Co-doped cryptomelane-type manganese oxide in situ grown on a nickel foam substrate for high humidity ozone decomposition.

Monolithic catalysts with excellent O3 catalytic decomposition performance were prepared by in situ loading of Co-doped KMn8O16 on the surface of nickel foam. The triple-layer structure with Co-doped KMn8O16/Ni6MnO8/Ni foam was grown spontaneously on the surface of nickel foam by tuning the molar ratio of KMnO4 to Co(NO3)2·6H2O precursors. Importantly, the formed Ni6MnO8 structure between KMn8O16 and nickel foam during in situ synthesis process effectively protected nickel foam from further etching, which significantly enhanced the reaction stability of catalyst. The optimum amount of Co doping in KMn8O16 was available when the molar ratio of Mn to Co species in the precursor solution was 2:1. And the Mn2Co1 catalyst had abundant oxygen vacancies and excellent hydrophobicity, thus creating outstanding O3 decomposition activity. The O3 conversion under dry conditions and relative humidity of 65%, 90% over a period of 5 hr was 100%, 94% and 80% with the space velocity of 28,000 hr-1, respectively. The in situ constructed Co-doped KMn8O16/Ni foam catalyst showed the advantages of low price and gradual applicability of the preparation process, which provided an opportunity for the design of monolithic catalyst for O3 catalytic decomposition.

The potential of Gd doping as a promising approach for enhancing the adsorption properties of nickel-cobalt ferrites.

The study shows that the addition of gadolinium ions has a significant impact on the structure, morphology, and adsorption properties of Ni-Co spinel ferrite that was synthesized by the sol-gel auto-combustion method. The research also indicates that the higher the Gd content, the greater the increase in the lattice parameter, which suggests that Gd3+ ions uniformly replaced the octahedral Fe3+ ions. The morphology and chemical composition of Gd-doped Ni-Co ferrites have been studied using SEM and EDS. Gd adding to the NiCoFe matrix increases the BET surface area by 50% (from 48 to 72 m2/g) and promotes the formation of mesopores with an average radius from 3.9 to 4.9 nm. The pHPZC values of Gd-doped ferrites are in the range of 7.22-7.39, which means that the ferrite surface will acquire a positive charge at natural pH, so this will promote the adsorption of Congo red anionic dye through electrostatic interaction forces. Langmuir, Freundlich, and Dubinin-Radushkevich models were used to explain the mechanism of CR adsorption on the Ni0.5Co0.5GdxFe2-xO4 adsorbent surface. The ionic-covalent parameter has been estimated to describe the surface acid-base properties. Overall, this study highlights the potential of Gd3+ doping as a promising approach for enhancing the adsorption properties of nickel-cobalt ferrites.

Assemblable 3D biomimetic microenvironment for hMSC osteogenic differentiation.

Adequate simulation mimicking a tissue's native environment is one of the elemental premises in tissue engineering. Although various attempts have been made to induce human mesenchymal stem cells (hMSC) into an osteogenic pathway, they are still far from widespread clinical application. Most strategies focus primarily on providing a specific type of cue, inadequately replicating the complexity of the bone microenvironment. An alternative multifunctional platform for hMSC osteogenic differentiation has been produced. It is based on poly(vinylidene fluoride) (PVDF) and cobalt ferrites magnetoelectric microspheres, functionalized with collagen and gelatin, and packed in a 3D arrangement. This platform is capable of performing mechanical stimulation of piezoelectric PVDF, mimicking the bones electromechanical biophysical cues. Surface functionalization with extracellular matrix biomolecules and osteogenic medium complete this all-round approach. hMSC were cultured in osteogenic inducing conditions and tested for proliferation, surface biomarkers, and gene expression to evaluate their osteogenic commitment.

Preparation of 97% pure nickel-cobalt alloy from waste Ni-MH batteries by using waste glass as a fluxing agent.

