Glucose Oxidase Research Articles

An implantable glucose enzymatic biofuel cell integrated with flexible gold-coated carbon foam and carbon thread bioelectrodes grafted inside a living rat

The advent of long-term implants has increased the urgent need for self-powered biomedical devices. Utilize enzymes to expedite the process of biofuel oxidation. These systems frequently make use of glucose oxidase. A possible solution involves glucose biofuel cells powered by the glucose found in physiological fluids. Biocompatible substances like carbon electrode designs help to transport electrons from the biological reactions to the external circuit as efficiently as possible while maximizing surface area. Despite advances in implantable electrodes, developing miniaturized and flexible electrodes remains challenging. In this work, a metal-coated flexible carbon thread and foam bioelectrode are fabricated and successfully implanted inside a living and freely moving rat. These electrodes are prepared using gold nanostructures as electron enhancers, a negatively charged conducting polymer, a biocompatible redox mediator, and enzymes as biocatalysts. The carbon foam-based enzymatic biofuel cell produces in vitro and in vivo settings, generates a power density of 165 µW/cm2 and 285 µW/cm2, and the carbon thread-based fuel cell produces a power density of 98 µW/cm2 and 180 µW/cm2 in vitro and in vivo environments, respectively. This work paves the way for the possible use of inexpensive electrodes for subdermal implantable microsystems.

Anion Bridged One‐Dimensional Copper‐Based Metal Organic Frameworks as Peroxidase Mimics for Glucose Detection in Apple Fruits

ABSTRACTEnzyme mimics attract wide attentions as detection sensors. However, the widespread application is limited by low efficiency and high cost. Herein, two novel enzyme mimics 1 and 2 were developed with peroxidase‐like activities. The chain‐like structure of 1 exhibited better stability, energy transformation efficiency, and catalytic property than 2. Both of them could generate •OH radicals to oxide chromogenic agents, realizing the colorimetric detection of H2O2. Additionally, under the synergy of glucose oxidase, a cascade strategy for detection of glucose was constructed. This method exhibited excellent selectivity, anti‐interference, and storage performance, as well as a wide linear range (1–60 μM) at pH = 7.4, with the low detection limits of 0.095 and 0.061 μM for 1 and 2, respectively. Furthermore, the strategy was applied for detecting glucose in apple fruit samples. This work overcomes the shortcomings of current enzyme mimics and paves the way for bioanalysis and agricultural applications.

Aptamer proximal enzyme cascade reactions for ultrafast detection of glucose in human blood serum.

Aninnovative colorimetric sensing strategy was developedfor the detection of glucose by the integration of glucose aptamer, glucose oxidase (GOx), and horseradish peroxidase (HRP), termed aptamer proximal enzyme cascade reactions (APECR). In the presence of glucose, aptamer binding enables GOx to catalyze glucose oxidation into H2O2 efficiently. Subsequently, the adjacent HRP catalyzes the oxidation of the peroxidase substrate, 2,2'-biazobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS2-), utilizing the generated H2O2, resulting in a distinct color change. In comparison to the free enzymes and the HRP-GOx system, APECR exhibited higher colorimetric signal. This approach achieved glucose detection within three minutes, which was significantly faster than previous methods. This method showed good sensitivity and selectivity with a limit of detection of 0.013mM. Moreover, the practical utility of this strategy was verified by achieving rapid detection of glucose in clinical serum samples. Hence, the developed strategy has the advantages of simple operation and rapid analysis time for the detection of glucose in human serum.

Fabrication of Compartmentalized Multienzyme Reactor for Colorimetric Biosensing of Glucose and Phenol with High Sensitivity.

