underlying electrode. This novel system was successfully developed by creating a cross-linked GOx within a Cu-NF matrix, forming a c-GOx@Cu-NF-coated film on a carbon screen-printed electrode (CSPE). A comparison of the stabilities of the cross-linking methods demonstrated enhanced durability, with an activity level of >88 % maintained after approximately 35 days of storage in room temperature buffer. Regarding the ability of the c-GOx@Cu-NF modified CSPE to detect glucose via electrochemical methods, the redox potential gap (ΔE) and peak current increased in the presence of GOx. In comparison to that of glucose, the sensitivity of c-GOx@Cu-NF was approximately 8 times greater than that of GOx@Cu-NF, with a detection limit of 0.649 µM and a linear range of 5-500 µM. It sustained an average relative activity of 80 % over 20 days. After 10 cycles of repeated use, the activity remained above 75 %. In terms of evaluating the electrode's specificity for glucose, the detection rate for individual similar substances was approximately 1 %. The introduction of a crosslinking strategy to Cu-NF, leading to enhanced mechanical stability and conductivity, improved the detection capability. Furthermore, this approach led to increased long-term storage stability and reusability, allowing for specific glucose detection. To our knowledge, this report represents the first demonstration of a c-GOx@Cu-NF system for integrating electrochemical biosensing devices into digital healthcare pathways, offering enhanced sensing accuracy and mechanical stability.

Determination of glucose oxidase activity by tyrosine fluorescence spectrophotometry.

A novel Fe2+/Tyr/H2O2 fluorescence reaction system has been established for the purpose of analyzing glucose oxidase activity. This system involves the catalysis of glucose oxidase on glucose to produce H2O2, which in turn oxidizes tyrosine to a highly fluorescent substance under the catalysis of Fe2+. The fluorescence intensity is subsequently employed to ascertain the enzymatic activity of glucose oxidase. The enzymatic oxidation reaction and tyrosine fluorescence reaction conditions were optimized based on the H2O2 standard curve equation. Direct fluorescence spectrophotometry was used to determine the activity range and detection limit of glucose oxidase, which were found to be 7.00 × 10-5-7.00 × 10-2 U/mL and 3.36 × 10-5 U/mL (Enzyme-like activity is 6.72 × 10-4 U/mL, The enzyme reaction time is 5 min), respectively, with a relative standard deviation of less than 3.2 %. This method has been successfully applied to determine the activity of glucose oxidase in food additives, with a recovery rate ranging from 96.00 % to 102.0 %.

A Glucose Oxidase-Curcumin Composite Nanoreactor for Multimodal Synergistic Cancer Therapy.

Glucose oxidase (GOx) selectively oxidizes ß-d-glucose into gluconic acid and hydrogen peroxide; thus, it has emerged as a promising anticancer agent by tumor starvation and oxidative therapy. Here, we developed a nanoscale platform or "nanoreactor" that incorporates GOx and the bioactive natural product curcumin (CUR) to achieve a multimodal anticancer nanocomposite. The composite nanoreactor was formed by loading CUR in biodegradable polymeric nanoparticles (NPs) of poly(ethylene glycol)-b-poly(ε-caprolactone) (PEG-PCL). Prime-coating of the NPs with an iron(III)-tannic acid complex enabled facile immobilization of GOx on the NP surface. The NPs were monodisperse with a hydrodynamic diameter of 122 nm and a partially negative surface charge. The NPs were also associated with an excellent CUR loading efficiency and sustained release up to 96 h, which was accelerated by surface-immobilized GOx and followed supercase II transport. Viability assays were conducted on two model cancer cell lines, MCF-7 and MDA-MB-231 cells, as well as human dermal fibroblasts as a representative normal cell line. The assays revealed significantly improved potency of CUR in the composite nanoreactor, with up to 6000- and 1280-fold increase in MCF-7 and MDA-MB-231 cells, respectively, and lower toxicity toward normal cells. The NPs were also able to promote intracellular reactive oxygen species (ROS) generation and dissipation of the mitochondrial membrane potential, providing important clues on the mechanism of action of the nanoreactor. Further investigation of caspase-3 activity revealed that the nanoreactor had no effect or inhibited caspase-3 levels, signifying a caspase-independent mechanism of inducing apoptosis. Our findings present a promising nanocarrier platform that combines therapeutic agents with distinct mechanisms of action acting in synergy for more effective cancer therapy.

