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Boron nitride nanosheets (BNNSs)-cellulose nanofibrils (CNF) nanocomposites have attracted significant interest as advanced materials for thermal management. However, their thermal conductivities are still insufficient due to the high interfacial thermal resistances (ITR) among the different components of the composites. In the present work, copper nanoparticles (CuNPs)-BNNS (Cu-BNNS) hybrid fillers were prepared by anchoring CuNPs on the BNNS surfaces using the liquid phase reduction method. Subsequently, the hybrid fillers were dispersed in a CNF matrix to produce the Cu-BNNS/CNF composite film, which exhibited high in-plane and out-of-plane thermal conductivities up to 37.5 ± 3.1 and 1.8 ± 0.026 W·m–1·K–1, respectively. The copper nanoparticles connecting the adjacent BNNSs contributed to reduced ITR and significant improvement of thermal conductivity. Specifically, CuNPs did not compromise the electrical insulation of the BNNS/CNF composites when enhancing their heat dissipation capability. The Foygel model developed for Cu-BNNS/CNF theoretically confirmed the role of copper nanoparticles. This study provides a feasible strategy for advancing the applications of BNNS and CNF in modern electronics for sustainable thermal management. [ABSTRACT FROM AUTHOR]

The extensive development of nanotechnologies has allowed nanoparticles to impact living systems through different pathways. The effect of single exposure to high concentrations of silver and copper nanoparticles (50–200 mg/L) on Vaccinium myrtillus L. under field conditions was investigated. Nanoparticle uptake in different segments of Vaccinium myrtillus L. was assessed by applying inductively coupled plasma–atomic emission spectroscopy and a particle-induced X-ray emission technique. Copper nanoparticles mainly accumulated in the roots and leaves, while silver nanoparticles showed a higher affinity for the roots and berries. The nanoparticles' effects on the pigments and antioxidant activity of the plant's leaves were also evaluated. The possible human health risk associated with the consumption of nanoparticle-contaminated berries was assessed. The results indicated that the consumption of berries contaminated with nanoparticles presented a low risk for human health. [ABSTRACT FROM AUTHOR]

This study investigates the development and application of electrospun wound dressings based on polylactic acid (PLA) nanofibers, chitosan, and copper nanoparticles (CuNPs) for the treatment of purulent skin wounds. The materials were evaluated for their structural, antibacterial, and wound healing properties using an animal model. PLA/Ch-CuNPs demonstrated the most significant antibacterial activity against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, surpassing the other tested materials. The integration of CuNPs into the nanofiber matrices not only enhanced the antimicrobial efficacy but also maintained the structural integrity and biocompatibility of the dressings. In vivo experiments using a rat model showed that PLA/Ch-CuNPs facilitated faster wound healing with reduced exudative and inflammatory responses compared to PLA alone or PLA-CuNPs. Histological and immunohistochemical assessments revealed that the combination of PLA, chitosan, and CuNPs mitigated the inflammatory processes and promoted tissue regeneration more effectively. However, this study identified potential toxicity related to copper ions, emphasizing the need for careful optimization of CuNP concentrations. These findings suggest that PLA/Ch-CuNPs could serve as a potent, cost-effective wound dressing with broad-spectrum antibacterial properties, addressing the challenge of antibiotic-resistant infections and enhancing wound healing outcomes. [ABSTRACT FROM AUTHOR]

The development of copper nanoparticle (CuNP)-based catalysts for the electrochemical reduction of carbon dioxide (ECO2-R) offers a promising approach to enhance its transformation into other industrially significant compounds. This study reports ECO2-R at -1.3 V vs RHE using CuNPs and catalytic inks composed of CuNPs and ionic liquids (ILs), observing significant differences in the selectivity of each catalyst. Specifically, CuNPs alone show a preference for producing ethylene and aqueous products, such as formic acid, ethanol, and formaldehyde. In contrast, the addition of ILs to the catalytic system redirects selectivity toward gaseous products, with methane being the main product. These findings highlight the potential to optimize catalyst composition to tailor the selectivity of CO2 conversion processes. ILs modify the catalytic environment and influence reaction pathways, enabling the selection of specific products. [ABSTRACT FROM AUTHOR]

The hybridization of single-walled carbon nanotubes (SWCNTs) and Cu nanoparticles offers a promising strategy for creating highly conductive and mechanically stable fillers for flexible printed electronics. In this study, we report the ultrafast synthesis of SWCNT/Cu hybrid nanostructures and the fabrication of flexible electrodes under ambient conditions through a laser-induced photo-thermal reaction. Thermal energy generated from the nonradiative relaxation of the π-plasmon resonance of SWCNTs was utilized to reduce the Cu-complex (known as a metal–organic decomposition ink) into Cu nanoparticles. We systematically investigated the effects of SWCNT concentration and output laser power on the structural and electrical properties of the SWCNT/Cu hybrid electrodes. The SWCNT/Cu electrodes achieved a minimum electrical resistivity of 46 μohm·cm, comparable to that of the metal-based printed electrodes. Mechanical bending tests demonstrated that the SWCNT/Cu electrodes were highly stable and durable, with no significant deformation observed even after 1000 bending cycles. Additionally, the electrodes showed rapid temperature increases and stable Joule heating performance, reaching temperatures of nearly 80 °C at an applied voltage of less than 3.5 V. [ABSTRACT FROM AUTHOR]

The synthesis of a nanocomposite material consisting of Cu nanoparticles encapsulated in halloysite nanotubes (Cu@Hal) was achieved by the reduction of Cu(NO3)2 ⋅ 3H2O with sodium ascorbate/sodium borohydride in an aqueous suspension of trisodium citrate and halloysite. The nanocomposite was found to be an effective heterogeneous catalyst for the multicomponent copper catalyzed azide‐alkyne cycloaddition reaction (CuAAC). A variety of terminal alkynes reacted with benzyl halides and sodium azide in the presence of Cu@Hal in water. In situ formation of the organic azides afforded the corresponding 1,4‐disubstituted 1,2,3‐triazoles regioselectivily, in excellent yields. The catalyst was easily recovered and recycled without loss of activity with low metal leaching. [ABSTRACT FROM AUTHOR]

Dandelion extract is a reducing agent, and CuSO4∙5H2O was used as a carrier to create copper nanoparticles (CuNPs). A novel polyvinyl alcohol–chitosan–dandelion–CuNP (PVA/CTS/DAN/CuNP) gel was acquired by cross-linking Polyvinyl alcohol (PVA) and chitosan (CTS) solution. Its structure was analyzed using Fourier transform infrared spectroscopy, Scanning electron microscopy, and X-ray diffraction. The PVA/CTS/DAN/CuNP gels manifested good stability, recycling ability, swelling properties, and biocompatibility. Using the agar diffusion method, the diameters of the inhibition zone of the composite gel against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa could be over 21 mm. In conclusion, the PVA/CTS/DAN/CuNP composite gel had good antibacterial performance, which has a high potential for application in microbial contamination treatment and environmental protection. [ABSTRACT FROM AUTHOR]

[Display omitted] In this study, we introduce a hydrogel-polymer microsphere (HPM) composite material constituted of PVA, glycerin, and polymer microspheres obtained from Pickering emulsions that are capable of adsorbing Cu2+ ions. The obtained HPM composite is soft, flexible, can be fully saturated with Cu2+ ions, and exhibits a reversible color transition from blue to black upon electrode contact or interaction with a reducing agent, due to in situ generation of copper nanoparticles (Cu-NPs). Because of the color contrast between the locally generated Cu-NPs and the background, the HPM can be used as substrate for stamping different shapes or writing text. Further, the surface can be erased by an acidic solution, which makes it interesting as flexible write-erase displays. A second feature of the HPM is that it can function as a fluorescence detector of cyanide ions. An HPM whose surface has been stamped with an electrode, upon contacting an aqueous solution containing cyanide ions, begins fluorescing a yellow-green light around the patterned area. The displayed luminescence is irreversible and is preserved even after HPM's drying or lyophilization. This work lays a foundational framework for future exploration of the HPM composites in various technological applications, for sensing, circuit printing, and flexible displays. [ABSTRACT FROM AUTHOR]