With the e-waste growing rapidly all over the globe due to growing demand of electronics, smartphones, etc., coming up with an efficient and sustainable recycling process is the need of the hour. The present work reports a novel and sustainable process of manufacturing Ni alloy by bringing together three major waste streams such as waste Ni-MH batteries, e-waste plastics, and waste glass. The chosen temperature (1550 °C) favours the reduction of nickel-oxide by e-waste plastic as the reductant and sends rare earth elements present in the waste Ni-MH battery as oxide mixture to the slag phase. Waste glass powder used in this process functions as the fluxing agent, hence not requiring any additional flux. The reduction mechanism is gas-based, controlled mainly by hydrogen and carbon monoxide gases released as a result of decomposition of e-waste plastic as reaction commenced from cold zone (∼300 °C) to hot zone (1550 °C) in the horizontal tubular furnace. Formation of nickel alloy and enrichment of slag with mixture of rare earth oxides were confirmed by XRD, SEM-EDS, and Rietveld refining analysis performed on the XRD spectra of slag phase. ICP-OES (Inductively coupled plasma optical emission spectroscopy) and LIBS (laser induced breakdown spectrometer KT-100S) confirmed the high metal content in the alloy, thereby emphasizing the purity (∼98%) which is close to the composition of nickel super alloy. A maximum of 61% by weight REO enrichment was achieved in the slag phase, having La2O3:44.6%, Pr2O3:14.8%, and Nd2O3: 1.6% under optimised experimental conditions (1550 °C, 15 min, and 20% waste glass powder). This scientific investigation evinces a promising route for efficient utilisation of waste streams emanating from e-waste, thereby devising a sustainable recycling technique and protecting the environment, too.

Revisiting the Iron(II)/Cobalt(II)-Based Homogenous Fenton-like Processes from the Standpoint of Diverse Metal-Oxygen Complexes.

The aqueous FeIV-oxo complex and FeIII-peroxy complex (e.g., ligand-assisted or interfacial FeIII-hydroperoxo intermediates) have been recognized as crucial reactive intermediates for decontamination in iron-based Fenton-like processes. Intermediates with terminal oxo ligands can undergo the oxygen atom exchange process with water molecules, whereas peroxides are unable to induce such exchanges. Therefore, these distinct metal-oxygen complexes can be distinguished based on the above feature. In this study, we identified previously unknown intermediates with a peroxy moiety and cobalt center that were generated during peroxymonosulfate (PMS) activation via aqueous CoII ions under acidic conditions. Results of theoretical calculations and tip-enhanced Raman spectroscopy revealed that the CoII ion tended to coordinate with the PMS anion to form a bidentate complex with a tetrahedral structure. These reactive cobalt intermediates were collectively named the CoII-PMS* complex. Depending on the inherent characteristics of the target contaminants, the CoII-PMS* complex can directly oxidize organic compounds or trigger PMS disproportionation to release hydroxyl radicals and sulfate radicals for collaborative decontamination. This work provides a comparative study between iron- and cobalt-based Fenton-like processes and proposes novel insights from the standpoint of diverse metal-oxygen complexes.

Adsorption of Carbon Dioxide and Nitrogen in Co3(ndc)3(dabco) Metal-Organic Framework.

Metal-organic frameworks (MOFs) are promising materials for processes such as carbon dioxide (CO2) capture or its storage. In this work, the adsorption of CO2 and nitrogen (N2) in Co3(ndc)3(dabco) MOF (ndc: 2,6-naphthalenedicarboxylate; dabco: 1,4-diazabicyclo[2.2.2]octane) is reported for the first time over the temperature range of 273-323 K and up to 35 bar. The adsorption isotherms are successfully described using the Langmuir isotherm model. The heats of adsorption for CO2 and N2, determined through the Clausius-Clapeyron equation, are 20-27 kJ/mol and 10-11 kJ/mol, respectively. The impact of using pressure and/or temperature swings on the CO2 working capacity is evaluated. If a flue gas with 15% CO2 is fed at 6 bar and 303 K and regenerated at 1 bar and 373 K, 1.58 moles of CO2 can be captured per kg of MOF. The analysis of the multicomponent adsorption of typical flue gas streams (15% CO2 balanced with N2), using the ideal adsorbed solution theory (IAST), shows that at 1 bar and 303 K, the CO2/N2 selectivity is 11.5. In summary, this work reports essential data for the design of adsorption-based processes for CO2 capture using a Co3(ndc)3(dabco) MOF, such as pressure swing adsorption (PSA).

Unveiling the mechanism of cysteamine dioxygenase: A combined HPLC-MS assay and metal-substitution approach.

