tellurium has been researched along with tetramethylammonium* in 2 studies
2 other study(ies) available for tellurium and tetramethylammonium
| Article | Year |
|---|---|
Simultaneous Quantification of Iodine and Other Elements in Infant Formula by ICP-MS Following an Acid Digestion with Nitric Acid and Hydrogen Peroxide.
A method for quantifying iodine in infant formula is described. Nitric acid and hydrogen peroxide converted iodine into iodate in microwave-assisted digestion and prevented iodine volatilization and memory effects. Acetic acid as a carbon source was added to both the sample and standard solutions as a countermeasure against carbon charge transfer to iodine and the addition of acetic acid helped to enhance the sensitivity. The instrument limit of quantification was 0.1 ng mL(-1) and the relative standard deviation was less than 3%. The spike recoveries were between 94.8 and 106%. Good agreement with the values obtained using the tetramethylammonium hydroxide method was obtained for infant formula sold in several countries. This method permitted the simultaneous determination of iodine and 12 other important elements (Na, Mg, P, K, Ca, Cr, Mn, Fe, Cu, Zn, Se and Mo) in infant formula. Topics: Acetic Acid; Carbon; Food Analysis; Hydrogen Peroxide; Infant Formula; Iodine; Ions; Limit of Detection; Mass Spectrometry; Microwaves; Nitric Acid; Quaternary Ammonium Compounds; Reproducibility of Results; Tellurium; Trace Elements | 2016 |
Selective inhibition of Zn(2+)-glycerophosphocholine cholinephosphodiesterase by tellurium tetrachloride.
A Zn(2+)-glycerophosphocholine cholinephosphodiesterase (EC 3.1.4.38) purified from mouse brain was found to be reversibly inhibited by tellurium tetrachloride. This effect was characterized by a competitive pattern of inhibition, with apparent Ki values of 0.7 microM and 1.5 microM for the hydrolysis of p-nitrophenylphosphocholine and glycerophosphocholine respectively. Interestingly, the inhibitory effect of tellurium tetrachloride was found to be greatly potentiated by tetramethylammonium salt, indicative of a synergistic interaction between the two compounds. Additionally, it was observed that the effect of tellurium tetrachloride was not affected by a number of other metal ions, and was more pronounced at neutral pH, suggesting that the inhibitory role of the tellurium tetrachloride may be of importance under physiological conditions. Thus Zn(2+)-glycerophosphocholine cholinephosphodiesterase is proposed to be one of the target enzymes which is susceptible to the inhibitory effect of tellurium tetrachloride. Topics: Animals; Brain; Cations, Divalent; Cell Membrane; Edetic Acid; Kinetics; Mice; Phosphodiesterase Inhibitors; Phosphoric Diester Hydrolases; Quaternary Ammonium Compounds; Selenium; Tellurium; Zinc | 1992 |