Enzymatic cascade reactions are widely utilized in food security, environmental monitoring, and disease diagnostics, whereas their practical application was hindered due to their limited catalytic efficiency and intrinsic fragility to environmental influences. Herein, a compartmentalized dual-enzyme cascade nanoreactor was constructed in metal-organic frameworks (ZIF-8) by a shell-by-shell growth method. ZIF-8 provided a good microenvironment to maintain the activity of enzymes and protected them against harsh conditions. Importantly, experimental results revealed that the encapsulation order and enzyme ratio affected the cascade catalytic activity. When the cascade enzyme ratio was 1:1 and horseradish peroxidase (HRP) was encapsulated in the inner layer with glucose oxidase (GOx) in the outer layer (H@ZIF-8@G@ZIF-8), the nanoreactor facilitated the mass transfer process of substrates and showed the highest cascade catalytic efficiency. The maximum reaction rate (Vmax) of H@ZIF-8@G@ZIF-8 was 294.96 nM s-1, which was 1.6 times greater than G@ZIF-8@H@ZIF-8 (182.84 nM s-1). Therefore, H@ZIF-8@G@ZIF-8 was effectively applied in glucose monitoring and phenol sensing. The glucose biosensor showed a low detection limit of 0.76 μM and a broad linear range of 5-300 μM. The phenol biosensor demonstrated a wide linear range (20-300 μM) with a detection limit of 0.60 μM. In addition, the spiked recovery experiments for glucose and phenol were carried out in serum (recovery: 95.26-100.04%) and tap water (recovery: 97.05-106.50%), respectively. The high accuracy demonstrated potential applications of the cascade system in biosensing and environmental detection.

A pH/GSH Dual-Responsive Triple Synergistic Bimetallic Nanocatalyst for Enhanced Tumor Chemodynamic Therapy.

Chemodynamic therapy (CDT) has garnered significant attention in the field of tumor therapy due to its ability to convert overexpressed hydrogen peroxide (H2O2) in tumors into highly toxic hydroxyl radicals(•OH) through metal ion-mediated catalysis. However, the effectiveness of CDT is hindered by low catalyst efficiency, insufficient intra-tumor H2O2 level, and excessive glutathione (GSH). In this study, a pH/GSH dual responsive bimetallic nanocatalytic system (CuFeMOF@GOx@Mem) is developed by modifying red blood cell membranes onto glucose oxidase (GOx)-loaded Fe-Cu bimetallic MOFs, enhancing the efficacy of CDT through a triple-enhanced way by H2O2 self-supply, catalysts self-cycling, and GSH self-elimination. Upon accumulation in tumor tissues facilitated by the red blood cell membrane, the GOx initiates a reaction with glucose to generate H2O2 and gluconic acid in situ. Subsequently, the reduced pH triggers the release of Fe3+ and Cu2+ from CuFeMOF@GOx@Mem, which is immediately turned into Fe2+ and Cu+ by GSH, activating the Fe2+-mediated Fenton reaction. More importantly, Cu+ can also act as an accelerator of Fe3+/Fe2+ conversion, meanwhile, the generated Cu2+ can be further reduced to Cu+ by GSH. Consequently, sustained accumulation of H2O2 and Fe2+ as well as sustained elimination of GSH are achieved simultaneously, providing a unique approach for improving the anti-tumor ability of CDT.

Self-Cascade of ROS/Glucose-Scavenging Immunomodulatory Hydrogels for Programmed Therapeutics of Infected Diabetic Ulcers via Nrf2/NF-κB Pathway.

Diabetic ulcers (DUs) are characterized by a microenvironment with high oxidative stress, high blood glucose levels, and recalcitrant bacterial infections. This microenvironment is accompanied by long-term suppression of endogenous antioxidant systems, which makes their clinical management extremely challenging. To address this issue, a hybridized novel gold-palladium (AuPd) nanoshell of the injectable/injectable hydrogel system UiO/AuPdshells/BNN6/PEG@Gel (UAPsBP@Gel) is developed. The system is capable of acting as a nitric oxide (NO) reactor utilizing synergistic therapy that harnesses NIR-II light-triggered photothermal effects and controlled release of NO gas for synergistic treatment to eradicate biofilm infections at different depths. The AuPd nanoshells exhibits superoxide dismutase (SOD)-, glucose oxidase (GOx)-, and catalase (CAT)-like activities, enabling self-cascade process for scavenging both reactive oxygen species (ROS) and glucose. This activity reshapes the DUs microenvironment, switches on the endogenous antioxidant Nrf2/HO-1 pathway and inhibits the NF-κB pathway, promotes macrophage polarization toward the anti-inflammatory M2 phenotype, and reduces oxidative stress, resulting in efficient immunomodulation. In vitro/in vivo results demonstrate that the UAPsBP@Gel can multifacetedly enhance the epithelial rejuvenation process through wound hemostasis, pro-cellular migration and vascularization. These results highlight that a programmed therapeutic based on UBAPsP@Gel tailored to the different stages of infected DUs can meet complex clinical needs.

