Copper nanoparticles were synthesized by thermal decomposition using copper chloride, sodium oleate, and phenyl ether as solvent agents. The formation of nanoparticles was evidenced by the X‐ray diffraction and transmission electron microscopy. The peaks in the XRD pattern correspond to the standard values of the face centered cubic (fcc) structure of metallic copper and no peaks of other impurity crystalline phases were detected. TEM analysis showed spherical nanoparticles with sizes in the range of 4 to 18 nm. The antibacterial properties of copper nanoparticles were evaluated in vitro against strains of Staphylococcus aureus and Pseudomonas aeruginosa. The antibacterial activity of copper nanoparticles synthesized by thermal decomposition showed significant inhibitory effect against these highly multidrug‐resistant bacterial strains.
The use of nanoparticles (NPs) has generated an alternative pest control. The objective was to evaluate the insecticidal effect of zinc oxide nanoparticles (ZnO NPs), titanium dioxide nanoparticles (TiO2 NPs), and their combination on Bactericeracockerelli (Hemiptera: Triozidae) second-stage nymphs under laboratory and greenhouse conditions in tomato. The laboratory research was carried out with the leaf immersion bioassay method under a complete randomized design, and in the greenhouse by direct plant spraying under a randomized block design; in both designs, a control without NPs was added. Mortality was recorded every 24 h for 4 days. Both NPs in the laboratory and greenhouse showed toxicity to B. cockerelli nymphs. Results in the laboratory showed that NPs significantly caused increased mortality of 88, 99, and 100% 96 h after treatment of ZnO NPs, TiO2 NPs, and their combinations, at 1000, 100, and 250 ppm, respectively. Direct spray of plants in the greenhouse showed low mortality with 27, 32, and 23% after 96 h of ZnO NPs, TiO2 NPs, and their combinations, at 3000, 500, and 250 ppm, respectively. These results on B. cockerelli control seem promising. Nanoparticles as insecticides are a novel strategy, however, further investigation is required in field tests to obtain suitable efficacy for use in a pest management system.
Type 2 diabetes (T2D) in developed countries have a prevalence of 11% with diabetic foot infections as the most common cause of hospitalization and amputation. To achieve healing of the diabetic foot ulcer wounds, appropriate dressings are essential and their effectiveness can be enhanced with nanoparticles, nevertheless ideal combinations of dressing composition and nanodrugs require further testing in humans. We have developed a calcium alginate dressings with ZnO nanoparticles (CAZnODs) for the treatment of diabetic foot ulcers in human patients. To test the efficacy of CAZnODs we designed a randomized controlled clinical experiment on 26 T2D patients with foot ulcers. The patients were randomized into two groups: G1 treatment with calcium alginate with NPs (G1; n = 16), and group 2 received the treatment without NPs (G2, n = 10). The bandage change was performed every 48 h The duration of the protocol was established at 10 weeks. Here, we report healing was achieved in patients, with 75% wound closure in G1 under treatment with NPs of calcium alginate versus 71% in G2 (calcium alginate without NPs) (p = 0.011). The average healing time was 48 days in G1 and 72 days in G2. Our data shows that CAZnODs were well tolerated and did not interfere with the wound healing process. The final wound area and time of healing support the hypothesis that the use of calcium alginate dressings with nanoparticles may induce better tissue regeneration while avoiding T2D complications such as secondary infections.
Benefits of nanotechnology in agriculture include reduced fertilizer loss, improved seed germination rate and increased crops quality and yield. The objective of this research was to evaluate the effects of zinc oxide nanoparticles (ZnO-NPs), at 1500 ppm, on tomato (Solanum lycopersicum L.) growth. ZnO-NPs were synthetized to produce either spherical or hexagonal morphologies. In this research, we also studied two application methods (foliar and drench) and nanoparticles’ (NPs) surface modification with maltodextrin. The results obtained indicate that ZnO-NP-treated tomato plants significantly increased plant height, stem diameter and plant organs (leaves, stem and root) dry weight compared to plants without NP treatment.