A study of the precision by three methods of gamma-ray photopeak integration has been carried out. COVELL's, total peak area method and the proposed method have been considered. The latter was considered to be the most advantageous because of its relatively high precision and simplicity.
Neutron activation analysis (NAA) for the determination of some trace elements in biological materials is described. The method presented permits the simple and rapid determination of Se, Ag, Au, Sb, Pt (via199Au), Hg, Co, Ni (via58Co), Fe, Zn, Mo, Sn, Cr, Cd, Cu and As after radiochemical separation from Na, K, Cs, Rb and partially Br. For this purpose, postirradiation separation by extraction with mercury or zinc amalgam was used. Separation of gold by extraction with ethyl acetate or by precipitation with dimethylglyoxime was applied for the determination of gold and platinum in biological materials.
A study of the precision and accuracy attainable by several methods of gamma-ray peak integration has been carried out. Covell's total peak area (TPA) methods and a method using interpolated Lagrange polynomials have been considered. The last method described here uses a higher order polynomial for the nonlinear base line construction. The proposed method was considered to be the most advantageous because of the relatively high accuracy and precision obtained.
The scavening of OH· radicals by 2- and 6-mercaptopurines (2-MP and 6-MP) and purine was studied spectrophotometrically using the competition method. The air-saturated aqueous solutions of these compounds in the presence of p-nitroso-N,N-dimethylaniline (NDMA) were -irradiated (-source—60Co). The absolute rate constants for the scavening of OH· radicals by 2-MP and 6-MP were calculated. Main product as produced by irradiation of 2-MP was identified.
The interaction of inorganic silver (as AgNO3) with SeO2 and Se-compounds was studied. Instrumental neutron activation analysis (INAA) was applied as the analytical method. Organ concentrations of Ag were always significantly higher 72 hours after simultaneous intraperitoneal injections with AgNO3 and Se-compounds. Moreover, simultaneous injections elevated the Se-content in organs examined. We suggest that Se-compounds protect against liver lesions by markedly decreasing the concentration of Ag in this organ 2 hours after simultaneous injections. It was also found that Ag supply affects the contents of Zn, Rb, Fe and Co.
The interaction of inorganic mercury (as HgCl2) with SeO2 and organic Se-compounds is compared. Instrumental neutron activation analysis (INAA) was applied as the analytical method. Organ concentrations of Hg and Se were always significantly higher after simultaneous i. p. injections with HgCl2 and Se-compounds. Especially high abundances of Se and Hg in mice organs were found after simultaneous injection with Se-methionine and HgCl2. We suggest that Hg2+ ions are bonded by selenohydryl groups of the metabolites of injected Se-compounds. Binding yield of Hg2+ ions with metabolites of Se-compounds depends upon the chemical form of injected Se-compounds. Variations in the content of Zn, Co, Fe and Rb were observed in all the investigated organs after a single injection with HgCl2 or Se-compounds. Simultaneous injection with HgCl2 and Se-compounds affects the contents of these elements in comparison with single injections.
The incorporation of Se or Te into some mice organs after injections with selenodiglutathione [(GS)2 Se], seleno-cystine [(CySe)2] or Na2TeO3 in the presence of glutathione (GSH) or cysteine (CySH) has been studied. Variations in the Hg, Zn, Fe, Co, and Rb contents were determined in all the investigated organs after intraperitoneal injections with the above compounds. Instrumental neutron activation analysis was applied as the analytical method. It was found that GSH and CySH increased the Se-content in the organs after the injection with (CySe)2, whereas GSH decreased after (GS)2 Se supply. GSH and CySH changed also the Te distribution. Injections with the above compounds affect the Hg, Zn, Fe, Co and Rb concentrations and these variations depend upon the injected compounds.
Male SAS/4 mice injected intraperitoneally with chromate ions and Se-compounds (i.e. selenodiglutathione, selenocystine, selenomethionine and SeO2). The distribution of Se, Cr, Zn, Rb, Co and Fe in liver, kidneys, spleen, heart, lungs, blood, small intestine and eyes has been studied by instrumental neutron activation analysis. Cr was incorporated in all investigated organs and the efficiency of the Cr-accumulation was affected upon the Se-injection. It was found that the mutual and indirect interaction occurs between injected Se-compounds and chromate ions. On the other hand, the interaction of Cr with Zn has been competitive. Injection with chromate ions affects the contents of Rb, Co and Fe in mice organs.
The incorporation of Se into some mice organs after injections of seleno-cystamine [(Se-Cta)2] in the presence of glutathione, cysteine, methionine, cysteamine, 6-mercaptopurine, 2-mercaptopurine and UO
has been studied. Variations in the Zn, Rb, Co, Fe and Hg contents were determined in all examined organs after intraperitoneal injections with the above compounds. Instrumental neutron activation analysis was applied as the analytical method. It was found that injected compounds affect the Se-distribution in the organs examined. Single applied intraperitoneal injection of (Se-Cta)2 or UO
lead to variations in the Zn, Rb, Co, Fe and Hg contents in mice organs.
The contents of Se, Fe, Co, Zn and Rb in several organs of Swiss mice were determined by instrumental neutron activation analysis (INAA) after injections with seleno-methionine (Se-Met) and glutathione (GSH). Se was accumulated in all examined organs and significant effects of the treatment with GSH on the distribution of Se were observed. An increase of Zn (or Se) content in blood after injection with Se-Met (or Zn2+ ions) was observed.