Mammalian cysteamine dioxygenase (ADO), a mononuclear non-heme Fe(II) enzyme with three histidine ligands, plays a key role in cysteamine catabolism and regulation of the N-degron signaling pathway. Despite its importance, the catalytic mechanism of ADO remains elusive. Here, we describe an HPLC-MS assay for characterizing thiol dioxygenase catalytic activities and a metal-substitution approach for mechanistic investigation using human ADO as a model. Two proposed mechanisms for ADO differ in oxygen activation: one involving a high-valent ferryl-oxo intermediate. We hypothesized that substituting iron with a metal that has a disfavored tendency to form high-valent states would discriminate between mechanisms. This chapter details the expression, purification, preparation, and characterization of cobalt-substituted ADO. The new HPLC-MS assay precisely measures enzymatic activity, revealing retained reactivity in the cobalt-substituted enzyme. The results obtained favor the concurrent dioxygen transfer mechanism in ADO. This combined approach provides a powerful tool for studying other non-heme iron thiol oxidizing enzymes.

Reactive Blue MEBF 222 dye and textile wastewater treatment using metal-doped cobalt and nickel perovskites by batch and column adsorption process.

Water contamination is a serious issue that has an impact on the whole globe. In the current work, adsorption technique was used to remove synthetic Reactive Blue MEBF 222 textile dye utilizing Cd-doped Co (Co1 - xCd1.5xFeO3), Zn-doped Co (Co1 - xZn1.5xFeO3), Cr-doped Co (Co1 - xCr1.5xFeO3), Zn-doped Ni (Ni1 - xZn1.5xFeO3), and Cr-doped Ni (Ni1 - xCr1.5xFeO3) perovskites, synthesized by sol-gel auto-combustion approach. According to the findings of batch adsorption studies, maximum adsorption was observed at pH 3 (45.62 mg/g), 0.01 g/50 ml dosage (36.67 mg/g), 60 min (14.31 mg/g), 100 ppm dye concentration (47.41 mg/g), and 308 K (35.96 mg/g) for Co1 - xCd1.5xFeO3; at 3 pH (42.94 mg/g), 0.01 g/50 ml dosage (35.33 mg/g), 60 min (12.88 mg/g), 100 ppm dye concentration (40.52 mg/g), and 308 K (31.31 mg/g) for Co1 - xZn1.5xFeO3; at 2 pH (38.82 mg/g), 0.01 g/50 ml dosage (32.20 mg/g), 60 min (11.98 mg/g), 100 ppm dye concentration (33.54 mg/g), and 308 K (29.34 mg/g) for Co1 - xCr1.5xFeO3; at 2 pH (34.97 mg/g), 0.01 g/50 ml dosage (30.41 mg/g), 60 min (10.46 mg/g), 100 ppm dye concentration (27.19 mg/g), and 308 K (26.12 mg/g) for Ni1 - xZn1.5xFeO3; and at 2 pH (31.22 mg/g), 0.01 g/50 ml dosage (25.04 mg/g), 60 min (9.48 mg/g), 100 ppm dye concentration (21.73 mg/g), and 308 K (23.61 mg/g) for Ni1 - xCr1.5xFeO3. The pseudo-second-order model showed good fitness for adsorption kinetic data. Electrolytes, detergents/surfactants, and heavy metal ions had a substantial impact on the adsorption potential. The column adsorption experiments demonstrated optimal bed height, flow rate, and intake dye concentration to be 3 cm, 1.8 ml/min, and 70 mg/l, respectively, in the column experiment. With an adsorption capacity of 44.1 mg/g, reactive blue (RB) 222 dye was able to achieve its maximum adsorption. Detailed desorption of RB 222 dye was also achieved. The novelty of this adsorption method lies in its eco-friendliness, ease of handling, and cost-effectiveness.

Protein-driven interaction enhanced electrochemiluminescence biosensor of hydrogen-bonded biohybrid organic frameworks for sensitive immunoassay of disease markers.