A considerable amount of fruit waste is being produced every day worldwide. The green synthesis of metal nanoparticles from fruit peel waste can be an innovative, cost-effective, and eco-friendly alternative to traditional methods. Copper nanoparticles (CuNPs) were synthesized by a green method using the pineapple peels extract (PLX) and copper sulfate pentahydrate. The formation of CuNPs was visually identified and detected by UV–Visible spectroscopy. The CuNPs were characterized by Fourier-transform infrared (FTIR) spectroscopy, particle size analyzer, scanning electron microscopy (SEM), and X-ray diffraction (XRD). The antioxidant and reducing power of CuNPs were conducted by %DPPH scavenging and electron transfer-based ferric reducing antioxidant power (FRAP) assay, respectively. The antibacterial properties of CuNPs were determined in gram-positive, and gram-negative bacteria. The results showed that the CuNPs were spherical in shape with mean particle size 290.5 nm. The zeta potential of the nanoparticles was found to be − 12.3 mV indicating the instability in the colloidal state. The FTIR study confirmed the peaks of phytochemicals present in the PLX and the nanoparticles supporting the use of pineapple peels as stabilizing, reducing and capping agents. Both the DPPH and reducing power assay depicted that the synthesized CuNPs had significant antioxidant activity. However, the synthesized CuNPs had strong inhibitory capacity against both gram-positive and gram-negative test organisms. Thus, the CuNPS could be used for its viable antibacterial potential to preserve fruits, flowers, and vegetables from bacterial contamination. [ABSTRACT FROM AUTHOR]

This paper investigated the development and characterization of conductive textured and non-textured polyester fabrics with various cross-sections. To impart conductivity on fabric structures, the electroless copper plating method was chosen. Electrical conductivity, thickness, electron scanning microscopy (SEM), microscopic morphology, and energy dispersive X-ray spectroscopy were used to characterize the deposition of copper nanoparticles on textured and non-textured polyester fabrics (EDX). SEM images revealed a thin film of uniform copper nanoparticle coating on textured and non-textured polyester fabrics. Electrical conductivity, wear resistance, thickness, and durability of conductive textured polyester fabrics were compared to non-textured conductive polyester fabrics. Electrical conductivity measurements show that both textured and non-textured polyester fabrics have good electrical conductivity values of 27Ω/cm, 85Ω/cm, 52Ω/cm, 9Ω/cm, 98Ω/cm, 133Ω/cm. When conductive polyester fabrics were tested for durability against washing and rubbing fastness, the textured polyester fabrics retained copper nanoparticles well by maintaining their electrical conductivity level after 250 abrasion and washing cycles, with best electrical conductivity values of 177Ω/cm and 29Ω/cm, respectively. [ABSTRACT FROM AUTHOR]

The resistance of pathogenic microorganisms to antibiotics is one of the main problems of world health. Of particular concern are multidrug-resistant (MDR) bacteria. Infections caused by these microorganisms affect the appearance of acute or chronic diseases. In this regard, modern technologies, such as nanomaterials (NMs), especially promising nanoparticles (NPs), can possess antimicrobial properties or improve the effectiveness and delivery of known antibiotics. Their diversity and characteristics, combined with surface functionalization, enable multivalent interactions with microbial biomolecules. This article presents an overview of the most current research on replacing antibiotics with NPs, including the prospects and risks involved. [ABSTRACT FROM AUTHOR]

Abstract The growth of material science and technology places high importance on creating better processes for synthesizing copper nanoparticles. Thus, an easy, ecological, and benign process for producing copper nanoparticles (CuNPs) has been developed using Priestia sp. bacteria utilizing a variety of low-cost agro-industrial wastes and byproducts. The biosynthesis of CuNPs was conducted using glucose medium and copper ions salt solution, then it was replaced by utilizing low-cost agro-industrial wastes. UV–visible spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), High-resolution transmission electron microscope (HR-TEM), Attenuated Total Reflectance and Fourier transform infrared (ATR-FTIR), and zeta potential were used to characterize the biosynthesized CuNPs. The cytotoxicity of CuNPs using Vero -CCL-81 cell lines, and antibacterial and antitumor properties using human colon epithelial colorectal adenocarcinoma Caco-2-HTB-37 cell lines were assessed. The UV–visible and DLS studies revealed CuNPs formation, with a maximum concentration of 6.19 ppm after 48 h, as indicated by a 0.58 Surface plasmon resonance (SPR) within 450 nm and 57.73 nm particle size. The 16S rRNA gene analysis revealed that Priestia sp. isolate is closely related to Priestia megaterium and has been deposited in the NCBI GenBank with accession number AMD 2024. The biosynthesis with various agro-industrial wastes indicated blackstrap sugar cane molasses being the most effective for reducing CuNPs size to 3.12 nm owing to various reducing and stabilizing active compounds. The CuNPs were free of contaminants, with a sphere-shaped structure and a cytotoxicity assessment with an IC50 of 367.27 μg/mL. The antibacterial activity exhibited by the most susceptible bacteria were Bacillus cereus ATCC 11788 and Staphylococcus aureus ATCC 6538 with inhibition zones of 26.0 mm and 28.0 mm, respectively. The antitumor effect showed an IC50 dose of 175.36 μg/mL. Based on the findings, the current work sought to lower product costs and provide a practical solution to the environmental contamination issues brought on by the buildup of agricultural wastes. In addition, the obtained CuNPs could be applied in many fields such as pharmaceuticals, water purification, and agricultural applications as future aspects.

The development and creation of innovative therapeutic supplements and medications with extraordinary efficacy for addressing severe diabetes are of utmost importance to both developing and developed nations. A bio-inspired method has been documented for producing copper nanoparticles (CuNPs) using Pistacia atlantica leaf extract as a natural stabilizing agent. This approach is applicable, easy, and environmentally friendly, as it avoids using any toxic or harmful reagents. The CuNPs that were synthesized through biological processes underwent characterization using sophisticated physicochemical methods such as energy-dispersive X-ray spectroscopy, transmission electron microscopy, field emission-scanning electron microscopy, and Fourier-transformed infrared spectroscopy. It is confirmed that CuNPs exhibit a spherical structure, with an average size ranging from approximately 30 to 70 nm. Diabetes was induced in vivo through a fructose-enriched diet combined with streptozotocin. Half the subjects were administered CuNPs (100 µg/kg) via oral gavage. In contrast to the animals that were given regular food, the diabetic animals revealed an increase in serum fasting glucose level and a decrease in glucose tolerance. The administration of CuNPs had a significant impact on reducing glucose intolerance and fasting hyperglycemia. Additionally, it helped alleviate the negative effects of diabetes on cardiac output and work. Furthermore, utilizing CuNPs effectively hindered the rise in cardiac signal transducer and activator of transcription 3-phosphorylation caused by diabetes. The findings from this investigation provide evidence of the therapeutic benefits of CuNPs in mitigating diabetes-induced cardiac dysfunction in rats.

Nanotechnology has been progressively developed recently and used extensively in all disciplines. These nanoscale particles overpower the use of conventional technological metal particles. Applications of Cu nanoparticles in agriculture enhance production and soil fertility, albeit their usage in excess amounts causes toxicity for soil fauna. So, we studied and collated the toxicity research trends of copper nanoparticles in the worm’s species (earthworms and enchytraeids) and their activities to assess the consequences of copper nanoparticles in varied sizes and oxidation states. Various Cu NPs have a high capacity for adsorbing biomolecules and interacting with biological receptors. Cu NPs can interact with the host organism’s inherent immunity and impair the host’s immune system when confronted with different dose concentrations. These artificially induced nanoparticles interpret the biological cell system and manipulate cell receptors in situ. Nations all across the world are currently attempting to establish a global policy on the regulation of nanomaterials as per their ecological safety. In some cases, they have been reported to be more hazardous than the comparable ions and micromaterials in some cases. As a result, nanoparticle safety research has far-reaching ramifications for national economies. These studies will be extremely significant in regulating the environmental outcome of nanoparticles.