A Cerium Oxide Loaded Hyaluronic Acid Nanosystem Remits Glucose Oxidative Stress-Induced Odontoblasts Mitochondrial Apoptosis through Regulation of PGAM5 Pathway.

Diabetes mellitus (DM) induced mitochondrial oxidative stress (OS) can lead to severe injury of dental pulp. The cerium oxide nanoparticles (CNP) have been proven to have excellent antioxidative activity. However, whether CNP can relieve dental pulp damage caused by DM and the underlying mechanisms remain unclear. In this study, we modified ceria with hyaluronic acid to prepare nanoceria with good biocompatibility, water solubility, and stability, namely, HACNP (hyaluronic acid cerium oxide nanoparticles). We demonstrated the protective effect of HACNP on diabetic OS-induced mitochondrial apoptosis in dental pulp-like cells. As far as the mechanism of action was concerned, glucose oxidase (GO) treatment promoted the activation of phosphoglycerate mutase family 5 (PGAM5) leading to mitochondrial abnormalities and apoptosis in an odontoblast-like cell line (mDPC6T). Knockdown or overexpression of PGAM5 further validate these results. Meanwhile, HACNP remitted GO-related toxicity via down-regulating PGAM5 expression, whereas overexpression of PGAM5 abolished the beneficial effect of HACNP. Furthermore, in the constructed animal research model of diabetic pulp injury, we also confirmed that HACNP alleviated apoptosis and mitochondrial injury of dental pulp and decreased the expression level of PGAM5 in diabetic pulp tissue. In conclusion, these results revealed that HACNP played a protective role on diabetes-associated dental pulp injury through targeting the PGAM5-mediated mitochondrial pathway, providing an idea and method for the prevention or treatment of diabetes-induced dental pulp damage.

Rapid, colorimetric and quantitative detection of microcystin-LR using glucose oxidase-modified magnetic beads, CRISPR/Cas12a and recombinase polymerase amplification strategies

Microcystin-LR (MC-LR) is a significant environmental pollutant that presents a substantial risk to public health. The monitoring with simple approaches is essential for the prevention and management of MC-LR. In this study, we present an aptasensor platform utilizing recombinase polymerase amplification (RPA)-CRISPR/Cas12a technology to accurately identify MC-LR. The MC-LR aptamers were attached to magnetic beads (MBs) following combination with cDNA by hybridization, resulting in the formation of the MB aptasensor. Subsequently, glucose oxidase (GOx)-modified MB were synthesized using single-stranded DNA (MB-ssDNA-GOx) in order to induce alterations in color upon exposure to the TMB-glucose system. The colorimetric signal was visible to the naked eye and exhibited a positive correlation with MC-LR concentration. The sensing platform described in this study demonstrated great sensitivity and achieved a limit of detection of 0.1 μg/L. Furthermore, this methodology exhibited exceptional selectivity and favorable recovery rates, hence showcasing its strong suitability for the analysis of actual water samples. Hence, the assay exhibites significant potential for future environmental monitoring.

A Molecularly Imprinted Electrochemical Sensor for Carbendazim Detection Based on Synergy Amplified Effect of Bioelectrocatalysis and Nanocomposites.

The highly selective and sensitive determination of pesticide residues in food is critical for human health protection. Herein, the specific selectivity of molecularly imprinted polymers (MIPs) was proposed to construct an electrochemical sensor for the detection of carbendazim (CBD), one of the famous broad-spectrum fungicides, by combining with the synergistic effect of bioelectrocatalysis and nanocomposites. Gold nanoparticle-reduced graphene oxide (AuNP-rGO) composites were electrodeposited on a polished glassy carbon electrode (GCE). Then the MIP films were electropolymerized on the surface of the nanolayer using CBD as the template molecule and o-phenylenediamine (OPD) as the monomer. The detection sensitivity of CBD on the heterogeneous structure films was greatly amplified by AuNP-rGO composites and the bioelectrochemical oxidation of glucose, which was catalyzed by glucose oxidase (GOD) with the help of mediator in the underlying solution. The developed sensor showed high selectivity, good reproducibility, and excellent stability towards CBD with the linear range from 2.0 × 10-9 to 7.0 × 10-5 M, and the limit of detection (LOD) of 0.68 nM (S/N = 3). The expected system would provide a new idea for the development of simple and sensitive molecularly imprinted electrochemical sensors (MIESs).

