Radioactive compounds preparation

The existence of bismuthine was first demonstrated by using a radioactive tracer, Bi (8). Acid treatment of a magnesium plate coated with Bi resulted in the hberation of a volatile radioactive compound. In subsequent experiments, magnesium bismuthide [12048-46-3], Mg Bi, was treated with acid the yield, however, was only one part of bismuthine for every 20,000 parts of bismuth dissolved. Attempts to prepare bismuthine by reduction of bismuth trichloride with a borohydride have not been particularly successful. Experimental quantities ate best prepared by disproportionation of either methylbismuthine [66172-95-0], CH Bi, or dimethylbismuthine [14381-45-4], C2H. Bi (7) ... 

SI 1962/2711 Radioactive Substances (Prepared Uranium and Thorium Compounds) Order... 

The chemistry of sulfur is a broad area that includes such chemicals as sulfuric acid (the compound prepared in the largest quantity) as well as unusual compounds containing nitrogen, phosphorus, and halogens. Although there is an extensive chemistry of selenium and tellurium, much of it follows logically from the chemistry of sulfur if allowance is made for the more metallic character of the heavier elements. All isotopes of polonium are radioactive, and compounds of the element are not items of commerce or great use. Therefore, the chemistry of sulfur will be presented in more detail. 

Radioactive compounds have been used for radiotherapy and diagnosis in various diseases. Radioactive material is available as a sealed radioactive source. Unsealed sources are usually liquid, particulate, or gaseous. Utmost care is taken in the preparation, handling, and disposal of these radioactive materials, which are very hazardous. 

The analytical accomplishments achieved in the studies of 2,3,7,8-TCDD in human milk are considerable. The detection limits are lower than for any other non-radioactive compound with a high degree of selectivity gained through multi-step sample preparation and highly specific detection. None the less, it is an active area of research into the development of more specific and sensitive measurements. 

PBO was found to be unstable when subjected to add hydrolysis- When JUC -PBO was refluxed with 1 mol L HCl for 1 hour, a single fluorescent radioactive compound was formed. This compound was isolated by preparative high-performance liquid chromatography (IIPLC) and identified by gas chromatography-mass spectroscopy (GC-MS), high-resolution MS, nuclear magnetic resonance (NMR), and comparison of HPLC retention time with a synthetic standard. 

F F compounds prepared from petroleum. The carbon in petroleum is millions of years and many half-lives older than the carbon in growing plants and is no longer radioactive. 

There are two reasons why this sub-section has 1947 in its title. One is that in that year promethium compounds prepared from fission products were fully described (Marinsky et al. 1947) although several radioactive nuclei had been reported... 

A brochure published by the International Atomic Energy Agency lists the commercially available preparations, their specific activities and the manufacturers addresses [312]. The commercially available preparations are often very impure and can be used for chemical and biochemical studies only after careful purification. The classical methods for processing crude synthetic products are generally imsatisfactory when applied to small amounts of radioactive compounds. TLC is particularly convenient for purifying radioactive compounds. A detailed account of such preparative applications of the method is given in a special section of this chapter. 

Radioactive A -hydroxysuccinimide ester of bromoacetic acid is prepared by the procedure described above, but with 30 mCi (33 mg) of the radioactive compound diluted with an equal amount of unlabeled bromoacetic acid. 

A related mechanism of degradation involves the direct interaction of the radioactive emission with other tracer molecules in the preparation. This phenomenon is likely to occur in high specific activity compounds stored at high radiochemical concentrations in the absence of free-radical scavengers. 

Generally, labeled compounds are prepared by procedures which introduce the radionuchde at a late stage of the synthesis. This allows for maximum radiochemical yields, and reduces the handling time of radioactive material. When dealing with short half-life isotopes, a primary consideration is the time required to conduct synthetic procedures and purification methods. 

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