Effect of Silicon Dioxide Nanoparticles on Liver Morphology of Rats in Parenteral Administration

The issue of the potential safety of silicon dioxide nanoparticles (SDNPs) remains relevant. In this connection, in order to use the unique capabilities of silicon nanostructures for biomedical purposes, as well as to level their toxic effects, a detailed study of these nanoparticles interaction with cells and tissues in vivo is required.The aim of the research is to reveal morphofunctional changes in a rat's liver after a single parenteral administration of 12 nm silicon dioxide nanoparticles for the period of six months.Material and methods. Using general histological and immunohistochemical methods to study the rats' liver after a single parenteral administration of 1 ml of silicon dioxide nanoparticles at a dose of 7 mg/kg of body weight at a concentration of 2 mg/ml. The sections of the rats' liver were studied by general histological and immunohistochemical methods after injection of 1mL of a SDNPs saline suspension at a concentration of 2 mg/mL (7mg/kg of body weight). Control animals were injected with 1 ml of saline solution. The material was collected in 21 days, 2, 4 and 6 months months after the administration of the SDNPs and it was fixed in 10% neutral formaldehyde.Results. The formation of granulomas in the liver on the 21st day of the experiment and an increase in the number of Kupfer cells were revealed. However, by the 2nd month of the experiment, the number of granulomas significantly decreases compared to the 21st day of the experiment and continues to decrease in subsequent periods. The average size of granulomas decreases during the 2nd month of the experiment and does not change during the subsequent periods of the experiment. After 6 months of the experiment, the morphofunctional state of the liver is characterized by slightly pronounced aseptic inflammation.Conclusion. A single parenteral administration of silicon dioxide nanoparticles causes pronounced aseptic inflammation of the liver, decreasing by the 6th month of the experiment. Connective tissue remodeling in the liver is not observed at all periods of the experiment.

Silicon Dioxide Nanoparticles Induce Innate Immune Responses and Activate Antioxidant Machinery in Wheat Against Rhizoctonia solani

The phytopathogenic basidiomycetous fungus, Rhizoctonia solani, has a wide range of host plants including members of the family Poaceae, causing damping-off and root rot diseases. In this study, we biosynthesized spherical-shaped silicon dioxide nanoparticles (SiO2 NPs; sized between 9.92 and 19.8 nm) using saffron extract and introduced them as a potential alternative therapeutic solution to protect wheat seedlings against R. solani. SiO2 NPs showed strong dose-dependent fungistatic activity on R. solani, and significantly reduced mycelial radial growth (up to 100% growth reduction), mycelium fresh and dry weight, and pre-, post-emergence damping-off, and root rot severities. Moreover, the impact of SiO2 NPs on the growth of wheat seedlings and their potential mechanism (s) for disease suppression was deciphered. SiO2 NPs application also improved the germination, vegetative growth, and vigor indexes of infected wheat seedlings which indicates no phytotoxicity on treated wheat seedlings. Moreover, SiO2 NPs enhanced the content of the photosynthetic pigments (chlorophylls and carotenoids), induced the accumulation of defense-related compounds (particularly salicylic acid), and alleviated the oxidative stress via stimulation of both enzymatic (POD, SOD, APX, CAT, and PPO) and non-enzymatic (phenolics and flavonoids) antioxidant defense machinery. Collectively, our findings demonstrated the potential therapeutic role of SiO2 NPs against R. solani infection via the simultaneous activation of a multilayered defense system to suppress the pathogen, neutralize the destructive effect of ROS, lipid peroxidation, and methylglyoxal, and maintain their homeostasis within R. solani-infected plants.

SONOLUMINESCENCE SPECTROSCOPY OF COLLOIDAL SUSPENSIONS: MOLECULAR, IONIC AND ATOMIC LUMINESCENCE DURING SONOCHEMICAL DECOMPOSITION OF SILICON DIOXIDE NANOPARTICLES CONTAINING RUTHENIUM AND COPPER COMPOUNDS

The article is devoted to an example of the sonoluminescence spectroscopy use, which was previously known as a method for analyzing substances from the characteristic spectra of their sonoluminescence only in true solutions, for carrying out a similar analysis of substances contained in insoluble nanoparticles in colloidal suspensions. The solutions sonolysis, that is, their irradiation with ultrasound, is accompanied by the formation of cavitation bubbles that vibrate radially at the frequency of the ultrasonic field. Volatile components of the solution enter the bubbles, evaporating from the liquid-gas interface; nonvolatile components can penetrate into the bubble as a result of the injection of solution nanodroplets into the gas phase, which occurs during intense bubble movements accompanied by their deformation. In a nonequilibrium plasma periodically forming in cavitation bubbles, destruction occurs, as well as collisional excitation of these components, followed by luminescence. It has been shown that this mechanism of sonoluminescence also operates in colloidal suspensions, where substances are present in the form of nanoparticles with sizes less than 50 nm. Such nanoparticles penetrate into moving cavitation bubbles, without destroying them, as part of nanodroplets, and then undergo decomposition in bubble plasma with the excited particles generation as emitters of characteristic sonoluminescence. In this work, we synthesized colloidal suspensions in dodecane of porous SiO2 nanoparticles containing adsorbed Ru(bpy)3Cl2 and CuSO4 salts. During moving single-bubble sonolysis for these suspensions, characteristic emission spectra of Ru and Cu atoms, SiO molecules, and Ru(bpy)3 ions suitable for sonoluminescence spectroscopic analysis were recorded. By comparing the experimental and calculated (at different temperatures) luminescence spectra of Ru atoms, we estimated the electron temperature attained upon acoustic compression of single bubble in colloidal suspension in dodecane: Te = 7000 K.

