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Background: Efficient monitoring of glucose concentration in the human body necessitates the utilization of electrochemically active sensing materials in nonenzymatic glucose sensors. However, prevailing limitations such as intricate fabrication processes, lower sensitivity, and instability impede their practical application. Herein, ternary Cu-Co-Ni-S sulfides nanoporous network structure was synthesized on carbon fiber paper (CP) by an ultrafast, facile, and controllable technique through on-step cyclic voltammetry, serving as a superior self-supporting catalytic electrode for the high-performance glucose sensor., Results: The direct growth of free-standing Cu-Co-Ni-S on the interconnected three-dimensional (3D) network of CP boosted the active site of the composites, improved ion diffusion kinetics, and significantly promoted the electron transfer rate. The multiple oxidation states and synergistic effects among Co, Ni, Cu, and S further promoted glucose electrooxidation. The well-architected Cu-Co-Ni-S/CP presented exceptional electrocatalytic properties for glucose with satisfied linearity of a broad range from 0.3 to 16,000 μM and high sensitivity of 6829 μA mM - 1 cm - 2 . Furthermore, the novel sensor demonstrated excellent selectivity and storage stability, which could successfully evaluate the glucose levels in human serum. Notably, the novel Cu-Co-Ni-S/CP showed favorable biocompatibility, proving its potential for in vivo glucose monitoring., Conclusion: The proposed 3D hierarchical morphology self-supported electrode sensor, which demonstrates appealing analysis behavior for glucose electrooxidation, holds great promise for the next generation of high-performance glucose sensors., (© 2024. The Author(s).)

In this work, a new chemiluminescence (CL) system of Co-Fe prussian blue analogs nanocubes (Co-Fe PBA NCs) that can catalyze luminol to produce strong CL in the absence of H 2 O 2 was established. Co-Fe PBA NCs have the property of oxidase-like activity, and it can catalyze the generation of active oxygen radicals in a dissolved oxygen system. Since caffeic acid (CA) can remove reactive oxygen species in the system, a sensitive detection method for CA on a paper-based chip was developed. Under the optimal conditions, this method showed a good linear response to CA in the range of 10 - 800 ng mL -1 with a limit of 3 ng mL -1 . The proposed method had been used for the determination of CA in tea samples. The results may open a new avenue for the catalytic property on luminol CL system without extra oxidants.

Developing cost-effective and stable materials for the electrocatalysis of hydrogen evolution reaction (HER) remains challenging. In this study, efficient catalysts for HER were synthesized by integrating the cobalt and molybdenum oxides via electrodeposition, followed by subsequent sulfurization of the as-prepared oxides using chemical vapor deposition (CVD). This methodology allowed the incorporation of both cobalt and molybdenum components into the catalyst in a single step. The as-synthesized CoSx@MoSx/MoOx-based catalysts exhibited excellent hydrogen production performance in acidic media owing to the presence of Co-S and Mo-S bonds in the hybrid structure. Particularly, CoSx@MoSx/MoOx(90@360) and MoSx@CoOx(180@180) displayed the best HER performances with low overpotentials of 80 mV and 150 mV, respectively. The catalysts were highly stable, with their stability preserved for over 1000 cycles with marginal reduction in overall efficiency. Therefore, these findings suggest the potential of CoSx@MoSx/MoOx and MoSx@CoOx composites as ideal candidates for developing low-cost catalysts for electrochemical hydrogen production. [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li-S) batteries appear to be one of the most promising energy-storage devices owing to the unparalleled theoretical specific energy, relatively inexpensive price and abundant resources. Despite these attractive features, the practical performances of sulfur cathode still remain a lot of challenges, such as the electrical insulating nature of S and Li 2 S, huge volume change during cycling, notorious shuttle effect of lithium polysulfide intermediates (LiPSs), sluggish redox kinetics and construction of thick electrodes with high sulfur loading. Here, CoFe 2 O 4 nanoparticles anchored on the carbon nanotube (CNT) paper is proposed as free-standing sulfur host to address the issues. The cross-linking CNT network can serve as conductive matrix and accommodate volume change upon cycling simultaneously. Meanwhile, the CoFe 2 O 4 nanoparticles are capable of effectively anchoring LiPSs to suppress the shuttle effect and accelerating LiPSs conversion to boost redox kinetics. Moreover, the free-standing paper electrode without any binder is conducive to constructing stable cathode with high sulfur loading. In consequence, the well-designed S/CoFe 2 O 4 /CNT paper cathodes deliver impressive electrochemical performance, demonstrating an initial discharge capacity of 755.3 mAh g−1 and remaining a high reversible capacity of 642.6 mAh g−1 after 400 cycles at 2 C with an inconspicuous decay of 0.04% per cycle. The bimetallic oxide CoFe 2 O 4 nanoparticles anchored on the carbon nanotube paper is proposed as free-standing sulfur host with enhanced polysulfide trapping and catalytic effects for advanced Li-S batteries. [Display omitted] • Binder-free host realizes high sulfur loading and energy density for Li-S battery. • CoFe 2 O 4 /CNT paper inhibits the polysulfide shuttling via strong chemical interaction. • CNT-anchored CoFe 2 O 4 catalytically promotes the polysulfide conversion kinetics. • The Li-S battery with S/CoFe 2 O 4 /CNT cathode exhibits enhanced capacity and stability. [ABSTRACT FROM AUTHOR]

