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The paper reports on the preparation of cellulose nanocrystals/reduced graphene oxide matrix loaded with cuprous oxide nanoparticles (CNC/rGO‐Cu2O) through a simple solvothermal method and its application for 4‐nitrophenol reduction to 4‐aminophenol using sodium borohydride. The CNC/rGO‐Cu2O nanocomposite was formed chemically by first mixing CNC and graphene oxide (GO) followed by complexation of the negatively charged functional groups of CNC/GO with Cu2+ ions and subsequent heating at 100°C. This resulted in the simultaneous reduction of GO to rGO and the formation of Cu2O nanoparticles. The as‐elaborated nanocomposite was firstly characterized using different techniques such as atomic force microscopy, scanning electron microscopy, transmission electron microscopy, UV–Vis spectrophotometry, Raman spectroscopy and x‐ray photoelectron spectroscopy. Then, it was successfully applied for efficient catalytic reduction of 4‐nitrophenol to 4‐aminophenol using sodium borohydride: the reduction was completed in about 6 min. After eight times use, the catalyst still maintained good catalytic performance. Compared to CNC/rGO, rGO/Cu2O and free Cu2O nanoparticles, the CNC/rGO‐Cu2O nanocomposite exhibits higher catalytic activity even at lower copper loading. [ABSTRACT FROM AUTHOR]

This work describes a sustainable and efficient methodology for incorporating cuprous oxide nanoparticles into MIL-100(Fe) through functionalization with Cryptolepis buchanani Roem. & Schult extract, giving rise to a nanocomposite referred to as Cu2O@MIL-100(Fe). This composite provides a strategy for antimicrobial treatments and catalytic degradation of azo dye pollutants. The analysis delves into the physiochemical properties of the resulting composite materials, assessing their potential for antibacterial activity against both Gram-negative (Acinetobacter baumannii) and Gram-positive bacteria (Staphylococcus aureus), and their efficacy in catalyzing the decomposition of methyl orange dye. The successful integration of Cu2ONPs into MIL-100(Fe) was confirmed using transmission electron microscopy, scanning electron microscopy with energy dispersive X-ray spectroscopy, X-ray diffraction, and Brunauer–Emmett–Teller analysis. Functionalizing MIL-100(Fe) with the extract resulted in an average Cu2ONPs size of 4.28 ± 0.87 nm, exhibiting uniform distribution within the structure of MIL-100(Fe). DFT model calculations reveal the low-spin octahedral-site Fe3+ of MIL-100, which is favorable for binding to the phenolic compounds in the plant extract. Antibacterial activity tests indicated a significant enhancement in antibacterial properties, with minimum inhibitory concentrations of 1.5 and 3 mg mL−1 against Acinetobacter baumannii and Staphylococcus aureus, respectively. The synthesized Cu2O@MIL-100(Fe) exhibited effective catalytic activity in the degradation of methyl orange dye, with a pseudo-first-order rate constant ranging from 0.4237 to 0.5160 min−1, contingent upon the catalyst quantity, achieving complete degradation within 8 min. These findings provide valuable insights into the sustainable, non-toxic, and cost-effective synthesis process for Cu2ONPs, highlighting their potential as catalysts in water purification processes and as antimicrobial components in disinfectant formulations. [ABSTRACT FROM AUTHOR]

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A superior photoelectrochemical (PEC) aptasensor was manufactured for the detection of Escherichia coli (E. coli) based on a hybrid of triazine-based covalent–organic framework (COF) and cuprous oxide (Cu2O). The COF synthesized using 1,3,5-tris(4-aminophenyl)-benzene (TAPB) and 1,3,5-triformylphloroglucinol (Tp) as building blocks acted as a scaffold for encapsulated Cu2O nanoparticles (denoted as Cu2O@TAPB-Tp-COF), which then was employed as the bioplatform for anchoring E. coli-targeted aptamer. Cu2O@Cu@TAPB-Tp-COF demonstrated enhanced separation of the photogenerated carriers and photoabsorption ability and boosted photoelectric conversion efficiency. The developed Cu2O@TAPB-Tp-COF-based PEC aptasensor exhibited a lower detection limit of 2.5 CFU mL−1 toward E. coli within a wider range of 10 CFU mL−1 to 1 × 104 CFU mL−1 than most of reported aptasensors for determining foodborne bacteria, together with high selectivity, good stability, and superior ability and reproducibility. The recoveries of E. coli spiked into milk and bread samples ranged within 95.3–103.6% and 96.6–102.8%, accompanying with low RSDs of 1.37–4.48% and 1.74–3.66%, respectively. The present study shows a promising alternative for the sensitive detection of foodborne bacteria from complex foodstuffs and pathogenic bacteria-polluted environment. [ABSTRACT FROM AUTHOR]

The overuse of copper-based fertilizers and pesticides over the last few decades has resulted in detrimental risks to our environment. Nano-enabled agrichemicals with a high effective utilization ratio have shown great potential for maintaining or minimizing environmental issues in agriculture. Copper-based nanomaterials (Cu-based NMs) serve as a promising alternative to fungicides. Three types of Cu-based NMs with different morphologies were analyzed for their different antifungal effects on Alternaria alternata in this current study. Compared to commercial copper hydroxide water power (Cu(OH)2 WP), all tested Cu-based NMs, including cuprous oxide nanoparticles (Cu2O NPs), copper nanorods (Cu NRs) and copper nanowires (Cu NWs), especially Cu2O NPs and Cu NWs, showed higher antifungal activity against Alternaria alternata. Its EC50 were 104.24 and 89.40 mg L−1, respectively, achieving comparable activity using a dose approximately 1.6 and 1.9-fold lower. Cu-based NMs could introduce the downregulation of melanin production and soluble protein content. In contrast to trends in antifungal activity, Cu2O NPs showed the strongest power in regulating melanin production and protein content and similarly exhibited the highest acute toxicity to adult zebrafish compared to other Cu-based NMs. These results demonstrate that Cu-based NMs could offer great potential in plant disease management strategies. [ABSTRACT FROM AUTHOR]