A glucose responsive multifunctional hydrogel with antibacterial properties and real-time monitoring for diabetic wound treatment.

The healing of complex diabetic wounds with a hyperglycemic microenvironment and bacterial infection is considered an important clinical issue. In this study, glucose oxidase (GOx) and gold nanoclusters (AuNCs) were encapsulated in quaternary carboxymethyl chitosan (QCMCS)/sodium alginate oxide (OSA) hydrogels and were immersed in tannic acid (TA) solution to achieve antioxidant, antibacterial, pro-angiogenesis, pro-collagen deposition and real-time monitoring functions. In vitro studies showed that TA-QCMCS/OSA@GOx@AuNC hydrogels had inhibition rates of 98.99% and 99.99% against S. aureus and E. coli, respectively, and the survival rate of mouse fibroblasts (L929) was over 95%. In vivo studies showed that TA-QCMCS/OSA@GOx@AuNC hydrogels were 97.28% effective in healing diabetic wounds. In addition, image signals from TA-QCMCS/OSA@GOx@AuNC hydrogels can be collected in real time to accurately obtain glucose concentration values of diabetic wounds and reflect the healing status of diabetic wounds in a timely manner. The results showed that TA-QCMCS/OSA@GOx@AuNC hydrogels provide a novel idea for real-time monitoring of diabetic wound treatment.

Biomimetic co-immobilization of β-glucosidase, glucose oxidase, and horseradish peroxidase to construct a multi-enzyme biosensor for determination of amygdalin

Biomimetic co-immobilization of β-glucosidase, glucose oxidase, and horseradish peroxidase to construct a multi-enzyme biosensor for determination of amygdalin

Dual-functional PCN-242 (Fe2Co) MOF for sensitive bacterial endotoxin detection.

Endotoxin detection is paramount for monitoring bacterial contamination in food, pharmaceuticals, and clinical diagnostics. The limulus amebocyte lysate (LAL) test, which relies on horseshoe crab blood, has long been the gold standard for endotoxin detection. However, the widespread adoption of this method is constrained by ethical concerns and the high costs associated with harvesting endangered species. Although nanozyme-based colorimetric methods present a more cost-effective and straightforward alternative, their application is limited by suboptimal selectivity and sensitivity. In this study, we report the synthesis and rigorous characterization of the bimetallic PCN-242 (Fe2Co) metal-organic framework (MOF), synthesized using 2-amino terephthalic acid and a pre-synthesized [Fe2Co(μ3-O)(CH3COO)6] cluster. Steady-state kinetic analyses revealed that PCN-242 (Fe2Co) MOF exhibits a significantly higher affinity for hydrogen peroxide (H2O2) compared to horseradish peroxidase (HRP) and other iron-based MOFs. The development of a PCN-242 (Fe2Co)-based colorimetric sensor demonstrated a low limit of detection (LOD) of 1.36 μg mL-1 for endotoxins, with excellent selectivity and reproducibility, thereby enabling effective detection of bacterial endotoxins. Recognizing the potential of the PCN-242 (Fe2Co) MOF beyond endotoxin detection, we explored its utility in glucose biosensing. Moreover, incorporating glucose oxidase (GOx) into the PCN-242 (Fe2Co) MOF framework further enhanced its peroxidase-like catalytic activity. This integration enabled sensitive glucose detection, achieving LODs of 4.24 μM for glucose and 2.2 μM for H2O2 within a linear range of 1 to 150 μM. The dual functionality of PCN-242 (Fe2Co) MOF as a peroxidase mimic and biosensor platform highlights its potential for advanced catalytic and diagnostic applications, offering a versatile and ethical alternative to conventional methods.