A spray method is proposed to improve the catalytic properties of ceramic papers to be used as catalytic filters for removing diesel soot particles. Small particles of Ce and Co oxides, acting as active centers for the combustion of the soot retained by the filter, are efficiently and homogeneously deposited. On the contrary, the application of the conventional drip method results in bigger particles mainly agglomerated at the crossings between the fibers of the ceramic paper. As a result, catalytic papers prepared by the spray method exhibit much higher performance with soot combustion temperatures decreased by ~ 30 °C. [ABSTRACT FROM AUTHOR]

Streptomyces rishiriensis produces at least five closely related antibiotics. Strain selection yielded a culture producing only the most active component, coumermycin A. Hydrolysis of this antibiotic by barium hydroxide yielded both 5-methyl-pyrrole-2-carboxylic acid and pyrrole-2-carboxylic acid, which could be separated by paper chromatography. Coumermycin A was thus shown to be two fractions, designated A(1) and A(2) depending upon the nature of the pyrrole carboxylic acid portion. The addition of cobalt to the fermentation medium at a level as low as 0.01 mug/ml shifted the fermentation exclusively to the production of coumermycin A(1). Other ions were ineffective, except nickel, whose activity could be explained by the presence of contaminating cobalt.

Two quantitative, environment-friendly and easily monitored assays for Ni (II) and Co (III) ions analysis in different lipstick samples collected from 500-Iraqi dinars stores located in Baghdad were introduced. The study was based on the reaction of nickel (II) ions with dimethylglyoxime (DMG) reagent and the reaction of cobalt (III) ions with 1-nitroso-2-naphthol (NN) reagent to produce colored products. The color change was measured by spectrophotometric method at 565 nm and 430 nm for Ni and Co, respectively, with linear calibration graphs in the concentration range 0.25-100 mg L-1 (Ni) and 0.5-100 mg L -1 (Co) and LOD and LOQ of 0.11 mg L-1 and 0.36 mg L-1 (Ni), and 0.15 mg L-1 and 0.49 mg L-1 (Co). The UV/VIS data was compared to the results obtained by a novel microfluidic paper-based analytical device (µPAD) platform offering in-situ and cost-effect assay with a similar calibration graph with LOD and LOQ of 0.21 mg L-1 and 0.70 mg L-1 (Ni), and 0.22 mg L-1 and 0.75 mg L-1 (Co). The analysis of variance (ANOVA) indicated no significant difference between the UV/VIS, µPAD, and standard atomic absorption spectrometry (AAS) assay Ftab= 3.46 is much higher than FStat = 0.13 (Ni) and Ftab= 3.46 is much higher than FStat = 0.02 (Co). Also, a good correlation between results via the three methods was found. Thus, the µPAD platform offers a solid base for providing valuable information outside centralized laboratories. [ABSTRACT FROM AUTHOR]