Cuprous oxide nanoparticles (Cu2O) were synthesized by electrochemical method and as an add-on to construct polyethersulfone (PES) nanofiltration (NF) membranes. Field emission scanning electron microscopy (FESEM), 3D surface images, X-ray diffraction (XRD) analysis, and Fourier transform infrared (FTIR) spectroscopy were utilized to indicate membranes and nanoparticles. Membranes were evaluated by tests of water content, porosity, contact angle, salt rejection, water flux and average pore size measurements. The results show the enhancement of surface hydrophilicity by the addition of Cu2O nanoparticles. The highest unalloyed water flux was obtained by membrane, including 0.05 wt% Cu2O nanoparticles, and the highest rejection was revealed by a membrane containing 2 wt% Cu2O nanoparticles. The Na2SO4 rejection reached 66.94%, which was significantly higher than the bare PES membrane. This performance may be owing to increased Na2SO4 adsorption sites. The heavy metals rejection of CrSO4, Pb(NO3)2, and Cu (NO3)2 increased 79.38%, 85.08%, and 81% for the M5 membrane, respectively, while it was 45%, 46%, and 49% for bare membrane, respectively. Furthermore, the flux of unalloyed water increased from 9.78 L/m2·h on the pure PES membrane to 36.78 L/m2·h on the M1 membrane. The decrease of surface roughness and also the increase of hydrophilic groups improved the antifouling properties of the membranes. [ABSTRACT FROM AUTHOR]

The potential for the application of metal-containing nanomaterials at the nanoscale promotes the opportunity to search for new methods for their elaboration, with special attention to those sustainable methods. In response to these challenges, we have investigated a new method for green synthesis of cuprous oxide nanoparticles (Cu2O NPs) using Myrciaria dubia juice as an organic reductant and, comparing it with chemical synthesis, evaluating in both cases the influence of the volume of the organic (juice) and chemical (ascorbic acid) reductants, for which a large number of techniques such as spectrophotometry, EDX spectrometry, TEM, SEM, DLS, FTIR spectroscopy have been used. Likewise, the nanomaterial with better morphological characteristics, stability, and size homogeneity has been applied in the functionalization of textiles by means of in situ and post-synthesis impregnation methods. The success of the synthesis process has been demonstrated by the antimicrobial activity (bacteria and fungi) of textiles impregnated with Cu2O NPs.

Metal and metal oxide nanoparticles have gained huge interest due to their unique chemical and physical attributes that confer antimicrobial potential against a wide spectrum of pathogenic bacterial strains. Hence, the objective of the present study focused on synthesis of simple, cost-effective and environmentally friendly biofunctionalized cuprous oxide nanoparticles using root extract of Withania somnifera as antibacterial agents. The average size of the nanoparticles was found to be 410 nm with an energy band gap of 4.63 eV as confirmed by scanning electron microscopy and UV–visible spectroscopy, respectively. The chemical composition of the biofunctionalized Cu2O NPs was confirmed with the help of energy-dispersive X-ray analysis (EDAX). Vibrational studies of the cuprous oxide nanoparticles by Fourier transform infrared spectroscopy (FT-IR) gave a distinctive absorption band at 626 cm−1. The bactericidal effects of synthesized nanoparticles are attributed to different bioactive compounds, such as phthalic acid, purin-6-amine, hexadecanoic acid and benzene dicarboxylic acid, as analysed by gas chromatography–mass spectrometry (GC–MS). Finally, the antibacterial activities of cuprous oxide nanoparticles on Bacillus, Enterobacter, Escherichia and Mycobacterium were investigated by calculating the minimum bactericidal concentration (MBC) and colony forming unit (CFU) content by the broth dilution method. The biofunctionalized Cu2O NPs appeared to have strong antibacterial activity with 100% of inhibition against Escherichia coli, Enterobacter aerogenes and Mycobacterium smegmatis at MBC value 0.8 mg/ml whereas 100% inhibition against Bacillus subtilis at MBC value 1.0 mg/ml. The findings of our study suggest that the biofunctionalized Cu2O NPs coated with bioactive compounds from root extracts of Withania somnifera could be a promising antimicrobial agent for a wide range of pathogenic strains, especially Mycobacterium tuberculosis. [ABSTRACT FROM AUTHOR]

Copper oxide (Cu2O) is a promising semiconductor for photovoltaic and photocatalytic applications since this material has a high optical absorption coefficient and lower band gap (2.17 eV). Doped lanthanum (La), magnesium (Mg) and manganese (Mn) Cu2O nanoparticles (Cu2O Nps) were prepared by a displacement reaction. The doped and undoped Cu2O Nps were characterized with scanning electron microscopy–energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), transmission electron microscopy (TEM) and ultraviolet–visible spectroscopy. The EDS results confirm the presence of La, Mg and Mn in the Cu2O Nps. The XRD results confirm the formation a single cubic phase of Cu2O with a cuprite structure. TEM images confirm the formation of Nps with mean diameters between 12.0 ± 6.1 and 30.8 ± 11.0 nm. Doped and undoped Nps present a narrow band gap (2.40 eV), blue shifted with respect to bulk Cu2O.