The oriented design of reticular materials as emitters can significantly enhance the sensitivity of electrochemiluminescence (ECL) sensing analysis for disease markers. However, due to the structural fragility of hydrogen bonds, relational research on hydrogen-bonded organic frameworks (HOFs) has not been thoroughly conducted. Additionally, the modulation of luminescence behavior through HOFs has been rarely reported. In view of this, hydrogen-bonded biohybrid organic frameworks (HBOFs) were synthesized and recruited for ECL immunoassay applications. HBOFs was easily prepared using 6,6',6″,6‴-(pyrene-1,3,6,8-tetrayl)tetrakis(2-naphthoic acid) as linkers via bovine serum albumin (BSA) activated hydrogen-bonded cross-linking. The material exhibited good fluorescence emission characteristics. And the highly ordered topological structure and molecular motion limitation mediated by BSA overcome aggregation-caused quenching and generate strong aggregation induced emission, expressing hydrogen-bond interaction enhanced ECL (HIE-ECL) activity with the participation of tri-n-propylamine. Furthermore, a sandwich immunosensor was constructed employing cobalt-based metal-phenolic network (CMPN) coated ferrocene nanoparticles (FNPs) as quenchers (CMPN@FNPs). Signal closure can be achieved by annihilating the excited state through electron transfer from both CMPN and FNPs. Using a universal disease marker, carcinoembryonic antigen, as the analysis model, the signal-off sensor obtained a detection limit of 0.47 pg/mL within the detection range of 1 pg/mL - 50 ng/mL. The synthesis and application of highly stable HBOFs triggered by proteins provide a reference for the development of new reticular ECL signal labels, and electron transfer model provides flexible solutions for more sensitive sensing analysis.

An MXene-supported cobalt-MOF nanocomposite-printed electrochemical sensor with high sensitivity for blood creatinine detection in point-of-care settings.

2D MXenes have been used as electrochemical sensor materials, but their output current signal remains weak in point of care (PoC) settings. To address this issue, here we report a novel MXene-supported cobalt-MOF-based nanocomposite, which is used with a carbon black (CB) ink and 3-D printed as the CoMOF-MXene@CB layered electrode structure for the development of a sensor electrode and a PoC chip for electrochemical detection of blood creatinine with an enhanced current range, specificity, and sensitivity. The limit of detection (LOD) and sensitivity of the fabricated sensor were found to be 0.005 µM and 1.1 µA µM-1 cm-2, which are 44 times lower and 32 times enhanced, respectively, as compared to the existing literature report (LOD 0.22 µM and sensitivity 0.034 µA µM-1) for creatinine sensing in PoC settings. The sensor exhibited an excellent linear sensor response ranging from 10 to 800 µM and good reproducibility, stability, and selectivity with significant accuracy. These characteristics helped the sensor to accurately determine the creatinine levels in real human serum samples.

Assessment of an eco-efficient process for the optimization of metal recovery in lithium cobalt oxide and lithium nickel manganese cobalt oxide batteries.

The expansion of technology motivates the increase of global demands for critical minerals. In this context, the exploration of secondary sources of these components is expanding. End-of-life batteries can be seen as potential sources of lithium, cobalt, nickel and manganese for electric vehicles or diverse applications in electronic equipments. This paper provides a comprehensive evaluation of the recovery of metals from waste batteries with diverse chemistry composition. Lithium cobalt oxide (LCO) and lithium nickel cobalt manganese oxide (NMC) batteries were co-treated with polyvinyl chloride (PVC) channels under supercritical water, varying reaction temperature (400-600 °C) and PVC/Battery composition (0-3 m/m) in a tubular continuous reactor. Results show high recovery rates for all metals, with up to 90% percentage recovery of lithium and cobalt in all cases. Temperature and feed composition were identified as determining factors for the recovery of lithium from LCO batteries. In the case of cobalt, temperature was identified as the most important factor that affects its recovery. The selected optimal conditions for cobalt recovery in the solid products of reactions were identified for batteries LCO and NMC: temperature of 600 °C and PVC/Battery ratio of 3.0 and temperature of 500 °C and PVC/Battery ratio of 1.5, respectively. Environmental impacts, primarily Global Warming Potential (GWP), were minimal, with 4.71·10-5 kg CO2 eq., indicating the benefits of the process as an eco-efficient and promising route for the recycling of valuable metals.

A Versatile Visual Molecular Imprinting-Driven Switchable Nanozyme Activity-Based Trimodal Assay and Logic Gate Circuits of Ethyl Carbamate.