In this paper, novel synergetic PtNP@Co 3 O 4 hollow nanopolyhedrals with peroxidase-like activities are designed and prepared, which can be used as electrochemical and colorimetric signal labels for the enzyme-free dual-channel homogeneous sensing of prostate-specific antigen. When prostate-specific antigens are present, the aptamer-modified PtNP@Co 3 O 4 hollow nanopolyhedrals and magnetic beads form sandwich structures, which have excellent peroxidase-like activities, because of the synergetic effect of PtNP@Co 3 O 4 hollow nanopolyhedrals. The sandwich structures can be separated from the mixture by the magnetic effect of the magnetic beads and catalyze the redox reactions between H 2 O 2 and TMB, generating quantitative electrochemical and colorimetric responses in homogeneous solution simultaneously. Under the optimized conditions, the linear range of both electrochemical (0.01 to 10 ng/ml) and colorimetric (0.01-15 ng/ml) channels can satisfy the demand of prostate-specific antigen detection in clinic (4 ng/ml), and the electrochemical and colorimetric channels have a low detection limit of 0.0079 ng/ml and 0.01 ng/ml respectively without using natural enzymes. The strategy by using synergetic PtNP@Co 3 O 4 hollow nanopolyhedrals as signal probes provides a promising scheme for developing simple, rapid, reliable, and ultrasensitive dual-channel homogeneous biosensors, which has a great potential as a powerful tool in prostate cancer diagnosis., (© 2021. Springer-Verlag GmbH Germany, part of Springer Nature.)

[Display omitted] • Co and Mo Engineered MOF is prepared for specific and sensitive sensing of As. • Co/Mo MOF is utilized for paper-based and spectroscopic sensing. • The sensor works well for 0.05 ppb to 1000 ppm of As(V). • LOD values of 0.02 and 0.04 ppb for As (V) was achieved by spectroscopic and paper-based sensors, respectively. • The Mo-As interactions is responsible for detection of As(V) ions. As one of the most toxic contaminants, arsenic (As) is well-known for diverse types of adversary effects on the life of living beings. Unfortunately, as the conventional methods of its detection generally suffer from several demerits (e.g., long duration, high cost, and complexity), the engineering of advanced materials could be a solution for the development of next generation sensors. In an effort to validate such proposition, we developed a molybdenum based metal–organic framework (Mo-MOF) by modifying a common form of [(Mo 2 O 6)(4,4′–bpy)] n) as a new sensing platform for As. We have successfully developed and characterized a mixed metal (Co/Mo) MOF for the specific, sensitive, and expeditious detection of As(V) metal ions. The color changing capacity (from purple to blue) of Co/Mo-MOF is found to maintain a good linear relationship with changes in the concentration of As(V) from 0.05 ppb to 1000 ppm. This Mo-based MOF sensor, when bound with spectroscoptic and paper-based methods, offered exceptionally low limits of detection (LOD) for As(V) ions such as 0.02 and 0.04 ppb, respectively. [ABSTRACT FROM AUTHOR]