Persulfate oxidation technology is widely used in wastewater treatment, but there are still many disadvantages, such as high energy consumption, side reaction and narrow pH applicability. Copper oxides can activate persulfate steadily with higher efficiency. In this paper, a novel preparation method of shape-controlled cuprous oxide (Cu2O) nanoparticles featured with high catalytic performance was explored. It was found that adding ionic liquid 1-butyl-3-methylimidazolium bromide ([BMIM]Br) during preparation of Cu2O can improve the degradation rate of diclofenac (DCF). Cu2O nanoparticles possess good stability in consecutive cycling tests, which was confirmed by X-ray photoelectron spectroscopy. The possible mechanism of Cu2O activating persulfate at different initial pH conditions was discussed based on electron paramagnetic resonance spin-trapping experiment. It was found that DCF was efficiently degraded in the Cu2O/peroxydisulfate (PDS) system within a broad pH range from 5 to 11. It proved via a quenching experiment that the activation process of PDS mainly occurs on the surface layer of Cu2O nanoparticles. As a result, shape-controlled Cu2O nanoparticles prepared by ionic liquid are expected to be used for in situ chemical oxidation, which is an effective oxidation processes to degrade DCF remaining in surface water and ground water. HIGHLIGHTS This study provides a novel preparation method of shape-controlled cuprous oxide (Cu2O) particles featured with high catalytic performance to degrade diclofenac (DCF).; It overcomes the disadvantages of degradation of organic pollutants by the traditional Fe in situ chemical oxidation system to some extent, such as being unrecyclable and having a narrow application range of pH value.;

To fight various bacteria‐caused inflammations and overcome drug resistance, the present work develops a simple in‐situ growth method to synthesize Cu2O nanoparticles involved nanocomposite using polyaniline (PANI) matrix. The morphology of the as prepared composite was characterized by Scanning Electron Microscope (SEM) and X‐ray Diffraction Spectroscopy (XRD), and the molecular structure was identified using Fourier‐Transforms Infrared FT‐IR, X‐ray Photoelectron Spectroscopy (XPS), and UV‐Visible Spectroscopy (UV‐Vis). The antibacterial properties of PANI/Cu2O nanocomposite were tested against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Methicillin‐resistant Staphylococcus aureus (MRSA). The combination of PANI and Cu2O indicated a synergistic antibacterial effect. The analysis of the antimicrobial mechanism revealed that the positive charge released from the nanocomposite takes the main responsibility. This work provides new ideas for the design of metal oxide and polymer nanocomposites and the development of antibiotics. [ABSTRACT FROM AUTHOR]

Cuprous oxide (Cu2O) nanoparticles at a loading of 33.5 wt.% were impregnated in amine-functionalized mesoporous silica (NH2-SBA-15) particles, by an in situ chemical reduction method. Subsequently, Cu2O-NH2-SBA-15 hybrid was used as a modifier of glassy carbon electrode (GCE) for making a non-enzymatic glucose sensor. The optimum composition of the modifier on the GCE surface (0.47 mg Cu in Cu2O-NH2-SBA-15/cm2 surface area of GCE) resulted in a wide linearity range (0.2–15 mM glucose) and a high sensitivity of 438.3 µAcm−2 mM−1, due to the high loading of Cu2O in NH2-SBA-15 host. Furthermore, glucose was detected both in normal range (5 mM) and in hypoglycaemic range (2 mM), selectively in presence of concentrations of interfering species typically found in the normal blood, such as sodium chloride (142 mM), potassium chloride (3.7 mM), urea (4.7 mM) and ascorbic acid (0.05 mM). The response time was also less than 5 s. Therefore, it achieved the desirable sensor characteristics, like linearity, sensitivity, selectivity, and speed of response. This better performance of the sensor is mainly attributed to a high electrocatalytic activity of Cu2O nanoparticles towards glucose. [ABSTRACT FROM AUTHOR]

The numerical study investigates the effect of various comparison criteria on the forced convective heat transfer of water-based cuprous oxide nanofluids in a horizontal mini tube under uniform heat flux conditions. The forced convective flow regime was validated, and it was ensured that the free convection effects were not present. The temperature-dependent thermophysical properties were considered for the numerical simulation. The volume concentrations of the nanofluids were kept below 2% (i.e., 0.6%, 1.3% and 1.9%) as higher concentrations lead to agglomeration and sedimentation of nanoparticles. The various comparison criteria employed for the assessment of heat transfer enhancement were equal pumping power, equal velocity, equal mass flow rate and equal Reynolds number criterion. The enhancements in heat transfer coefficient (at ϕv = 1.9% and base fluid Re = 1380) were 7.7%, 4.9%, 3.6% and 3.3% when assessed on the basis of equal Reynolds number, equal velocity, equal mass flow rate and equal pumping power, respectively. It was found that the enhanced heat transfer of the nanofluids should preferably be examined on the basis of equal pumping power criterion instead of above-mentioned other three criteria. The discussion on the invalidity of three evaluation criteria based on Reynolds number, velocity and mass flow rate has also been made. [ABSTRACT FROM AUTHOR]

