Biosurfactant-capped CuO nanoparticles coated cotton/polypropylene fabrics toward antimicrobial textile applications.

The global COVID-19 pandemic has led to an increase in the importance of implementing effective measures to prevent the spread of microorganisms. Consequently, there is a growing demand for antimicrobial materials, specifically antimicrobial textiles and face masks, because of the surge in diseases caused by bacteria and viruses like SARS-CoV-2. Face masks that possess built-in antibacterial properties can rapidly deactivate microorganisms, enabling reuse and reducing the incidence of illnesses. Among the numerous types of inorganic nanomaterials, copper oxide nanoparticles (CuO NPs) have been identified as cost-effective and highly efficient antimicrobial agents for inactivating microbes. Furthermore, biosurfactants have recently been recognized for their potential antimicrobial effects, in addition to inorganic nanoparticles. Therefore, this research's primary focus is synthesizing biosurfactant-mediated CuO NPs, integrating them into natural and synthetic fabrics such as cotton and polypropylene and evaluating the resulting fabrics' antimicrobial activity. Using rhamnolipid (RL) as a biosurfactant and employing a hydrothermal method with a pH range of 9-11, RL-capped CuO NPs are synthesized (RL-CuO NPs). To assess their effectiveness against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) microorganisms, the RL-CuO NPs are subjected to antibacterial testing. The RL-capped CuO NPs exhibited antimicrobial activity at much lower concentrations than the individual RL, CuO. RL-CuO NPs have shown a minimum inhibitory concentration (MIC) of 1.2 mg ml-1and minimum bactericidal concentration (MBC) of 1.6 mg ml-1forE. coliand a MIC of 0.8 mg ml-1and a MBC of 1.2 mg ml-1forS. aureus, respectively. Furthermore, the developed RL-CuO NPs are incorporated into cotton and polypropylene fabrics using a screen-printing technique. Subsequently, the antimicrobial activity of the coated fabrics is evaluated, revealing that RL-CuO NPs coated fabrics exhibited remarkable antibacterial properties against both gram-positive and gram-negative bacteria.

Toxic mechanism in Daphnia magna due to phthalic acid esters and CuO nanoparticles co-exposure: The insight of physiological, microbiomic and metabolomic profiles.

Various phthalic acid esters (PAEs) such as dibutyl phthalate (DBP) and butyl benzyl phthalate (BBP) co-exist with nanopollutants in aquatic environment. In this study, Daphnia magna was exposed to nano-CuO and DBP or BBP at environmental relevant concentrations for 21-days to investigate these combined toxic effects. Acute EC50 values (48 h) of nano-CuO, DBP, and BBP were 12.572 mg/L, 8.978 mg/L, and 4.785 mg/L, respectively. Results showed that co-exposure with nano-CuO (500 µg/L) for 21 days significantly enhanced the toxicity of DBP (100 µg/L) and BBP (100 µg/L) to Daphnia magna by 18.37% and 18.11%, respectively. The activities of superoxide dismutase, catalase, and glutathione S-transferase were enhanced by 10.95% and 14.07%, 25.63% and 25.91%, and 39.93% and 35.01% in nano-CuO+DBP and nano-CuO+BBP treatments as compared to the individual exposure groups, verifying that antioxidative defense responses were activated. Furthermore, the co-exposure of nano-CuO and PAEs decreased the population richness and diversity microbiota, and changed the microbial community composition in Daphnia magna. Metabolomic analysis elucidated that nano-CuO + PAEs exposure induced stronger disturbance on metabolic network and molecular function, including amino acid, nucleotides, and lipid metabolism-related metabolic pathways, as comparison to PAEs single exposure treatments. In summary, the integration of physiological, microflora, and untargeted metabolomics analysis offers a fresh perspective into the potential ecological risk associated with nanopollutants and phthalate pollution in aquatic ecosystems.

CuO Nanoparticles Reduce Toxicity and Enhance Bioaccumulation of Cadmium and Lead in the Cells of the Microalgae Desmodesmus communis.

