CuO Nanoparticles Research Articles

Efficacy of zinc and copper oxide nanoparticles as heat and corrosion-resistant pigments in paint formulations

This study focuses on the synthesis of zinc and copper oxide nanoparticles using green methods by plant extracts. The resulting metal oxides were analyzed using FT-IR spectroscopy, TGA, TEM, zeta potential and assessed for their efficacy as pigments based on properties such as Hydrogen Ion Concentration, Oil absorption, Moisture Content, Fineness of grinding, Bleeding, and loss on ignition. The results confirmed that the prepared ZnO and CuO nanoparticles exhibited the formation of nanoparticles in the range of 10–40 nm with potential as pigments. Two paint formulations incorporating these nanoparticles and silicon resins as binders were tested for physico-mechanical attributes, chemical resistance, heat resistance, and corrosion resistance of the dry paint films. The study found that the films containing the prepared oxides demonstrated excellent performance, with no damage or color alteration observed after exposure to temperatures up to 500 °C. Moreover, the paint films containing ZnO nanoparticles showed superior efficiency after a 500 h salt spray test compared to those with CuO nanoparticles. These findings suggest that the synthesized mixed oxide nanoparticles are promising candidates for heat-resistant pigment applications.

Thermal hysteresis enhancement and dispersion thermal stability in paraffin actuators: Comparison of pan-nanofibers vs metal oxide nanoparticles use

In this research, the possibility of thermal property enhancement of paraffin actuators with nanofiber and metal oxide nanoparticle addition was experimentally evaluated. Besides pure paraffin compound, paraffin mixed with the CuO, Fe3O4, ZnO, Al2O3, and electrospun polyacrylonitrile (PAN) nanofiber nanoparticles were used, and a significant hysteresis improvement at first-level measurement was observed as 24.6, 26.2, 20.0, 29.2, and 30.8 % sequentially for the samples respectively compared with pure paraffin. Thermal dispersion stability of the nanocomposites was comprehended via computer tomographic (CT) investigation. The excessive precipitation of CuO, Fe3O4, and ZnO particles in the paraffin nanocomposite was observed. Precipitation of PAN Nanofiber- and Al2O3-Paraffin nanocomposite was not visually detectable via CT throughputs. The effect of thermal dispersion stability on the hysteresis performance of the nanocomposites was also investigated to ensure long-term consistent hysteresis performance advantages in paraffin actuators. Thermal dispersion stability effect on hysteresis performance of paraffin actuators with CuO, Fe3O4, ZnO, Al2O3, and PAN nanofiber nanocomposite paraffin compounds showed losses as 14.3, 14.6, 5.8, 4.3 and 2.2 % sequentially for the samples respectively.

Using Femtosecond Laser Light to Investigate the Concentration- and Size-Dependent Nonlinear Optical Properties of Laser-Ablated CuO Quantum Dots.

In this work, the nonlinear optical (NLO) properties of CuO nanoparticles (CuO NPs) were studied experimentally using the pulsed laser ablation (PLA) technique. A nanosecond Nd: YAG laser was employed as the ablation excitation source to create CuO NPs in distilled water. Various CuO NPs samples were prepared at ablation periods of 20, 30, and 40 min. Utilizing HR-TEM, the structure of the synthesized CuO NPs samples was verified. In addition, a UV-VIS spectrophotometer was used to investigate the linear features of the samples. The Z-scan technique was utilized to explore the NLO properties of CuO NPs samples, including the nonlinear absorption coefficient (β) and nonlinear refractive index (n2). An experimental study on the NLO features was conducted at a variety of excitation wavelengths (750-850 nm), average excitation powers (0.8-1.2 W), and CuO NPs sample concentrations and sizes. The reverse saturable absorption (RSA) behavior of all CuO NPs samples differed with the excitation wavelength and average excitation power. In addition, the CuO NPs samples demonstrated excellent optical limiters at various excitation wavelengths, with limitations dependent on the size and concentration of CuO NPs.