Concerns regarding the hazard of the carcinogenic ethyl carbamate (EC) have driven attempts to exploit efficient, timely, straightforward, and economic assays for warning early food safety. Here, we proposed a novel molecularly imprinted polymer Co@MOF-MIP, with a high peroxidase (POD)-like activity and a bright blue fluorescence emission, to develop a versatile visual assay for colorimetric, fluorescent, and photothermal trimodal detection and logic gate outputting of EC. Briefly, the POD-like activity of Co@MOF-MIP made it to decompose H2O2 into ·OH for oxidizing colorless 3,3',5,5'-tetramethylbenzidine (TMB) into a blue oxTMB, resulting in a 660 nm irradiated photothermal effect and bursting the blue fluorescence of Co@MOF-MIP via inner filter effect, observing a decreased fluorescence signal together with an increased colorimetric and 660 nm irradiated photothermal signals. However, EC could specifically fill the imprinted cavities of Co@MOF-MIP to block the catalytic substrates TMB and H2O2 out of Co@MOF-MIP for further reacting with the inside catalytic center of Co2+, resulting in the transformation suppressing of TMB into oxTMB, yielding an EC concentration-dependent trimodal responses in fluorescence signal enhancement, colorimetric, and 660 nm irradiated photothermal signal decreases. Assisted by the portable devices such as smartphones and hand-held thermal imagers, a visual onsite portable trimodal analytical platform was proposed for EC fast and accurate detection with the low detection limits of 1.64, 1.24, and 1.78 µg/L in colorimetric, fluorescent, and photothermal modes, respectively. Interestingly, these reactive events could be programmed by the classical Boolean logic gate analysis to offer a novel promising avenue for the big data Internet of Things monitoring and warning early residual EC in a more intelligent, dynamical, fast, and accurate manner, safeguarding food safety.

A multifunctional N-GO/PtCo nanocomposite bridged carbon fiber interface for the electrochemical aptasensing of CA15-3 oncomarker.

The development of integrated analytical devices is crucial for advancing next-generation point-of-care platforms. Herein, we describe a facile synthesis of a strongly catalytic and durable Nitrogen-doped graphene oxide decorated platinum cobalt (NGO-PtCo) nanocomposite that is conjugated with target-specific DNA aptamer (i-e. MUC1) and grown on carbon fiber. Benefitting from the combined features of the high electrochemical surface area of N-doped GO, high capacitance and stabilization by Co, and high kinetic performance by Pt, a robust, multifunctional, and flexible nanotransducer surface was created. The designed platform was applied for the specific detection of a blood-based oncomarker, CA15-3. The electrochemical characterization proved that nanosurface provides a highly conductive and proficient immobilization support with a strong bio-affinity towards MUC1 aptamer. The specific interaction between CA15-3 and the aptamer alters the surface properties of the aptasensor and the electroactive signal probe generated a remarkable increase in signal intensity. The sensor exhibited a wide dynamic range of 5.0 × 10-2 -200 U mL-1, a low limit of detection (LOD) of 4.1 × 10-2 U mL-1, and good reproducibility. The analysis of spiked serum samples revealed outstanding recoveries of up to 100.03 %, by the proposed aptasensor. The aptasensor design opens new revelations in the reliable detection of tumor biomarkers for timely cancer diagnosis.

Selective removal of iron from sulfuric acid leaching solution of aerospace magnetic material scraps by jarosite process.

Aerospace magnetic material scraps are abundant in cobalt and nickel. Sulfuric acid leaching process is an efficient method for extracting them. But it is a non-selective process, a significant amount of iron dissolves in the solution. This study focuses on the selective removal of iron from this solution using the jarosite process. Eh-pH diagram of K-S-Fe-H2O system was established. Based on thermodynamic analysis, H2O2 is used to oxidize Fe2+ into Fe3+, achieving efficient and selective removal of iron from the solution containing cobalt and nickel. The optimal conditions are as follows: temperature 95°C, K2SO4 dosage coefficient 1.5, seed dosage 10 g/L, time 90 min, pH 1.76, and endpoint pH controlled at approximately 3. Under these conditions, the iron removal efficiency is above 99%, while the loss ratios of cobalt and nickel are below 2%. The product is characterized by XRD and SEM-EDS. Results indicate that the product is jarosite ((K,H3O)Fe3(SO4)2(OH)6), exhibiting an ellipsoid structure with the mean particle size in the range of 0.2-5.0 µm. Temperature, pH value and seed dosage significantly affect reaction rate, particle size and crystallinity, and K2SO4 dosage mainly affects reaction rate and the morphology of jarosite. The jarosite crystallization kinetics can be described by the Avrami equation, with an Avrami index (n) of approximately 2.5 and the apparent activation energy of 42.68 kJ/mol.