The removal of pollutants, including heavy metals, from the aquatic environment is an urgent problem worldwide. Actively developing nanotechnology areas is becoming increasingly important for solving problems in the field of the remediation of aquatic ecosystems. In particular, methods for removing pollutants using nanoparticles (NPs) are proposed, which raises the question of the effect of a combination of NPs and heavy metals on living organisms. In this work, we investigated the role of CuO-NPs in changing the toxicity of Cd and Pb salts, as well as the bioaccumulation of these elements in a culture of the microalga Desmodesmus communis. It was found that CuO-NPs at concentrations of 10, 100, and 1000 µg L-1 had no effect on the viability of microalgae cells. On the 14th day of the experiment, Cd at a concentration of 1 mg L-1 reduced the viability index by 30% and, when combined with CuO-NPs, by 25%, i.e., CuO-NPs slightly reduced the toxic effect of Cd. At the same time, in this experiment, when CuO-NPs and Cd were used together, the level of oxidative stress increased, including on the first day in mixtures with 1 mg L-1 Cd. Under the influence of Pb, the cell viability index decreased by 70% by the end of the experiment, regardless of the metal concentration. The presence of CuO-NPs slightly reduced the toxicity of Pb in terms of viability and reactive oxygen species (ROS). At the same time, unlike Cd, Pb without NPs caused ROS production on the first day, whereas the addition of CuO-NPs completely detoxified Pb at the beginning and had a dose-dependent effect on mixtures at the end of the experiment. Also, the introduction of CuO-NPs slightly reduced the negative effect of Pb on pigment synthesis. As a molecular mechanism of the observed effects, we prioritized the provocation of oxidative stress by nanoparticles and related gene expression and biochemical reactions of algae cells. Analysis of the effect of CuO-NPs on the Cd and Pb content in microalgae cells showed increased accumulation of heavy metals. Thus, when algae were cultured in an environment with Cd and CuO-NPs, the Cd content per cell increased 4.2 times compared to the variant where cells were cultured only with Cd. In the case of Pb, the increase in its content per one cell increased 6.2 times when microalgae were cultured in an environment containing CuO-NPs. Thus, we found that CuO-NPs reduce the toxic effects of Cd and Pb, as well as significantly enhance the bioaccumulation of these toxic elements in the cells of D. communis microalgae. The results obtained can form the basis of technology for the nanobioremediation of aquatic ecosystems from heavy metals using microalgae.

Lettuce (Lactuca sativa L.) alters its metabolite accumulation to cope with CuO nanoparticles by promoting antioxidant production and carbon metabolism.

Copper-based nanoparticles (NPs) are gradually being introduced as sustainable agricultural nanopesticides. However, the effects of NPs on plants requires carefully evaluation to ensure their safe utilization. In this study, leaves of 2-week-old lettuce (Lactuca sativa L.) were exposed to copper oxide nanoparticles (CuO-NPs, 0 [CK], 100 [T1], and 1000 [T2] mg/L) for 15 days. A significant Cu accumulation (up to 1966 mg/kg) was detected in lettuce leaves. The metabolomics revealed a total of 474 metabolites in lettuce leaves, and clear differences were observed in the metabolite profiles of control and CuO-NPs treated leaves. Generally, phenolic acids and alkaloids, which are important antioxidants, were significantly increased (1.26-4.53 folds) under foliar exposure to NPs; meanwhile, all the significantly affected flavonoids were down-regulated after CuO-NP exposure, indicating these flavonoids were consumed under oxidative stress. Succinic and citric acids, which are key components of the tricarboxylic acid cycle, were especially increased under T2, suggesting the energy and carbohydrate metabolisms were enhanced under high-concentration CuO-NP treatment. There was also both up- and down-regulation of fatty acids, suggesting cell membrane fluidity and function responded to CuO-NPs. Galactinol, which is related to galactose metabolism, and xanthosine, which is crucial in purine and caffeine metabolism, were down-regulated under T2, indicating decreased stress resistance and disturbed nucleotide metabolism under the high CuO-NP dose. Moreover, the differentially accumulated metabolites were significantly associated with plant growth and its antioxidant ability. Future work should focus on controlling the overuse or excessive release of NPs into agricultural ecosystems to limit their adverse effects.

Anti-capsular activity of CuO nanoparticles against Acinetobacter baumannii produce efflux pump.