Constructing nanoscale coordination polymers (CPs) with different micro- or nanoscale morphologies and sizes is crucial for the functionalization of CPs-based heterogeneous catalysts. Herein, surfactant polyvinylpyrrolidone (PVP), surface-supported frameworks (filter paper or Ni foam), and Co-based CPs (1), [Co 2 (pdpa)(py) 4 (H 2 O)] n (H 4 pdpa ​= ​5,5'-(pentane-1,2-diyl)-bis(oxy)diisophthalic; py ​= ​pyridine)) were employed to develop highly ordered micro- or nanoscale CPs, achieving microscale 1a (without surface-supported framework) and nanoscale 1b-c (filter paper and Ni foam as surface-supported frameworks for 1b and 1c , respectively). Furthermore, the catalytic performance of nanoscale 1c with spheric particles for the tandem conversion reactions of aromatic nitriles and diamines into imidazoline or tetrahydropyrimidine frameworks was much more prominent than that of large scale 1 , microscale 1a , and nanoscale 1b because of the easily accessible catalytic active sites in the nanoscale spheric particles, which offered a functionalizable platform for the tandem reactions by minimizing the diffusion distance but did little for their activity. By introducing surfactant and surface-supported frameworks, different morphologies and particle sizes of Co-based CPs with micro- or nanoscale 1a-c were constructed and were used as efficient heterogeneous catalysts to execute tandem conversion reactions. [Display omitted] • A new Co-based CPs was constructed under solvothermal conditions. • Co-based CPs with different morphologies and particle sizes were obtained. • The catalytic performance of all the prepared particles for tandem reactions was conducted. [ABSTRACT FROM AUTHOR]

Clavibacter michiganensis subsp. michiganensis (Cmm) and C. michiganensis subsp. capsici (Cmc) are phytopathogenic bacteria that cause bacterial canker disease in tomatoes and peppers, respectively. Bacterial canker disease poses serious challenges to solanaceous crops, causing significant yield losses and economic costs. Effective management necessitates the development of sustainable control strategies employing nanobiotechnology. In this study, the antibacterial effects of four Aspergillus sojae-mediated nanoformulations, including cobalt oxide nanoparticles (Co 3 O 4 NPs), zinc oxide nanoparticles (ZnO NPs), cobalt ferrite nanoparticles (CoFe 2 O 4 NPs), and CoFe 2 O 4 /functionalized multi-walled carbon nanotube (fMWCNT) bionanocomposite, were evaluated against Cmm and Cmc. The diameters of the zone of inhibition of A. sojae-mediated Co 3 O 4 NPs, ZnO NPs, CoFe 2 O 4 NPs, and CoFe 2 O 4 /fMWCNT bionanocomposite against Cmm and Cmc were 23.60 mm, 22.09 mm, 27.65 mm, 22.51 mm, and 19.33 mm, 17.66 mm, 21.64 mm, 18.77 mm, respectively. The broth microdilution assay was conducted to determine the minimal inhibitory and bactericidal concentrations. The MICs of Co 3 O 4 NPs, ZnO NPs, CoFe 2 O 4 NPs, and CoFe 2 O 4 /fMWCNT bionanocomposite against Cmm were 2.50 mg/mL, 1.25 mg/mL, 2.50 mg/mL, and 2.50 mg/mL, respectively. While, their respective MBCs against Cmm were 5.00 mg/mL, 2.50 mg/mL, 5.00 mg/mL, and 5.00 mg/mL. The respective MICs of Co 3 O 4 NPs, ZnO NPs, CoFe 2 O 4 NPs, and CoFe 2 O 4 /fMWCNT bionanocomposite against Cmc were 2.50 mg/mL, 1.25 mg/mL, 5.00 mg/mL, and 5.00 mg/mL. While, their respective MBCs against Cmc were 5.00 mg/mL, 2.50 mg/mL, 10.00 mg/mL, and 10.00 mg/mL. The morphological and ultrastructural changes of Cmm and Cmc cells were observed using field-emission scanning and transmission electron microscopy before and after treatment with sub-minimal inhibitory concentrations of the nanoformulations. Nanoformulation-treated bacterial cells became deformed and disrupted, displaying pits, deep cavities, and groove-like structures. The cell membrane detached from the bacterial cell wall, electron-dense particles accumulated in the cytoplasm, cellular components disintegrated, and the cells were lysed. Direct physical interactions between the prepared nanoformulations with Cmm and Cmc cells might be the major mechanism for their antibacterial potency. Further research is required for the in vivo application of the mycosynthesized nanoformulations as countermeasures to combat bacterial phytopathogens., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cobalt (Co) and Nickel (Ni) are used nowadays in various industrial applications like lithium-ion batteries, raising concerns about their environmental release and public health threats. Both metals are potentially carcinogenic and may cause neurological and cardiovascular dysfunctions, though underlying toxicity mechanisms have to be further elucidated. This study employs untargeted transcriptomics to analyze downstream cellular effects of individual and combined Co and Ni toxicity in human liver carcinoma cells (HepG2). The results reveal a synergistic effect of Co and Ni, leading to significantly higher number of differentially expressed genes (DEGs) compared to individual exposure. There was a clear enrichment of Nrf2 regulated genes linked to pathways such as glycolysis, iron and glutathione metabolism, and sphingolipid metabolism, confirmed by targeted analysis. Co and Ni exposure alone and combined caused nuclear Nrf2 translocation, while only combined exposure significantly affects iron and glutathione metabolism, evidenced by upregulation of HMOX-1 and iron storage protein FTL. Both metals impact sphingolipid metabolism, increasing dihydroceramide levels and decreasing ceramides, sphingosine and lactosylceramides, along with diacylglycerol accumulation. By combining transcriptomics and analytical methods, this study provides valuable insights into molecular mechanisms of Co and Ni toxicity, paving the way for further understanding of metal stress., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