Metal nanoparticles could be accumulated in soils, which threatens the ecological stability of crops. Investigating the effects of cuprous oxide nanoparticles (Cu 2 O-NPs) on photosystem Ⅱ (PSⅡ) of wheat seedling leaves holds considerable importance in comprehending the implications of Cu 2 O-NPs on crop photosynthesis. Following the hydroponic method, we investigated the effects of 0, 10, 50, 100, and 200 mg·L -1 Cu 2 O-NPs on chlorophyll fluorescence induction kinetics and photosynthetic-related genes in wheat seedlings of "Zhoumai 18". The results showed that, with the increases of Cu 2 O-NPs concentrations, chlorophyll contents in wheat leaves decreased, and the standardization of the OJIP curve showed a clearly K-phase (ΔK＞0). Cu 2 O-NPs stress increased the parameters of active PSⅡ reaction centers, including the absorption flux per active RC (ABS/RC), the trapping flux per active RC (TRo/RC), the electron transport flux per active RC (ETo/RC), and the dissipation flux per active RC (DIo/RC). Cu 2 O-NPs stress decreased the parameters of PSⅡ energy distribution ratio including the maximum quantum yield of PSⅡ ( φ Po ), the quantum yield of electron transport from QA ( φ Eo ), and the probability that a trapped exciton moved an electron further than QA ( Ψ o ), while increased the quantum ratio for heat dissipation ( φ Do ). Moreover, there was a decrease in photosynthetic quantum yield Y(Ⅱ), photochemical quenching coefficient ( q P ), net photosynthetic rate ( P n ), stomatal conductance ( g s ), intercellular CO 2 concentration ( C i ), and transpiration rate ( T r ) of leaves with the increases of Cu 2 O-NPs concentration. Under Cu 2 O-NPs stress, the expression levels of genes which included PSⅡ genes ( PsbD , PsbP , Lhcb1 ), Rubisco large subunit genes ( RbcL ), cytochrome b6/f complex genes ( PetD , Rieske ), and ATP synthase genes ( AtpA , AtpB , AtpE , AtpI ) were downregulated. These results indicated that Cu 2 O-NPs stress altered the activity and structure of PSⅡ in wheat seedlings, affected the activity of PSⅡ reaction centers, performance parameters of PSⅡ donor and acceptor sides. PSⅡ related genes were downregulated and exhibited significant concentration effects.

Herein, a feasible chemical reduction method followed by intensive mixing was applied for the preparation of an attractive material based on graphite studded with cuprous oxide nanoparticle-based cubes (Cu2ONPs–C@G). Transmission electron microscope (TEM), scanning electron microscope (SEM), X-ray diffraction (XRD) and cyclic voltammetry (CV) were utilized for characterization. Cuprous oxide nanoparticles (Cu2ONPs), with a diameter range mainly distributed from 4 to 20 nm, aggregate to form microcubes (Cu2ONPs–C) with an average diameter of about 367 nm. Paste electrode was prepared using Cu2ONPs–C@G (Cu2ONPs–C@G/PE) for voltametric quantification of the musculotropic antispasmodic drug: mebeverine hydrochloride (MEB). The electrochemical behavior of MEB was studied using CV, and the optimum analytical parameters were investigated using square wave adsorptive anodic stripping voltammetry (SWAdASV). Moreover, density functional theory (DFT) was used to emphasize the ability of MEB to form a complex with Cu2+, confirming the suggested electrochemical behavior of MEB at Cu2ONPs–C@G/PE. With good stability and high reproducibility, SWAdASV of Cu2ONPs–C@G/PE shows successful quantification of MEB over the concentration range of 5.00 × 10−11–1.10 × 10−9 M with lower limit of detection (LOD) and lower limit of quantification (LOQ) values of 2.41 × 10−11 M and 8.05 × 10−11 M, respectively. Finally, accurate quantification of MEB in dosage forms (tablets) and biological fluids (spiked human urine and plasma samples) was achieved using Cu2ONPs-C@G/PE.

Control and detection of sunset yellow is an utmost demanding issue, due to the presence of potential risks for human health if excessively consumed or added. Herein, cuprous oxide-electrochemically reduced graphene nanocomposite modified glassy carbon electrode (Cu2O-ErGO/GCE) was developed for the determination of sunset yellow. The Cu2O-ErGO/GCE was fabricated by drop-casting Cu2O-GO dispersion on the GCE surface following a potentiostatic reduction of graphene oxide (GO). Scanning electron microscope and X-ray powder diffractometer was used to characterize the morphology and microstructure of the modification materials, such as Cu2O nanoparticles and Cu2O-ErGO nanocomposites. The electrochemical behavior of sunset yellow on the bare GCE, ErGO/GCE, and Cu2O-ErGO/GCE were investigated by cyclic voltammetry and second-derivative linear sweep voltammetry, respectively. The analytical parameters (including pH value, sweep rate, and accumulation parameters) were explored systematically. The results show that the anodic peak currents of Cu2O-ErGO /GCE are 25-fold higher than that of the bare GCE, due to the synergistic enhancement effect between Cu2O nanoparticles and ErGO sheets. Under the optimum detection conditions, the anodic peak currents are well linear to the concentrations of sunset yellow, ranging from 2.0 x 10-8 mol/L to 2.0 x 10-5 mol/L and from 2.0 x 10-5 mol/L to 1.0 x 10-4 mol/L with a low limit of detection (S/N = 3, 6.0 x 10-9 mol/L). Moreover, Cu2O-ErGO/GCE was successfully used for the determination of sunset yellow in beverages and food with good recovery. This proposed Cu2O-ErGO/GCE has an attractive prospect applications on the determination of sunset yellow in diverse real samples. [ABSTRACT FROM AUTHOR]