Copper oxide nanoparticles are modern kinds of antimicrobials, which may get a lot of interest in the clinical application. This study aimed to detect the anti-capsular activity of CuO nanoparticles against Acinetobacter baumannii produce efflux pump. Thirty-four different clinical A. baumannii isolates were collected and identified by the phenotypic and genetic methods by the recA gene as housekeeping. Antibiotic sensitivity and biofilm-forming ability, capsular formation were carried out. The effect of CuO nanoparticles on capsular isolates was detected, the synergistic effects of a combination CuO nanoparticles and gentamicin against A. baumannii were determined by micro broth checkerboard method, and the effect of CuO nanoparticles on the expression of ptk, espA and mexX genes was analyzed. Results demonstrated that CuO nanoparticles with gentamicin revealed a synergistic effect. Gene expression results show reducing the expression of these capsular genes by CuO nanoparticles is major conduct over reducing A. baumannii capsular action. Furthermore, results proved that there was a relationship between the capsule-forming ability and the absence of biofilm-forming ability. As bacterial isolates which were negative biofilm formation were positive in capsule formation and vice versa. In conclusion, CuO nanoparticles have the potential to be used as an anti-capsular agent against A. baumannii, and their combination with gentamicin can enhance their antimicrobial effect. The study also suggests that the absence of biofilm formation may be associated with the presence of capsule formation in A. baumannii. These findings provide a basis for further research on the use of CuO nanoparticles as a novel antimicrobial agent against A. baumannii and other bacterial pathogens, also to investigate the potential of CuO nanoparticles to inhibit the production of efflux pumps in A. baumannii, which are a major mechanism of antibiotic resistance.

The Toxic Effects of Cu and CuO Nanoparticles on Euplotes aediculatus.

The single-celled eukaryote Euplotes aediculatus was chosen to test and compare the toxic effects of Cu and CuO nanoparticles (NPs). The antioxidant enzymatic activity, morphological changes, and functional groups on the membrane were determined using spectrophotometry, microscopy, and Fourier transform infrared spectroscopy after NPs treatment. The toxicity of the NPs to cells was dose-dependent, and the 24 h-LC50 values of the CuNPs and CuONPs were 0.46 µg/L and 1.24 × 103 µg/L, respectively. These NPs increased the activities of superoxide dismutase, glutathione peroxidase, and catalase and destroyed the cell structure; moreover, the CuNPs were more toxic than the CuONPs. In addition to the higher enzymatic activity, CuNPs also caused nucleoli disappearance, chromatin condensation, and mitochondrial and pellicle damage. The oxidization of the functional groups of the membrane (PO2 - , C-O-C, and δ(COH) of carbohydrates) also confirmed the severe damage caused by CuNPs. Our study showed that oxidative stress and organelle destruction played important roles in the toxic effects of these NPs on this protozoan. Compared with other aquatic organisms, E. aediculatus can be considered a potential indicator at the preliminary stage of environmental pollution.

Enhanced photocatalytic activity and antiviral evaluation of CuO@Fe2O3NC for amoxicillin degradation and SARS-CoV-2 treatment.

Copper oxide nanoparticles (CuO NPs) and CuO NPs decorated with hematite (Fe2O3) nanocomposites (CuO@Fe2O3NC) were biosynthesized by a green method usingPortulaca oleracealeaves extract. The NC were characterized using various techniques, including x-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive x-ray spectroscopy, and UV-vis spectroscopy. The results showed that the synthesized CuO and CuO@Fe2O3NC were crystalline with a monoclinic crystal structure and contained functional groups responsible for catalytic activity. The size of the nanocomposites ranged from 39.5 to 45.9 nm, and they exhibited a variety of agglomerated or aggregated shapes. The CuO@Fe2O3NC showed improved photocatalytic activity for the degradation of antibiotics in water and wastewater and promising antiviral activity against SARS-CoV-2, indicating its potential for use in disinfection applications. The study investigated the impact of irradiation time on the photocatalytic degradation of Amoxicillin and found that increasing the irradiation time led to a higher degradation rate. The band gap energy (Eg) for pure CuO NPs was around 2.4 eV and dropped to 1.6 eV with CuO@Fe2O3NC. In summary, the CuO@Fe2O3NC has the potential to be an efficient photocatalyst and promising antiviral agent for environmental remediation. The CuO@Fe2O3nanocomposites have been found to possess a high degree of efficacy in inactivating SARS-CoV-2 infectivity. The results of the study indicate that the nanocomposites exhibit potent anti-viral properties and hold significant potential for use in mitigating the spread of the virus.

Genesis of copper oxide nanoparticles from waste printed circuit boards and evaluation of their photocatalytic activity.