Effect of ionic liquid on dispersion stability and antiwear behavior of CuO nanoparticles added to polyalphaolefin base oil

The experimental study assessed the impact of choline chloride cation-based ionic liquid (IL), on the dispersion stability and wear characteristics of copper (II) oxide (CuO) nanoparticles (NPs) in synthetic base oil (PAO 10). CuO NPs, averaging 50 nm in size, underwent surface modification using varying concentrations of the IL (0.25%, 0.5%, 0.75%, and 1% by weight). The formulations were subjected to sliding wear tests to evaluate their wear behavior. Analysis of the worn surfaces utilized scanning electron microscopy, energy-dispersive x-ray spectroscopy, and atomic force microscopy. The results indicated that the combination of 0.75% IL and 1% CuO NPs provided optimal dispersion and exhibited effective surface mending, enhancing wear protection by 21.1% than that of PAO 10. The formulation containing 1% IL and 1% CuO NPs demonstrated the highest load carrying capacity among all tested compositions. In terms of wear behavior, the nanolubricant formulations with 0.75% and 1% IL outperformed the lubricant formulation containing 1 wt% of the commercial antiwear additive Zinc dialkyldithiophosphates (ZDDP).

Enhancement of turbulent heat transfer by using CuO nano-particle and twisted tape

AbstractA computational model is developed to investigate the convective heat transfer properties and the fluid flow characteristics of cupric oxide - water nano-fluid in a horizontal circular pipe aiming to provide insights into optimizing heat transfer in such systems. A twisted tape with varied twist ratios is inserted. This quantitative investigation used five Reynolds number from 4,000 to 12,000 under a uniform heat flux scenario of 25,000 W m−2. All experiments were performed as a single-phase fluid with cupric oxide values of 0, 0.4, 1, and 2% by volume. By reducing the twist ratio and increasing volume concentration, the average heat transfer coefficient of cupric oxide-water nano-fluid was improved. For a twist ratio of 4D, the maximum heat transfer improvement was 228% greater than the plain pipe. The presence of twisted tape with modest step ratios causes the friction factor to grow.

Core/Shell-Like Magnetic Structure and Optical Properties in CuO Nanoparticles Synthesized by Green Route

Core/Shell-Like Magnetic Structure and Optical Properties in CuO Nanoparticles Synthesized by Green Route

Biofabrication of highly effective and easily regenerated CuO nanoparticles as adsorbents for Congo red and malachite green removal

An effective and easily regenerated adsorbent is the one for which scientists are making an effort to explore. In this study, copper oxide nanoparticles (CuO NPs) were synthesized in a green manner from a leaf extract of Moringa stenopetala and used for dye adsorption. XRD, FTIR, and SEM were employed for the characterization of CuO NPs. The crystallite size of the CuO NPs was calculated via Debye–Scherrer equation from the XRD data and was found to be 8.33 nm. The Cu–O bonding bending vibration at 1116 cm− 1 and stretching vibration at 1649 cm− 1 observed from the FTIR data strongly confirmed the formation of CuO NPs. SEM morphology analysis confirmed the formation of nanoparticles with a plate-like morphology and a spherically random orientation. The zero-point charge of CuO NPs was investigated and reported to be at pH 7. The adsorption of dyes on the greenly produced CuO NPs was studied by optimizing different adsorption parameters. The removal efficiencies of the green CuO NPs adsorbent were 99.54% at the optimum conditions (pH, 4; dye concentration, 30 mg/L; amount of adsorbent, 0.25 g; and contact time, 80 min) and 98.33% at the optimum conditions (pH, 11; dye concentration, 20 mg/L; amount of adsorbent, 0.4 g; and contact time, 80 min) for congo red and malachite green, respectively. The adsorption efficiency of the biosynthesized CuO NPs for the mixture of the two dyes was 92.3%. The green synthesized adsorbent was regenerated and able to work effectively for four cycles for the two dyes. The results of the kinetics-type investigation indicate that the adsorption of both dyes by the CuO NPs adsorbent best fits a pseudo-second-order model. The isotherm model-type investigation resulted in the fitting of the Langmuir adsorption isotherm for both the congo red and malachite green dyes.