Green-synthesized silver and copper nanoparticles (NPs), along with their composites, exhibit various biological activities. Ocimum sanctum (Holy basil), traditionally used as medicine in South Asia, treats respiratory disorders, digestive issues, skin diseases and inflammatory conditions. Modern scientific studies support these bioactivities; however, no studies have investigated their bioactivity in combination with NPs. In this study, silver and copper NPs were synthesized using AgNO3 and CuSO4·5H2O solutions, respectively, with Ocimum sanctum leaf extract, and their antibacterial, antioxidant and anticancer properties were examined. Spectroscopic analyses, including Fourier transform infra-red (FTIR), transmission electron microscopy (TEM) and X-ray diffraction (XRD), elucidated the physicochemical characteristics of the green-synthesized nanoparticles (Os-AgNPs and Os-CuNPs), revealing sizes of 11.7 and 13.1 nm, respectively. The Os-AgNPs:Os-CuNPs nano-composite with a 1:2 ratio exhibited a zone of inhibition ranging from 8 to 12 mm against tested bacterial pathogens. Additionally, the NPs and their composites demonstrated potent antioxidant activity, with notable 2-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity observed in composites with ratios of 2:1 and 1:2. Furthermore, they displayed potential anticancer activity against human leukaemia (Jurkat) cancer cells. Although no distinct difference in anticancer property was observed among the NPs and their composites, our study highlights their well-defined nanostructure and significant biological activity, suggesting their potential as therapeutic agents in the pharmaceutical industry.

Copper nanoparticles (CuNPs) were successfully prepared in Cu+–Na+ ion‐exchanged commercially available silicate glasses followed by being annealed in Ar/H2 atmosphere; in an approach that can be quite economic capable of modifying the physicochemical properties of glass. This approach resulted in the growth of spherical and crystalline CuNPs, with an average size of 67.5 nm, which is greater than the CuNPs average size obtained with annealing at air atmosphere (15.8 nm). On the treated glasses, phase transitions indicative of a shape memory effect and dendritic structures were also detected, indicating their vital roles, as crystal growth mechanisms in the resultant CuNPs. The surface plasmon peaks of CuNPs have been clearly observed in absorption spectra of doped annealed glasses at 350, 450, and 550°C in Ar/H2. Photoluminescence studies have proved the presence of both Cu+ and Cu2O. The detailed methodology and the structural and morphological characterizations of the annealed copper ion‐exchanged samples were carried out using optical microscopy (OM), X‐ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy and high‐resolution TEM (TEM and HRTEM), and their reasoning are thoroughly described and discussed. [ABSTRACT FROM AUTHOR]

The frequency of lung infection induced by multi-drug resistant strains of Pseudomonas aeruginosa has significantly risen, primarily due to the inadequate effectiveness of powerful chemotherapeutic methods. This study demonstrates that the Ocimum basilicum aqueous extract and copper nanoparticles (CuNPs) exhibited significant antioxidant and anti-infectious properties under in vivo conditions. To analyze the characteristics of the CuNPs synthesized from the reaction between copper nitrate solution and the aqueous O. basilicum extract, various techniques such as energy dispersive X-ray analysis, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction analysis, and transmission electron microscopy were employed. The in vivo study encompasses the assessment of P. aeruginosa lethal dose in mice and the disease manifestation analysis, which comprises reduction in body weight, hypothermia, bacteremia, and other parameters, over a 48 h infection period. The infected mice exhibited a notable decrease in body temperature, measuring at 25°C after 48 h, compared to the initial temperature of 39°C. Additionally, a 30% reduction in weight was seen at the conclusion of the study. To assess the effectiveness of CuNPs on lung infection caused by the calculated lethal dose and bacteremia, histopathology analysis was employed. The bacterial load in the CuNPs group was determined to be 0.5 Log10CFU/mL on Day 8, indicating a notable decrease from the initial measurement of 1.5 Log10CFU/mL on Day 1. The histopathological findings revealed a widespread and sporadic buildup of alveolar space inflammatory cells, with infiltrates observed throughout all lung sections in infected mice. Enhanced lung histology was observed in the group of animal treated with reduced exudates noted at 200 µg/kg. CuNPs demonstrated inhibitory effects on the growth of P. aeruginosa at 8 µg/mL, while at 16 µg/mL, they effectively eradicated P. aeruginosa. The research unequivocally demonstrates the efficacy of CuNPs extract in combating lung infections induced by P. aeruginosa at 200 µg/kg. The recent survey aims to further explore the biomedical characteristics of these CuNPs in order to develop a powerful treatment against this dangerous pathogen.

Abstract Conductive polymer nanocomposites for electromagnetic interference (EMI) shielding are important materials that can be combat the increasingly dangerous radiation pollution arising from electronic equipment and our surrounding environment. In this work, we have synthesized polyaniline-copper nanoparticles (PANI-Cu NPs) by the copper salt based oxidative polymerization method at room temperature and then added with different concentration (0, 1, 3 and 5 wt%) in polystyrene polymer forming PS/ PANI-Cu nanocomposites films by means of the traditional solution casting technique. The formed PANI-Cu NPs were investigated by UV/Vis spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM) and SEM/EDX elemental mapping techniques. On the other hand, the prepared PS/PANI-Cu nanocomposites films were evaluated by UV and SEM, the mechanical properties of the nanocomposites films were evaluated and showed an improvement by added PANI-Cu NPs up to 3 wt% and 50 kGy gamma exposure dose. The PS/PANI-Cu nanocomposites films were examined as electromagnetic interference shielding material. Electromagnetic shielding effectiveness of the produced nanocomposites were tested in the X-band of the radio frequency range namely from 8 to 12 GHz using the vector network analyzer (VNA) and a proper wave guide. All samples were studied before and after 50 kGy gamma-ray irradiation under the same condition of pressure and temperature. The results showed that the nanocomposites have improved shielding properties.

Biosynthesis of metal nanoparticles is a cost-effective and environmentally friendly technology. In the present study, copper nanoparticles (CuNPs) were synthesized using white tea leaf extracts. They were then characterized for their chemical structure and evaluated ability for the methylene blue (MB) degradation in the adsorption system with H2O2. XRD and FTIR analyses revealed that the CuNPs were present as an amorphous phase, with the O-H polyphenol compound bound to the Cu ion. The XPS deconvolution indicated the presence of Cu2+ and Cu+ in the CuNPs. TEM images revealed that the average particle size was less than 10 nm. The CuNPs synthesized using different precursors exhibited effective ability for the MB degradation in the adsorption system. Based on the adsorption theory, the pseudo-second-order model fitted well with the experimental data, and the thermodynamic calculation suggested that the reaction was endothermic, and spontaneous. The CuNPs synthesized using the CuSO4 precursor exhibited higher antibacterial activity compared to those synthesized using Cu(NO3)2. In conclusion, white tea leaf extract is an inexpensive and easily available precursor for the biosynthesis of copper nanoparticles. Further analysis based on an assumed degradation work will be considered in future work.

Abstract The growth of material science and technology places a high importance on the creation of better processes for the synthesis of copper nanoparticles. So that, an easy, ecological, and benign process for producing copper nanoparticles (CuNPs) has been developed using candy leaf (Stevia rebaudiana) leaves aqueous extract for the first time. UV-visible spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), high-resolution transmission electron microscope (HR-TEM), Fourier transmission infrared (FTIR), and zeta potential were applied to demonstrate strong characterization for the biosynthesized stevia-CuNPs. The UV-visible absorbance at 575 nm of surface plasmon resonance (SPR) was 1.2. The particle size mean diameter was recorded as 362.3 nm with − 10.8 mV zeta potential. The HR-TEM scanning revealed 51.46–53.17 nm and spherical-shaped stevia-CuNPs surrounded by coat-shell proteins. The cytotoxicity and cytocompatibility activity assay revealed that stevia-CuNPs was safe in lower concentrations and had a significant cell viability reduction in higher concentrations. The produced stevia-CuNPs were applied as antimicrobial agents against eight pathogenic bacteria and five fungi strains. The inhibitory action of the stevia-CuNPs was more pronounced in bacteria than in fungi, and they likewise demonstrated further inhibition zones in Staphylococcus aureus (50.0 mm) than in Aspergillus flavus (55.0 mm). With inhibition zone sizes of 50.0 mm and 47.0 mm and 50 µg/ml minimum inhibitory concentration, S. aureus and A. flavus were the most inhibited pathogens. The minimum lethal effect (MLC) estimate for S. aureus was 50 µg/ml, whereas 75 µg/ml for A. flavus. The stevia-CuNPs mode of action was characterized as bactericidal/fungicidal as the ratio of MIC to MLC was estimated to be equal to or less than 2. After all, stevia-CuNPs could be used as an alternative to commercial antibiotics to solve the problem of multidrug-resistant (MDR) microorganisms.