Discarded Printed Circuit Boards (PCBs) are one of the secondary resources of high-purity copper, and precious materials, which if disposed off inappropriately may present several environmental risks. This study focuses on the production of copper oxide nanoparticles (CuO NPs) from reclaimed copper via a facile precipitation route to obtain a value-added nanoproduct. The synthesis involved the dissolution of downsized PCBs, leaching of Cu into the solution phase and the precipitation of nanoparticles (NPs) in an alkaline medium. XRD analysis confirmed the as-synthesized NPs were monoclinic CuO of size 19.23 nm without any impurity. HRTEM analysis confirmed that the NPs were nearly round spheres with average particle size of 19.973 ± 6.036 nm. The NPs have a specific surface area of 200 m2/g and mesoporous structure with mean pore diameter of 18.051 nm. The CuO NPs photocatalyzed the degradation of Congo Red under visible light irradiation. Hence, the PCB e-waste was utilized to produce nanomaterials with added-values, decreasing environmental problems.

Biogenic preparation of copper oxide nanoparticles using table olive: Catalytic reduction, cytotoxicity, and burn wound healing activities.

Green strategy for the preparation of copper oxide nanoparticles (CuO NPs) using table olive has been researched in the present work. Some characterization assays viz., transmission electron microscopy (TEM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) was used for evaluation of the crystal structure, size and morphology of the manufactured NPs. As a catalyst, the prepared material demonstrated remarkable catalytic capability (>99% in 4 min) for the reduction of rhodamine B using sodium borohydride. In addition, the treated cells with the CuO NPs were examined by regarding the cytotoxicity properties on normal (HUVEC) cell line. The results showed that the prepared CuO NPs did not have any cytotoxicity effects on HUVEC (up to 500 µg/mL). Furthermore, in vivo experiments on burn wounds in rats show that the synthesized CuO NPs ointment significantly diminished (p ≤ 0.01) the wound area. On the other hand, the wound contracture factor was increased in comparison with the control groups. Collectively, the CuO NPs prepared by biological method have potential applications in organic pollutants reduction and wound care applications. In this viewpoint, CuO NPs may be considered as an effective for treatment of different wounds including burn wounds or injuries from surgeries such as plastic surgery.

Green Synthesis of CuO Nanoparticles Using Agaricus bisporus Extract as a Highly Efficient Catalyst for the Suzuki Cross-Coupling Reaction.

Copper oxide nanoparticles (CuONPs) were synthesized using a rapid, eco-friendly, cost-effective, efficient, and biological method employing aqueous Agaricus bisporus extract as a capping and reducing agent. The formation of CuONPs was checked by UV-vis spectroscopy and was characterized by X-ray diffraction analysis (XRD), dynamic light scattering spectroscopy (DLS), transmission electron microscopy (TEM), and surface area and porosimetry analyzer. The characterization results showed that the synthesized nanoparticles had a spherical-like appearance and a crystal structure with 40-100 nm particle size. The green synthesized CuONPs were found to be an excellent and sustainable heterogeneous catalyst (TOF up to 29700 h-1 ) for the Suzuki C-C coupling of aryl halides with phenylboronic acid in a very short reaction time (10 minutes). Moreover, the easily recovered catalyst can be reused five times with just a negligible reduction in catalytic behavior.

Rice husk coated with copper oxide nanoparticles for 17α-ethinylestradiol removal from an aqueous solution: adsorption mechanisms and kinetics.

The 17 α-ethinylestradiol (EE2) adsorption from aqueous solution was examined using a novel adsorbent made from rice husk powder coated with CuO nanoparticles (CRH). Advanced analyses of FTIR, XRD, SEM, and EDSwere used to identify the classification parameters of a CRH-like surface morphology, configuration, and functional groups. The rice husk was coated with CuO nanoparticles, allowing it to create large surface area materials with significantly improved textural qualities with regard to functional use and adsorption performance, according to a detailed characterization of the synthesized materials. The adsorption process was applied successfully with elimination effectiveness of 100% which can be kept up to 61.3%. The parameters of adsorption were affecting the adsorption process significantly. Thermodynamic data stated that the process of adsorption was endothermic, spontaneous, chemisorption and the molecules of EE2 show affinity with the CRH. It was discovered that the adsorption process controlled by a pseudo-second-order kinetic model demonstrates that the chemisorption process was controlling EE2 removal. The Sips model is regarded as optimal for representing this practice, exhibiting a significantly high determination coefficient of 0.948. This coefficient implies that the adsorption mechanism indicates the occurrence of both heterogeneous and homogeneous adsorption. According to the findings, biomass can serve as a cheap, operative sorbent to remove estrogen from liquified solutions.