Synergy of photoluminescence emission and antibacterial activity of Ag-Cu2O nanocomposite

Conglomerate nanocomposites comprising metal and metal oxide hold significant potential for exhibiting properties that surpass the combined characteristics of their individual components, owing to the interactions occurring at the interfaces between the metal and metal oxide elements. In this study, we present the synthesis of Cu2O nanoparticles (NPs) (with diameters ranging from 40 to 53 nm) and Ag-Cu2O nanocomposites using an aqueous solution method at room temperature, employing varying concentrations of Ag NPs. Through optical absorption studies, we determined the optical band gap of Cu2O NPs in 0.5Ag-Cu2O, 1Ag-Cu2O, and 1.5Ag-Cu2O nanocomposites samples to be 2.13 eV, 2.25 eV, 2.34 eV, and 2.41 eV, respectively. The x-ray diffraction data are analysed using the Williamson–Hall technique and revealed noteworthy variations in microstructural characteristics such as strain and stress within the Cu2O nanocrystallites fabricated under different Ag concentrations. The nanocomposites amplified the intensities of violet-blue, blue, and green photoluminescence (PL) emissions, attributable to the interfaces between Ag and Cu2O, lattice mismatches, and the induced microstructural parameters lattice strain, and stress of Cu2O nanocrystallites. The enhanced PL intensities can be attributed to the influence of the local electric field on the Ag core composites. The Ag-Cu2O nanostructure exhibits potential applications in water purification technologies, while the PL emission properties and low band gap (∼2.13 eV) hold promising applications in optoelectronic devices. The antibacterial activities of Cu2O and Ag-Cu2O nanomaterials against Enterococcus faecalis and Escherichia fergusonii are examined using MH agar well plate diffusion methods. Here, Ag NPs enhance bactericidal effectiveness through enhanced interaction with bacteria and the release of Ag+ ions, while the Cu2O shell discontinuity on Ag NPs contributes to their unique antibacterial properties.

Boosting selectivity for multi-carbon products in electrochemical CO2 reduction via enhanced hydroxide adsorption in ultrafine CuOx/CeOx nanoparticles

The electricity-driven reduction of CO2 presents a unique prospect of mitigating atmospheric CO2 levels and converting renewable energy into chemical fuels. However, the lack of an efficient catalyst that can transform CO2 into desired products with appreciable selectivity at commercially relevant current densities (ID) impedes the practical implications of this technology. This work describes a scalable approach for producing ultrafine nanoparticles of CuOx-CeOx (CuCe) composites via rapid coprecipitation under oxygen-deprived conditions. In this process, Ce(OH)3 acts as a reducing agent converting Cu(OH)2 into ultrafine Cu2O nanoparticles. Thus, the Ce: Cu ratio in composite effectively controls the particle size and bulk structural fixture of the CuCe composites. Despite having lower ECSA, The CuCe composites exhibit superior catalytic performance compared to CuO, with significantly higher selectivity for ethanol production and lower selectivity for CO and H2. The Cu1.5Ce prepared using a Cu: Ce ratio of 1.5:1, demonstrated remarkable catalytic activity with Faradaic efficiencies (F. E.) of 34.2 % for ethanol, 44.1 % for ethylene, and 81.08 % for multi-carbon (C2+) products. Moreover, while operating at the ID of 500 mA cm−2, Cu1.5Ce achieves a single pass CO2 conversion (SPCC) of 19.9 %, and a half-cell energy efficiency (E. E. half-cell) of 31.5 % for the C2+ products. It produces the C2+ products at the partial current density (pID) of 405.4 mA cm−2. The superior performance of Cu1.5Ce can be attributed to the improved hydroxide adsorption and partial retention of oxidized copper species under cathodic bias.