Colorimetric Glucose Biosensor Based on Chitosan Films and Its Application for Glucose Detection in Beverages Using a Smartphone Application.

Nowadays, biosensors are gaining increasing interest in foods' and beverages' quality control, owing to their economic production, enhanced sensitivity, specificity, and faster analysis. In particular, colorimetric biosensors can be combined with color recognition applications on smartphones for the detection of analytes, rendering the whole procedure more applicable in everyday life. Herein, chitosan (CS) films were prepared with the deep eutectic solvent (DES) choline chloride/urea/glycerol (ChCl:U:Gly). Glucose oxidase (GOx), a widely utilized enzyme in quality control, was immobilized within CS films through glutaraldehyde (GA), leading to the formation of CS/GOx films. The optimized GOx concentration and DES content were determined for the films. Moreover, the effect of the pH and temperature of the glucose oxidation reaction on the enzymatic activity of GOx was studied. The structure, stability, and specificity of the CS/GOx films as well as the Km values of free and immobilized GOx were also determined. Finally, the analytical performance of the films was studied by using both a spectrophotometer and a color recognition application on a smartphone. The results demonstrated that the films were highly accurate, specific to glucose, and stable when stored at 4 °C for 4 weeks and when reused 10 times, without evident activity loss. Furthermore, the films displayed a good linear response range (0.1-0.8 mM) and a good limit of detection (LOD, 33 µM), thus being appropriate for the estimation of glucose concentration in real samples through a smartphone application.

Oxalic Acid Treatment: Short-Term Effects on Enzyme Activities, Vitellogenin Content, and Residual Oxalic Acid Content in House Bees, Apis mellifera L.

Honeybees (Apis mellifera L.) have to face many challenges, including Varroa destructor infestation, associated with viral transmission. Oxalic acid is one of the most common treatments against Varroa. Little is known about the physiological effects of oxalic acid, especially those on honeybees' immune systems. In this study, the short-term effects (0-96 h) of oxalic acid treatment on the immune system components (i.e., glucose oxidase, phenoloxidase, glutathione S-transferase, catalase activities, and vitellogenin contents) of house bees were preliminarily investigated. Oxalic acid contents of bee bodies and haemolymphs were also measured. The results confirm that oxalic acid is constitutively present in bee haemolymphs and its concentration is not affected by treatment. At 6 h after the treatment, a maximum peak of oxalic acid content was detected on bees' bodies, which gradually decreased after that until physiological levels were reached at 48 h. In the immune system, the oxalic acid treatment determined a peak in glucose oxidase activity at 48 h, indicating a potential defence response and an increase in vitellogenin content at 24 h. No significant changes were recorded in phenoloxidase, glutathione S-transferase, and catalase activities. These results suggest a time-dependent response to oxalic acid, with potential immune system activation in treated bees.

The influence of near-infrared carbon dots on the conformational variation and enzymatic activity of glucose oxidase: A multi-spectroscopic and biochemical study with molecular docking.

In recent years, the exceptional biocatalytic properties of glucose oxidase (GOx) have spurred the development of various GOx-functionalized nanocatalysts for cancer diagnosis and treatment. Carbon dots, renowned for their excellent biocompatibility and distinctive fluorescence properties, effectively incorporate GOx. Given the paramount importance of GOx's enzymatic activity in therapeutic efficacy, this study conducts a thorough exploration of the molecular-level binding dynamics between GOx and near-infrared carbon dots (NIR-CDs). Utilizing various spectrometric and molecular simulation techniques, we reveal that NIR-CDs form a ground-state complex with GOx primarily via hydrogen bonds and van der Waals forces, interacting directly with amino acid residues in GOx's active site. This binding leads to conformational change and reduces thermal stability of GOx, slightly inhibiting its enzymatic activity and demonstrating a competitive inhibition effect. In vitro experiments demonstrate that NIR-CDs attenuate the GOx's capacity to produce H2O2 in HeLa cells, mitigating enzyme-induced cytotoxicity and cellular damage. This comprehensive elucidation of the intricate binding mechanisms between NIR-CDs and GOx provides critical insights for the design of NIR-CD-based nanotherapeutic platforms to augment cancer therapy. Such advancements lay the groundwork for innovative and efficacious cancer treatment strategies.

Au nanozyme-based colorimetric sensor array integrates machine learning to identify and discriminate monosaccharides.