Efficient mixed-potential acetone sensor with yttria-stabilized zirconia and porous Co3O4 nanofoam sensing electrode for hazardous gas monitoring and breath analysis.

For hazardous gas monitoring and non-invasive diagnosis of diabetes using breath analysis, porous foams assembled by Co3O4 nanoparticles were designed as sensing electrode materials to fabricate efficient yttria-stabilized zirconia (YSZ)-based acetone sensors. The sensitivity of the sensors was improved by varying the sintering temperature to regulate the morphology. Compared to other materials sintered at different temperatures, the porous Co3O4 nanofoams sintered at 800 °C exhibited the highest electrochemical catalytic activity during the electrochemical test. The response of the corresponding Co3O4-based sensor to 10 ppm acetone was -77.2 mV and it exhibited fast response and recovery times. Moreover, the fabricated sensor achieved a low detection limit of 0.05 ppm and a high sensitivity of -56 mV/decade in the acetone concentration range of 1-20 ppm. The sensor also exhibited excellent repeatability, acceptable selectivity, good O2/humidity resistance, and long-term stability during continuous measurements for over 30 days. Moreover, the fabricated sensor was used to determine the acetone concentration in the exhaled breaths of patients with diabetic ketosis. The results indicated that it could distinguish between healthy individuals and patients with diabetic ketosis, thereby proving its abilities to diagnose and monitor diabetic ketosis. Based on its excellent sensitivity and exhaled breath measurement results, the developed sensor has broad application prospects.

Anti-Proliferative Activity of Poloxamer Cobalt Ferrite Nanoparticles against Human Prostate Cancer (DU-145) Cells: In-Vitro Study.

Prostate cancer is the second most frequent type of cancer death in men. This study refers to the novel hyperthermia application of poloxamer-coated cobalt ferrite as a new approach for thermal eradication of DU-145 human prostate cancerous cells under a radio frequency magnetic field (RF-MF). The hydrothermal method was applied for the synthesis of cobalt ferrite nanoparticles. Then, the structure, size, and morphology of nanoparticle were characterized. The cytotoxicity of the synthesized nanoparticles and RF-MF exposure on DU-145 prostate cancer cells was investigated separately or in combination with colony formation methods and MTT [3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide] assay. Transmission electron microscopy (TEM) confirmed the spherical morphology of nanoparticles with a size of 5.5 ± 2.6 nm. The temperature of cells treated with nanoparticles under RF-MF reached 42.73 ± 0.2°C after 15 min. RF-MF treatment or nanoparticles have not affected cell viability significantly. However, the combination of them eradicated 53% ± 4% of cancerous cells. In-vitro hyperthermia was performed on human prostate cancer cells (DU-145) with cobalt ferrite nanoparticles at specific concentrations that demonstrated a decrease in survival fraction based on colony formation assay compared to cells that were treated alone with nanoparticles or with RF-MF.

Hybrid Organic-Inorganic Copper and Cobalt Complexes for Antimicrobial Potential Applications.

BACKGROUND/AIMS: The naturally occurring phenolic chemical curcumin (CUR), which was derived from the Curcuma longa plant, has a variety of biological actions, including anti-inflammatory, antimicrobial, antioxidant, and anticancer activities. Curcumin is known for its restricted bioavailability due to its hydrophobicity, poor intestinal absorption, and quick metabolism. To boost the biological effects of these bioactive molecules, it is necessary to raise both their bioavailability and their solubility in water. Aim: The aim of this study is to synthesize and characterize hybrid organic-inorganic complexes of copper and cobalt, and to evaluate their antimicrobial potential against a range of pathogenic microorganisms. METHODS: The synthesis of metal curcumin complexes (Cu-CUR and Co-CUR) was achieved by mixing curcumin with copper acetate monohydrate. The solid residue was isolated, filtered, and dried in an oven. X-ray diffraction analysis was used to identify the structure and phase of the prepared samples. FTIR spectra were recorded using a Shimadzu 2200 module. The antimicrobial activity of the prepared complexes was evaluated against four bacterial strains and two Candida species. The chemical materials were dissolved in DMSO to a final concentration of 20%, and the plates were incubated at 37°C for 24 hours. The results showed that the prepared complexes had antimicrobial activity against the tested microorganisms. RESULTS: The study compared the Powder X-ray diffraction (XRD) patterns of prepared copper and cobalt complexes to pure curcumin, revealing new, isostructural complexes. The FTIR analysis showed that the Cu-CUR and Co-CUR complexes varied in their inhibitory effect against microorganisms, with Co-CUR being more effective. The results are consistent with previous studies showing the cobalt-curcumin complex was effective against various bacterial genera, with inhibition activity varying depending on the species and strains of microorganisms. CONCLUSION: Copper and cobalt curcumin complexes, synthesized at room temperature, exhibit high crystallinity and antimicrobial activity. Co-CUR, with its superior antibacterial potential, outperforms pure curcumin in inhibiting microbes. Further investigation is needed to understand their interaction mechanisms with bacteria and fungi.