Dual-mode fluorescent and colorimetric sensing of thiourea and aluminum ion in natural water based on CuO nanoparticles.

CuO nanoparticles with good water solubility and uniform particle size were successfully prepared. Interestingly, the oxidase-like activity of CuO NPs was continuously enhanced by the addition of thiourea (TU), and the enzyme activity was further enhanced by the addition of aluminum ion (Al3+). By systematically exploring and optimizing the experimental conditions, including the key parameters such as temperature, reaction time, and pH, a fluorescence-colorimetric dual-mode sensing system based on CuO nanoparticles was constructed. The detection range of TU and Al3+ were 1-100 µM and 1-100 µM, respectively, and the selectivity and precision of detection were further improved. In addition, the catalytic mechanism of CuO NPs as oxidase-like catalysts and the specific process in the reaction were investigated. Finally, the nano-sensing system was successfully applied to the analysis of three real environmental samples, namely, tap water, lake water and river water, which provided an effective new strategy for the future development of nano-sensing technology for TU and Al3+.

Unveiling the Potential of CuO and Cu2O Nanoparticles against Novel Copper-Resistant Pseudomonas Strains: An In-Depth Comparison.

Four novel Pseudomonas strains with record resistance to copper (Cu2+) previously isolated from ecologically diverse samples (P. lactis UKR1, P. panacis UKR2, P. veronii UKR3, and P. veronii UKR4) were tested against sonochemically synthesised copper-oxide (I) (Cu2O) and copper-oxide (II) (CuO) nanoparticles (NPs). Nanomaterials characterisation by X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and High-Resolution Transmission Electron Microscopy (HRTEM) confirmed the synthesis of CuO and Cu2O NPs. CuO NPs exhibited better performance in inhibiting bacterial growth due to their heightened capacity to induce oxidative stress. The greater stability and geometrical shape of CuO NPs were disclosed as important features associated with bacterial cell toxicity. SEM and TEM images confirmed that both NPs caused membrane disruption, altered cell morphology, and pronounced membrane vesiculation, a distinctive feature of bacteria dealing with stressor factors. Finally, Cu2O and CuO NPs effectively decreased the biofilm-forming ability of the Cu2+-resistant UKR strains as well as degraded pre-established biofilm, matching NPs' antimicrobial performance. Despite the similarities in the mechanisms of action revealed by both NPs, distinctive behaviours were also detected for the different species of wild-type Pseudomonas analysed. In summary, these findings underscore the efficacy of nanotechnology-driven strategies for combating metal tolerance in bacteria.

The Effects of Adding TiO2 and CuO Nanoparticles to Fuel on Engine and Hand–Arm Driver Vibrations

Occupant comfort is a key consideration in automobile dynamics, with vibrations potentially causing long-term physical discomfort, especially for drivers. This study investigates the impact of adding TiO2 and CuO nanoparticles to fuel on engine-induced vibrations. Experiments were conducted at various nanoparticle concentrations (0, 50, 100, and 150 ppm) and engine speeds (1000, 2000, and 3000 rpm). Key performance metrics, including kinematic viscosity, density, heating value, thermal conductivity, and brake power (BP), were analyzed. The results indicated that increasing nanoparticle concentration led to a rise in BP. The highest reduction in root mean square (RMS) vibration accelerations occurred at 3000 rpm and 150 ppm, with vibration reductions of 30.33% for CuO and 28.61% for TiO2. Additionally, 8–10% of engine vibrations were transmitted to the steering wheel. The use of 150 ppm CuO nanoparticles resulted in reduced vibration transmission to the steering wheel at all tested speeds. These findings suggest that nanoparticle-enhanced fuels can significantly reduce engine vibrations, potentially improving driver comfort and reducing wear on vehicle components.