As different monosaccharides exhibit different redox characteristics, this paper presented a novel colorimetric sensor array based on the glucose oxidase-like (GOx-like) activity of Au nanoparticles (NPs) for monosaccharides identification. AuNPs can use O2, ABTS+•, or [Ag(NH3)2]+ as an electron acceptor to catalyze the oxidation of monosaccharides in different velocity, resulting in cross-responsive signals. The current sensor array can distinguish between different monosaccharides or their mixtures through linear discriminant analysis (LDA) and hierarchical clustering analysis (HCA). Moreover, the glucose and fructose concentrations can be estimated simultaneously using a neural network regression model based on the sensor array. This method shows potential for monosaccharide detection in industrial, medical, and biological applications.

Blocking the utilization of carbon sources via two pathways to induce tumor starvation for cancer treatment.

Glucose oxidase (GOx) is often used to starvation therapy. However, only consuming glucose cannot completely block the energy metabolism of tumor cells. Lactate can support tumor cell survival in the absence of glucose. Here, we constructed a nanoplatform (Met@HMnO2-GOx/HA) that can deplete glucose while inhibiting the compensatory use of lactate by cells to enhance the effect of tumor starvation therapy. GOx can catalyze glucose into gluconic acid and H2O2, and then HMnO2 catalyzes H2O2 into O2 to compensate for the oxygen consumed by GOx, allowing the reaction to proceed sustainably. Furthermore, metformin (Met) can inhibit the conversion of lactate to pyruvate in a redox-dependent manner and reduce the utilization of lactate by tumor cells. Met@HMnO2-GOx/HA nanoparticles maximize the efficacy of tumor starvation therapy by simultaneously inhibiting cellular utilization of two carbon sources. Therefore, this platform is expected to provide new strategies for tumor treatment.

Biomimetic Exosome-Sheathed Magnetic Mesoporous Anchor with Modification of Glucose Oxidase for Synergistic Targeting and Starving Tumor Cells.

Efficient protection and precise delivery of biomolecules are of critical importance in the intervention and therapy of various diseases. Although diverse specific marker-functionalized drug carriers have been developed rapidly, current approaches still encounter substantial challenges, including strong immunogenicity, limited target availability, and potential side effects. Herein, we developed a biomimetic exosome-sheathed magnetic mesoporous anchor modified with glucose oxidase (MNPs@mSiO2-GOx@EM) to address these challenges and achieve synergistic targeting and starving of tumor cells. The MNPs@mSiO2-GOx@EM anchor integrated the unique characteristics of different components. An external decoration of exosome membrane (EM) with high biocompatibility contributed to increased phagocytosis prevention, prolonged circulation, and enhanced recognition and cellular uptake of loaded particles. An internal coated magnetic mesoporous core with rapid responsiveness by the magnetic field guidance and large surface area facilitated the enrichment of nanoparticles at the specific site and provided enough space for modification of glucose oxidase (GOx). The inclusion of GOx in the middle layer accelerated the energy-depletion process within cells, ultimately leading to the starvation and death of target cells with minimal side effects. With these merits, in vitro study manifested that our nanoplatform not only demonstrated an excellent targeting capability of 94.37% ± 1.3% toward homotypic cells but also revealed a remarkably high catalytical ability and cytotoxicity on tumor cells. Assisted by the magnetic guidance, the utilization of our anchor obviously inhibits the tumor growth in vivo. Together, our study is promising to serve as a versatile method for the highly efficient delivery of various target biomolecules to intended locations due to the fungibility of exosome membranes and provide a potential route for the recognition and starvation of tumor cells.

A Zn-MOF-GOx-based cascade nanoreactor promotes diabetic infected wound healing by NO release and microenvironment regulation.

