Role Of Cu Research Articles

Exploring the cytotoxicity mechanisms of copper ions and copper oxide nanoparticles in cells from the excretory system

Copper oxide nanoparticles (CuO NPs) are widely applied in various products, including food, cosmetic, biomedical, and environmental goods. Despite their broad use, potential risks are still associated with these NPs, therefore, the aim of this study is to delve deeper into the cytotoxic effects of 85 nm CuO NPs on kidney MDCK and liver AML-12 cells, representing cell models from the excretory system. Our findings pointed out that the viability of both cell lines decreased in a concentration-dependent manner when exposed to CuO NPs. Additionally, CuO NPs induced the overproduction of reactive oxygen species (ROS) and caused depolarization of the mitochondrial membrane, thereby arresting the cell cycle at the G2/M phase in MDCK and AML-12 cells. Importantly, unlike others our study uncovered distinctive forms of cellular death induced by CuO NPs in these cell lines. MDCK cells exhibited a combination of apoptosis and autophagy while early apoptosis was predominant in AML-12 cells. Moreover, the role of Cu2+ ions and CuO NPs in exerting cytotoxic effects was investigated, revealing that MDCK cells were affected by both copper ions and NPs. In contrast, AML-12 cells experienced toxic effects solely from CuO NPs.These findings provide crucial insights into the different cell death mechanisms caused either by CuO NPs or Cu2+ ions in excretory system cells in vitro. Nevertheless, further research is needed to explore the underlying mechanisms at the in vivo level, ensuring the safe use of CuO NPs. The results suggest that specific concentrations of metal oxide NPs can impact the physiology of cells within the excretory system of various mammals, including humans, and pave the way for comparing the toxic effects between ions and nanoparticles for further nanotoxicological studies.

Carnosine, Zinc and Copper: A Menage a Trois in Bone and Cartilage Protection.

Dysregulated metal homeostasis is associated with many pathological conditions, including arthritic diseases. Osteoarthritis and rheumatoid arthritis are the two most prevalent disorders that damage the joints and lead to cartilage and bone destruction. Recent studies show that the levels of zinc (Zn) and copper (Cu) are generally altered in the serum of arthritis patients. Therefore, metal dyshomeostasis may reflect the contribution of these trace elements to the disease's pathogenesis and manifestations, suggesting their potential for prognosis and treatment. Carnosine (Car) also emerged as a biomarker in arthritis and exerts protective and osteogenic effects in arthritic joints. Notably, its zinc(II) complex, polaprezinc, has been recently proposed as a drug-repurposing candidate for bone fracture healing. On these bases, this review article aims to provide an overview of the beneficial roles of Cu and Zn in bone and cartilage health and their potential application in tissue engineering. The effects of Car and polaprezinc in promoting cartilage and bone regeneration are also discussed. We hypothesize that polaprezinc could exchange Zn for Cu, present in the culture media, due to its higher sequestering ability towards Cu. However, future studies should unveil the potential contribution of Cu in the beneficial effects of polaprezinc.

Experimental study and DFT calculation of the role of Cu loaded on activated carbon in desulfurization under dry and moist atmospheres

The reactive adsorption of H2S under different atmospheres is of great significance to protect the staff on site from exposure risks of polluted gases. The Cu0-loaded activated carbon (AC@Cu0) adsorbent was synthesized and characterized, which was used to dynamic adsorption of H2S under ambient temperature and different relative humidity (RH). When RH was 60%, the highest adsorption capacity reached 77.7 mg/g. The desulfurization products comprised element sulfur, sulfide and sulfate by the catalytic oxidation and reactive adsorption of AC@Cu0. In addition to the chemical nature of AC@Cu0, the structural properties (surface area and pore volume) also play a crucial role in adsorption. DFT calculations were used to reveal the effect of Cu and H2O in the desulfurization process. The adsorption energy of H2S on activated carbon was improved, and the energy barrier of the dissociation of H2S was decreased when Cu was introduced under the moist atmosphere. Density of states and the interaction region indicator (IRI) analyses indicated that the strong attractive force was formed between Cu and S. According to the results of DFT calculations, the presence of Cu and H2O could promote the adsorption of H2S. Combined with the experimental and calculation results, possible desulfurization mechanisms were proposed, which provides novel insights for the efficient removal of H2S by adsorptive desulfurization, especially under moist conditions.