A facile cuprous oxide nanoparticles functionalized electro-reduced graphene oxide modified glassy carbon electrode (denoted as Cu2O NPs-ERGO/GCE) was fabricated via a simple physical adsorption and electrochemical reduction approach. Cyclic voltammetry and second-order derivative linear scan voltammetry were used to investigate the electrocatalysis oxidation of vanillin on the Cu2O NPs-ERGO/GCE. The compound yielded a well-defined voltammetric response in 0.1M H2SO4 at 0.916 V (vs. saturated calomel electrode (SCE)). A linear calibration graph was obtained in the concentration range of 0.1 µM to 10 µM and 10 µM to 100 µM, while the detection limit (S/N = 3) is 10 nM. In addition, the Cu2O NPs-ERGO/GCE presented well anti-interference ability, stability, and reproducibility. It was used to detect vanillin sensitively and rapidly in different commercial food products, and the results were in agreement with the values obtained by high performance liquid chromatography. [ABSTRACT FROM AUTHOR]

The enhancement in the convective heat transfer coefficient of the ethylene glycol (EG) base cuprous oxide (CuO) nanofluids were investigated. The nanofluids of different volume concentrations i-e 1%, 2.5% and 4.5% were prepared by the two step method. Cuprous oxide (CuO) nanoparticles were ultrasonically stirred for four hours in the ethylene glycol (EG). The experimental study has been performed through circular tube geometry in laminar flow regime at average Reynolds numbers 36, 71 and 116. The constant heat flux Q = 4000 (W/m) was maintained during this work. Substantial enhancement was observed in the convective heat transfer coefficient of ethylene glycol (EG) base cuprous oxide (CuO) nanofluids than the base fluid. The maximum 74% enhancement was observed in convective heat transfer coefficient at 4.5 vol% concentration and Re = 116. [ABSTRACT FROM AUTHOR]

In this research, a facile and cost effective method is presented for in-situ synthesis of cuprous oxide nanoparticles on polyester fabric along with surface modification by using one pot wet chemical method at boil. Copper sulfate (CuSO), sodium hypophosphite (SHP) and polyvinylpyrrolidone (PVP) were used as precursor, reducing agent and stabilizer, respectively. Further, monoethanolamine (MEA) was used as pH adjustment and also modifier of polyester surface introduced amide and hydroxyl functional groups on the fabric. The images of FESEM, mapping, patterns of EDX, UV-visible absorbance spectrum, FTIR analysis and X-ray diffraction pattern confirmed the successful processing. The treated samples showed excellent antibacterial properties (100 %) toward both Staphylococcus aureus and Escherichia coli pathogen bacteria. Also, the results of cytotoxicity test proved no harmful effects on the human dermal fibroblasts for the treated sample with the lower concentration of the materials having white color with good antibacterial activities. The treated samples also indicated very good UV protection properties as well as improved wettability and mechanical properties. They are also sensitive to ammonia through immediate color change when contacted with ammonia solution. The above mentioned processing method can be used for production of polyester fabric with multifunctional properties for using in the various textile industries. [ABSTRACT FROM AUTHOR]

Objective To research the epithelial-mesenchymal transition (EMT) effects of cuprous oxide nanoparticles (CONPs) on melanoma. Methods Cuprous oxide nanoparticles were prepared hydrothermally.The B16 cells were cultured with cuprous oxide nanoparticlesat different concentrations (5,25,50 μg/ml).The changes of the morphology of the B16 cell were observed under the inverted microscope.The effects of CONPs on B16 cell migration ability were detected through the Wound healing assay and the Transwell assay.Then cell immunofluorescence and western blotting were used to test the EMT related molecular markers, including E-cadherin, N-cadherin, Cytokeratin, and Vimentin. Results The synthesized cuprous oxide nanoparticles distribute uniformly with a diameter of 40 nm.Our study indicated that CONPs inhibited the EMT of B16 cell.A conversion process was discovered in this study.In B16 cells, CONPs inhibited B16 cell migration, promoted the expression of E-cadherin, Cytokeratin and Desmoplakin, while the expression of N-cadherin and Vimentin was repressed in protein level. Conclusion Cuprous oxide nanoparticles can significantly restrain the invasion and metastasis of melanoma cells and inhabit the EMT of B16 cells. [ABSTRACT FROM AUTHOR]

CuO nanoparticle (NP)-functionalized cellulose-based aerogel (CuO/CBA) with three-dimensional (3D) macroporous structure and abundant active sites was successfully prepared for visible-light photocatalysis via in situ deposition of CuO NPs on cellulose-based aerogel (CBA). Octahedral CuO NPs were formed and anchored onto the surface and inner wall of the cellulose matrix, which acted as a microreactor to prevent aggregation and protect the catalytic character of the CuO NPs. The photocatalytic performance of the CuO/CBA composite catalysts was evaluated using degradation of methylene blue (MB) as model pollutant. The effects of catalyst dosage, initial MB concentration, and solution pH on MB photodegradation were investigated. Use of 3D macroporous CBA improved the MB adsorption capacity and extended the absorption of visible-light irradiation. In particular, in situ deposition of CuO in the cellulose matrix enhanced separation of photogenerated electrons and holes via surface-adsorbed molecular oxygen, and consequently the catalytic activity. The photodegradation rate of MB by CuO/CBA composite catalyst reached 95.79%, much higher than the value of 73.59% for pure CuO. The photodegradation process on the CuO/CBA composite catalysts followed an apparent pseudo-first-order kinetic model. The CuO/CBA composite catalyst was easily recycled and reused, with 80% MB degradation rate retained even after six cycles of irradiation for 30 min each. Such CuO/CBA composite catalysts can be applied for wastewater treatment utilizing solar radiation. [ABSTRACT FROM AUTHOR]

