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Commentary
Published in Debasis Bagchi, Manashi Bagchi, Metal Toxicology Handbook, 2020
Debasis Bagchi, Manashi Bagchi
Now, let us discuss the noble metals Platinum, Gold, and Silver. The occurrence of platinum is extremely low in soil, water, and air. Platinum occurs naturally as the uncombined metal or as an alloy of platinum-iridium. South Africa is the major source of platinum, which provides 75% of the world’s total supply of platinum, while the USSR is the second-largest producer of platinum followed by North America.8 Platinum and/or its alloys are widely used in the chemical, electrical, glass, and aircraft industries, as well as for (a) making fine jewelry for its wear- and tarnish-resistance properties, which consumes almost 50% of the total produce, (b) manufacturing surgical tools, electrical resistance wires, laboratory utensils, and electrical contact points, (c) as a catalyst in the catalytic converter, (d) an integral constituent of the gasoline-fueled car exhaust system, (e) platinum is used for manufacturing of optical fibers and liquid crystal display glass, especially for laptops, and (f) platinum-derived cisplatin is extensively used as a chemotherapy medication for treating diverse cancers including breast, esophageal, testicular, ovarian, cervical, lung, bladder, mesothelioma and head and neck cancers, as well as brain tumors and neuroblastoma.8 However, platinum has been reported to aggravate the toxicity of selenium.8
High-temperature X-ray diffraction study of anorthite-tialite materials
Published in Canadian Metallurgical Quarterly, 2022
Vladimir Sokol'skii, Dmitry Pruttskov, Oleksandr Roik, Olexiy Yakovenko, Volodymyr Kazimirov
Powdered samples of anorthite and tialite were carefully grounded in the agate mortar. The resulting powders were remelted in platinum–iridium crucibles at 1700°C. Tamman furnace with heating in a stream of purified argon was used for melting and annealing of samples. A more detailed description of sample preparation is given in [26,27]. The contents of the crucible were released from melting by a diamond instrument with a working diameter much smaller than the diameter of the crucible. Harts of samples bordered with the walls and bottom of the crucible were not used in experiments. The composition of the obtained samples is presented in Table 1.
Mechanical properties and performances of contemporary drug-eluting stent: focus on the metallic backbone
Published in Expert Review of Medical Devices, 2019
Ply Chichareon, Yuki Katagiri, Taku Asano, Kuniaki Takahashi, Norihiro Kogame, Rodrigo Modolo, Erhan Tenekecioglu, Chun-Chin Chang, Mariusz Tomaniak, Neville Kukreja, Joanna J. Wykrzykowska, Jan J. Piek, Patrick W. Serruys, Yoshinobu Onuma
Platinum has been used several years as an alloy for coronary stent [40]. Its biocompatibility and corrosion resistance are attractive for the use as a stent platform. Platinum-Iridium alloys was initially used for coronary stent production. These alloys enhanced the radiopacity of coronary stent due to their high density (Table 1). Compared with stainless steel, the corrosion resistance was improved with Platinum-iridium alloys. In addition, platinum-iridum alloys are MRI-safe and cause less artifact than stainless steel [37,41]. Despite several theoretical advantages, platinum-iridium had limited mechanical properties for coronary stents due to the high rate of recoil [42].
Synthesis, catalytic, cytotoxic, and antibacterial properties of new Ru(II) and Pd(II) complexes bearing bidentate Schiff base ligand
Published in Inorganic and Nano-Metal Chemistry, 2021
Gizem Selvi, Fethi Ahmet Ozdemir, Gurkan Aykutoglu, Namık Özdemir, Zafer Şerbetçi, Muharrem Dinçer, Osman Dayan
The platinum-group metals (platinum, iridium, osmium, palladium, rhodium, and ruthenium) have special properties compared to other TM in terms of catalytic and biological activities.[24–42] Especially, the Ru and Pd complexes are broadly used as catalysts for many organic reactions such as C–C coupling, hydrogenation, esterification, oxidation, C–H bond activation, etc.[43–48] Nowadays, there is interest in the preparation of novel Ru or Pd catalysts to remove dye from wastewater.[49–53] From this perspective, the degradation of Eosin yellow (EY) which is used in medicine, biological science, cosmetics, drugs, and pigments is important.[54,55] There are very rare studies about heterogeneous catalytic degradation of EY in the literature.[56,57] On the other hand, they are attractive for the preparation of new anticancer agents. Ru(II) complexes that exhibit low toxicity and high selectivity are used as anticancer agents at the laboratory and clinical level.[58] Additionally, many palladium complexes show excellent cytotoxicity.[59,60] Moreover, both Ru(II) and Pd(II) complexes bearing SB ligands have good antibacterial effect.[61,62] Recently, we showed that an arene–Ru(II) complex bearing NO-type SB ligand with sulfonate ester group had good cytotoxic and antibacterial effect and catalysts toward degradation/reduction of organic compounds in water.[6,63]