Enhanced-electrochemiluminescence biosensor for detecting miRNA-21 based on a CuO-mediated click reaction and catalytic hairpin self-assembly

MicroRNAs (miRNAs) are closely associated with cancer and have been considered cancer biomarkers. Herein, we propose an electrochemiluminescence (ECL) biosensor for detecting miRNA-21 based on target-induced catalytic hairpin self-assembly (CHA) and CuO-mediated azide–alkyne cycloaddition. Two hairpin DNAs were employed: one was immobilized on magnetic beads (HP2) and another was labeled with CuO (HP1–CuO). HP1 and HP2 formed a duplex through CHA induced by miRNA-21, resulting in the immobilization of CuO on magnetic beads and in the recycling of miRNA-21. After magnetic separation, CuO was treated with hydrochloric acid to release Cu2+, which concentration is quantitatively proportional to the target concentration. Subsequently, Cu2+ was reduced to Cu+, which catalyzed the click reaction between Fc–C CH and SH-DNA-N3+ immobilized on a Au/g-C3N4 modified electrode. Thus, the ECL of Au/g-C3N4 was quenched by Fc, and miRNA-21 was indirectly detected through a change in ECL intensity. Benefiting from the amplification effect of CuO nanoparticle loading, CHA-based target recycling, and the catalytic effect of click reaction, the proposed ECL biosensor showed high sensitivity. Experimental results indicate that the ECL biosensor proposed for detecting miRNA-21 exhibits a wide linear range from 1 fM to 1 nM and a low detection limit of 0.26 fM (3σ/S). Furthermore, the ECL sensor was capable of measuring miRNA-21 in real serum with high selectivity, indicating its notable applicable potential in biomedicine and clinical diagnosis.

Biosynthesis of CuO nanoparticle using leaf extracts of Ocimum lamiifolium Hochst. ex Benth and Withana somnifera (L) Dunal for antibacterial activity

Nanotechnology is becoming a promise for scientific advancement nowadays in areas like medicine, consumer products, energy, materials, and manufacturing. Copper oxide nanoparticles (CuO NPs) were synthesized using Ocimum lamiifolium Hochst. ex Benth and Withana somnifera (L) Dunal leaf extract via green synthetic pathway. The leaf of O. lamiifolium and W. somnifera were known to have strong antibiotic and antioxidant properties arising due to the presence of various secondary metabolites, including, flavonoids, alkaloids, saponins, tannins, cardiac glycosides, and phenolic compounds which serve as reducing, stabilizing, and capping agents for the CuO-Nanoparticles (NPs) synthesized. The biosynthesized CuO NPs were characterized based on Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy, and scanning electron microscopy. O. lamiifolium and W. somnifera leaf extract mediated synthesis could produce CuO NPs with average crystallite size of 15 nm and 19 nm, respectively. The biosynthesized CuO-NPs were further examined for antibacterial activity with Gram-positive (S. aureus) and Gram-negative bacteria (E. coli and P. aeruginosa). The GZDK-CuO NPs synthesized using W. somnifera leaf extract inhibited the growth of E. coli. and P. aeruginosa largely in comparison to S. aureus. Whereas the DMAZ-CuO NPs synthesized with the help of O. lamiifolium leaf extract showed higher bacterial inhibition on E. coli compared to S. aureus and P. aeruginosa. The minimum inhibitory concentration (MIC) values of both types of NPs are also assessed on all three pathogens. The newly biosynthesized nanoparticles, thus, were found to be optional materials for inhibiting the growth of drug- resistant bacterial pathogens.