Nano-CuO particles were synthesized on cotton fabric using CuSO as a precursor and glucose as a reducing and capping agent in alkali. The morphology, crystal phase and chemical structure of the fabrics were characterized by scanning electron microscope, X-ray diffraction, Fourier transform infrared spectroscopy and energy-dispersive X-ray spectroscopy. The colorimetric values of the treated fabrics were also measured using reflectance spectra. The treated fabrics showed significant photocatalytic activity toward the degradation of methylene blue under daylight. Excellent antibacterial activity of the treated samples against Staphylococcus aureus and Escherichia coli was also confirmed. Moreover, treated fabrics were proven to have no adverse effects (low toxicity) on human dermal fibroblasts based on the MTT test. Findings suggested the potential of the proposed method in producing a fabric with high antibacterial efficiency, excellent self-cleaning properties, faster wetting time and negligible color change. Bleached cotton fabric treated with 0.02 w/w% copper sulfate and 0.35 w/w% glucose in alkali media (0.35 w/w% sodium hydroxide) at 70 °C for 1 h was found to be the optimum sample, with many applications in various fields including clothing, medical clothing and bedding. [ABSTRACT FROM AUTHOR]

Small molecular inhibitors in combination with or without interferon have improved sustained antiviral responses against Hepatitis C Virus (HCV) infection. Nonetheless, resistance to these inhibitors is expected to emerge rapidly due to the high mutation rate of the virus. Thus, new antiviral drugs, in combination with currently available therapies, are urgently needed to treat HCV infection. In the present study, we evaluated the antiviral efficacy of cuprous oxide nanoparticles (CO-NPs) against HCV in the HCVcc/Huh7.5.1 cell culture system. CO-NPs were able to significantly inhibit the infectivity of HCVcc at a non-cytotoxic concentration. In addition, CO-NPs inhibited the entry of HCV pseudoparticle (HCVpp), including genotypes 1a, 1b, and 2a, while no effect on HCV replication was observed. Further time-of-addition experiment indicated that CO-NPs blocked HCV infection both at the attachment and entry stages. In conclusion, we report that CO-NPs can act as an anti-HCV agent by targeting the binding of infectious HCV particles to hepatic cells and the virus entry into the cells. These findings suggest that CO-NPs may have novel roles in the treatment of patients with chronic hepatitis C. [ABSTRACT FROM AUTHOR]

An environmentally benign one-pot procedure has been developed for the syntheses of triazole-fused tetracyclic glycosides in aqueous medium. The two step one-pot synthesis involves Sonogashira reaction between azido-alkynes and aryl halides followed by intramolecular 1,3-dipolar cyclization using cubic cuprous oxide nanoparticles as reusable catalyst, under aerobic condition. The method excludes the use of any surfactants or additional ligands as stabilizing agents. The catalyst could be used up to three recycles without any loss of catalytic activity. The method has a broad perspective for the synthesis of medium size ring systems. [ABSTRACT FROM AUTHOR]

Nanopowders of copper (I) oxide (Cu 2 O, cuprite) were synthesized by out-of-phase pulsed sonoelectrochemical method and characterized by several physico-chemical techniques (X-ray diffraction, transmission electronic miscroscopy, energy-dispersive x-ray spectroscopy, centrifugal liquid sedimentation, zeta potentials and specific area measurements). The same analyses were done on commercial cuprite and copper nanopowders for comparison. Once the chemical nature and morphology of the three materials have been determined, bactericidal assays were performed on methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli) in Trypto-Casein-Soy medium. The results show that sonoelectrochemical Cu 2 O nanopowders are good antibacterial material as compared to the two commercial nanopowders while using a synthesis method that is inexpensive and adaptable to the industrial scale. [Display omitted] • Sonoelectrochemical Cu 2 O nanopowders are efficient bactericide materials in tryptocasein-soy. • Antibacterial activity is better against Staphylococcus aureus than Escherichia coli. • The nanopowder is bactericide at low mass concentration. [ABSTRACT FROM AUTHOR]

Highlights: [•] In situ synthesis of Cu2ONPs on cotton fabric with a simple and cost effective process. [•] High washing durability of treated fabric even after repeated washings. [•] Remarkable antibacterial effect on the treated cotton fabric. [•] Enhanced tensile strain and hydrophobicity of the treated cotton fabric. [•] Reversible optical sensing of ammonia and H2O2. [Copyright &y& Elsevier]

Cuprous oxide nanoparticles (CuO NPs) possess unique physical and chemical properties which are employed in a broad variety of applications. However, little is known about the adverse effects of CuO NPs on organisms. In the current study, in vitro cytotoxicity of CuO NPs (ca. 60 nm in diameter) to the blood cells of freshwater fish Carassius auratus was evaluated. A concentration-dependent hemolytic activity of CuO NPs to red blood cells (RBCs) and the phagocytosis of CuO NPs by leukocytes were revealed. The results showed that dosages of CuO NPs greater than 40 μg/mL were toxic to blood cells, and could cause serious membrane damage to RBCs. The EC value of CuO NPs as obtained from RBCs and whole blood exposure was 26 and 63 μg/mL, respectively. The generation of reactive oxygen species and the direct interaction between CuO NPs and the cell membrane were suggested as the possible mechanism for cytotoxicity, and the intrinsic hemolytic active of CuO NPs was the main contributor to the toxicity rather than solubilized copper ions. The adsorption of plasma proteins on the surfaces of CuO NPs led to their aggregation in whole blood, and aggregate formation can significantly alleviate the hemolytic effect and subsequently mediate the phagocytosis of CuO NPs by leukocytes. [ABSTRACT FROM AUTHOR]

