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We made sensitive and accurate electrothermal atomic absorption spectrometric measurements of vanadium in small volumes of serum. The wet-digested sample was extracted into an organic solvent, with N- benzoyl-N-(o-tolyl)hydroxylamine (BTA) as the chelating reagent. After evaporating the solvent, we dissolved the residue in acetic acid, and injected a 60-microL aliquot into a graphite furnace. In this way we could measure vanadium concentrations as low as 80 ng/L in 4 mL of serum. The within-run CV was 3.3% for serum, 7.7% for urine. Analytical recoveries of vanadium added to serum and urine were 90.3% and 90.8%, respectively. We measured vanadium concentrations in sera from 64 healthy persons (group 1), 15 nondialyzed uremic patients (group 2), and 11 hemodialyzed patients (group 3). The highest concentration of vanadium in group 1 was 240 ng/L; about 60% of the values for this group were less than 80 ng/L. In group 3, the vanadium concentrations were extremely high (15 +/- 14.2 micrograms/L, mean +/- SD), less so (but still above normal) in group 2 (1.58 +/- 3.16 micrograms/L).

We describe an ultrasensitive and reliable method for determining vanadium in human serum by electrothermal atomic absorption spectrometry. After lyophilization, the serum is digested in acid at high pressure, and the digests are evaporated to a small volume. Vanadium in the digests is complexed with cupferron, extracted, and dried. The residue is redissolved in formic acid, where it is 15-fold more concentrated than in the original serum sample. To enhance the furnace sensitivity, we injected six 40-microL aliquots (total, 240 microL) of the concentrated extract. The median concentration of vanadium in 108 persons was 50 ng/L, in good agreement with previously reported results by neutron activation analysis. The characteristic mass obtained (the mass required to give a signal of 0.0044A. s) was 28 pg, the limit of detection 11 ng/L, the limit of quantification 17 ng/L, and the total imprecision (CV) 5.5% at 1.54 micrograms/L. In two assays of Standard Reference Material 1577a (certified vanadium content 99 +/- 8 ng/g), we obtained values of 94.1 and 97 ng/g.

The review considers trace elements including fluorine, copper, manganese, zinc, cobalt, chromium, selenium, molybdenum, tin, vanadium, silicon, and nickel from the standpoint of their role as either inhibitory or causative agents of cancer and also the possible use of their assay in biological fluids as diagnostic or prognostic aids in patients with cancer.

Vanadium has been shown to have a number of insulin-like effects and has been demonstrated to be beneficial in the treatment of streptozotocin-diabetic rats when included in the drinking water. However, some signs of toxicity and vanadium accumulation in all analysed tissues were reported in vanadium-treated animals. In the present study, the effect of repeated intraperitoneal administration of sodium 4,5-dihydroxybenzene-1,3-disulfonate (Tiron), ascorbic acid and deferoxamine mesylate (DFOA) or 2-mercaptosuccinic acid on the distribution and excretion of vanadium was determined in male Sprague-Dawley rats. Rats received sodium metavanadate (NaVO3) or vanadyl sulphate pentahydrate (VOSO4.5H2O) in the drinking water at concentrations of 0.15 mg ml-1 (NaVO3) and 0.31 mg ml-1 (VOSO4.5H2O) for 6 weeks. After the end of this exposure period, chelating agents were administered for 2 weeks (3 days per week) at doses approximately equal to one-tenth of their respective LD50. Urine was collected on days 1, 7 and 14 of treatment. Twenty-four hours after the final chelator injection, rats were killed and vanadium concentrations were determined in various tissues. Tiron and DFOA were effective compounds in mobilizing vanadium after NaVO3 administration, whereas Tiron was the most effective chelator after vanadyl sulphate administration. Ascorbic acid neither increased urinary elimination nor decreased tissue vanadium concentrations.

An HPLC method with UV/VIS and ICP-AES detection is described for the determination of vanadyl porphyrins extracted from biological samples. A detection limit of 50 ng of vanadium was obtained. The method was used to determine these compounds following their extraction from tissues of mussels treated in laboratory experiments and collected during a ?Mussel Watch Programme?. This allowed some conclusions about vanadium speciation in marine organisms to be made. In the tissues of mussels, collected at several sites of the monitored area, which showed high vanadium concentrations, it was possible to establish the presence of this metal in the form of organometallic compounds.

Proton induced X-ray emission (PIXE) and atomic absorption spectroscopy (AAS) were used for vanadium determination in animal tissues. The vanadium concentration levels were determined in blood, kidneys and livers taken from rats. Two groups of the animals were treated with different diets. The diet for the first group was supplemented with vanadium compounds while the diet for the second one was assumed to be a “normal” diet. The second group was treated as control. In order to achieve the best minimum detectable limit (MDL)1 the samples were subject to a special sample preparation procedure. Blood and kidneys were mineralized with an APDC compound. The mineralization process was performed according to the procedure described previously.2 The application of PIXE3 is very useful for different types of samples. PIXE measurements were performed with a proton beam at the Institute of Nuclear Physics in Cracow, Poland while the AAS measurements were done at the Institute of Molecular Biology, Jagiellonian University, Poland. The concentration levels of vanadium in blood and kidneys are compared and discussed. There were no significant statistical differences between results of vanadium concentration levels determined by the abovementioned techniques. The PIXE technique had the advantage over the AAS technique of giving a broad spectrum of trace elements analyzed in a single measurement. Therefore with the help of sample preparation procedure the application of the PIXE method seems to be suitable for such analyzes.