Diabetic wound healing is a great clinical challenge due to the microenvironment of hyperglycemia and high pH value, bacterial infection and persistent inflammation. Here, we develop a cascade nanoreactor hydrogel (Arg@Zn-MOF-GOx Gel, AZG-Gel) with arginine (Arg) loaded Zinc metal organic framework (Zn-MOF) and glucose oxidase (GOx) based on chondroitin sulfate (CS) and Pluronic (F127) to accelerate diabetic infected wound healing. GOx in AZG-Gel was triggered by hyperglycemic environment to reduce local glucose and pH, and simultaneously produced hydrogen peroxide (H2O2) to enable Arg-to release nitric oxide (NO) for inflammation regulation, providing a suitable microenvironment for wound healing. Zinc ions (Zn2+) released from acid-responsive Zn-MOF significantly inhibited the proliferation and biofilm formation of S.aureus and E.coli. AZG-Gel significantly accelerated diabetic infected wound healing by down-regulating pro-inflammatory tumor necrosis factor (TNF)-α and interleukin (IL)-6, up-regulating anti-inflammatory factor IL-4, promoting angiogenesis and collagen deposition in vivo. Collectively, our nanoreactor cascade strategy combining "endogenous improvement (reducing glucose and pH)" with "exogenous resistance (anti-bacterial and anti-inflammatory)" provides a new idea for promoting diabetic infected wound healing by addressing both symptoms and root causes. STATEMENT OF SIGNIFICANCE: A cascade nanoreactor (AZG-Gel) is constructed to solve three key problems in diabetic wound healing, namely, hyperglycemia and high pH microenvironment, bacterial infection and persistent inflammation. Local glucose and pH levels are reduced by GOx to provide a suitable microenvironment for wound healing. The release of Zn2+ significantly inhibits bacterial proliferation and biofilm formation, and NO reduces wound inflammation and promotes angiogenesis. The pH change when AZG-Gel is applied to wounds is expected to enable the visualization of wound healing to guide the treatment of diabetic wound. Our strategy of "endogenous improvement (reducing glucose and pH)" combined with "exogenous resistance (anti-bacterial and anti-inflammatory)" provides a new way for promoting diabetic wound healing.

Relationships among Hydrogen Peroxide Concentration, Catalase, Glucose Oxidase, and Antimicrobial Activities of Honeys.

Honey is a natural sweetener made by bees that exhibits antimicrobial activity, mainly related to its H2O2 content. The aim of this work was to research the H2O2 concentration of 24 Spanish honeys from different botanical origins, studying their possible correlation with glucose oxidase (GOx), catalase (CAT), and anti-Staphylococcus aureus activities (minimal inhibition concentration (MIC), minimal bactericidal concentration (MBC), and percentage of inhibition at 5% (w/v) honey against Staphylococcus aureus), as well as possible correlations among all the analyzed parameters. The results showed that the H2O2 concentration did not depend on the botanical origin of the honeys. There were neither correlations between the H2O2 concentration and the activities of GOx and CAT, nor between GOx and antimicrobial activity. However, CAT and antimicrobial activities were positively correlated. Therefore, CAT could be successfully used as a possible marker of the antimicrobial activity of honeys against Staphylococcus aureus. Furthermore, a linear regression model has been fitted to explain the antimicrobial activity from CAT and GOx activity and H2O2 concentration. Although H2O2 is one of the compounds involved in honey's antibacterial activity, this capacity also strongly depends on other honey components (such as low water activity, acidity, osmolarity, and phenolic compounds). The very high anti-Staphylococcus aureus activity exhibited by all samples could be interesting for commercial honey-based formulations also helping to promote local beekeeping.

Metal-ligand cross-link strategy engineered iron-doped dopamine-based superstructure as peroxidase-like nanozymes for detection of glucose.

Nanozymes are nanomaterials with mimetic enzyme properties and the related research has attracted much attention. It is of great value to develop methods to construct nanozymes and to study their application in bioanalysis. Herein, the metal-ligand cross-linking strategy was developed to fabricate superstructure nanozymes. This strategy takes advantage of being easy to operate, adjustable, cheap, and universal. The fabricated superstructure nanozymes possess efficient peroxidase-like catalytic activity. The enzyme reaction kinetic tests demonstrated that for TMB and H2O2, the Km is 0.229 and 1.308 mM, respectively. Furthermore, these superstructure nanozymes are applied to highly efficient and sensitive detection of glucose. The linear range for detecting glucose is 20-2000 µM, and the limit of detection is 17.5 µM. Furthermore, mechanistic research illustrated that this integrated system oxidizes glucose to produce hydrogen peroxide and further catalyzes the production of ·OH and O2·-, which results in a chromogenic reaction of oxidized TMB for the detection of glucose. This work could not only contribute to the development of efficient nanozymes but also inspire research in the highly sensitive detection of other biomarkers.

Magnetic Nanoparticle Support with an Ultra-Thin Chitosan Layer Preserves the Catalytic Activity of the Immobilized Glucose Oxidase.

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.

Preparation, Characterization, and Evaluation of Enzyme Co-Modified Fish Gelatin-Based Antibacterial Derivatives.

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.