Copper metabolism-related Genes in entorhinal cortex for Alzheimer's disease

The pathological features of Alzheimer's disease are the formation of amyloid plaques and entanglement of nerve fibers. Studies have shown that Cu may be involved in the formation of amyloid plaques. However, their role has been controversial. The aim of this study was to explore the role of Cu in AD. We applied the “R” software for our differential analysis. Differentially expressed genes were screened using the limma package. Copper metabolism-related genes and the intersection set of differential genes with GSE5281 were searched; functional annotation was performed. The protein–protein interaction network was constructed using several modules to analyse the most significant hub genes. The hub genes were then qualified, and a database was used to screen for small-molecule AD drugs. We identified 87 DEGs. gene ontology analysis focused on homeostatic processes, response to toxic substances, positive regulation of transport, and secretion. The enriched molecular functions are mainly related to copper ion binding, molecular function regulators, protein-containing complex binding, identical protein binding and signalling receptor binding. The KEGG database is mainly involved in central carbon metabolism in various cancers, Parkinson's disease and melanoma. We identified five hub genes, FGF2, B2M, PTPRC, CD44 and SPP1, and identified the corresponding small molecule drugs. Our study identified key genes possibly related to energy metabolism in the pathological mechanism of AD and explored potential targets for AD treatment by establishing interaction networks.

Understanding the role of Cu element in nanocrystalline hot deformed Nd-Fe-B magnets

Alloying with Cu element has long been established as a means of improving the performance of sintered NdFeB magnets, but its effect on nanocrystalline hot-deformed magnets has not been thoroughly discussed yet. In this study, we conducted a systematic comparison of the microstructure and magnetic properties of nanocrystalline Nd14Fe80B6 and Nd14Fe79B6Cu magnets. The results showed that the introduction of Cu significantly enhances the coercivity of both melt-spun and hot-deformed Nd-Fe-B magnets, owing to the improved magnetically decoupling between neighboring Nd2Fe14B matrix grains by the enrichment of Cu at Nd-rich grain boundary (GB) layer. Despite the magnetic dilution resulting from the introduction of non-magnetic Cu, a significant improvement of remanence from 11.0 kGs to 12.2 kGs is observed in the hot-deformed Nd-Fe-B magnet with 1 at.% Cu addition. The enhancement is attributed to the improved orientation of the Cu-added magnet, as evidenced by the preferential grain alignment from microstructural characterization. The addition of trace Cu changes the properties of the Nd-rich GB phase, lowering its melting point and improving the hot-workability of the Nd-Fe-B magnet during the hot-deformation process. Overall, this study clarifies the positive role of Cu in nanocrystalline Nd-Fe-B magnets and highlights its importance for grain alignment during hot-deformation processing.

Synergistic effect and mechanism of zero-valent iron activated persulfate on Cu(II)–EDTA decomplexation enhanced with weak magnetic field

Herein, a weak magnetic field (WMF) was applied to improve the catalytic degradation of the copper-ethylene diamine tetraacetic acid complex (Cu(II)–EDTA) and recovery of Cu using zero-valent iron/peroxomonsulfate (ZVI/PS). The removal rates of Cu(II)–EDTA in the WMF/ZVI/PS system were 7.92 and 1.33 times those in the ZVI and ZVI/PS systems, respectively. The recovery rates of Cu in the WMF/ZVI/PS system were 4.78 and 1.25 times more than those in ZVI and ZVI/PS systems, respectively. Scavenger quenching experiments and electron spin resonance (ESR) results showed that more active radicals (SO4•− and •OH) were produced and both SO4•− and •OH played the important role in Cu(II)–EDTA degradation in the WMF/ZVI/PS system. The ZVI and PS dosages and initial solution pH considerably affected the removal efficiency of Cu(II)–EDTA. X-ray energy-dispersive spectroscopy (EDS) results showed that WMFs could accelerate the enrichment of paramagnetic Cu2+ on the ZVI surface. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results showed that Cu2+ ions were first adsorbed on the corroded ZVI and then reduced to Cu0 with time. A possible Cu(II)–EDTA decomposition and Cu reduction mechanism was also proposed. This study provides a promising and ecofriendly technique for treating industrial wastewater containing organic complexed metals.