In today's world, major pollutants, such as cationic dyes and heavy metals, pose a serious threat to human health and the environment. In this study, a novel adsorbent was created through the electrospinning of polyvinyl alcohol/polyacrylic acid (PVA/PAA), incorporated with hexagonal boron nitride (hBN) coated with polydopamine (PDA). The integration of hBN and PDA substantially enhanced the adsorption capacity of the PVA/PAA fibers, making them highly effective in adsorbing cationic dyes such as methylene blue and crystal violet, as well as cobalt (II) ions, from contaminated water. The adsorbents were assessed to understand how their adsorption behavior varies with pH, as well as to examine their adsorption kinetics and isotherms. The results indicate that the PVA/PAA-hBN@PDA adsorbent has maximum adsorption capacities of 1029.57 mg/g, 793.65 mg/g, and 62.46 mg/g for methylene blue, crystal violet, and cobalt (II) ions, respectively. This underscores the superior performance of the PVA/PAA-hBN@PDA adsorbent when compared to both the PVA/PAA and PVA/PAA-hBN adsorbents. The adsorption kinetics adhered to a pseudo-second-order model, indicating chemisorption, whereas the Langmuir model implied a monolayer adsorption. Overall, the findings of this study highlight the efficacy of harnessing the synergistic capabilities of hBN and PDA within the PVA/PAA-hBN@PDA adsorbents, providing an efficient and eco-friendly approach to removing cationic dyes and heavy metals from contaminated water, and thereby contributing to a cleaner and safer environment for all., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Nahid Azizi, Shaghayegh Goudarzi, Reza Eslami reports financial support was provided by Mitacs Canada. Nahid Azizi, Reza Eslami reports financial support was provided by Sensofine Inc. Hadis Zarrin reports financial support was provided by Natural Sciences and Engineering Research Council of Canada. Nahid Azizi, Shaghayegh Goudarzi, Reza Eslami reports financial support was provided by Toronto Metropolitan University Faculty of Engineering & Architectural Science. Nahid Azizi, Shaghayegh Goudarzi, Reza Eslami reports financial support was provided by Toronto Metropolitan University. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