Enhancing metformin-induced tumor metabolism destruction by glucose oxidase for triple-combination therapy.

Despite decades of laboratory and clinical trials, breast cancer remains the main cause of cancer-related disease burden in women. Considering the metabolism destruction effect of metformin (Met) and cancer cell starvation induced by glucose oxidase (GOx), after their efficient delivery to tumor sites, GOx and Met may consume a large amount of glucose and produce sufficient hydrogen peroxide in situ. Herein, a pH-responsive epigallocatechin gallate (EGCG)-conjugated low-molecular-weight chitosan (LC-EGCG, LE) nanoparticle (Met-GOx/Fe@LE NPs) was constructed. The coordination between iron ions (Fe3+) and EGCG in this nanoplatform can enhance the efficacy of chemodynamic therapy via the Fenton reaction. Met-GOx/Fe@LE NPs allow GOx to retain its enzymatic activity while simultaneously improving its stability. Moreover, this pH-responsive nanoplatform presents controllable drug release behavior. An in vivo biodistribution study showed that the intracranial accumulation of GOx delivered by this nanoplatform was 3.6-fold higher than that of the free drug. The in vivo anticancer results indicated that this metabolism destruction/starvation/chemodynamic triple-combination therapy could induce increased apoptosis/death of tumor cells and reduce their proliferation. This triple-combination therapy approach is promising for efficient and targeted cancer treatment.

A catalytic membrane approach as a way to obtain sweet and unsweet lactose-free milk.

The growing need in the current market for innovative solutions to obtain lactose-free (L-F) milk is caused by the annual increase in the prevalence of lactose intolerance inside as well as the newborn, children, and adults. Various configurations of enzymes can yield two distinct L-F products: sweet (ß-galactosidase) and unsweet (ß-galactosidase and glucose oxidase) L-F milk. In addition, the reduction of sweetness through glucose decomposition should be performed in a one-pot mode with catalase to eliminate product inhibition caused by H2O2. Both L-F products enjoy popularity among a rapidly expanding group of consumers. Although enzyme immobilization techniques are well known in industrial processes, new carriers and economic strategies are still being searched. Polymeric carriers, due to the variety of functional groups and non-toxicity, are attractive propositions for individual and co-immobilization of food enzymes. In the presented work, two strategies (with free and immobilized enzymes; ß-galactosidase NOLA, glucose oxidase from Aspergillus niger, and catalase from Serratia sp.) for obtaining sweet and unsweet L-F milk under low-temperature conditions were proposed. For free enzymes, achieving the critical assumption, lactose hydrolysis and glucose decomposition occurred after 1 and 4.3 h, respectively. The tested catalytic membranes were created on regenerated cellulose and polyamide. In both cases, the time required for lactose and glucose bioconversion was extended compared to free enzymes. However, these preparations could be reused for up to five (ß-galactosidase) and ten cycles (glucose oxidase with catalase).

Glucose Oxidase Energized Osmium with Dual-Active Centers and Triple Enzyme Activities for Infected Diabetic Wound Management.

Diabetic wounds are susceptible to bacterial infections, largely linked to high blood glucose levels (hyperglycemia). To treat such wounds, enzymes like glucose oxidase (GOx) can be combined with nanozymes (nanomaterials mimic enzymes) to use glucose effectively for purposes. However, there is still room for improvement in these systems, particularly in terms of process simplification, enzyme activity regulation, and treatment effects. Herein, the approach utilizes GOx to directly facilitate the biomineralized growth of osmium (Os) nanozyme (GOx-OsNCs), leading to dual-active centers and remarkable triple enzyme activities. Initially, GOx-OsNCs use vicinal dual-active centers, enabling a self-cascaded mechanism that significantly enhances glucose sensing performance compared to step-by-step reactions, surpassing the capabilities of other metal sources such as gold and platinum. In addition, GOx-OsNCs are integrated into a glucose-sensing gel, enabling instantaneous visual feedback. In the treatment of infected diabetic wounds, GOx-OsNCs exhibit multifaceted benefits by lowering blood glucose levels and exhibiting antibacterial properties through the generation of hydroxyl free radicals, thereby expediting healing by fostering a favorable microenvironment. Furthermore, the catalase-like activity of GOx-OsNCs aids in reducing oxidative stress, inflammation, and hypoxia, culminating in improved healing outcomes. Overall, this synergistic enzyme-nanozyme blend is user-friendly and holds considerable promise for diverse applications.