Cell-Type-Dependent Dissolution of CuO Nanoparticles and Efflux of Cu Ions following Cellular Internalization.

CuO nanoparticles (NPs) show promising applications in biosensors, waste treatment, and energy materials, but the growing manufacture of CuO NPs also leads to the concerns for their potential environmental and health risks. However, the cellular fates of CuO NPs such as Cu ion dissolution, transformation, and efflux remain largely speculative. In the present study, we for the first time combined the gold-core labeling and Cu ion bioimaging technologies to reveal the intracellular fates of CuO NPs in different cells following cellular internalization of NPs. We demonstrated that the dissolution rate of CuO NPs depended on the cell type. Following CuO dissolution, limited transformation of Cu(II) to Cu(I) occurred within the cellular microenvironment. Instead, Cu(II) was rapidly eliminated from the cells, and such rapid efflux in different cells was highly dependent on the GSH-mediated pathway and lysosome exocytosis. The labile Cu(I) level in the two cancerous cell lines was immediately regulated upon Cu exposure, which explained their tolerance to Au@CuO NPs. Overall, our study demonstrated a very rapid turnover of Cu in the cells following CuO internalization, which subsequently determined the cellular toxicity of CuO. The results will have important implications for assessing the health risk of CuO NPs.

Laser induced plant leaf extract mediated synthesis of CuO nanoparticles and its photocatalytic activity.

Metal nanoparticles furnished by the green synthesis approach have exhibited fascinating attributes owing to their biocompatibility with biomolecules, and their rapid environmentally friendly synthesis. On copper oxide (CuO) nanoparticles, a laser induced bio reduction work has been accomplish using Centella asiatica aqueous extract at room temperature is the pioneer in the field. This synthesis technique is easy, fruitful, eco-friendly, and counterfeit for the size-tunable synthesis of diverse shapes of stable copper nanoparticles. UV-visible spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared Spectroscopy (FTIR), Energy - Dispersive X-ray Spectroscopy (EDX), X-ray diffraction (XRD) and photodegradation study have astounding properties of regulating the formation, crystalline nature, and morphology of an integrated specimen. Moreover, the obtained copper oxide nanoparticle has the tendency to decrease the absorbance maximum value of methylene blue because of the catalytic activity posed by these nanoparticles on the reduction of methylene blue by Centella asiatica. It has been studied and confirmed by UV-visible spectrophotometer, and it has been recognised as an electron relay effect.

Azadirachta indica-wrapped copper oxide nanoparticles as a novel functional material in cardiomyocyte cells: An ecotoxicity assessment on the embryonic development of Danio rerio.

This research reports on the production of copper oxide nanoparticles (CuO NPs) through the green synthesis method using Azadirachta indica (Ai) flower extract. Synthesized Ai-CuO NPs are characterized by Zeta Potential, TGA, SEM and TEM analysis. The Ai-CuO NPs gave a maximum peak at 270 nm. As per XRD studies, the Ai-CuO NPs obtained were crystalline. FTIR spectrum Ai-CuO NPs showed the presence of functional groups like the O-H group, aromatic group, etc. TEM and SEM assist in investigating the size and morphology of the Ai-CuO NPs, which were spherical and varied in size between 10.11 nm and 17.54 nm. EDAX showed that Ai-CuO NPs were pure with no impurities. The synthesized Ai-CuO NPs were then analyzed for their cytotoxicity at various concentrations (5, 10, 20, 30, 40 and 50 µg/mL) against H9c2 cardiomyocyte cells using MTT assay. DOX-induced H9c2 cell damage of apoptosis and ROS. The nanoparticle formed by Ai-CuO was cured with different concentrations (5, 10 and 20 µg/mL). In zebrafish, 48 hpf and 72 hpf were measured at 75 µM to reduce dysfunction and mortality during organ development. These results can have a beneficial impact on eco-toxicological effects.

Photocatalytic effect of CuO nanoparticles flower-like 3D nanostructures under visible light irradiation with the degradation of methylene blue (MB) dye for environmental application.

