The high impact of zinc chromium oxide nanocombs on development of larvicidal and antimicrobial performance.

Zinc chromium oxide (Cr/ZnO, 5wt.%) was prepared by a facile chemical co-precipitation route. The structure, composition, and chemical bonding were analyzed using X-ray diffraction (XRD), Energy dispersive X-ray spectroscopy (EDX), and Fourier-transform infrared spectroscopy (FTIR) indicating that chromium ions were integrated the host framework to form Cr/ZnO nanocomposite. Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) micrographs showed comb-shaped nanoparticles with an average size 20 nm and large surface area. The energy gap of the thin films was estimated from T% and R% measurements which exhibit a strong optical absorption edge close to the visible spectrum. The insecticidal activity of the synthesized nanocombs against C. pipiens larvae was evaluated with LC50 (30.15 ppm) and LC90 (100.22 ppm). Besides, the nanocomposite showed high antibacterial performance against gram-positive bacteria (Bacillus subtilis) and gram-negative bacteria (Proteus vulgaris) with inhibition zones 21.9 and 19 mm, respectively.

Integration of ZnO nanorods with silver ions by a facile co-precipitation for antimicrobial, larvicidal, and ovicidal activity.

BACKGROUND: Infectious diseases prompted by micro-organisms such as fungi, parasites, or microbes, have influenced many countries' public health causing death. Scientists declared that metal oxide composites have various advantages in the medical field such as the antimicrobial feature has freshly been revealed as well as its role in suppressing mosquito population. METHODS: In this work silver doped zinc oxide nanorods (Ag/ZnO NRs, 10 wt.%) were prepared by simple chemical route, and their microstructural characteristics were investigated by XRD, EDX, SEM, and TEM techniques. The antimicrobial, larvicidal, and ovicidal of the synthesized nanocomposites were examined. RESULTS: The synthesized nanocomposite exhibited binary phase of crystallite size 112 nm was calculated from Williamson-Hall method. EDX spectrum revealed the purity of the composite consists of Zn, O, and Ag elements. The SEM and TEM micrographs showed the particles in nanorods with high density on the surface. The energy gap [Formula: see text] was evaluated from the UV-Vis absorbance in the range from 2.90 [Formula: see text] 3.08 eV inside the visible spectrum. The antimicrobial activity of the nanorods was examined against Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) with inhibition zones 10.5 and 14.5 mm, respectively. Whereas gram-negative bacteria (Escherichia coli, Salmonella Typhimurium, and Pseudomonas aeruginosa) were 14 and 17 mm, respectively. Further, Candida albicans was investigated with inhibition zone 7.5 mm. Besides, the insecticidal impact of the nanocomposite against Culex pipiens larvae was performed at 30 mg/l causing 100% larval mortality with LC50 (11.78 mg/l). The micrograph images showed deformations in the larval body as well as egg resulting in zero egg hatchability. CONCLUSION: The findings approved that synthesized nanorods have a significant impact on controlling pathogens that impart different diseases to humans and the environment.

Modulation of the Morphological Architecture of Mn2O3 Nanoparticles to MnCoO Nanoflakes by Loading Co3+ Via a Co-Precipitation Approach for Mosquitocidal Development.

The spread of many infectious diseases by vectors is a globally severe issue. Climate change and the increase of vector resistance are the primary sources of rising mosquito populations. Therefore, advanced approaches are needed to prevent the dispersal of life-threatening diseases. Herein, Mn2O3 NPs and MnCoO nanocomposites were presented as mosquitocidal agents. The synthesized samples were prepared by a co-precipitation route and characterized using different techniques indicating the change of host Mn2O3 structure to 2D MnCoO nanoflakes with Co3+ integration. The thermal decomposition of the nanoparticles was examined by TGA analysis, showing high stability. The energy gap (Eg) of Mn2O3 was estimated within the visible spectrum of the value 2.95 eV, which reduced to 2.80 eV with doping support. The impact of Mn2O3 and MnCoO on immature stages was investigated by semithin photomicrographs exhibiting significant changes in the midgut, fat tissue and muscles of the third larval instar. Moreover, the external deformations in pupae were examined using scanning electron microscopy (SEM).

Ultrastructural changes in the fat body of desert locust, Schistocerca gregaria (Orthoptera: Acrididae) treated with zinc chromium oxide nanostructures via chemical co-precipitation approach.