Electrochemical Reduction of N2O with a Molecular Copper Catalyst.

Deoxygenation of nitrous oxide (N2O) has significant environmental implications, as it is not only a potent greenhouse gas but is also the main substance responsible for the depletion of ozone in the stratosphere. This has spurred significant interest in molecular complexes that mediate N2O deoxygenation. Natural N2O reduction occurs via a Cu cofactor, but there is a notable dearth of synthetic molecular Cu catalysts for this process. In this work, we report a selective molecular Cu catalyst for the electrochemical reduction of N2O to N2 using H2O as the proton source. Cyclic voltammograms show that increasing the H2O concentration facilitates the deoxygenation of N2O, and control experiments with a Zn(II) analogue verify an essential role for Cu. Theory and spectroscopy support metal-ligand cooperative catalysis between Cu(I) and a reduced tetraimidazolyl-substituted radical pyridine ligand (MeIm4P2Py = 2,6-(bis(bis-2-N-methylimidazolyl)phosphino)pyridine), which can be observed by Electron Paramagnetic Resonance (EPR) spectroscopy. Comparison with biological processes suggests a common theme of supporting electron transfer moieties in enabling Cu-mediated N2O reduction.

Recent Progress of Copper-Based Nanomaterials in Tumor-Targeted Photothermal Therapy/Photodynamic Therapy.

Nanotechnology, an emerging and promising therapeutic tool, may improve the effectiveness of phototherapy (PT) in antitumor therapy because of the development of nanomaterials (NMs) with light-absorbing properties. The tumor-targeted PTs, such as photothermal therapy (PTT) and photodynamic therapy (PDT), transform light energy into heat and produce reactive oxygen species (ROS) that accumulate at the tumor site. The increase in ROS levels induces oxidative stress (OS) during carcinogenesis and disease development. Because of the localized surface plasmon resonance (LSPR) feature of copper (Cu), a vital trace element in the human body, Cu-based NMs can exhibit good near-infrared (NIR) absorption and excellent photothermal properties. In the tumor microenvironment (TME), Cu2+ combines with H2O2 to produce O2 that is reduced to Cu1+ by glutathione (GSH), causing a Fenton-like reaction that reduces tumor hypoxia and simultaneously generates ROS to eliminate tumor cells in conjunction with PTT/PDT. Compared with other therapeutic modalities, PTT/PDT can precisely target tumor location to kill tumor cells. Moreover, multiple treatment modalities can be combined with PTT/PDT to treat a tumor using Cu-based NMs. Herein, we reviewed and briefly summarized the mechanisms of actions of tumor-targeted PTT/PDT and the role of Cu, generated from Cu-based NMs, in PTs. Furthermore, we described the Cu-based NMs used in PTT/PDT applications.

The Cu(II) affinity constant and reactivity of Hepcidin-25, the main iron regulator in human blood

Hepcidin is an iron regulatory hormone that does not bind iron directly. Instead, its mature 25-peptide form (H25) contains a binding site for other metals, the so-called ATCUN/NTS (amino-terminal Cu/Ni binding site). The Cu(II)-hepcidin complex was previously studied, but due to poor solubility and difficult handling of the peptide the definitive account on the binding equilibrium was not obtained reliably. In this study we performed a series of fluorescence competition experiments between H25 and its model peptides containing the same ATCUN/NTS site and determined the Cu(II) conditional binding constant of the CuH25 complex at pH 7.4, CK7.4 = 4 ± 2 × 1014 M−1. This complex was found to be very inert in exchange reactions and poorly reactive in the ascorbate consumption test. The consequences of these findings for the putative role of Cu(II) interactions with H25 are discussed.