The present research work focuses on preparing 3D transition metal doped copper oxide nanostructures through sonication method and to investigate the effect of doping different transition metal into copper oxide (CuO) on the basic properties of CuO nanoparticles and, to study the photocatalytic behaviour of the doped CuO samples. The morphological studies performed with the help of SEM revealed the formation of flower like CuO 3D nanostructures for all the doped samples. The slight shift in the position of peaks in the x-ray diffraction (XRD) pattern confirms that doping has been successfully done into CuO. Also, the sharp diffraction peaks suggest the polycrystalline nature of the sample with monoclinic structure. The UV-vis absorption analysis reveals a bandgap of 2.26, 2.12 and 2.15 eV for the CuO samples doped with nickel, zinc, and iron respectively via Tauc plot. The photocatalytic performance of the samples tested through the degradation of methylene blue (MB) dye suggests that samples doped with Zn shows better degradation. Thus, it is evident that the morphology and the optical properties of the CuO can be tailored by doping transition metal into it.

An ultrasensitive sandwich-type electrochemical aptasensor using silver nanoparticle/titanium carbide nanocomposites for the determination of Staphylococcus aureus in milk.

A novel sandwich-type electrochemical aptasensor for the detection of Staphylococcus aureus (S. aureus) was developed. S. aureus aptamers were self-assembled onto the surface of a glassy carbon electrode (GCE) modified with nanocomposites comprising titanium carbide embedded with silver nanoparticles (AgNPs@Ti3C2) through hydrogen bonds and the chelation interaction between phosphate groups and Ti ions. In addition, the self-assembled aptamers were immobilized on CuO/graphene (GR) nanocomposites via π-π stacking interactions to serve as a signal probe. In the presence of the target S. aureus, the sandwich-type recognition system reacted on the surface of GCE, and the CuO/GR nanocomposites catalyzed the hydrogen peroxide + hydroquinone reaction producing a strong current response. Under the optimal experimental conditions, the current response of the aptasensor was linearly correlated with the concentration of S. aureus (52-5.2 × 107 CFU mL-1) with a low detection limit of 1 CFU mL-1. The aptasensor displayed good repeatability and excellent selectivity for S. aureus detection. Moreover, this aptasensor was applied to the detection of S. aureus in cow, sheep, and goat milk samples, affording recoveries ranging from 92.64 to 109.58%. This research provides a new platform for the detection of pathogenic bacteria and other toxic and harmful substances in food.

Experimental and Computational Studies on the Interaction of a Dansyl-Based Fluorescent Schiff Base Ligand with Cu2+ Ions and CuO NPs.

We studied the interaction of Cu2+ ions and CuO nanoparticles with the fluorescent Schiff base ligand H3L, which derives from the condensation of 4-formyl-3-hydroxybenzoic acid with N-(2-aminobenzyl)-5-(dimethylamino)naphthalene-1-sulfonamide (DsA). A detailed assignment of the most significant bands of the electronic and infrared spectra of H3L and DsA was performed using DFT methods, based on both crystal structures. The affinity of H3L to react with Cu2+ ions in solution (KB = 9.01 103 L mol-1) is similar to that found for the Cu2+ ions present on the surface of CuO NPs (KB = 9.84 103 L mol-1). Fluorescence spectroscopic measurements suggest five binding sites for H3L on the surface of the CuO NPs used. The µ-XRF analysis indicates that a polycrystalline sample of CuO-H3L NPs contains 15:1 Cu:S molar ratio (CuO:H3L). ATR-FTIR spectroscopy, supported by DFT calculations, showed that the HL2- (as a phenolate and sulfonamide anion) is coordinated to superficial Cu2+ ions of the CuO NPs through their azomethine, sulphonamide, and phenolic groups. A solution of H3L (126 ppb) shows sensitive responses to CuO NPs, with a limit of detection (LOD) of 330 ppb. The working range for detection of CuO NPs with [H3L] = 126 ppb was 1.1-9.5 ppm. Common metal ions in water, such as Na+, K+, Mg2+, Ca2+, Fe3+, and Al3+ species, do not interfere significantly with the detection of CuO NPs.

Synthesis, Characterization, and Antibacterial Activity of Mg-Doped CuO Nanoparticles.