The present work aims to investigate the ultrastructural changes in the fat body of fifth instar nymphs Schistocerca gregaria (Orthoptera: Acrididae) treated with zinc chromium oxide (ZnCrO). The nanoparticles (NPs) were prepared by co-precipitation route and characterized using X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The ZnCrO NPs exhibited polycrystalline hexagonal structure, composed of spherical-hexagonal shapes with an average size ~ 25 nm. Besides, the UV-Vis spectrophotometer (Jasco-V-570) was utilized for optical measurements. The energy gap [Formula: see text] was estimated from the transmittance (T%) and reflectance (R%) spectra through the range of 3.307-3.840 eV. In biological sections, S. gregaria 5th instar nymphs, TEM images demonstrated that the fat body was strongly impacted with the concentration 2 mg NPs result in great agglomeration of chromatin in the nucleus as well as haemoglobin cells (HGCs) pierced with malformed trachea (Tr) at 5th and 7th days post treatment. The obtained results indicated a positive action of the prepared nanomaterial on Schistocerca gregaria fat body organelles.

Synthesis of MnCoO/CNT nanoflakes for the photocatalytic degradation of methyl orange dye and the evaluation of their activity against Culex pipiens larvae in the purification of fresh water.

Researchers worldwide have been looking forward to using novel ways to purify fresh water containing pollutants and disease vectors. In the current work, nanoparticles were introduced as a promising technique for cleaning water and saving human health and living organisms. The nanocomposites, MnCoO and MnCoO/CNTs, were fabricated by a cost-effective co-precipitation method. Phase and molecular structures were investigated by XRD and Raman spectroscopy. The samples exhibited polycrystalline nature of binary phase and weak crystallinity. The elemental composition was recorded by EDX spectra, revealing the purity of the nanoparticles. The surface morphology and particle distribution were described using SEM and TEM micrographs, indicating that MnCoO/CNTs are nanoflakes with a large surface area. The optical parameters include α, E g, n, k, which were identified from T% and R% measurements, suggesting that MnCoO has a direct band gap that reduced with the CNT support. The photocatalytic activity of MnCoO/CNTs was examined for the degradation of methyl orange dye with an efficiency of ∼90.97% over 0.6 g L-1 within 50 min under UV irradiation. In the larvicidal activity, the micrograph images revealed the impact of the nanoflake particles on the 4th instar larvae, where the enzymatic activity of esterases acetylcholinesterase, α- and ß-carboxylesterase, and transaminases drastically decreased with the MnCoO/CNT ratio.

Comparative Study of Larvicidal Activity of Spinel Co3O4 Nanorods and Entomopathogenic Metarhizium brunneum Conidia against Culex pipiens.

Herein, we report the synthesis of spinel cobalt oxide nanorods (Co3O4 NRs) by a modified co-precipitation approach and examine their larvicidal activity against Culex pipiens. The structure and morphology of the as-prepared Co3O4 NRs were emphasized using X-ray diffraction (XRD), Raman spectroscopy, energy dispersive X-ray spectroscopy (EDAX), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). It was found that Co3O4 nanostructures have a face-centered spinel cubic crystal structure with a mean crystallite size of 38 nm. These nanostructures have a rod like shape with a mean diameter of 30 nm and an average length of 60 nm. The TGA measurements revealed the high stability of the formed spinel cubic structure at 400 °C. The optical behavior indicates the direct transition of electrons through an optical band gap in the range of 2.92-3.08 eV. These unique chemical and physical properties of Co3O4 NRs enabled them to be employed as a strong agent for killing the C. pipiens. A comparison study was employed between the as-prepared Co3O4 and the entomopathogenic fungus Metarhizium brunneum as a control agent of C. pipiens larvae. The results revealed that the as-prepared nanorods have higher mortality against C. pipiens larvae compared with the well-known M. brunneum.

The fabrication of an innovative extremely sensitive nano green carbon paste electrode amended with the nanocomposite CuO/Y for electrochemical quantification of amprolium in sheep meat and liver samples.

In this work, carbon paste electrode (CPE) and modified CPE with copper oxide or copper yttrium oxide were prepared for determining amprolium hydrochloride (AMP) by differential pulse voltammetry. AMP has an antiprotozoal activity for treating coccidiosis in poultry; their retaining- in sheep meat and livers- induces adversative effects for the customer. XRD pattern was employed to define the fabricated nanostructured materials; the elemental composition of the nanocomposite was examined using EDX spectra. Over a pH ranging from 2 to 8, the oxidation process of AMP was studied using phosphate buffer. The scan rates were studied over a wide range (20 to 140 mV s-1) using cyclic voltammetry. The developed sensor shows a wide linear range (1.0 × 10-8-1.0 × 10-3 M) with a detection limit of 2.32 × 10-9 M. This method can quantify AMP in pharmaceutical form, sheep meat, and liver samples.