modern research physics

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Dibenzo sulfoxide macrocyclic diamides possess a hydrophilic cavity surrounded by hydrophobic ring, which enable them to diffuse from cell membrane and interfere with different living systems including ion channels. This study evaluated cytotoxicity effects of this compound in a range of different doses on Balb/C mouse via inter peritoneal injection. Results showed that LD50 concentration was at 2500 µg/Kg.bodyweight. Histological evaluation of animals livers after one-week treatment to 1500 µg/Kg of this compound revealed insignificant changes in hepatocyte cords, portal area, sinusoids and cells of coopfer and hepatocytes with respect to control animals. On the other hand, Histological evaluation of animals’ testis indicated significant decrease in weight, seminiferous tubule diameter and volume of testis and also in the cell number of spermatogonia (A and B), primary spermatocytes, spermatides, spermatozoids and sertoli. In this condition of exposure, antioxidative enzyme activities of peripheral blood, liver and testis increased in a dose dependent manner and reached the highest and significant levels at 1500 µg/Kg. However, the increase in oxidative damage biomarkers including malondialdehyde (MDA) and dityrosine were considerable for peripheral blood and testis. Accordingly, the studied compound had toxic effect and could affected testis when the animals were treated with chemical agent subLD50 for one week. The liver didn’t show toxicity effect of this compound even at 1500 µg/Kg exposure for one week. It could be attributed to high metabolism potential and marked antioxidative activities of this tissue.

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The present work was an attempt to investigate the parameters which can affect the process of hydrogel formation in the presence of ultrasound. These parameters were concentration of the reactants (monomers and cross linker), the reaction medium (solvent, ionic strength, and pH), and acoustic parameters (power and pulse). The monomers were acrylic acid and acrylamide, and the cross linker was methylene bis acrylamide. The experiments were performed at a constant temperature of 37 °C. Pulsed power ultrasound was irradiated to the reaction mixture from the tip of a probe system. The results showthatultrasonic irradiation significantly reduces the reaction time and increases efficiency. Additionally, increasing glycerol in the solution changes the viscosity of the reaction for the better and increases the reaction rate. However, ionic strength and pH were not significantly effective in this respect. Results  showed  that ultrasonic acrylic  hydrogel  are sensitive to pH and temperature. Therefore, these  hydrogels is capable for rapid drug absorption and release according to porosity in their structure. These findings provide a better understanding of hydrogel synthesis and enable us to control the pertinent parameters.

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Department of Chemistry, Takestan Branch, Islamic Azad University, Takestan, Iran High frequency sound wave, ultrasound, is widely used to facilitate chemical reactions, especially in the polymerization reactions.This paper reports a study which synthesized acrylic hydrogel in the presence of ultrasonic irradiation (20-kHz, power 80%, pulse 8) in a water/glycerol medium. Acrylic acid (AA) and acrylamide (AAm) were used as acrylic monomers, and methylene bisacrylamide (MBA) as the crosslinker. The experiments were performed at a constant temperature of 37 °C. It was found that hydrogel formation is faster in the presence of ultrasound than in its absence. In addition, FT-IR, UV-Vis, and SEM spectroscopy showed that the hydrogel synthesized ultrasonically has a higher swelling capacity and a more uniform and porous structure. It was also discovered that hydrogel formation speeds up at higher quantities of glycerol. However, an increase in crosslinker concentration proved ineffective although it changed the appearance of the hydrogel. The method proposed in this research can be used in the synthesis of biomedical materials and in the development of drug delivery systems.