Enhanced X-ray Attenuating Efficiency of Silicon Dioxide Nanoparticles with Cesium Lead Bromide and 2,5-Diphenyloxazole Co-Embedded Therein

An X-ray-attenuation-based in vivo imaging can be a promising candidate for real-time detection of cancer in an early stage due to its significantly longer penetration depth compared to currently investigated fluorescence-emission-based imaging techniques. It has recently been demonstrated that this novel concept of imaging is feasible using cesium lead bromide (CPB) quantum dots (QDs) stably embedded in silicon dioxide (SiO2) nanoparticles (NPs). However, further improvements are necessary to realize its practical use, especially in terms of X-ray attenuation efficiency. In this study, we have found that the X-ray attenuation capability of CPB/SiO2 NPs was significantly enhanced by embedding an organic X-ray scintillator, 2,5-diphenyloxazole (PPO), together with CPB QDs in the NPs. The embedment not only solved the water dispersibility and stability problem of PPO, but also significantly increased the Hounsfield unit of the NPs, which was proportional to the degree of X-ray attenuation, by 2.7 times.

A pilot study on the effect of a novel feed additive containing exogenous enzymes, acidifiers, sodium butyrate and silicon dioxide nanoparticles on selected cellular immune indices and body weight gains of calves

Introduction The rearing of calves is a difficult period for farmers due to health problems to which the animals are prone this time. Since the use of antibiotics as growth promoters has been forbidden, various innovative feed additives have been tested in many countries around the world. Material and Methods In this study, experimental (E) calves were supplemented with a novel feed additive consisting of the pancreatic-like enzymes protease and lipase, a fat-coated mixture of organic fumaric, malic, citric and sorbic acids, sodium butyrate and silicon dioxide nanoparticles. Control (C) calves received feed without additive. During the supplementation, white blood cell (WBC) counts with leukocyte differentiation, percentages of B lymphocytes and T lymphocytes and their subpopulations, phagocytic activity and oxidative burst of circulating monocytes and granulocytes were examined. Body weight (b.w.) gains of the calves were also monitored. Results The WBC counts in the E and C calves were within the reference ranges throughout the study. In the analysis of the percentages of the lymphocyte subpopulations, phagocytic activity and oxidative burst, no statistically significant differences were reported between the E and C groups. However, higher average daily body weight gains were obtained for the E calves. Conclusion The study revealed that the examined feed additive did not modulate the immune response of the calves significantly. The tendency to higher daily average b.w. gains in the E calves than in the C calves suggests a beneficial effect of this feed additive.

Surface and optical properties of ethylene glycol-based nanofluids containing silicon dioxide nanoparticles: an experimental study

In this paper, the results of the experimental study on density, surface tension and optical properties of ethylene glycol-based nanofluids containing silicon dioxide have been presented. The nanofluid-air surface tension values were determined in the temperature range from 283.15 K to 318.15 K with Du Noüy ring method with the commercial equipment and self-made station. To determine the surface tension of a fluid, the information about its density is required; therefore, density of all examined nanofluids was measured in the same temperature range, and results were summarized in the paper. The refractive index of SiO$$_2$$ 2 -EG nanofluids was determined in the same temperature range in which the surface tension was examined. Finally, the extinction (UV–Vis spectra) of these materials was examined and presented.

Role of nanosilicab to boost the activities of metabolites in Triticum aestivum facing drought stress

Drought stress is a threat to agriculture which is decreasing the yield of crops and creating a considerable loss. This research focused on the part played by silicon dioxide nanoparticles (SiO2 NPs), biofertilizers, and nanosilicab on Triticum aestivum under control and drought stress. Nanosilicab enhanced the germination percentage, germination index, and germination vigor index by 23.07%, 14.49% and, 93.10% under control and 14.42%, 10.52%, and 46.15% under drought. In the pot experiment, the soil was treated with 150 mg/kg SiO2 NPs, 1% biofertilizer and, 1% nanosilicab before sowing. Nanosilicab increased shoot length and root length by 9.39%, 10.76%, 22.41%, 18.76%, 30.58%, and, 21.56% under control and drought stress conditions. It also increased photosynthetic pigments, osmolytes content, relative water content, membrane stability index, phenol, and flavonoid content. The increase in antioxidant activity was significantly high by the application of nanosilicab i.e. the augmentation in catalase, peroxidase, and superoxide dismutase was 68.65%, 83.69% and, 85.99% respectively. It also increased the indole acetic acid and cytokinin to 22.28% and 14.79% in comparison to control. The improvement in hundred grain weight and grains per spike by the use of nanosilicab was 36.25%, 38.76%, 27.47%, and 22.59% as compared to control. The positive interaction of nanosilicab with the roots of plants in the rhizosphere improved the growth of plants significantly and a potential candidate for application on crops. The novelty of this study lies in the formulation of nanosilicab and its role in drought amelioration.

Thin composite polymethyl methacrylate films with silicon dioxide nanoparticles

Techniques for the formation of thin polymer films based on polymethyl methacrylate and composite coatings with silicon dioxide nanoparticles on glass and silicon substrates have been optimised, and their structural characteristics have been studied by atomic force microscopy. The effect of the introduction of silicon dioxide nanoparticles and their content on the structure and wettability of the formed composite coatings is described. Experimental data are presented which prove that the incorporation of SiO2 nanoparticles into the structure of the polymethyl methacrylate polymer matrix leads to changes in the roughness parameters of the coatings.