Simultaneous removal of Rhodamine B and Cu(II) by Fe0(1 1 0)-decorated ZSM-5: Cu(II) role, reactivity and mechanism

Cu(II) and Rhodamine B (RhB) were the typical contaminants in dyeing wastewater. This study synthesized zero-valent iron with (110) crystal decorated ZSM-5 (Fe0(110) @ZSM-5) to simultaneously removal Cu(II) and RhB, and explored the role of Cu(II) and Fe0 in RhB removal. The structure of Fe0(110) @ZSM-5 was further characterized by XRD, SEM, TEM, XPS, and RhB removal was investigated by batch experiment. The maximum RhB removal of 99.1% was attained at Fe0(110) @ZSM-5/H2O2/Cu(II) system, and Cu(II) played an important role. For Cu(II) concentration < 5 mg/L, uptake Cu(II) accelerating the electron transfer between Fe0 and Fe2+, and between Fe3+ and Fe2+. For Cu(II) concentration > 5 mg/L, the electron transfer was inhibited since the passivation layer of copper (hydro)oxides at Fe0(110)@ZSM-5 surface. Furthermore, adsorption (39%) and advanced oxidation (60.1%) were all involved in RhB removal. The maximum Cu(II) adsorption capacity was 132.31 mg/g, greater than many previously reported adsorbents.

Relevance of photocatalytic redox transformations of selected pharmaceuticals in a copper- and iron-rich Mediterranean intermittent river

This work aimed at investigating specific attenuation pathways of pharmaceuticals in copper- and iron-rich Mediterranean intermittent and sunlit rivers by combining lab- and field-scale studies. Poorly photodegradable and biodegradable compounds such as fluconazole, oxazepam and venlafaxine attenuated in two river stretches with short hydraulic residence times (<3 h). This result was assumed to be related to their capacity to interact with photoreactive free Cu2+ and Fe3+ or their associated oxides. Lab-scale photodegradation experiments under simulated solar irradiation revealed the beneficial impact of a mixture Cu2+ and colloidal iron hydroxides at environmental concentrations and at neutral pH on the pharmaceuticals photodegradation kinetic rate constants. These latter were consistent with the in-stream attenuation rate constants of targeted contaminants which ranged from 0.104 to 0.154 h−1. Further identification of phototransformation products by LC-HRMS highlighted reductive transformation pathways including reductive dehalogenation and hydrogenation reactions. Several TPs were found to be stable under irradiation and were detected in field monitoring, accordingly. This was ascribed to the formation of a Cu/Fe composite material under solar irradiation with photocatalytic properties. The role of Cu was to trap the electron in the conduction band of the iron-based photocatalyst, which promoted separation efficiency of electron-hole pairs as well as enhanced photoreduction processes at the expense of oxidation ones. Even though, these mechanisms have been reported in water treatment field for organic micropollutants removal, their significance was demonstrated for the first time in natural settings.

Revealing the Roles of Cu/Ba on Ce-Based Passive NOx Adsorbers

At present, passive NOx adsorbers (PNAs) represent one of the most effective technologies for addressing NOx emissions from diesel engines during cold-start periods. Conventional PNAs, which primarily consist of noble metals (such as Pt, Pd, and Ag) loaded on metal oxides or zeolites, share the common drawback of high production costs. Consequently, developing low-cost PNAs with outstanding NOx storage performance remains a significant challenge. In this study, a series of CuxBa5Ce adsorbents were synthesized using the impregnation method, and a monolithic adsorbent was employed to evaluate NOx storage and release performance. Techniques such as XRD, UV-Vis DRs, H2-TPR, XPS, and in situ DRIFTs confirmed the crucial roles of Cu and Ba in NOx storage and release. Specifically, the incorporation of Cu into CeO2 enhanced NOx storage performance. Moreover, in the Cu3Ba5Ce adsorbent, the addition of Ba not only introduced new storage sites and altered the stability of NOx adsorption species but also helped prevent the aggregation of CuO, thereby prolonging the complete NOx storage duration and satisfying desorption temperature requirements. The Cu3Ba5Ce adsorbent exhibited the most favorable NOx storage performance, including a complete NOx storage time of 135 s and a NOx storage efficiency exceeding 50% at 80 °C over a 10 min period. While PNAs loaded with noble metals, such as Pd/CeO2 and Pt/CeO2, exhibited NOx storage efficiencies below 50% after adsorbing for 5 min at 80 °C. Therefore, this research offered a crucial strategy for developing non-noble-metal-loaded, Ce-based PNAs.