Conductive polymer nanocomposites for electromagnetic interference (EMI) shielding are important materials that can be combat the increasingly dangerous radiation pollution arising from electronic equipment and our surrounding environment. In this work, we have synthesized polyaniline-copper nanoparticles (PANI-Cu NPs) by the copper salt based oxidative polymerization method at room temperature and then added with different concentration (0, 1, 3 and 5 wt%) in polystyrene polymer forming PS/ PANI-Cu nanocomposites films by means of the traditional solution casting technique. The formed PANI-Cu NPs were investigated by UV/Vis spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM) and SEM/EDX elemental mapping techniques. On the other hand, the prepared PS/PANI-Cu nanocomposites films were evaluated by UV and SEM, the mechanical properties of the nanocomposites films were evaluated and showed an improvement by added PANI-Cu NPs up to 3 wt% and 50 kGy gamma exposure dose. The PS/PANI-Cu nanocomposites films were examined as electromagnetic interference shielding material. Electromagnetic shielding effectiveness of the produced nanocomposites were tested in the X-band of the radio frequency range namely from 8 to 12 GHz using the vector network analyzer (VNA) and a proper wave guide. All samples were studied before and after 50 kGy gamma-ray irradiation under the same condition of pressure and temperature. The results showed that the nanocomposites have improved shielding properties. [ABSTRACT FROM AUTHOR]

The capture and utilization of carbon dioxide (CO2) as a C1 source for valuable compounds and fuel production are essential in mitigating the escalating atmospheric carbon dioxide. In this context, the present study demonstrates rational integration of an efficient, highly recyclable, and noble-metal-free catalyst for effectively utilizing CO2 to prepare valuable commodity compounds and antibiotics. To achieve this, we anchored catalytically active, alkynophilic Cu(0) nanoparticles (Cu-NPs) with an average size of 10 nm in a high surface area (1079 m2/g), amine-functionalized MOF via the postsynthetic method. The resulting Cu NP-embedded MOF (Cu-NPs/MOF) demonstrates high CO2 uptake and superior catalytic performance for generating 2-oxazolidinones and α-alkylidene cyclic carbonates by CO2 coupling with propargylic amines and alcohols, respectively. More importantly, a facile one-pot preparation of 2-oxazolidinones, antibacterial agents, through a four-component reaction between readily accessible phenylacetylene, acetone, amine, and CO2 has also been accomplished using Cu-NPs/MOF as a catalyst. The high performance of the Cu-NPs/MOF is attributed to the synergistic participation of CO2-philic NH2 groups and catalytic Cu-NPs, rendering selective capture and utilization of carbon dioxide. Further, the Cu-NPs/MOF showed excellent recyclability over six cycles, retaining its catalytic performance and chemical stability. This work highlights the importance of CO2 utilization for one-pot synthesis of valuable 2-oxazolidinones by a four-component reaction involving C–H bond functionalization of phenyl acetylenes at mild conditions. [ABSTRACT FROM AUTHOR]

Copper nanoparticles were synthesized from Aloe vera leaf gel extract concentrate from 0.1 Molar Copper sulphate pentahydrate solution. The Aloe vera gel concentrate and copper sulphate solution during the process were subjected to spectrophotometric absorption studies. Prepared nanoparticles were observed for size, zeta potential and polydispersity index, scanning electron microscopy, and energy dispersive X-ray analysis. The results showed that the size of elemental copper synthesized with the help of Aloe vera leaf gel extract concentrate was 272nm. SEM analysis confirmed the morphology of synthesized nanoparticles (spherical shapes). EDX studies further confirmed the presence of 67.21% elemental copper in newly synthesized nanoparticles prepared from Aloe vera leaf gel concentrate. The process of green synthesis uses eco-friendly resources to increase biological safety. The Aloe vera leaf gel extract concentrate efficiently served as a reducing and a capping agent to reduce the size of copper particles to the nanoparticle range. The method is low in cost and saves energy. [ABSTRACT FROM AUTHOR]

One of the more important factors responsible for synaptic dysfunction of neurons is neurological ageing. It is a natural consequence of occurrence of biochemical pathways in cells, promoting oxidation processes, an increase in the amount of free oxygen radicals that damage DNA, disorders in calcium ion homeostasis, interactions between lipids of cell membranes, formation of neurofibrillary tangles and deposition of toxic protein deposits. Diet modifications can delay neurometabolic disorders that occur as a result of ageing, as well as limit the development of neurodegenerative diseases. The aim of this study on rats was to verify the hypothesis regarding the effect of dietary addition of copper nanoparticles (CuNPs; instead of standard CuCO3) in combination with various dietary fibers on changes in hippocampus and jejunum biochemical parameters related to metabolic disorders appearing with neurological ageing in rats. Male rats were fed a control diet with fiber α-cellulose and a standard or enhanced content of Cu provided as CuCO3 (6.5 or 13 mg/kg diet). The diets of other groups were deprived of CuCO3 and the animals were fed diets supplemented with two CuNPs aforementioned doses, and additionally combined with four different types of dietary fiber: α-cellulose (control fiber), pectin, inulin or psyllium (Plantago psyllium). The addition of dietary CuNPs increased the level of acetylcholinesterase (AChE) and decreased the levels of Tau protein, glycosylated AChE (GAChE) and Ca/calmodulin dependent protein kinase II alpha (CAMK2α) in the examined organs. To sum up, both applied doses of CuNPs, 6.5 mg and 13 mg per kg of a diet, can beneficially modulate some important parameters describing metabolic and neurodevelopmental status in the hippocampal and small intestinal tissue of rats. With regard to the fiber type added to rats' diet, the Plantago psyllium fiber strengthened the mentioned effects of copper nanoparticles. The observed effects should be confirmed in a model study of neurodegeneration. [ABSTRACT FROM AUTHOR]

This study focuses on the effect of copper nanoparticles and graphene oxide nanosheets on the tensile properties and impact strength of epoxy-based hybrid nanocomposites. A mechanical mixer and an ultrasonicator were used to mix the reinforcements with the epoxy resin. Field Emission Scanning Electron Microscope (FE-SEM) was used to examine the fracture surface morphology, and tensile and impact tests were conducted to assess the mechanical properties of the nanocomposites. These properties were optimized by a genetic algorithm. The results showed that adding 0.75 wt% copper nanoparticles and 1 wt.% graphene oxide to the epoxy increased its tensile strength by 45.7 and 37.14%, respectively, compared with those of pure epoxy, and adding 0.5 wt% graphene oxide and 0.75 wt% copper nanoparticle led to a 61.76 and 32.35% increase in its fracture strength. The tensile test results indicated that the tensile strength of specimens reinforced with 0.125 wt% graphene oxide and 0.125 wt% copper nanoparticles increased by 47.51% compared with those of pure epoxy and adding 0.375 wt% graphene oxide and 0.375 wt% copper nanoparticles increased the fracture energy by 91.18%. [ABSTRACT FROM AUTHOR]