Probe on the pivotal role of green rust in improving the enzymatic activity and facilitating the formation of 1O2 in Fenton-like process for degradation of 4-chlorophenol

Iron-based materials have demonstrated significant efficacy in catalyzing hydrogen peroxide (H2O2) for the removal of antibiotics from aquatic environments. Green rust (GR), a hybrid valence state iron-based catalyst, was synthesized. By exploiting the catalytic properties of glucose oxidase (GOx) to generate H2O2 from glucose (Glu), a GR-GOx/Glu system for the removal of recalcitrant organic compound 4-chlorophenol (4-CP) was constructed. In terms of pollutant degradation efficiency, an increase of 30% was observed compared to Fe2+/H2O2 system. Utilizing density functional theory (DFT), we calculated the electrostatic potential energy and charge density distribution, demonstrating the existence of active electron transfer between GR and flavin adenine dinucleotide (FAD), which subsequently enhanced the activity of GOx. The enhancement was pivotal for the sustained generation of preferred oxidative species and rapid degradation of pollutants within the system. Furthermore, the acids and H2O2 generated during enzyme catalysis not only neutralized the alkalinity released by the Fenton-like reaction but also promoted the conversion of superoxide radical (·O2-) to singlet oxygen (1O2). Overall, this study elucidates the fundamental motivation underlying the enhancement of enzymatic activity and highlights the critical role of 1O2 within the system, providing valuable insights into the potential mechanisms by which metal hydroxides catalyze the H2O2 process.

Increasing the dual-enzyme cascade biocatalysis efficiency and stability of metal-organic frameworks via one-step coimmobilization for visual detection of glucose.

In biosensing analysis, the activity of enzyme systems is limited by their fragility, and substrates catalyzed by monoenzymes tend to undergo spontaneous decomposition during ineffective mass transfer processes. In this study, we propose a novel strategy to encapsulate the glucose oxidase and horseradish peroxidase (GOx&HRP) cascade catalytic system within the hydrophilic zeolite imidazole framework ZIF-90. By leveraging the specific pore structure of ZIF-90, we effectively immobilized GOx and HRP molecules in their three-dimensional conformations, which improved the catalytic activity of the encapsulated enzymes compared with that of free GOx and HRP in various harsh environments. Additionally, our strategy reduced the occurrence of ineffective mass transfer and enhanced the sensitivity of the biosensor through an enzyme cascade system. When this biosensor was applied to serum samples containing complex biological matrices, the degradation of GOx&HRP by various proteases and the surface adsorption of diverse biomolecules were effectively prevented, thereby generating stable and reliable signals of glucose levels. The sensor shows remarkable sensitivity and selectivity for determining glucose concentrations ranging from 0 to 2.5 μg ml-1, with a detection limit as low as 0.034 μg ml-1. Furthermore, we developed a paper-based colorimetric sensor utilizing GOx&HRP@ZIF-90 integrated with a smartphone platform for the visual detection of blood glucose.

Synergistic Enzybiotic Effect of a Bacteriophage Endolysin and an Engineered Glucose Oxidase Against Listeria

Listeria monocytogenes represents one of the main risks for food safety worldwide. Two enzyme-based antimicrobials (enzybiotics) have been combined in a novel treatment against this pathogenic bacterium, resulting in a powerful synergistic effect. One of the enzymes is an endolysin from Listeria phage vB_LmoS_188 with amidase activity (henceforth A10), and the other is an engineered version of glucose oxidase from Aspergillus niger (GOX). Both enzymes, assayed separately against Listeria innocua, showed antibacterial activity at the appropriate doses. The combination of the two enzybiotics resulted in a synergistic effect with a log reduction in viable cells (log N0/N) of 4, whereas, taken separately, the same dose of A10 and GOX caused only 1.2 and 0.2 log reductions, respectively. Flow cytometry and microscopy analyses revealed that A10 treatment alone induced the aggregation of dead cells. L. monocytogenes showed higher resistance to single treatment with GOX or A10 than L. innocua. However, the synergic combination of A10 and GOX resulted in a high lethality of L. monocytogenes with a log N0/N higher than 5 (below the detection limit in our analysis). Altogether, these results represent a novel efficient and eco-friendly antimicrobial treatment against the most lethal food-borne pathogen.