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

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

Gold Nanodots-Anchored Cobalt Ferrite Nanoflowers as Versatile Tumor Microenvironment Modulators for Reinforced Redox Dyshomeostasis.

Given that tumor microenvironment (TME) exerts adverse impact on the therapeutic response and clinical outcome, robust TME modulators may significantly improve the curative effect and increase survival benefits of cancer patients. Here, Au nanodots-anchored CoFe2O4 nanoflowers with PEGylation (CFAP) are developed to respond to TME cues, aiming to exacerbate redox dyshomeostasis for efficacious antineoplastic therapy under ultrasound (US) irradiation. After uptake by tumor cells, CFAP with glucose oxidase (GOx)-like activity can facilitate glucose depletion and promote the production of H2O2. Multivalent elements of Co(II)/Co(III) and Fe(II)/Fe(III) in CFAP display strong Fenton-like activity for·OH production from H2O2. On the other hand, energy band structure CFAP is superior for US-actuated 1O2 generation, relying on the enhanced separation and retarded recombination of e-/h+ pairs. In addition, catalase-mimic CFAP can react with cytosolic H2O2 to generate molecular oxygen, which may increase the product yields from O2-consuming reactions, such as glucose oxidation and sonosensitization processes. Besides the massive production of reactive oxygen species, CFAP is also capable of exhausting glutathione to devastate intracellular redox balance. Severe immunogenic cell death and effective inhibition of solid tumor by CFAP demonstrates the clinical potency of such heterogeneous structure and may inspire more relevant designs for disease therapy.

Investigating the effect of ligand structure on the anticancer properties of several new Co(II) complexes of vitaminB3-based phosphoramides.

Nicotinamide, known as Vitamin-B3, has shown promising potential in improving various medical conditions. Carbacylamidophosphates (CAPh) are versatile phosphoramide ligands with a wide range of applications in both biochemistry and chemistry. Herein, to obtain compounds with enhanced anticancer activity and study the effect of the structure on this activity, four new Co(II) complexes of vitaminB3-based CAPh ligands with the formula of CoCl2[3-NC5H4CONHPO(NC5H10)2]2(C1), CoCl2[3-NC5H4CONHPO(NC5H9CH3)2]2(C2), CoCl2[3-NC5H4CONHPO(NC6H12)2]2(C3), and CoCl2[3-NC5H4CONHPO(NC4H10)2]2(C4) were designed and synthesized. FT-IR, UV-Vis, Atomic Absorption (AAS),1H, 13C, and 31PNMR, and Mass spectroscopies beside CHN and Molar conductivity methods were utilized to characterize the synthesized compounds. Using MTT-assay and Flow Cytometry, the anticancer effects of these complexes were studied on three distinct cell lines, including one normal cell line (MCF10A) and two cancer cell lines (MDA-MB-231, MCF-7). Results showed that our ligands could form complexes by coordinating with cobalt, which, not only have a very strong killing effect on cancer cells but also have a higher level of safety for normal cells and are more cost-efficient than Cisplatin. C3 was the most effective complex at inhibiting the growth of MCF-7 and MDA-MB-231 cells which exhibited a remarkable 97.5 % reduction in cancer cell growth and a Selectivity Index up to > 37. This is an impressive 93 and 54 times more selective and safer than commonly used drugs like Cisplatin and Doxorubicin, respectively.Flow Cytometry analysis shows complex-induced breast cancer cell apoptosis.The ligands' amine structure and ring size can directly impact the complexes' anticancer effect and safety for normal cells.