Printed circuit boards, which make up part of waste from electrical and electronic equipment, contain elements that can be economically reused, such as copper, silver, gold, and nickel, as well as metals that are harmful to the environment and health, such as lead, mercury, and cadmium. Thus, through recycling this scrap, materials that would otherwise be discarded can be reinserted as secondary raw materials to produce new consumer goods through urban mining. In this context, the synthesis of nanoparticles shows promise as it allows the reinsertion of these materials in the manufacture of new products. Therefore, this study used obsolete computer motherboards as a secondary material to obtain copper to produce nanoparticles of this metal. From a solution based on the leach liquor of this scrap, a purification route using solvent extraction was defined and applied to the real leach liquor. Applying the hydroxyoxime extractant at a dilution of 20% (v/v) in kerosene, A/O of 1/1, 298 K, and 0.25 h of contact during extraction, and stripping in H2SO4 (2 M), 298 K, 0.25 h, W/O ratio of 3/1, and two theoretical countercurrent stages, a solution containing more than 95% of the copper in the leach liquor could be obtained with less than 1% of contaminants. From this purified liquor, nanoparticles containing copper and metallic copper oxides and hydroxides were produced, with an average size of 84 nm, at pH 11, 3 h of hot stirring, volume of 0.015 L of ascorbic acid (0.50 M) and 0.015 L of precursor solution (0.03 M Cu), and temperature (343 K). [ABSTRACT FROM AUTHOR]

The potential of a voltametric E-tongue coupled with a custom data pre-processing stage to improve the performance of machine learning techniques for rapid discrimination of tomato purées between cultivars of different economic value has been investigated. To this aim, a sensor array with screen-printed carbon electrodes modified with gold nanoparticles (GNP), copper nanoparticles (CNP) and bulk gold subsequently modified with poly(3,4-ethylenedioxythiophene) (PEDOT), was developed to acquire data to be transformed by a custom pre-processing pipeline and then processed by a set of commonly used classifiers. The GNP and CNP-modified electrodes, selected based on their sensitivity to soluble monosaccharides, demonstrated good ability in discriminating samples of different cultivars. Among the different data analysis methods tested, Linear Discriminant Analysis (LDA) proved to be particularly suitable, obtaining an average F1 score of 99.26%. The pre-processing stage was beneficial in reducing the number of input features, decreasing the computational cost, i.e., the number of computing operations to be performed, of the entire method and aiding future cost-efficient hardware implementation. These findings proved that coupling the multi-sensing platform featuring properly modified sensors with the custom pre-processing method developed and LDA provided an optimal tradeoff between analytical problem solving and reliable chemical information, as well as accuracy and computational complexity. These results can be preliminary to the design of hardware solutions that could be embedded into low-cost portable devices. [ABSTRACT FROM AUTHOR]

Copper nanoparticles (CuNPs) are extensively used in electronics, cosmetics, fungicides, and various other fields due to their distinctive qualities. However, this widespread usage can contribute to environmental contamination and heightened health risks for living organisms. Despite their prevalent use, the ecological impacts and biosafety of CuNPs remain inadequately understood. The present study aims to delve into the potential toxic effects of CuNPs on zebrafish (Danio rerio) embryos, focusing on multiple indexes such as embryonic development, neurotoxicity, oxidative stress, and inflammatory response. The results revealed a notable increase in the death rate and deformity rate, alongside varying degrees of decrease in hatching rate and heart rate following CuNPs exposure. Particularly, the frequency of spontaneous tail coiling significantly declined under exposure to CuNPs at concentrations of 500 µg/L. Furthermore, CuNPs exposure induced alterations in the transcriptional expression of GABA signaling pathway-related genes (gabra1, gad, abat, and gat1), indicating potential impacts on GABA synthesis, release, catabolism, recovery, and receptor binding. Additionally, CuNPs triggered oxidative stress, evidenced by disruption in superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities, along with elevated malondialdehyde (MDA) levels. This oxidative stress subsequently led to a proinflammatory cascade, as demonstrated by the increased transcriptional expression of inflammatory markers (il-1β, tnf-α, il-6, and il-8). Comparative analysis with copper ion (provided as CuCl2) exposure highlighted more significant changes in most indexes with CuCl2, indicating greater toxicity compared to CuNPs at equivalent concentrations. In conclusion, these findings provide valuable insights into the toxic effects of CuNPs on zebrafish embryo development and neurotransmitter conduction. Furthermore, they present technical methodologies for assessing environmental and health risks associated with CuNPs, contributing to a better understanding of their biosafety and ecological impact. [ABSTRACT FROM AUTHOR]

Copper nanoparticles (Cu-NPs) are becoming increasingly prevalent in the environment due to their wide range of applications, posing potential threats to living organisms. Negative effects of Cu-NP exposure have been confirmed in many fish species, and they include disorders in the expression of oxidative stress genes and the activity of enzymes they encode. Common carp, known for its sensitivity to nanopollutants in water, serves as a valuable model organism for nanoparticle toxicity assessment. This study investigated the effects of specific Cu-NPs – copper nanopowder (Cu-NPs), colloidal copper nanoparticles (Cu), and copper oxide nanoparticles (CuO-NPs) – on gene expression and enzyme activity (GPX, CYP1A, HSP70, SOD, CAT) in C. carpio hatchlings, utilizing molecular biology tools and biochemical analyses. Results showed that Cu increased the expression of the hsp70 gene, Cu-NPs elevated the expression of the cyp1a and hsp70 genes, and CuO increased cyp1a expression. Conversely, sod and cat exhibited reduced expression across all samples (Cu, Cu-NPs, CuO). All Cu forms induced significant ROS accumulation and notable alterations in oxidative stress biomarkers (SOD, CAT, GPX). [ABSTRACT FROM AUTHOR]

The unearthing of various forms of broad and narrow-spectrum antibiotics have helped mankind combat various forms of microbic infections ranging from protozoal to bacterial. The applicability of antibiotics has been decisive in a wide range of frontline therapeutic dealings. An extensive use of antibiotics and certain genetic modifications in microbes has paved the way for a new issue to be answered by the scientific community, an antibiotic resistance. An unparallel infections triggered by multidrug-resistant organisms (MDRO) account to be a major cause of mortality and morbidity, today this situation demands the development of alternative strategies of cure and medicine by the scientific community. Study shows the amplification of the effect of antibiotics may be a possible route to address antibiotic resistivity. The assortment of various surface properties of nanoparticles (NPs) coupled with their ability to efficiently bind with bacterial surfaces leading to the rupture and lysis of cell deliberates potential strategies to manage infections caused by MDROs.The present study scrutinizes the amplification of the antibacterial activity of ciprofloxacin (CIP) against the bacterial strains of Staphylococcus aureus, Escherichia coli, Pseudomonas and Streptococcus mutans on coupling with synthesized copper, silver and zinc oxide NPs (ZnO NPs) by disc diffusion technique. The current study describes the efficacious synthesis and characterization of ZnONP, copper Nps (CuNPs) and silver NPs (AgNPs) followed by the induced amplification of the antibacterial activity of CIP by coupling it with synthesized metal/metal oxide (M/MO NP). The synthesized M/MO NPs were characterized using XRD and FE-SEM studies and TEM. The results indicated that among the ZnONP, AgNP, the Cu NPs potentiate the bactericidal efficacy of CIP antibiotics. [ABSTRACT FROM AUTHOR]

Nowadays, the low hydrophobicity and separation efficiency of original electrospun carbon nanofiber (CF) membrane greatly limit its further application in the oil–water separation process. To address this problem, polydopamine (PDA) was coated on the surface of CF via dip-coating method, playing a role of chelation and reduction in the process of electroless plating, so as to deposit copper nanoparticles on the surface of nanofiber. Subsequently, 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane was used for fluorination treatment to successfully obtain superhydrophobic electrospun carbon nanofiber (F/Cu/PDA/CF) membrane. The results show that F/Cu/PDA/CF membrane has good water contact angle (WCA, 158.5°) and excellent separation performance. The separation efficiency of oil–water mixture and emulsion is greater than 99.4%. Furthermore, the F/Cu/PDA/CF membrane demonstrates good environmental stability under different conditions (high/low temperature, UV irradiation, and immersion in organic solvents). These results indicate that superhydrophobic F/Cu/PDA/CF membrane has great application potential in the treatment of oily wastewater. [ABSTRACT FROM AUTHOR]