Eco-friendly copper nanoparticles for acetamiprid pesticide mitigation in water effluents

Water pollution by pesticides is a significant environmental concern, given their extensive use in agriculture to meet food production demands. This study focuses on evaluating the effectiveness of biosynthesized copper nanoparticles in removing the pesticide acetamiprid (AMP). The degradation process is tracked by measuring the absorbance at 245 nm (AMP λmax) while considering variables such as adsorbent dosage, pH, and time. It provides valuable insights into the design and preparation of CuO nano adsorbents and their efficiency in purifying and remediating aquatic environments. The research investigated the ability of CuO nanoparticles, with an average size of 60 nm, to eliminate acetamiprid at very low concentrations (0.0005–0.01 mg/ml). The results showed that the nanoparticles could remove up to 97.5 % of AMP (0.01 mg/ml GT-CuO) after 90 min of contact time. Additionally, the study used the Langmuir isotherm model (R2 = 0.99125) and the pseudo-second order kinetic model (R2 = 0.98303) to model the adsorption of AMP on CuO NPs. Overall, CuO NPs derived from Glochidium tomentosum (GT) could offer a promising approach for adsorbing AMP pesticides.

The role of rice husk in Oreochromis niloticus safety enhancement by bio-adsorbing copper oxide nanoparticles following its green synthesis: an endeavor to advance environmental sustainability

Lowering nanoparticles (NPs) toxicity before discharge into aquatic environments and employing agricultural waste materials for environmental sustainability are necessary nowadays. Since this has never been done, this work examines how green CuO NPs treated with rice husk (RH) as a bio-adsorbent may be safer for Nile tilapia (Oreochromis niloticus) than chemically manufactured ones. So, five groups of fish were randomly placed in glass aquaria. One group was a control, and four groups received 50 mg/L green and chemically produced CuO NPs (GS and CS) with and without RH for 24, 48, and 96 h. RH was collected from all groups, and the results showed GS-CuO NPs had a greater adsorptive capacity than CS-CuO NPs after all time intervals. After analyzing fish indicators in all groups compared to the control, higher Cu bioaccumulation was exhibited in the liver and gills. The liver and gills showed elevated levels of glutathione peroxidase (GPx), catalase (CAT), and thiobarbituric acid reactive substances (TBARS), while the levels of glutathione reduced (GSH) were significantly lower. In addition, Cu exposure impaired liver and gill histology. Finally, our results indicated that using RH as an adsorbent for CuO NPs after their green synthesis instead of chemical synthesis before they enter the aquatic environment can enhance the overall health of fish and environmental sustainability.

In situ generation of cuprous oxide in metal-organic framework for significantly enhanced room-temperature ammonia sensing: Synergy enabling excellent sensitivity and selectivity

Development of effective strategies to improve the response sensitivity of metal-organic frameworks (MOFs) to target gases is imperative to further enhancing their application potential in gas sensing. In this work, series of CuHHTP/Cu2O (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) composites are successfully constructed by in-situ electrochemical reduction treatment of CuHHTP, and the changing trend of first increasing and then decreasing with increase of CuHHTP electrochemical reduction degree for their sensitivity to NH3 detection is revealed. When the average size of Cu2O nanoparticles generated in CuHHTP is 3.6 nm, the corresponding CuHHTP/Cu2O-A composite exhibits the best NH3 sensing performance compared to pristine CuHHTP, including significantly enhanced response sensitivity, ultralow experimental detection limit of 10 ppb, superior selectivity, good reproducibility, and excellent response stability even after placed for 90 days. More impressively, thanks to integration and synergy of the uniformly-dispersed small-sized Cu2O nanoparticles with significantly enhanced adsorption activity and capacity for NH3, the released large amount of uncoordinated hydroxyl groups that can interact with NH3, as well as the active sites of the CuHHTP substrate itself, the 10 ppb experimental detection limit for the CuHHTP/Cu2O-A-based sensors is not only the lowest one reported in the past 10 years for NH3 sensors based on copper-containing MOF and oxide materials, but also superior to that of 0.1–1 ppm for the existing commercial NH3 sensors. This work opens the avenue for design and development of novel MOF-based sensing materials.