This study aims to investigate the effect of magnesium (Mg) doping on the characteristics and antibacterial properties of copper oxide (CuO) nanoparticles (NPs). The Mg-doped CuO NPs were fabricated by the co-precipitation method. NPs were characterized by X-ray Powder Diffraction (XRD), Transmission Electron Microscope (TEM), Energy Dispersive X-ray (EDX) analysis, Fourier Transform Infrared Spectroscopy (FTIR), and Photoluminescence (PL). Broth microdilution, agar-well diffusion, and time-kill assays were employed to assess the antibacterial activity of the NPs. XRD revealed the monoclinic structure of CuO NPs and the successful incorporation of Mg dopant to the Cu1-xMgxO NPs. TEM revealed the spherical shape of the CuO NPs. Mg doping affected the morphology of NPs and decreased their agglomeration. EDX patterns confirmed the high purity of the undoped and Mg-doped CuO NPs. FTIR analysis revealed the shifts in the Cu-O bond induced by the Mg dopant. The position, width, and intensity of the PL bands were affected as a result of Mg doping, which is an indication of vacancies. Both undoped and doped CuO NPs exhibited significant antibacterial capacities. NPs inhibited the growth of Gram-positive and Gram-negative bacteria. These results highlight the potential use of Mg-doped CuO NPs as an antibacterial agent.

Synthesis of Copper Oxide-Based Nanoformulations of Etoricoxib and Montelukast and Their Evaluation through Analgesic, Anti-Inflammatory, Anti-Pyretic, and Acute Toxicity Activities.

Copper oxide nanoparticles (CuO NPs) were synthesized through the coprecipitation method and used as nanocarriers for etoricoxib (selective COX-2 inhibitor drug) and montelukast (leukotriene product inhibitor drug) in combination therapy. The CuO NPs, free drugs, and nanoformulations were investigated through UV/Vis spectroscopy, FTIR spectroscopy, XRD, SEM, and DLS. SEM imaging showed agglomerated nanorods of CuO NPs of about 87 nm size. The CE1, CE2, and CE6 nanoformulations were investigated through DLS, and their particle sizes were 271, 258, and 254 nm, respectively. The nanoformulations were evaluated through in vitro anti-inflammatory activity, in vivo anti-inflammatory activity, in vivo analgesic activity, in vivo anti-pyretic activity, and in vivo acute toxicity activity. In vivo activities were performed on albino mice. BSA denaturation was highly inhibited by CE1, CE2, and CE6 as compared to other nanoformulations in the in vitro anti-inflammatory activity. The in vivo bioactivities showed that low doses (5 mg/kg) of nanoformulations were more potent than high doses (10 and 20 mg/kg) of free drugs in the inhibition of pain, fever, and inflammation. Lastly, CE2 was more potent than that of other nanoformulations.

Responses of Prorocentrum cordatum (Ostenfeld) Dodge, 1975 (Dinoflagellata) to copper nanoparticles and copper ions effect.

In the present study, changes were determined in morphological, structural-functional, and fluorescent parameters of Prorocentrum cordatum with the addition of CuO nanoparticles (NPs) and copper ions (CuSO4). A stimulating effect of low Cu2+ concentrations (30 µg L-1) on algal growth characteristics was observed. Higher Cu2+ concentration of 60-600 µg L-1 and CuO NPs concentration of 100-520 µg L-1 inhibited algal growth. Ionic copper is more toxic to P. cordatum than NPs. After 72 h of algae cultivation in the medium supplemented with CuSO4 and CuO NPs, EC50 values (calculated based on cell abundance) were of 60 and 300 µg L-1 (in terms of copper ions), respectively. Reduction in algal growth rate is due to disruption in cell cycle, changes in nuclear morphology, chromatin dispersion, and DNA damage. The studied pollutants slightly affected the efficiency of P. cordatum photosynthetic apparatus. Addition of the pollutants resulted in an increased production of reactive oxygen species (ROS). At a concentration of Cu2+ of 120 µg L-1 and a concentration of CuO NPs 0-300 µg L-1 of CuO NPs increase in ROS production is short-term with a decrease at later stages of the experiment. This is probably due to the activation of antioxidant mechanisms in cells and an increase in the concentration of carotenoids (peridinin) in cells. The high values of ROS production persisted throughout the experiment at sublethal copper concentrations (400-600 µg L-1 of CuSO4 and 520 µg L-1 of CuO NPs). Sublethal concentrations of pollutants caused restructuring of cell membranes in P. cordatum. Shedding of cell membranes (ecdysis) and formation of immobile stages (temporary or resting cysts) were recorded. The pronounced mechanical impact of NPs on the cell surface was observed such as-deformation and damage of a cell wall, its "wrinkling" and shrinkage, and adsorption of NP aggregates.