The use of biosynthesis is considered an environmentally friendly and more sustainable method for the production of metal nanoparticles. In this study, copper nanoparticles (Cu-NPs) were synthesized using tea stem extract as a reducing agent. Spectroscopic identification revealed that the CuO is the major crystalline structure with a particle size of 14.9 nm. The Bg mode of the Raman active mode is associated with the symmetric oxygen stretching of Cu-O and is consistent with the monoclinic crystal CuO in X-ray powder diffraction (XRD) measurement. X-ray photoelectron spectrometer (XPS) deconvolution revealed the split peaks for Cu 2p3/2 and confirmed the coexistence of Cu+ and Cu2+ in the Cu-NPs. The Cu-NPs possessed effective catalytic ability for the degradation of methylene blue (MB) from the aqueous phase in a Fenton-like system. These results provide important evidence for the potential application of tea stem in synthesis of nanoparticle. [ABSTRACT FROM AUTHOR]

Eco-friendly copper nanoparticles (NPs) were prepared from the interaction of a cheap and accessible precursor, blue alum with biomolecules (polyphenols, flavonoids, proteins, terpenoids and organic sulfur compounds) in the garlic extract as the reducing of copper(II) ions, and its protector and stabilizer. As-synthesized Cu NPs were characterized by conventional methods such as XRD, UV-Vis, FT-IR, SEM, TEM, TGA and EDX. Observing the absorption maximum at the wavelength of 580 nm in the UV-Vis spectrum of the suspension solution indicated the formation of copper nanoparticles due to its surface plasma resonance. The results of the XRD diffraction pattern showed that the average size of copper crystallite was 65 nm. The morphology of the synthesized sample by scanning electron microscope (SEM) showed that copper NPs were irregular spherical. Transmission electron microscopy (TEM) estimated the average size of copper particles to be 70 nm. The as-synthesized copper NPs were used as a nano-catalyst in the reduction process of methylene blue (MB) by sodium borohydride (NaBH4). The results showed that by increasing the amount of copper NPs, the rate of methylene blue reduction reaction increased. By adding 0.0010 g of as-synthesized copper NPs to a solution containing 25 mL of methylene blue 20 ppm and 25 mL of sodium borohydride 200 ppm, it reduced time of the reaction from 4 hours to 2 minutes and its efficiency was 77%. The complete reaction time of 25 mL of methylene blue solution with concentrations of 30, 40 and 50 ppm by 25 mL of sodium borohydride 200 ppm in the presence of 0.0010 g of copper NPs took 15, 25 and 28 minutes, respectively. The effect of solution pH showed that in a certain amount of nanoparticles, the reduction rate of methylene blue was higher in an alkaline environment. [ABSTRACT FROM AUTHOR]

Electrochemical CO2 reduction is of tremendous interest for storing chemical energy from renewable sources while reducing CO2 emissions. While copper is one of the most effective catalysts, it suffers from low selectivity and limited long‐term durability. Here, these limitations are overcome by engineering Nafion coatings on CuO nanoparticle‐based catalysts supported on glassy carbon. By tuning the Nafion thickness and internal structure, it is shown that both the selectivity to multicarbon (C2+) products and long‐term stability can be dramatically enhanced. Optimized catalyst layers reach Faradaic efficiencies for C2+ products of 86% during long‐term testing for 200 h, with no evidence for performance degradation. Indeed, the C2+ Faradaic efficiency increases during testing, which is attributed to favorable in situ electrochemical fragmentation of catalytic nanoparticles. Finally, the optimized Nafion/Cu catalytic coatings are utilized to create scalable membrane electrode assemblies for CO2 electrolysis, yielding significantly enhanced C2H4 selectivity (≈58%) and activity at technologically‐relevant currents of 1–2 A. These results highlight the potential for creating multi‐functional Nafion coatings on CO2 reduction catalysts to favorably tune the reaction environment, while also promoting in situ transformations to active and selective nanoscale structures and morphologies, not just on model surfaces but also in state‐of‐the‐art gas diffusion electrodes. [ABSTRACT FROM AUTHOR]

AbstractCopper nanoparticles (CuNPs) were prepared using Iraqi Jasminum sambac (L.) Aiton. Substances identified by GC-MS to know pathway mechanism CuNPs synthesis. Characterization of CuNPs was done by UV-VIS at 420 nm, functional groups disclosed through FTIR, XRD broad chart in small CuNPs. Morphology and size of CuNPs were spherical in shape with an average size of less than 10 nm via TEM and FESEM, DLS appointed at 180.7 nm, good polydispersity at 0.24, and Z-potential analysis at −11.7 refer to stability. CuNPs against (Staphylococcus aureus) and (Escherichia coli) were actively compared with classical antibiotic drugs. An anticancer study that demonstrated in vitro cytotoxicity by MTT assay IC50 at 372 µg/mL against MCF-7, emphasized microscopic images of destroyed cells after exposure to CuNPs. Genotoxicity of cancer cells treating it as a signal to break down the DNA of targeted cancer cells (comet assay). Additionally, diminishing count DNA population of cells via flow cytometry. [ABSTRACT FROM AUTHOR]

The growth of material science and technology places a high importance on the creation of better processes for the synthesis of copper nanoparticles. So that, an easy, ecological, and benign process for producing copper nanoparticles (CuNPs) has been developed using candy leaf (Stevia rebaudiana) leaves aqueous extract for the first time. UV-visible spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), high-resolution transmission electron microscope (HR-TEM), Fourier transmission infrared (FTIR), and zeta potential were applied to demonstrate strong characterization for the biosynthesized stevia-CuNPs. The UV-visible absorbance at 575 nm of surface plasmon resonance (SPR) was 1.2. The particle size mean diameter was recorded as 362.3 nm with − 10.8 mV zeta potential. The HR-TEM scanning revealed 51.46–53.17 nm and spherical-shaped stevia-CuNPs surrounded by coat-shell proteins. The cytotoxicity and cytocompatibility activity assay revealed that stevia-CuNPs was safe in lower concentrations and had a significant cell viability reduction in higher concentrations. The produced stevia-CuNPs were applied as antimicrobial agents against eight pathogenic bacteria and five fungi strains. The inhibitory action of the stevia-CuNPs was more pronounced in bacteria than in fungi, and they likewise demonstrated further inhibition zones in Staphylococcus aureus (50.0 mm) than in Aspergillus flavus (55.0 mm). With inhibition zone sizes of 50.0 mm and 47.0 mm and 50 µg/ml minimum inhibitory concentration, S. aureus and A. flavus were the most inhibited pathogens. The minimum lethal effect (MLC) estimate for S. aureus was 50 µg/ml, whereas 75 µg/ml for A. flavus. The stevia-CuNPs mode of action was characterized as bactericidal/fungicidal as the ratio of MIC to MLC was estimated to be equal to or less than 2. After all, stevia-CuNPs could be used as an alternative to commercial antibiotics to solve the problem of multidrug-resistant (MDR) microorganisms. Key points: • Stevia-CuNPs in lower than 200 ug/ml concentrations are safe and tolerant for Vero normal cells. • Stevia-CuNPs has high antimicrobial activity which has a significant effect on various pathogenic bacteria. • Stevia-CuNPs has bactericidal/fungicidal mode of action for various pathogenic bacteria and fungi. [ABSTRACT FROM AUTHOR]

In this study, several electrospun nanofibers were prepared and characterized, and the electrospun polystyrene/poly-(ether sulfone) nanofiber coated with copper nanoparticles (PS/PES-CuNP nanofibers) was selected and utilized as solid-phase extraction adsorbent. And then, the packed-fiber solid-phase extraction coupled with high-performance liquid chromatography-fluorescence detection method was established for the efficient determination of ochratoxins in foods. With the proposed method, several factors including the type and dosage of nanofibers, sample pH, extraction time, type, and volume of elution solvent were optimized. The results suggested that low limit of detection (0.102–0.126 ng/mL), limit of quantification (0.382–0.436 ng/mL), and recoveries (85.5–111.1%) for ochratoxin A, B, and C with relative standard deviations <7% were achieved. As-synthesized PS/PES-CuNP nanofibers displayed satisfactory potential practical application in the simultaneous pretreatment and determination of mycotoxins in complex matrice samples. [ABSTRACT FROM AUTHOR]