Effect of Cu+/2+ ions on the biological activity of their bis‐oxalyldihydrazone complexes: ctDNA interaction, antimicrobial and anticancer action

Two bimetallic homoleptic complexes (CuL1 and CuL2) were synthesized from the coordination of Cu+/2+ ions with diisatin oxalyldihydrazone ligand (H2Lx), respectively. Confirmation of their chemical structures was based on the investigation of alternative spectroscopic tools. To distinguish the role of Cu+/2+ ion and its various charges on their complexes' reactivity, the bioreactivity of H2Lx, CuL1, and CuL2 was established on the spectral results against the growth of some microbial series (fungi and bacteria) and against three human cancer/normal cells. Furthermore, their behavior towards calf thymus DNA (ctDNA) was evaluated through viscometric and spectrophotometric titration. Both CuL1 and CuL2 complexes exhibited an amazing inhibiting effect against the growth of the titled microbial series and the human cancer cells, corresponded to the inhibited zone (mm), MIC (μM), and IC50 magnitudes (μM) and compared with those of their uncoordinated H2Lx ligand. CuL1 demonstrated a featured interacted behavior against ctDNA over that of CuL2 depending on the obtained intrinsic binding constants and the derived Gibbs' free energy values. The assigned nature of interaction could be built on the covalent and/or noncovalent modes, which supported by the electronegativity and electrophilicity of the titled studied compounds towards ctDNA.

Regulation of Atp7a RNA contributes to differentiation-dependent Cu redistribution in skeletal muscle cells.

Cu (Cu) is essential for several biochemical pathways due to its role as a catalytic cofactor or allosteric regulator of enzymes. Its import and distribution are tightly controlled by transporters and metallochaperones and Cu homeostasis is maintained by balancing Cu uptake and export. Genetic diseases are caused by impaired Cu transporters CTR1, ATP7A, or ATP7B but little is known about the regulatory mechanisms by which these proteins meet the fluctuating demands of Cu in specific tissues. Cu is required for differentiation of skeletal myoblasts to myotubes. Here, we demonstrate that ATP7A is needed for myotube formation and that its increased abundance during differentiation is mediated by stabilization of Atp7a mRNA via the 3'untranslated region. Increased ATP7A levels during differentiation resulted in increased Cu delivery to lysyl oxidase, a secreted cuproenzyme that needed for myotube formation. These studies identify a previously unknown role for Cu in regulating muscle differentiation and have broad implications for understanding Cu-dependent differentiation in other tissues.

Alzheimer's Disease and Age-Related Changes in the Cu Isotopic Composition of Blood Plasma and Brain Tissues of the APPNL-G-F Murine Model Revealed by Multi-Collector ICP-Mass Spectrometry.

Alzheimer's' disease (AD) is characterized by the formation of β-amyloid (Aβ) plaques and neurofibrillary tangles of tau protein in the brain. Aβ plaques are formed by the cleavage of the β-amyloid precursor protein (APP). In addition to protein aggregations, the metabolism of the essential mineral element Cu is also altered during the pathogenesis of AD. The concentration and the natural isotopic composition of Cu were investigated in blood plasma and multiple brain regions (brain stem, cerebellum, cortex, and hippocampus) of young (3-4 weeks) and aged (27-30 weeks) APPNL-G-F knock-in mice and wild-type controls to assess potential alterations associated with ageing and AD. Tandem inductively coupled plasma-mass spectrometry (ICP-MS/MS) was used for elemental analysis and multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS) for high-precision isotopic analysis. The blood plasma Cu concentration was significantly altered in response to both age- and AD-related effects, whereas the blood plasma Cu isotope ratio was only affected by the development of AD. Changes in the Cu isotopic signature of the cerebellum were significantly correlated with the changes observed in blood plasma. The brain stem showed a significant increase in Cu concentration for both young and aged AD transgenic mice compared with healthy controls, whereas the Cu isotopic signature became lighter as a result of age-related changes. In this work, ICP-MS/MS and MC-ICP-MS provided relevant and complementary information on the potential role of Cu in ageing and AD.