Nanofiberous composite with CuO-Ag0 supported on bamboo/lycra for protection against transmittable infectious diseases

The transmittable infectious diseases, detrimental environmental contaminants and harmful UV radiations remained constant threat to human civilization. Cold, pneumonia, tuberculosis bacteria, rubella virus, RSV and COVID19, then urban and industrial emissions, volcanic eruptions, pollen, aerosols on one hand and skin cancer, sunburn, premature ageing and skin tanning on the other hand are some of the examples of serious risks to health, safety and well-being. The WHO reported over 7million worldwide deaths due to hazardous air contaminants. Exploiting the tremendous features of nanofiberous structure and excellent microbiocidal properties of Ag0 and CuO nanoparticles, a sustainable and stable nanofiber based composite Bmb-nanoNP was developed. Utilization of biocompatible, biodegradable, nontoxic and environmental friendly polymers enabled the composite as sustainable source for protective clothing purposes. The microparticulate filtration of Bmb-nanoNP was 99.13 % and 96 % with and without air suction respectively. The microbiocidal affect against E. coli and S. aureus strains was excellent(5.9 % and 8.86 % cell viabilities respectively). Similarly, the Bmb-nanoNP showed calculated UV protection factor (UPF) of 7954 (50 + rating).These characteristics demonstrated potential candidacy of the Bmb-nanoNP composite for multi-functional safety clothing applications.

Transformation of Engineered Copper Oxide Nanoparticles in Surface Waters.

Copper oxide nanoparticles (CuO-NPs) are widely used for their catalytic properties, conductive capacity, and innovations in the fields of superconductors, alloys, and solar energy sensors. To better understand the impact of water chemistry on the stability of CuO nanoparticles, a series of measurements were carried out on nanoparticles suspended in pure water, natural water, and water enriched with natural organic matter fulvic acid (FA). ICP-MS characterization in single-particle mode (SP-ICP-MS) was performed to determine the stability or transformation of nanoparticles in contrasting water conditions. We first observed that particle sedimentation was very fast in pure Milli-Q water. The addition of FA favored the dissolution of CuO-NPs with an increase in the dissolved copper concentration, for both Milli-Q water and natural water. The presence of FA also reduced the size of CuO-NPs (i.e., less aggregation) measured in natural water. By comparing signals of single particles, FA decreased nanoparticle numbers as well, confirming the increase in dissolution of CuO-NPs over time. The transformation products of CuO-NPs are important in the ecological context since the uptake and toxicity of parent nanoparticles differ from those of the chemical species in solution. Further considerations are needed on the fate of released NPs to better assess their exposure pathways to aquatic organisms and potential environmental risks.

CuO nanoparticles for glioma treatment in vitro and in vivo.

Glioma is the most prevalent malignant brain tumor in adults. The development of engineered nanomaterials (ENMs) has led to the emergence of innovative therapeutic strategies for gliomas. Therefore, our aim is to investigate the therapeutic effect of CuO nanoparticles (NPs) on glioma and provide data support for future research. The therapeutic effect of CuO NPs on glioma rats was explored through the detection of inflammatory factors, oxidase, pathological sections, immunofluorescence, neurotransmitter, glioma biomarker proteins and genes, and rat behavioral tests. Additionally, the application prospect of CuO NPs was evaluated by treating U87MG human glioma cell line. In this study, it was found that CuO NPs can alleviate the inflammatory reaction in the hippocampus tissue of glioma rats, promote the production of ·OH and lead to the up-regulation of catalase (CAT) and superoxide dismutase (SOD) enzyme activities. Treatment with CuO NPs also inhibited the expression of matrix metalloproteinase-9 (MMP-9) biomarkers in model rats and glioma cells. Moreover, it enhanced the release of neurotransmitters, which subsequently improved spatial recognition and memory ability of glioma rats. In conclusion, CuO NPs is a potential glioma treatment for ENMs, but still needs modification and modification strategies to improve its biocompatibility and targeted delivery.