The comparison of the antioxidant, antibacterial and antiviral potential of Polish fir honeydew and Manuka honeys

The aim of the present study was to compare the antioxidant, antibacterial and antiviral activities of Podkarpackie coniferous honeydew honey and Manuka honey. The quality of tested honey samples (honeydew-12 and Manuka-4) regarding honey standard was evaluated as well as additional indicators (methylglyoxal, total phenolics and HPTLC phenolic profile, antioxidant potential, glucose oxidase activity, and hydrogen peroxide) were compared. Antibacterial potential was analyzed against Gram-positive (S. aureus and B. cereus) and Gram-negative (E. coli and S. enterica) bacteria. Antiviral activity against different RNA (phi6, MS2) and DNA (T7, phiX174) bacteriophages considered as “viral surrogates” was determined. Based on the determined physicochemical parameters the good quality of tested honeys was confirmed, excluding two samples. The content of polyphenolic compounds in honeydew honey ranged from 583.87 to 1102.42 mg of gallic acid/kg and was strongly correlated with the antioxidant properties. Moreover, for samples with the strongest activity these parameters were comparable to Manuka honey. However, the obtained HPTLC polyphenolic profiles were completely different for honeydew than for Manuka honey which exhibited additional bands (Rf = 0.74 and 0.52). Honeydew honeys were characterized by a strong antiviral and antibacterial properties most of all against Gram-positive bacteria. The MICs (minimal inhibitory concentrations) for S. aureus and B. cereus ranged 15–35% and 8–15% for honeydew and Manuka honeys, respectively. The strongest antiviral properties of honeydew honey were demonstrated mainly against RNA bacteriophages (phi6, MS2) which was even higher than for Manuka honey, especially against MS2 virus. The obtained results suggest that Podkarpackie honeydew honey with the controlled glucose oxidase activity may be a natural substance used to combat viral and bacterial diseases.

Enhancing Ferroptosis-Mediated Radiosensitization via Synergistic Disulfidptosis Induction.

Ferroptosis plays an important role in radiotherapy (RT), and the induction of ferroptosis can effectively sensitize radiotherapy. However, the therapeutic efficiency is always affected by ferroptosis resistance, especially SLC7A11 (Solute Carrier Family 7 Member 11)-cystine-cysteine-GSH (glutathione)-GPX4 (glutathione peroxidase 4) pathway-mediated resistance. In this study, tumor-microenvironment self-activated high-Z element-containing nanoferroptosis inducers, PEGylated Fe-Bi-SS metal-organic frameworks (FBSP MOFs), were developed to sensitize RT. Unexpectedly, ferroptosis-resistant SLC7A11 would be self-adaptively upregulated, leading to self-responsive ferroptosis resistance. Since the conversion from SLC7A11-transported cystine to cysteine is highly glucose-dependent, glucose oxidase (GOx) was incorporated in the MOFs, causing the depletion of NADPH (nicotinamide adenine dinucleotide phosphate) to terminate the conversion from cystine to cysteine, relieving the self-adaptive ferroptosis resistance. Excitingly, the accumulation of cystine would synergistically lead to disulfide stress and trigger disulfidptosis, making a new contribution to enhance therapeutic efficiency. Moreover, the hydrogen peroxide produced during glucose oxidation could also cascade-react with the Fenton reaction, therefore enhancing ferropotosis. Both in vitro and in vivo results suggested that therapeutic efficiency of ferroptosis-mediated radiosensitization could be enhanced benefiting from synergistic disulfidptosis induction, indicating that disulfidptosis might be an efficient strategy to relieve ferroptosis resistance and enhance RT efficiency.

Integrated Wearable Flexible Hydrogel Patch Sensing System for the Detection of Physiological Markers.