In this study, mucilage was extracted from fenugreek seeds and essential oil from rosemary. The composite film of fenugreek seed mucilage and eggplant peel powder was prepared with copper nanoparticles (0, 2, 4%) and rosemary essential oil (0, 4, 8%). The physicochemical properties of the prepared films were investigated. According to the obtained results, with the increase of copper nanoparticles and rosemary essential oil, the thickness and antioxidant of the film increases. Humidity, water vapor permeability and solubility of the film decrease with the increase of copper nanoparticles and rosemary essential oil. Also, with the increase of copper nanoparticles and rosemary essential oil, the L* color indices increased and the brightness of the layers decreased significantly. Also, with the increase of copper nanoparticles, the color indices a* increased, but b* decreased. Also, with the increase of rosemary essential oil, the a* color indices have decreased, but the b* factor has increased. The results of antimicrobial activity showed that the addition of copper nanoparticles and rosemary essential oil made the film active against Staphylococcus aureus. Conclusion: The addition of copper nanoparticles and rosemary essential oil to edible films based on fenugreek seed mucilage and eggplant skin powder improved the thickness and antioxidant, solubility, moisture and permeability to water vapor, as well as weakening the brightness. [ABSTRACT FROM AUTHOR]

Copper nanoparticles (Cu‐NPs) have garnered substantial interest in the field of nanotechnology due to their exceptional physical and chemical properties and cost‐effectiveness. However, challenges such as particle aggregation and rapid copper oxidation affect nanoscale production. This study systematically investigates the synthesis of colloidal Cu‐NPs using chitosan (Cts) as a stabilizer and reducing agent in the arc discharge system, comparing it to distilled water as a medium. Confirmation of the purity, size, and morphology of the Cu‐NPs is achieved through various physicochemical characterization methods. X‐ray diffraction patterns confirm the synthesis of highly pure face‐centered cubic (fcc) crystal Cu‐NPs. UV–vis analysis reveals absorption peaks at 572–585 nm, indicating pure copper. Fourier‐transform infrared spectroscopy shows peaks at 638 and 597 cm−1, corresponding to Cu─Cts bonds. Transmission electron microscopy images depict spherical nanoparticles ranging from 15 to 45 nm, with smaller sizes at higher Cts concentrations. The catalytic activity of Cu‐NPs in the degradation of 4‐nitrophenol to 4‐aminophenol is assessed, with Cu‐NPs synthesized in distilled water demonstrating superior catalytic properties compared to 0.10 wt.% Cts. This study highlights the efficacy of the arc discharge method in producing pure, uniformly sized Cu‐NPs with potential applications in catalysis. [ABSTRACT FROM AUTHOR]

This study presents a green method of producing copper nanoparticles (CuNPs) using aqueous extracts from Sargassum spp. as reducing, stabilizing, and capping agents. The CuNPs created using this algae‐based method are not hazardous, they are eco‐friendly, and less toxic than their chemically synthesized counterparts. The XRD characterization of the CuNPs revealed the presence of Cu and CuO, with a crystallite size ranging from 13 to 17 nm. Following this, the CuNPs were supported onto a carbon substrate, also derived from Sargassum spp. (biochar CSKPH). The CuNPs in biochar (CuNPs‐CSKPH) did not appear in the XRD diffractograms, but the SEM‐EDS results showed that they accounted for 36 % of the copper weight. The voltamperometric study of CuNps‐CSKPH in acid media validated the presence of Cu and the amount was determined to be 2.58 μg. The catalytic activity of CuNPs‐CSKPH was analyzed for the electrochemical reduction of CO2. The use of Sargassum spp. has great potential to tackle two environmental problems simultaneously, by using it as raw material for the synthesis of activated biochar as support, as well as the synthesis of CuNPs, and secondly, by using it as a sustainable material for the electrochemical conversion of CO2. [ABSTRACT FROM AUTHOR]

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This study presents a green method of producing copper nanoparticles (CuNPs) using aqueous extracts from Sargassum spp. as reducing, stabilizing, and capping agents. The CuNPs created using this algae‐based method are not hazardous, they are eco‐friendly, and less toxic than their chemically synthesized counterparts. The XRD characterization of the CuNPs revealed the presence of Cu and CuO, with a crystallite size ranging from 13 to 17 nm. Following this, the CuNPs were supported onto a carbon substrate, also derived from Sargassum spp. (biochar CSKPH). The CuNPs in biochar (CuNPs‐CSKPH) did not appear in the XRD diffractograms, but the SEM‐EDS results showed that they accounted for 36 % of the copper weight. The voltamperometric study of CuNps‐CSKPH in acid media validated the presence of Cu and the amount was determined to be 2.58 μg. The catalytic activity of CuNPs‐CSKPH was analyzed for the electrochemical reduction of CO2. The use of Sargassum spp. has great potential to tackle two environmental problems simultaneously, by using it as raw material for the synthesis of activated biochar as support, as well as the synthesis of CuNPs, and secondly, by using it as a sustainable material for the electrochemical conversion of CO2. [ABSTRACT FROM AUTHOR]

The selective oxidation of methane under mild conditions remains the "Holy Grail of Catalysis". The key to activating methane and inhibiting over-oxidation of target oxygenates lies in designing active centers. Copper nanoparticles were loaded onto TiO2 nanofibers using the photo-deposition method. The resulting catalysts were found to effectively convert methane into C1 oxygenated products under mild conditions. Compared with previously reported catalysts, it delivers a superior performance of up to 2510.7 mmol·gCu−1·hr−1 productivity with a selectivity of around 100% at 80 °C for 5 min. Microstructure characterizations and density functional theory (DFT) calculations indicate that TiO2 in the mixed phase of anatase and rutile significantly increases the Cu+/Cu0 ratio of the supported Cu species, and this ratio is linearly related to the formation rate of oxygen-containing species. The Cu1 site promotes the generation of active O species from H2O2 dissociation on Cu2O (111). These active O species reduce the energy barrier for breaking the C–H bond of CH4, thus boosting the catalytic activity. The methane conversion mechanism was proposed as a methyl radical pathway to form CH3OH and CH3OOH, and then the generated CH3OH is further oxidized to HOCH2OOH. [ABSTRACT FROM AUTHOR]

Hazardous organic pollutants in industrial wastewaters are becoming a major global challenge that threatens life on earth and particularly poses a serious health risk to human beings. 4-Nitrophenol (4-NP) is a highly hazardous organic contaminant that has been extensively utilized across multiple industries, and their wastewater disposal into water streams leads to a higher accumulation of 4-NP. It is therefore important for both academia and industry to make catalysts that are cheap, very effective, good for the environment, easy to recover, and can be used more than once for reducing 4-NP in normal conditions. This paper reports the synthesis, characterization, and application of Cu/kaolin nanocomposite (NC) as an efficient heterogeneous catalyst for decomposing 4-NP, a model organic molecule. The catalyst was synthesized by incorporating a copper precursor into layered kaolin clay and directly reducing the metal precursor using sodium borohydride (NaBH4). The morphology, structure, surface property, and interaction of the resulting Cu/kaolin NC were characterized by ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron spectroscopy/energy-dispersive X-ray spectroscopy, selected area electron diffraction, X-ray diffraction, and N2 adsorption/desorption, and the results clearly demonstrated the growth of copper nanoparticles on the kaolin surface. It was discovered that the Cu nanoparticles (NPs) on the kaolin surface had a crystallite size of about 23.6 nm. The significance of Cu NPs and the high catalytic activity of the synthesized Cu/kaolin NC toward 4-NP reduction by NaBH4 were evaluated by the catalytic reduction experiments. Among the different nanocomposites synthesized, 30-Cu/kaolin showed the highest catalytic activity for 4-NP reduction, with a reduction efficiency of over 99 % within 4 min with a pseudo-first-order rate constant, kapp, of 1.23 min−1. Furthermore, the reusability test indicated that Cu/kaolin NC can be reused for up to six runs efficiently without significant decrease in its catalytic performance, indicating the nanocomposite has excellent stability and great potential applications in industrial and agricultural wastewater treatment.

