Potassium tracer studies with

Analysis of Tween 80 was performed using a Hewlett Packard 1100 series HPLC equipped with a Sedex 55 Evaporative Light Scattering Detector (ELSD). The mobile phase consisted of 80% acetonitrile and 20% water. Duplicate injections (5 pL) of each sample were evaluated by HPLC. Potassium iodide, used for the 1-D column and 2-D box tracer studies, was analyzed with a continuous flow Isco V4 variable UV wavelength absorbance detector equipped with an EZChrom Chromatography data acquisition system. 

Becker, J.S., Fiillner, K., Seeling, U.D., Fornalczyk, G., and Kuhn, A.J. (2008) Measuring magnesium, calcium and potassium isotope ratios using ICP-QMS with an octopole collision cell in tracer studies of nutrient uptake and translocation in plants. Anal. Bioanal. Chem., 390, 571-578. 

The majority of PET research involves (ti/2 = 110 min) and (ti/2 = 20 min). With considerable effort, these isotopes can be incorporated into organic molecules such as hormones or drugs. The benefit is that the tracer does not alter the pharmacokinetics of the molecule being labeled in the same way that the conjugation of a metal complex wiU. Nevertheless, applications of metallic PET tracers exist. Rubidium-82 (ti/2 = 1.27 min) has a very short half-hfe but is easily obtained from a strontium-82 generator. The rubidium ion is a potassium analog, and Rb+ is used in myocardial perfusion studies. 

In theory, diffusion coefficients can be measured for any ion. In practice, however, most studies of ionic diffusion in glasses have been restricted to highly mobile ions which have a convenient radioactive isotope for use in tracer measurements. As a result, a majority of the data for ionic diffusion deals with sodium, with lesser amounts of data for potassium, rubidium, and cesium. Studies of lithium are very limited due to the lack of a radioactive isotope of lithium, while studies of divalent and other, more highly charged, ions are restrieted by the very low mobilities of these ions as compared to those of the monovalent ions. 

Treatment of 2,3,4,6-tetra-O-methyl-0 ,j3-D-glucopyranose with 30% hydrogen peroxide in the presence of potassium hydroxide yields the products (2)-(7), thought to arise by decomposition of the hydroperoxide (8), Mechanistic schemes were proposed.The formation of reductic acid from methyl -D-ribo-hexosid-3-ulose by sulphuric acid treatment has been studied by -tracer... 

Some 20 years ago, we carried out a similar study and had similar results giving 40 mg KI two hours before administering a tracer dose of radioactive iodine was associated with an almost complete abolition of the thyroidal uptake in comparison, a dose of 20 mg KI was not as effective. Another interesting point was that when radioactive iodine has already been ingested, it is possible to give potassium perchlorate + TSH injections and... 

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