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Inhalation Toxicity of Metal Particles and Vapors
Published in Jacob Loke, Pathophysiology and Treatment of Inhalation Injuries, 2020
In humans exposed occupationally, acute toxicity is primarily due to the irritative and allergenic properties of selenious acid (H2SeO3), formed from water and selenium dioxide. SeO2 is formed whenever selenium is heated in air. Symptoms are nonspecific, and include sneezing, coughing, dyspnea.
Nonisotopic Labeling
Published in Lelio G. Colombetti, Principles of Radiopharmacology, 2019
There is, unfortunately, no general method for direct introduction of 75Se, analogous to the Chloramine-T iodination procedure. Each 75Se-containing molecule is synthesized in a unique fashion, usually from 75Se selenium dioxide or selenous acid.
Radioactive Se And Te Labeled Imaging Agents
Published in Garimella V. S. Rayudu, Lelio G. Colombetti, Radiotracers for Medical Applications, 2019
The sodium borohydride reduction of Se-75 metal is suitable for microscale radiopharmaceutical preparations,6 however, Se-75 is available as selenious acid (H2SeO3) at a higher specific activity than Se-75 metal. It is also easier to handle the water soluble selenious acid than the selenium metal particles. The reduction of cold selenious acid directly to sodium hydrogen selenide by sodium borohydride has been reported.9 Using this improved synthetic procedure, a group of Se-75 labeled tertiary amines was prepared.10
Topical application of nanoparticles integrated supramolecular hydrogels for the potential treatment of seborrhoeic dermatitis
Published in Pharmaceutical Development and Technology, 2020
Abhinava Garg, Charan Singh, Deepak Pradhan, Goutam Ghosh, Goutam Rath
Selenium nanoparticles were prepared by chemical reduction technique using sodium borohydride as a reductant. Briefly, a solution of selenous acid (0.1 M) was prepared in a solvent mixture consisting of ethanol and water (1:2). A solution comprising of sodium citrate (0.6%w/v) and sodium lauryl sulphate (0.4%w/v) was prepared in another beaker, heated to 200 °C. Sodium citrate and sodium lauryl sulphate mixture were added dropwise to the above solution of selenous acid to make a final concentration of 0.05 M selenous acid. Sodium borohydride solution (0.4%w/v), was freshly prepared with deionized water and was added slowly to the above mixture with continuous mixing. Finally, a bright red color colloidal precipitates were formed. The resulted mixture was subjected to centrifuge at 12 000 rpm for 30 min. Pellets were collected and washed with ethanol to remove water. Developed selenium nanoparticles were quickly used to prepare hydrogel. Optimized selenium nanoparticles were characterized for antioxidant activity, particle size, and polydispersity index, surface morphology with field emission scanning electron microscope (FESEM), physical and thermal state using X-ray diffractometer and differential scanning calorimetry.
Design and synthesis of new spirooxindole candidates and their selenium nanoparticles as potential dual Topo I/II inhibitors, DNA intercalators, and apoptotic inducers
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2023
Samar El-Kalyoubi, Mohamed M. Khalifa, Mahmoud T. Abo-Elfadl, Ahmed A. El-Sayed, Ahmed Elkamhawy, Kyeong Lee, Ahmed A. Al-Karmalawy
In a conical flask, a solution of selenious acid (H2SeO3, 0.013 g, 0.01 mmol) in deionised water (80 mL) was prepared. The later solution was then heated and added to a DMSO (10 mL) solution of members 5b or 7d (0.01 mmol). The solutions were stirred continuously for 1 h at 60 °C. Ascorbic acid (200 µL, 40 mM) was introduced to the solutions as a catalyst. The ruby red SeNPs were then suspended. Different methods were used to confirm and characterise the formation of SeNPs as described in the following subsections.
Green synthesized selenium nanoparticles using Spermacoce hispida as carrier of s-allyl glutathione: to accomplish hepatoprotective and nephroprotective activity against acetaminophen toxicity
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2019
Vennila Krishnan, Chitra Loganathan, Palvannan Thayumanavan
Sh-SeNPs was prepared as described earlier [21]. Briefly, aqueous leaf extract of S. hispidia (Sh-ALE) was prepared by boiling 5 g of dried leaf powder in 100 ml of distilled water for 5 h. The aqueous extract was filtered and further used for SeNP synthesis. For Sh-SeNPs synthesis, 30 mM selenious acid solution was mixed with Sh-ALE at the ratio of 4:46, pH 9 and incubated at 40 °C for 1 h. The solution was centrifuged at 12,000×g for 10 min to obtain Sh-SeNPs. The Sh-SeNPs was washed five times to remove excess of the selenious acid.