As trace levels of thallium (Tl) in water are lethal to humans and ecosystems, it is essential to exploit advanced technologies for efficient Tl removal. In response to this concern, an innovative composite membrane was developed, incorporating polytetrafluoroethylene (PTFE) and featuring a dual-support system with polydopamine (PDA) and polyethyleneimine (PEI), along with bimetallic Prussian blue analogues (Co@Fe-PBAs) as co-supports. The composite membrane exhibited an exceptional Tl + -adsorption capacity (q m ) of 186.1 mg g -1 when utilized for the treatment of water containing low concentration of Tl + (0.5 mg⋅L -1 ). Transmission electron microscopy displayed the obvious Tl + mapping inside the special hollow Co@Fe-PBAs crystals, demonstrating the deep intercalation of Tl + via ion exchange and diffusion. The Tl + -adsorption capability of the composite membrane was not greatly affected by coexisting Na + , Ca 2+ and Mg 2+ as well as the tricky K + , indicating the excellent anti-interference. Co-doped PBAs enhanced ion exchange and intercalation of the composite membrane with Tl + leading to excellent Tl + removal efficiency. The composite membrane could efficiently remove Tl + from thallium-contaminated river water to meet the USEPA standard. This study provides a cost-effective membrane-based solution for efficient Tl + removal from Tl + -containing wastewater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The hydrogenation of CO 2 to CH 4 has gained considerable interest in terms of sustainable energy and environmental mitigation. In this regard, the present work aims to investigate the adsorptive concentration and CO 2 methanation performance over CoFe and NiFe bimetallic catalysts supported on fumed alumina-silica SA96 support at 170-450 °C and under atmospheric pressure. The catalysts were prepared by wet impregnation method, subjected to calcination and further reduced with hydrogen, and their performance in CO 2 methanation was investigated in a hydrogen-rich 2%CO 2 -55%H 2 -43%He gas mixture. In this study, we describe the crystal and mesoporous structures of the prepared catalysts by in-situ XRD and ex-situ nitrogen adsorption, evaluate the NiFe and CoFe metal surface states before and after catalysis by XPS, visualize the surface morphology by SEM, estimate the catalytic activity by gas chromatography, and investigate the adsorbed surface species, showing the presence of *HCOO/*HCO and *CO intermediates, determine two possible pathways of CH 4 formation on the studied catalysts by temperature-programmed desorption mass spectrometry, and correlate the structural and surface properties with high CO 2 conversions up to 100% and methanation selectivities up to 72%. The latter is related to changes in the elemental chemical states and surface composition of CoFe and NiFe nanocatalysts induced by treatment under reaction conditions, and the surface reconstruction during catalysis transfers the part of active 3d transition metals into the pores of the SA96 support. Our thorough characterization study with complementary techniques allowed us to conclude that this high activity is related to the formation of catalytically active Ni/Ni 3 Fe and Co/CoFeO x nanoscale crystallites under H 2 reduction and their maintenance under CO 2 methanation conditions. The successfully applied combination of CO 2 chemisorption and thermodesorption techniques demonstrates the ability to adsorb the CO 2 molecules by supported NiFe and CoFe nanocatalysts and the pure alumina-silica SA96 support., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The utilization of Cobalt (Co) has surged due to it is critical role in renewable energy technologies and other high-tech applications. Concurrently, the potential health risks associated with Co exposure have raised concerns. Previous studies, including our own, have shown that Co can impair learn and memory functions as an epigenetic hazard, even at low concentrations. In this study, we explore the mechanisms of Co-induced ferroptosis in neurodegenerative damage both in vivo and in vitro, focusing on the epigenetic regulation by N6-methyladenosine (m 6 A) demethylase alkB homolog 5 (ALKBH5). We identify heme oxygenase-1 (HO-1) as a direct target gene of ALKBH5, playing a crucial role in mitigating Co-induced ferroptosis. ALKBH5 deficiency affects the post-transcriptional regulation of HO-1 through m 6 A modification, which in turn influences mRNA's stability, intracellular distribution, and alternative splicing, thereby enhancing susceptibility to Co-induced ferroptosis. Additionally, we discuss the potential involvement of heterogeneous nuclear ribonucleoprotein M (hnRNPM) in regulating alternative splicing of HO-1 mRNA, potentially mediated by m 6 A modifications. This study provides new epigenetic insights into the post-transcriptional regulatory mechanisms involved in Co-induced ferroptosis and highlights the broader implications of environmental hazards in neurodegenerative damage., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)