In this study, cuprous oxide nanoparticles of 30–50 nm in size were prepared in the presence of cetyltrimethylammonium bromide (CTAB). By taking Staphylococcus aureus ( S.a), which always causes a variety of suppurative infections and toxinoses in humans, as a model bioparticle, the negative bioeffect of nano-Cu2O on S.a cells was evaluated, and minimal inhibitory concentration (MIC) was determined by imitating the MIC of antibiotics. Cellularity and bactericidal effect were measured by flow cytometry (FCM), dark field light scattering imaging and SEM photography. The results showed that nano-Cu2O particles may, by absorbing on the cell surface, impair the cell wall, damage the cell membrane, and finally increase permeability of the cell membrane, thus leading to a decrease in the viability of bacteria in the nano-Cu2O solution. [ABSTRACT FROM AUTHOR]

Abstract: Zeolite framework stabilized copper(I) oxide nanoparticles (4.8±2.6 nm) were prepared for the first time by using a four step procedure: the ion exchange of Cu2+ ions with the extra framework Na+ ions in Zeolite-Y, the reduction of the Cu2+ ions within the cavities of zeolite with sodium borohydride in aqueous solution, the dehydration of Zeolite-Y with the copper(0) nanoclusters, and the oxidation of intrazeolite copper(0) nanoclusters by O2 at room temperature. Zeolite stabilized copper(I) oxide nanoparticles were thoroughly characterized by ICP-OES, XRD, HR-TEM, Raman, XPS, UV–vis spectroscopy and N2 adsorption–desorption technique. [Copyright &y& Elsevier]

Herein, a feasible chemical reduction method followed by intensive mixing was applied for the preparation of an attractive material based on graphite studded with cuprous oxide nanoparticle-based cubes (Cu2ONPs–C@G). Transmission electron microscope (TEM), scanning electron microscope (SEM), X-ray diffraction (XRD) and cyclic voltammetry (CV) were utilized for characterization. Cuprous oxide nanoparticles (Cu2ONPs), with a diameter range mainly distributed from 4 to 20 nm, aggregate to form microcubes (Cu2ONPs–C) with an average diameter of about 367 nm. Paste electrode was prepared using Cu2ONPs–C@G (Cu2ONPs–C@G/PE) for voltametric quantification of the musculotropic antispasmodic drug: mebeverine hydrochloride (MEB). The electrochemical behavior of MEB was studied using CV, and the optimum analytical parameters were investigated using square wave adsorptive anodic stripping voltammetry (SWAdASV). Moreover, density functional theory (DFT) was used to emphasize the ability of MEB to form a complex with Cu2+, confirming the suggested electrochemical behavior of MEB at Cu2ONPs–C@G/PE. With good stability and high reproducibility, SWAdASV of Cu2ONPs–C@G/PE shows successful quantification of MEB over the concentration range of 5.00 × 10−11–1.10 × 10−9 M with lower limit of detection (LOD) and lower limit of quantification (LOQ) values of 2.41 × 10−11 M and 8.05 × 10−11 M, respectively. Finally, accurate quantification of MEB in dosage forms (tablets) and biological fluids (spiked human urine and plasma samples) was achieved using Cu2ONPs-C@G/PE. [ABSTRACT FROM AUTHOR]

• Cu(I)@MIL-101(Cr) composite was evaluated for propane/propylene separation. • Embedding the nanoparticles increased the propylene selectivity from 1.5 to 12.2. • 12%Cu@MIL-101(Cr) showed the optimum performance among all the synthesized samples. • The isothermal micropore model was capable to predict the transient uptake curves. The performance of the MIL-101(Cr) loaded with cuprous oxide (Cu 2 O) nanoparticles was evaluated in both equilibrium and kinetic conditions for adsorption of propane and propylene via volumetric method. The single-component adsorption isotherms were measured at temperatures of 303, 323, 343 and 363 K and pressures up to 400 kPa. To correlate the experimental isotherm data points, temperature-dependent Sips model was applied, which exhibited high accuracy of prediction. The synthesized samples were characterized by XRD, BET, FE-SEM, EDS mapping and TEM techniques. The binary mixture adsorption behavior and selectivity of propane/propylene were calculated by using the ideal adsorbed solution theory (IAST). Obtained results showed that by increasing the loading of Cu 2 O nanoparticles up to 15 wt%, the propylene selectivity of MIL-101(Cr) was enhanced from 1.5 to 12.2 at 100 kPa and 303 K. Moreover, the optimum performance in terms of both adsorption capacity and selectivity was achieved using 12%Cu@MIL-101(Cr) sample. Fast diffusion of the adsorbates, obtained by accurate fitting of the isothermal micropore model to the uptake curves data, along with reusability suggest the 12%Cu@MIL-101(Cr) as a promising adsorbent for effective separation of propane/propylene mixture. [ABSTRACT FROM AUTHOR]

