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Pneumonitis induced by non-cytotoxic agents
Published in Philippe Camus, Edward C Rosenow, Drug-induced and Iatrogenic Respiratory Disease, 2010
Umair A Gauhar, J Allen D Cooper
Oral and parenteral gold salts (auranofin, gold sodium thiomalate, and gold aurothioglucose) have been used in the treatment of rheumatoid arthritis for over 50 years but are rarely used today because of the availability of safer and more effective therapeutic modalities. However, parenteral gold is a therapeutic option for patients refractory to other antirheumatic drugs. Gold salts are also used in selected cases of juvenile rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis and pemphigus.53,54 Gold may also be used in Felty’s syndrome (associated with anaemia and thrombocytopenia), since in such cases methotrexate may cause further bone marrow suppression.39 Gold salts exert an immunomodulatory effect through a decrease in neutrophil chemotaxis, decreased monocyte responsiveness and reduction in the release of proteolytic enzymes in the synovial fluid.53 They have also been shown to have a dose-dependent effect on cell proliferation by affecting thymidine incorporation and collagen synthesis.55
Seed Growth Method for the Synthesis of Metal Nanoparticles
Published in Cristobal N. Aguilar, Suresh C. Ameta, A. K. Haghi, Green Chemistry and Biodiversity, 2019
Lavanya Tandon, Divya Mandial, Rajpreet Kaur, Poonam Khullar
A typical procedure for the synthesis of AuNPs involves the following steps. First two steps involve reduction of gold salt using reducing agent such as sodium borohydride, ascorbic acid, citric acid, etc., while the second one involves stabilization of such metal nanoparticles by some suitable capping agents, such as trisodium citrate (Turkevich method), dihydrate or a surfactant, such as cetyltrimethylammonium bromide (CTAB), etc.21 In Turkevich method, it is the carboxy acetone obtained from oxidation of citrate that actually act as the stabilizing agent rather than the citrate itself. Due to the weak reducing strength of the citric acid, such reactions usually occur at a high temperature.
Gold Nanoparticles as Promising Agents for Cancer Therapy
Published in Hala Gali-Muhtasib, Racha Chouaib, Nanoparticle Drug Delivery Systems for Cancer Treatment, 2020
Nadine Karaki, Hassan Hajj Ali, Assem El Kak
This method is a robust strategy for preparation of monodisperse GNPs with a variety of well-controlled morphologies such as octahedron, polyhedron, sheet hexagon, nano-rods and icosahedron [53, 54]. The synthesis consists of reducing the gold salt by a polyol solvent in the presence of a suitable capping agent such as the polyvinylpyrrolidone (PVP), at a high temperature. The capping agent is an essential factor for stabilization of the formed nuclei (via adsorption on the metal surface) at the preliminary stage of reaction and for directing the morphology of the GNPs [55].
Preparation of Macroscopic Low-Density Gold Foams with Good Machinability
Published in Fusion Science and Technology, 2023
Sung Ho Kim, Swanee J. Shin, Suhas D. Bhandarkar, Theodore F. Baumann
Briefly, we measured changes in the weight of the PS-Au sample before and after baking, determined the ratios of and , and correlated these ratios with the thickness of the Au coatings under the assumption of the simple spherical geometry. As we increased the amount of gold salts from 80 to 250 mg, we observed an increase in the thickness of the gold coatings from 78 to 196 nm. We also determined the densities of these Au foams from the measurement of the weight, diameter, and height of the cylindrical samples. The measured foam densities fell within the reasonable range (70% to 93%) of the expected values from the assumption of the ideal fcc packing [Eqs. (1) through (5)]. By using different sizes of tubes in a plaster-of-Paris mold, we tuned the size of the resultant Au foams (4.8 to 11 mm in diameter) without a significant variation in the foam density.
Self-assembled molecular devices: a minireview
Published in Instrumentation Science & Technology, 2020
Stern et al.[6] proposed an improved DNA wire metallization method and its electrical characterization. The thickness of gold layer can be controlled by changing the concentration of gold salts from 100 to 1000 μm. By using high resolution scanning electron microscopy to observe the gold plate, conductors with different thickness can conduct nearly 80% of the total length of the wire with the highest thickness (27 ± 3 nm) as shown in Figure 1. The wires produced can be used for at least 18 months. This indicates that the thicker the gold plate, the fewer the defects, and the longer the conductive length. The metalized DNA wires fabricated by this method can achieve a long-distance conductivity from 400 to 700 nm, while wires of the same length have a long-distance conductivity of only 150 nm. These fabricated wires overcome the shortcomings of previous DNA metalized wires, such as irregularity and lack of end-to-end electrical connection, but there is still inhomogeneity of the metal coating.
Nano-dimensional gold synthesis for biomedical applications: upscaling and challenges
Published in Particulate Science and Technology, 2023
Subhasis Chakraborty, Suvadeep Mal, Asim Halder, Suvadra Das, Kalyan Kumar Sen, Arup Mukherjee, Partha Roy
Different types of microorganisms like bacteria, fungus, yeast is used to prepare inorganic nanoparticles like gold, silver, platinum etc. (Table 3). Interaction between metal nanoparticles and bacteria or yeast (Iravani 2011) is scientifically established to synthesize AuNPs (Willets and Van Duyne 2007). Gold salts are found to interact with bacteria cells and which convert gold to nano-dimension followed by purification and isolation (Patra et al. 2015) (Figure 5).