Conventional wearable flexible sensing systems typically comprise three components: a flexible substrate that contacts the skin, a signal processing module, and a signal output module. These components function relatively independently, resulting in a complex system that lacks sufficient integration. Therefore, developing an integrated wearable flexible sensing system by combining the flexible substrate, the signal processing module, and the signal output module not only enhances performance and comfort, but also reduces manufacturing costs and the risk of failure. Hydrogel substrates are particularly advantageous due to their excellent biocompatibility, flexibility, and encapsulation capabilities. Herein, we designed an integrated wearable flexible sensing system using an agarose hydrogel to encapsulate biological oxidative enzymes (e.g., glucose oxidase (GOx), lactate oxidase, and ethanol oxidase) and silver nanowires-polydopamine (Ag NWs-PB) as the signal processing module and a color-changing TMB probe as the signal output module. Additionally, we incorporated a polydimethylsiloxane-silicon dioxide patch to collect sweat for detecting physiological markers (e.g., glucose, lactate, and ethanol). An example of the application to facilitate visual detection of glucose in sweat was developed by encapsulating GOx as a biological oxidative enzyme in a sensing system. The system provides results within 3.5 min and operates within a linear range of 0.02 to 5.00 mmol/L, achieving a limit of detection of 0.011 mmol/L. This innovation not only presents a more integrated and portable solution for wearable hydrogel systems, but also introduces a new, feasible method for detecting human physiological markers through a straightforward detection process.

Higher Tumor/Organ Accumulation Ratio of Porous Dual Infinite Coordination Polymer Nanocomposites for Efficient Tumor Photothermal-Starvation-Dual Hypoxia Chemo Synergistic Therapy.

To enhance tumor comprehensive therapeutic effect of nanomedicines, an efficient strategy that integrates polydopamine and IR780 photothermal therapy, glucose oxidase (GOx) starvation therapy, Banoxantrone (AQ4N) and Tirapazamine (TPZ) dual hypoxia chemotherapy is developed in chronological order. Higher tumor accumulation of porous dual infinite coordination polymer nanocomposites are designed and prepared to implement this strategy, in which fluorescent dye IR780 doped hypoxic prodrugs AQ4N and TPZ coordinated with Cu(II) as the core, this core is encapsulated by GOx-loaded porous polydopamine coordinated with Fe(III) (Fe-MPDA). These nanocomposites exhibit a particle dimension of 118.5±21.7nm with pore size of 20.1nm (pore volume 0.012cm3 g-1nm-1), facilitating easy accumulation in tumor tissues. Particularly, their ratio of the area under the curve (AUC) of the tumor/organ drug concentration versus time (AUCtumor/AUCorgans) is 1.28. Upon reaching the tumor, the nanocomposites release GOx and Fe-MPDA in initial stage to execute photothermal and starvation therapy, simultaneously enhance the hypoxic level at the tumor site. Then AQ4N and TPZ undergo synergistic chemotherapy in the enhanced hypoxic environment. Animal experiments show a tumor inhibition rate of 100% and a tumor recurrence rate of 0% after 60d, demonstrating their great potential application for tumor treatment.

Hyperglycemia-responsive nitric oxide-releasing biohybrid cryogels with cascade enzyme catalysis for enhanced healing of infected diabetic wounds.

Diabetic wound infections are a frequent complication for diabetic patients, and conventional treatment for combating diabetic wound infections relies on antibiotics. However, the misuse and overuse of antibiotics have led to the emergence of drug-resistant bacteria, making these infections challenging to treat. Thus, there is an urgent need for alternative strategies to effectively manage diabetic wound infections. Herein, we have developed a hyperglycemia-responsive antibacterial cryogel system that can generate and release hydrogen peroxide (H2O2) and nitric oxide (NO). This system involves incorporating glucose oxidase (GO) and L-Arginine (L-Arg: A) into hyaluronic acid aldehyde methacryloyl (HAAMA: H) and gelatin methacryloyl (GelMA: G) hybrid cryogels (GOA@HG). HAAMA facilitated higher loading and longer stability of L-Arg and GO via a Schiff base reaction. In vitro studies demonstrate that GOA@HG cryogels exhibited outstanding breathability, effective exudate management, and excellent hemostasis capabilities. Moreover, this system could consume excess glucose in diabetic wounds and efficiently eliminate bacteria through the cascaded release of H2O2 and NO without causing antibiotic resistance. In vivo studies further reveal that GOA@HG cryogels significantly enhanced the healing of infected diabetic wounds by inhibiting bacterial growth, accelerating blood vessel formation, and promoting collagen deposition. Overall, GOA@HG cryogels displayed remarkable wound dressing properties and synergistic antimicrobial effects owing to glucose-responsive H2O2 and NO release, which could serve as a highly efficient therapeutic strategy for treating infected diabetic wounds.