In this study, we synthesized a non-precious Cu 2 O decorated reduced graphene oxide composite (Cu 2 O/rGO) by a facile and direct reduction strategy and evaluated the electricity generation and COD removal performance of MFCs with Cu 2 O/rGO as cathode catalyst in treating cattle wastewater. The Cu 2 O/rGO with the mass Cu(Ac) 2 /GO ratio of 450:50 exhibited the highest catalytic activity by cyclic voltammetry (CV) experiment. The large surface area (363.9 m2 g−1) of Cu 2 O/rGO with numerous mesoporous exhibited higher exchange current density (12.38 μA cm−2) and lower War-burg impedance (21.82 Ω) comparing with Pt/C (11.99 μA cm−2, 102.10 Ω), and contributed to 4-electron ORR. Notably, the maximum output voltage, power density and coulombic efficiency of MFC with 3D air cathode employed Cu 2 O/rGO catalyst reached 0.165 V, 1362 mW m−2 and 54.9%, respectively, which were higher than those (0.152 V, 1166 mW m−2 and 53.5%) with 3D air cathode employed Pt/C catalyst in treating cattle wastewater. Moreover, the average COD removal rate of MFC with Cu 2 O/rGO catalyst reached 71.5%, which were higher than those 69.8% with Pt/C catalyst. Generally, the MFC with 3D air cathode employed non-precious Cu 2 O/rGO catalyst instead of Pt/C catalysts is a promising method for simultaneous electricity generation and cattle wastewater treatment. • Cu 2 O nanoparticles/rGO cathode catalyst was synthesized for ORR in MFC. • Cu 2 O/rGO with mass Cu(Ac) 2 /GO ratio of 450:50 had the highest catalytic activity. • Structural characterization and electrocatalytic property of Cu 2 O/rGO were explored. • Electricity generation and COD removal from cattle wastewater in MFCs were evaluated. [ABSTRACT FROM AUTHOR]

Cuprous oxide nanoparticles (Cu2ONPs) were used for preparing composites with linear low-density polyethylene (LLDPE) by co-extrusion, thermal adhesion, and attachment using ethyl cyanoacrylate, trimethoxyvinylsilane, and epoxy resin. The composites were examined by Scanning electron microscope and tested for their antibacterial activity against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. All of these composites—except for the one obtained by extrusion—eradicated cells of both bacteria within half an hour. The composite prepared by thermal adhesion of Cu2ONPs on LLDPE had the highest external exposure of nanoparticles and exhibited the highest activity against the bacteria. This composite and the one obtained using ethyl cyanoacrylate showed no leaching of copper ions into the aqueous phase. Copper ion leaching from composites prepared with trimethoxyvinylsilane and epoxy resin was very low. The antibacterial activity of the composites can be rated as follows: obtained by thermal adhesion > obtained using ethyl cyanoacrylate > obtained using trimethoxyvinylsilane > obtained using epoxy resin > obtained by extrusion. The composites with the highest activity are potential materials for tap water and wastewater disinfection. [ABSTRACT FROM AUTHOR]

Recent studies have shown that metal and metal oxide have a potential function in antitumor therapy. Our previous studies demonstrated that cuprous oxide nanoparticles (CONPs) not only selectively induce apoptosis of tumor cells in vitro but also inhibit the growth and metastasis of melanoma by targeting mitochondria with little hepatic and renal toxicities in mice. As a further study, our current research revealed that CONPs induced apoptosis of human melanoma stem cells (CD271 +/high cells) in A375 and WM266-4 melanoma cell lines and could significantly suppress the expression of MITF, SOX10 and CD271 involved in the stemness maintenance and tumorigenesis of melanoma stem cells. CD271 +/high cells could accumulate more CONPs than CD271 -/low through clathrin-mediated endocytosis. In addition, lower dosage of CONPs exhibited good anti-melanoma effect by decreasing the cell viability, stemness and tumorigenesis of A375 and WM266-4 cells through reducing the expression of SOX10, MITF, CD271 and genes in MAPK pathway involved in tumor progression. Finally, CONPs obviously suppressed the growth of human melanoma in tumor-bearing nonobese diabetic-severe combined immunodeficiency (NOD-SCID) mice, accompanied with tumors structural necrosis and fibrosis remarkably and decreased expression of CD271, SOX10 and MITF. These results above proved the effectiveness of CONPs in inhibiting melanoma progress through multiple pathways, especially through targeting melanoma stem cells., Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Aim: To investigate the biological fate of cuprous oxide nanoparticles (Cu2O-NPs) and to evaluate their potential in uveal melanoma therapy., Materials & Methods: The protein corona, cellular uptake mechanism and localization of Cu2O-NPs were investigated. Furthermore, the effect of Cu2O-NPs on uveal melanoma cell proliferation, migration and invasion, and possible mechanisms were studied in detail., Results: Cu2O-NPs are able to adsorb serum proteins in cell culture medium, which are then internalized by uveal melanoma cells mainly through lipid raft-mediated endocytosis. Furthermore, Cu2O-NPs selectively inhibit cancer cell growth and impair the ability of uveal melanoma cell migration, invasion and the cytoskeleton assembly. The mechanism may be that Cu2O-NPs located in and damage mitochondria, autophagolysosomes and lysosomes, leading to elevated reactive oxygen species level and over-stimulated apoptosis and autophagy., Conclusion: The data provide detailed information of Cu2O-NPs for further application and indicate that Cu2O-NPs could be a potential agent for uveal melanoma therapy.