Boosting the photocatalytic CO2 reduction reaction over BiOCl nanosheet via Cu modification

The development of photocatalytic reduction of CO2 is hindered by slow surface reaction kinetics due to the high activation barrier of CO2 and the lack of activation centers in the photocatalyst. To overcome these limitations, this study focuses on enhancing the photocatalytic performance through incorporating Cu atoms into BiOCl. By introducing a minute amount of Cu (0.18 wt%) into BiOCl nanosheets, significant improvements were achieved, with a CO yield of 38.3 µmol g−1 from CO2 reduction, surpassing that of pristine BiOCl by 50%. To explore the surface dynamics of CO2 adsorption, activation and reactions, in situ DRIFTS was employed. Theoretical calculations were further performed to elucidate the role of Cu in the photocatalytic process. The results demonstrate that the incorporation of Cu into BiOCl induces surface charge redistribution, which facilitates efficient trapping of photogenerated electrons and accelerates the separation of photogenerated charge carriers. Furthermore, Cu modification on BiOCl effectively lowers the activation energy barrier by stabilizing the COOH* intermediate, thereby turning the rate-limiting step from COOH* formation to CO* desorption and boosting the CO2 reduction process. This work unveils the atomic-level role of modified Cu in enhancing the CO2 reduction reaction and presents a novel concept for achieving highly efficient photocatalysts.

Trace metals from microbial growth media form in situ electro-catalysts

Most microbial electrosynthesis systems depend heavily on the availability of hydrogen as electron carrier. To improve hydrogen availability in microbial processes, in situ hydrogen production is required with a catalyst that is compatible under microbial conditions (near-neutral pH, mesophilic temperature, aquous electrolyte). Here, we demonstrate the use of trace metal compounds from microbial medium as hydrogen evolution reaction (HER) electro-catalyst under microbial compatible conditions. Concentrated mixtures (10 vol%) of the metal compounds present in the microbial medium (trace metal mix medium; containing Co, Cu, Fe, Mn, Mo, Ni and Zn salts and ethylenediaminetetraacetic acid (EDTA)) were added to electrochemical reactors (controlled at -1.06 V vs Ag/AgCl and flushed with CO2/N2). After addition of the concentrated trace metal mix, the cathodic current increased up to 15 times with high electron recovery into hydrogen (70–100%). The formed HER catalyst performance was also measured in microbial growth medium (with ammonium and 0.1 vol% trace metal mix), showing similar performance rates compared to the concentrated trace metal mix medium. Further identification of the active compounds within the mix emphasized the role of Cu and Mo, a mix with Cu and Mo showed the same catalyst performance as the trace metal mix with all previously mentioned compounds. Moreover, the performance of the trace metal mix without EDTA showed the highest increased current (7 times higher up to -240 A/m2 or -80 kA/m3), decreased hydrogen overpotential (55 mV at -10 A/m2) and increased exchange current density (1.36 mA/m2). Integration of the discovered HER catalyst in biological systems will allow in situ hydrogen production in bio-electrochemical and fermentation systems.

Synergistic Roles of Hexagonal Boron Nitride-Supported Cu0 and Cu+ Species in Dehydrogenation of Ethanol to Acetaldehyde: A Computational Mechanistic Study

Copper-based catalysts have been widely used in the dehydrogenation of ethanol to acetaldehyde due to their high activity. However, the inhibition of sintering and the identification of active sites remain challenging. In this work, by means of periodic density functional theory calculations, the catalytic mechanism is reported at the molecular level. The strong metal–support interaction between Cu 3d orbitals and O 2p orbitals and the electron transfer determine the high stability of copper clusters supported on h-BN. The enhancement of the interfacial interaction (binding energies of −11.0 and −12.5 eV on Cu+/BN and Cu0/BN, respectively) resists the sintering of copper clusters and benefits the retention of their active states. The free energy barriers to the C–H bond cleavage are 1.20, 0.90, and 0.53 eV on Cu(111), Cu0/BN, and Cu+/BN, respectively, and the barriers to the dihydrogen formation are 0.42, 1.51, and 2.36 eV, respectively. The results show the promotion of the d-band in the supported Cu+ and Cu0 species and introduce a synergistic effect of the two species, with Cu+ participating in the dehydrogenation of ethanol to acetaldehyde and Cu0 in the formation of H2. This work explains the origin of the resistance of h-BN-supported copper clusters against their sintering and identifies the synergistic roles of the Cu+ and Cu0 species in ethanol dehydrogenation This knowledge is expected to contribute to the rational design of heterogeneous copper-based catalysts for efficient ethanol dehydrogenation.

