Target preparation procedure and PIXE analysis of selenium in different foods consumed in the region of Algiers

A procedure has been elaborated to measure the trace element selenium (Se) in onions and potatoes consumed in the Algiers region. The important chemical pre-concentration step includes wet sample oxidation and the reduction of Se to the element using co-precipitation with tellurium as carrier element and radioactive 75Se to control the chemical process yield. Finally, the filtered probe material is dissolved, labeled with yttrium as an internal PIXE standard and deposited on a thin foil of polycarbonate by solvent drip evaporation. The resulting targets are investigated by the PIXE analysis with 3-MeV proton beams. The low concentration of Se in the samples is determined by measuring the characteristic X-rays.