In-Utero Neurotoxicity of Nanoparticles

The unique physicochemical properties of nanoparticles (NPs) make them widely used in cosmetics, medicines, food additives, and antibacterial and antiviral compounds. NPs are also used in therapy and diagnostic applications. Depending on their origin, the NPs are commonly classified as naturally occurring and synthetic or anthropogenic NPs. Naturally occurring nanoparticles can be formed by many physical, chemical, and biological processes occurring in all spheres of the earth. However, synthetic NPs are specifically designed or unintentionally produced by different human activities. Owing to their nano size and special properties, the engineered NPs can enter the human body through different routes such as dermal penetration, intravenous injection and inhalation. NPs may accumulate in various tissues and organs including the brain. Indiscriminate use of NP is a matter concern due to the dangers of NP exposure to living organisms. It is possible for NPs to cross the placental barrier, and adversely affect the developing fetus, posing a health hazard in them by causing neurodevelopmental toxicity. Thus, NP-induced neurotoxicity is a topic that demands attention at the maternal-fetal interface. This chapter summarizes the routes by which NPs circumvent the blood-brain barrier, including recent investigations about NPs’ neurotoxicity as well as possible mechanisms involved in neural fetotoxicity.

Nano-Sized Effect on Liquid Phase and Their Energy

Regardless of the state of matter, such as solids, liquids, and gases, the smaller the matter size from bulk to nano-scale, especially in the quantum region, the more rapid is the energy increase. To this end, this study introduces the concept of a group system, in which atoms behave as one, and this system is reinterpreted as that comprising temperature–entropy (TS) energy in thermodynamic data. Based on this concept, water was passed through various mesh-like dissolved tubes, where the size and energy of the water group system were observed to change. Thereafter, as the scale and number of the meshes increased, the ozone, chlorine, and oxygen constituents, which are closely related to sterilization and washing, are generated, changing the basic water composition. Thus, this nano-size impact is not limited to solids and could facilitate in revolutionizing the future applications in fluids.

Numerical simulations for ferromagnetic resonance of nano-size island structures probed by radio-frequency scanning tunneling microscopy

We numerically calculated ferromagnetic resonance (FMR) spectra taken on a single-domain nano-size ferromagnetic island structure in the configuration of radio-frequency scanning tunneling microscopy (RF-STM), where RF electromagnetic waves are introduced into the tunneling gap through the probe tip. In this scheme, near-field in-plane azimuthal RF magnetic field induces FMR of an out-of-plane magnetized island situated below the tip under the external out-of-plane magnetic field. The amount of the magnetization of the island is effectively reduced by the resonance and the reduction can be detected from the spin-polarized tunneling conductance. From the calculated spectra we found that the FMR signal becomes larger with a smaller tip-sample distance and a sharper tip. It is also revealed that the azimuthal RF magnetic field and therefore the FMR signal are enhanced when a tip is located near the edge of the island.

Ovicidal, larvicidal and pupicidal efficacy of silver nanoparticles synthesized by Bacillus marisflavi against the chosen mosquito species

Microbial synthesis of silver nanoparticles is more advantageous and is eco-friendly to combat the various vectors that cause diseases in humans. Hence, in the present study a Bacillus strain is isolated from marine habitat and is evaluated for its ability to synthesize silver nanoparticles (AgNPs) and its efficacy evaluated against the immature stages of selected mosquito species. The effective candidate was confirmed to be Bacillus marisflavi after 16S rRNA sequencing. The synthesis of AgNPs was confirmed by UV-Vis spectrophotometer. Atomic Force Microscopic (AFM) analysis showed spherical nanoparticles. Size analysis using Scanning Electron Microscope (SEM) showed particles of nano size averaging 78.77 nm. The diameter of the particles analyzed by Dynamic Light Scattering (DLS) showed 101.6 nm with a poly-dispersive index of 0.3. Finally the elemental nature of the nanoparticles was identified by Fourier-transform infrared spectroscopy (FTIR). LC50 and LC90 values for the ovicidal, larvicidal and pupicidal efficacy of the AgNPs against the egg, larvae and pupae of Aedes aegypti, Culex quinquefasciatus and Anopheles stephensi respectively were evaluated. The present study revealed that the nanoparticles have an excellent toxic effect against the disease transmitting vector mosquitoes. Hence, the rapid synthesis of AgNPs would be an appropriate eco-friendly tool for biocontrol of vector mosquitoes.

Nano Pesticides Application in Agriculture and their Impact on Environment

Environmental contamination and the tolerance developed by the pests, pathogens are some of the environmental issues related to the aimless utilization of chemical pesticides. It has became matter of serious concern for environment, food quality and soil health. Nanotechnology, envisaged as a swiftly emerging field has capability to reform food systems in agriculture. Nanotechnology provides an imperishable solution to these problems by the establishment of nano-pesticides. The functional components or the conveyor molecules used are of nano size. The performance of these nano sized particles is much better the traditional pesticides, as the smaller size aids in proper spreading on the pest surface. Amelioration in solubility of operational components, betterment in stability of formulation, gradual liberation of operational components and enhancement in mobility are some of the paramount advantages of nano particles attributed to the minute size of particles and greater surface area. Thus, nano particles have strengthened activity against target pests in comparison to bulk materials. Furthermore, nano-formulations sustain productive use in agriculture by offering systemic properties, uniform leaf coverage and enhanced soil properties. Despite all the positive aspects, it might have certain negative effects as well, like exposure of humans through distinct routes Viz, exposure to nano pesticides either directly or indirectly like adsorption through skin, or inhalation while breathing air or transfer from one energy level to another by taking contaminated food and water.

Synthesis of ZIF-11- effect of source of zinc salts on the structure

In this paper, ZIF-11 material was synthesized from benzimidazole and different zinc salt sources at room temperature. The obtained samples were characterized using XRD, SEM, FTIR and TGA measurements. The results showed that the synthesized materials had nano-size, and uniformity with the sharp dodecahedrons structure of ZIF-11. Zinc sources had an influence on the size and nature of the ZIF-11 crystal. The average crystalline size of the nanoparticles calculated by Scherrer equation were 85.5 nm for sample of zinc nitrate, 91.9 nm for sample of zinc chloride and 111.5 nm for sample of zinc acetate. The obtained samples had high thermal stability ( 460 °C). The adsorption capacity of the synthesized materials for iodine from aqueous solution was very high (236 mg/g).

Synthesis of ZIF-67- Effect of solvent on the structure

In the present paper, ZIF-67 material was synthesized from cobalt (II) nitrate hexahydrate and 2-methyl imidazole in three different solvents (methanol, ethanol and acetone) at room temperature. The obtained samples were characterized using XRD, SEM, FTIR, TGA and nitrogen adsorption/desorption measurements. The results show that the synthesized ZIF-67 materials had a high purity, nano-size, and uniformity with the sharp dodecahedrons structure of ZIF-67. Solvents had an influence on the size and nature of the ZIF-67 crystal. The average crystalline size of the nanoparticles calculated by Scherrer equation were 64 nm for sample in acetone solvent, 128 nm for sample in ethanol solvent and 132 nm for sample in methanol solvent. The obtained samples had high thermal stability ( 320 °C). The ZIF-67 material with ethanol solvent had a high specific surface area (SBET) of 1506 m2/g. The synthesized samples exhibited better adsorption capacity of methyl oranges than that of rhodamine B.