Application of copper(II)-based chemicals induces CH3Br and CH3Cl emissions from soil and seawater

Methyl bromide (CH3Br) and methyl chloride (CH3Cl) are major carriers of atmospheric bromine and chlorine, respectively, which can catalyze stratospheric ozone depletion. However, in our current understanding, there are missing sources associated with these two species. Here we investigate the effect of copper(II) on CH3Br and CH3Cl production from soil, seawater and model organic compounds: catechol (benzene-1,2-diol) and guaiacol (2-methoxyphenol). We show that copper sulfate (CuSO4) enhances CH3Br and CH3Cl production from soil and seawater, and it may be further amplified in conjunction with hydrogen peroxide (H2O2) or solar radiation. This represents an abiotic production pathway of CH3Br and CH3Cl perturbed by anthropogenic application of copper(II)-based chemicals. Hence, we suggest that the widespread application of copper(II) pesticides in agriculture and the discharge of anthropogenic copper(II) to the oceans may account for part of the missing sources of CH3Br and CH3Cl, and thereby contribute to stratospheric halogen load.

Effect of copper oxide nanoparticles on gene expression of NMDA receptor

Introduction. Copper plays an important role in the metabolism of the brain, but particles of copper, in the nanometer range, exhibit neurotoxic properties and cause malfunctioning of brain cells. Material and methods. For 6 weeks, 3 times a week, the animals were injected with a suspension of NPs of copper oxide. The determination of the expression of the genes GRIN1, GRIN2a, and GRIN2b, encoding the proteins GluN1, GluN2a, and GluN2b, respectively, was carried out by real-time PCR with probes. Results. A statistically significant decrease in the expression level of genes encoding NMDA receptor proteins was determined when exposed to 0.5 mg/ml CuO nanoparticles (ΔCt(GRIN1) = 0.813; ΔCt(GRIN2A) = 3.477; ΔCt(GRIN2B) = 1.37) in comparison with control group (ΔCt(GRIN1) = 6.301; ΔCt(GRIN2A) = 7.823; ΔCt(GRIN2B) = 4.747). Conclusion. Evaluation of gene expression of the NMDA receptor may be present in a genetic marker to determine the toxic effect of copper oxide nanoparticles; however, further studies are needed, including behavioral tests to confirm the clinical manifestations of neurodegenerative disorders.

Effect of Copper (II) Sulfate on the Properties of Urea Formaldehyde Adhesive

The purpose of this work is to investigate the effects of copper (II) sulfate on formaldehyde release and the mechanical properties of urea formaldehyde (UF) adhesive. Copper (II) sulfate has been used as a formaldehyde scavenger in UF resin, and its effects on the physical and chemical properties of UF adhesive have been studied. Moreover, the mechanical properties and formaldehyde release of plywood prepared with modified UF resin have been determined. The UF resin has been characterized by Fourier-transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA). FTIR spectra showed that the addition of copper (II) sulfate to the UF resin did not affect the infrared (IR) absorptions of its functional groups, implying that the structure of UF was not modified. Further results showed that: the free formaldehyde content of the UF resin by the incorporation of 3% copper (II) sulfate was 0.13 wt.%, around 71% lower than that of the control UF adhesive. With a copper (II) sulfate content of 3%, the formaldehyde release from treated plywood was 0.74 mg·L−1, around 50% lower than that from the control UF adhesive, and the bonding strength reached 1.73 MPa, around 43% higher than that of the control UF adhesive.

Effect of Copper and Titanium-Exchanged Montmorillonite Nanostructures on the Packaging Performance of Chitosan/Poly-Vinyl-Alcohol-Based Active Packaging Nanocomposite Films

In this study, CuMt and TiMt montmorillonites were produced via an ion-exchange process with Cu+ and Ti4+ ions. These nanostructured materials were characterized with X-ray diffraction (XRD) and fourier transform infrared spectroscopy (FTIR) measurements and added as nanoreinforcements and active agents in chitosan (CS)/poly-vinyl-alcohol (PVOH)-based packaging films. The developed films were characterized by XRD and FTIR measurements. The antimicrobial, tensile, and oxygen/water-barrier measurements for the evaluation of the packaging performance were carried out to the obtained CS/PVOH/CuMt and CS/PVOH/TiMt films. The results of this study indicated that CS/PVOH/CuMt film is a stronger intercalated nanocomposite structure compared to the CS/PVOH/TiMt film. This fact reflected higher tensile strength and water/oxygen-barrier properties. The antibacterial activity of these films was tested against four food pathogenic bacteria: Escherichia coli, Staphylococcus aureus, Salmonella enterica and Listeria monocytogenes. Results showed that in most cases, the antibacterial activity was generated by the CuMt and TiMt nanostructures. Thus, both CS/PVOH/CuMt and CS/PVOH/TiMt films are nanocomposite candidates with very good perspectives for future applications on food edible active packaging.

Protective role of silver nanoparticles in influenza infection

BACKGROUND: The present study assesses copper metabolism of the host organism as a target of antiviral strategy, basing on the virocell concept. This concept suggests that the targets for suppressing viral reproduction can be found in the hosts metabolism. AIM: Evaluation of the effect of copper status indicators on influenza infection in mice. MATERIALS AND METHODS: Silver nanoparticles (AgNPs) were used as a specific active agent because they reduce the level of holo-ceruloplasmin, the main extracellular cuproenzyme. The mouse model of influenza virus A infection was used with two doses: 1 LD50 and 10 LD50. The following treatment regimens were used: mice were pretreated four days before infection and then every day during infection development until the end of the experiment (day 14). RESULTS: The mice treated with AgNPs demonstrated significantly lower mortality, the protection index reached 6070% at the end of the experiment, and mean lifespan was prolonged. In addition, the treatment of the animals with AgNPs resulted in normalization of the weight dynamics. Despite the amelioration of the infection, AgNPs treatment did not influence influenza virus replication. CONCLUSIONS: This study provides support for the view that silver nanoparticles could be used as protection against influenza.