Abstract The prevalence of the SARS‐CoV‐2 virus has led to an increased focus on cleaning and disinfecting surfaces in the community and hospitals. An inherently antibacterial thin film is reported to combat the transmission of microbes on glass surfaces that could be accessed by the public, reducing the need for constant cleaning. The copper nanoparticle thin film is synthesized via a sol–gel method and deposited using a dip‐coater to create a transparent, rugged film resistant to scratching. The antibacterial performance is tested by a droplet and an aerosol deposition technique, where Escherichia coli and Staphylococcus aureus are sprayed directly onto the thin film, replicating coughs and sneezes: a common form of microbial transmission. The mechanism of antibacterial performance is studied by introducing reactive oxygen species quenchers to the thin film. This research presents copper nanoparticle thin films as an effective solution in reducing the transmission of microbes on glass surfaces and their potential as a valuable tool in preventing the spread of infectious diseases.

Bionanofluids containing biological nanoparticles suspended in base fluids exhibit altered dynamics due to coupled effects between the nanoparticles and fluid properties. More efficient cooling can enhance medical technology performance, reduce energy usage, and provide safer, more sustainable healthcare solutions. This work overcomes previous research limitations by elucidating the combined impacts of microorganisms and couple stress properties on the behavior of water-based bionanofluids containing copper nanoparticles, under inclined magnetic fields. Governing equations for momentum, energy, concentration, and microorganisms are transformed into ordinary differential equations (ODEs) via similarity methods. The resulting ODE system is then solved semi-analytically using the Homotopy Analysis Method, revealing distinct profile behaviors. Additionally, quantitative indicators including skin friction for different values of M, λ,β, and Nr increased by 7.19%, 62.81%, 31.27%, and 21.32% respectively. Similarly Nusselt number for different values Qe , Ec, and Df decrease by 3.502 %, 2.5705%, and 2.447% respectively. Furthermore, Sherwood Numbers for different values of Sc, Kc, increased by 16.41%, and 4.133% respectively. Finally, Microorganisms for different values of Lb, Pe, and σ1 increase by 2.934%, 2.61%, and 1.172% respectively.

Background: Colon carcinoma poses a significant health challenge globally, particularly in developed nations where sedentary lifestyles, poor dietary choices, and genetic factors play a crucial role in its prevalence. Chemotherapy, the primary treatment method, carries severe side effects that can jeopardize patients' lives. Herbal extracts such as Ocimum Basillicum extract have shown effectiveness against cancer cells. Additionally, nanoparticles can significantly enhance drug delivery efficacy in these scenarios. Aim: This article aims to investigate the impact of copper nanoparticles coated with Ocimum Bassilicum at chemoradiotherapy of Colon Carcinoma to hopefully create new treatment options with fewer side effects for patients. Methodology: CuO bio-NPs were produced by the addition of 15 mL of extract dropwise to 80 mL of a 5 mM Cu (OAc)2 aqueous solution, which was then refluxed for 2 h at 100 °C. The mixture gradually became darker brown in color as a result of the heating procedure. The production of CuO NPs and the hydrogen-donating activity of antioxidant phenols within the plant are signaled by surface plasmon resonance excitation, which is the cause of this. In the cell culture, LS174t colon cancer cells were treated with OB extract, CuNPs, and OB-coated CuNPs with and without different radiation levels in order to assess cell viability, through the MTT assay, and the pro-apoptotic BAX and anti-apoptotic BCL2 expressions, through qPCR assay. Results: The results demonstrate a decrease in cell viability and the expression of BCL2 and an increase in the expression of BAX especially when treated with OB-coated CuNPs and even furthermore when paired with radiation therapy. Conclusions: After doing the clinical trial studies, the recent nanoparticles can be used for the treatment of Colorectal carcinoma.

In many underdeveloped countries, textile industries discharge their effluents without any treatment. The untreated textile wastewater consists of both azo dyes and heavy metals which not only change the physicochemical and biological properties of soil and water but also affect human health. In recent years, copper-based nanomaterials have attained worldwide attention because of their unique properties and potential for decolorization of azo dyes and wastewater treatment. The present study demonstrates the bacterial synthesis of copper nanoparticles (Cu-NPs) using Bacillus flexus strain isolated from a textile wastewater followed by their application for photocatalytic degradation of various azo dyes and treatment of actual wastewater. The FT-IR analysis confirmed the presence of various functional groups including proteins on Cu-NPs which improved their stability. The scanning electron microscopy (SEM) images revealed the spherical shape of Cu-NPs with a size of range between 17–34 nm. Similarly, the XRD analysis of biosynthesized Cu-NPs showed various diffraction peaks at 44.5°, 51.5°, 74.75 which confirmed the crystalline nature of nanoparticles. While studying the photocatalytic decolorization of azo dyes by Cu-NPs, it was observed that 88.164 ± 0.19 %, 88.452 ± 1.89 %, 90.433 ± 1.81 %, 64.770 ± 1.02 %, 46.774 ± 1.61 %, and 67.274 ± 2.89 % of reactive black-5, congo red, malachite green, methylene blue, reactive red-2 and blue direct, respectively, were decolorized after 4 h of solar irradiation at 50 ppm concentration. Additionally, the biosynthesized nanoparticles also resulted in reduction of various parameters like EC, pH, TDS, COD, color intensity, sulphates, and phosphates in the textiles wastewater. The reduction of COD, sulfates, and phosphates was about 39.659 %, 43.157 %, and 49.493 %. The results of current work suggest that biosynthesized copper nanoparticles might serve as a potential green solution for the decolorization of various dyes including wastewater treatment.

The development of copper nanoparticle (CuNP)-based catalysts for the electrochemical reduction of carbon dioxide (ECO2-R) offers a promising approach to enhance its transformation into other industrially significant compounds. This study reports ECO2-R at −1.3 V vs RHE using CuNPs and catalytic inks composed of CuNPs and ionic liquids (ILs), observing significant differences in the selectivity of each catalyst. Specifically, CuNPs alone show a preference for producing ethylene and aqueous products, such as formic acid, ethanol, and formaldehyde. In contrast, the addition of ILs to the catalytic system redirects selectivity toward gaseous products, with methane being the main product. These findings highlight the potential to optimize catalyst composition to tailor the selectivity of CO2 conversion processes. ILs modify the catalytic environment and influence reaction pathways, enabling the selection of specific products.

ASTM A106 B grade is used to manufacture seamless steel pipe, which can be used at high temperature, pressure, and hard environmental conditions for oil and gas supplies but suffers from corrosion. Polyurea is an organic coating that is resistant to moisture, UV light, and chemicals and has a high range of service temperatures. In this study, the effect of polyurea coating with the addition of copper nanoparticles was investigated for improvement of anti-corrosion and mechanical behavior in 3.5 % NaCl solution for A106 steel. Potentiodynamic Polarization (PDP) and Electrochemical Impedance Spectroscopy (EIS) tests were performed to examine anticorrosion properties, Scanning Electron Microscopy (SEM) was used to examine quality coating, thickness, and distribution of copper nanoparticles. Wear, hardness, and tensile tests were performed to check mechanical properties. The corrosion rate decreases from 0.16264 mpy to 0.01376 mpy while coating resistance increases from 2.95 × 104 Ω cm2 to 2.474 × 105 Ω cm2. An increasing trend was observed during the tensile test for pure polyurea and pure polyurea with 2 % copper nanoparticles. i.e., 501 MPa and 536 MPa, respectively. Results showed pure polyurea and polyurea with copper nanoparticles on steel improve its anti-corrosion and mechanical properties significantly.