Cu–Ce substituted cobalt nano ferrite - Structural, morphological, and magnetic behavior prepared by sol-gel auto-combustion

Sol-gel auto-combustion synthesized Co1-xCuxFe2-yCeyO4 (x = 0.0, 0.25, 0.5 and 0.75; y = 0.0, 0.03, 0.06, and 0.09), Cu–Ce substituted Co ferrite nanopowders. Investigations have been done on how Cu–Ce substitution affects the structural and magnetic characteristics. The Cu–Ce substitution variation effect on structural and magnetic properties is studied with X-ray diffraction (XRD), Field effect scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), and Vibrating sample magnetometer (VSM). The XRD was used to identify the crystal phase, and the role of Cu–Ce substituted for Co indicates how it formed. There is no change in the crystal structure, and no additional characteristic peak linked to Cu2+ and Ce3+ ions substitution was found in the XRD. The powder was sintered at 1100 °C. The crystallite sizes were found in between 33 and 62 nm. Increasing the Cu–Ce content decreases the lattice constant and is found between 8.4044 and 8.3309 Å. The FESEM images were used to analyze the nanostructural properties. The range of 110–128 nm is the value of average grain size. Two vibrational bands can be seen in FTIR spectra at about 600 cm−1 (v1) and 400 cm−1 (v2). They are attributed to the spinel lattices A and B sites, respectively. The tetrahedral site has a greater vibrational frequency of 566.09 cm−1, while the octahedral site has a lower vibrational frequency of 420.09 cm−1. FTIR spectra show the tetrahedral stretching peaks shifting towards lower frequencies with increasing Cu2+ and Ce3+ ions content. At ambient temperature, the magnetic properties of Cu–Ce substituted cobalt ferrites revealed a strong hysteresis loop. There was a decrease in magnetic saturation and an increase in coercivity.

A new antimicrobial PVC-based polymeric material incorporating bisacylthiourea complexes

A new antimicrobial material incorporating Cu(I) and Cd(II) complexes of bisacylthiourea derivatives in a PVC film was successfully synthesized and characterized by IR, UV, NMR, SEM, and thermal analyses. The results revealed that on coordination, the electronic structure change of the ligand affects practically all their spectral vibrational pattern; however, within the complex pattern, some vibrations indicated that the thiourea derivative behaves as a neutral ligand, which coordinates the metal ion through the sulfur atom of the thiocarbonyl group. The greater affinity of the S atom for Cu+ 1 played a role in Cu(II)→Cu(I) reduction, and the intramolecular hydrogen bonds of the type of (NH···Cl) further stabilized the obtained Cu(I) complex in dioxane. The antimicrobial activity shows that all investigated compounds exhibit excellent activity compared to standard antibiotics. The antibacterial power of the PVC/Cd composite is significantly superior against the most resistant species to both disinfectants and antibiotics compared to its PVC/Cu analogue; nevertheless, the latter exhibited activity equal to an average halo diameter of 29 ± 0.33 mm against pathogenic E. coli ATCC 25,922, indicating excellent G (-) activity. Interestingly, the PVC/Cd composite exhibited excellent activity against pathogenic C. albicans RCMB 005003 (1) ATCC 10,231, while its PVC/Cu analogue was inactive. These materials may be used to reduce infection in wounds either as a composite film or coated barrier dressings, and in addition, the results should open a new direction in antimicrobial surface engineering within the biomedical field. Further challenges are the development of reusable and broad-range antimicrobial polymers..