International Journal of PIXE

A standard-free method for hoof samples taken from cattle such as cow, calf, pony and sheep has been developed in order to estimate the state of health of these animals. The standard-free method developed for human nails was confirmed to be applicable to quantitative analysis of hoof samples since the shape of continuous X-rays is almost the same for nail and hoof taken from these ungulate animals. Accuracy and sensitivity of the present standard method were examined by comparing the results with those obtained by an internal-standard method combined with a chemical-ashing method, and it is confirmed that the method is applicable to hoof samples taken from domestic animals of many species. The method allows us to quantitatively analyze untreated hoof samples and to prepare the targets without complicated preparation technique which often brings ambiguous factors such as elemental loss from the sample and contamination of the sample during preparation procedure. It is also confirmed that halogens, which are important elements for estimating the state of health and are mostly lost during chemical-ashing, can be analyzed without problem by the present method. It is found that elemental concentration of more than twenty elements can be constantly analyzed and it is expected to be quite useful in order to estimate the state of health and to make diagnosis of domestic animals. It is also confirmed that elemental concentration of essential elements in hoof is not so changed depending on the positions in the sliced sample along both horizontal and vertical axis.

The standard-free method developed by ourselves 13 years ago has been widely applied to quantitative analyses of hairs such as head hair taken from human and body hair taken from companion and domestic animals. In the present work, the standard-free method for feather and down samples taken from wild birds such as swan, waxwing, osprey, heron and crow is developed. It is found that the standard-free method developed for human hairs can be successfully applied to feather samples without essential modification since the main constituents of feather are almost the same as those for human and animal hairs and, consequently, the shape of continuous X-rays is also the same. Accuracy and sensitivity of the present method were examined by comparing the results with those obtained by an internal-standard method combined with a chemical-ashing method. The method allows us to quantitatively analyze untreated feather samples of very small quantities and to prepare the target without complicated preparation technique. It is expected that the method will become a powerful tool for the studies not only on the mode of life of wild birds but also on environmental contamination by toxic elements.

Proton induced X-ray emission (PIXE) technique has been used for identification and quantitative analysis of the elemental concentration in thick bread samples. Bread samples were air-oven dried at 60 oC and milled in a clean agate mortar to homogenize the sample and pressed into a pellet. PIXE technique relies on the analysis of the energy spectra of the characteristic X-ray emitted from the thick bread sample and the orchard leaf standard (NIST- SRM -1571) bombarded with 2.0 MeV protons. The concentration of the elements (Cl, K, Ca, Mn, Fe, Cu, and Zn) in the bread samples was determined by comparison with NIST orchard leaf standard. The accuracy of the measurements ranged between ± 2% and ± 10% for the most elements detected in this method. The aim of this study is to establish the reference concentration of trace elements in the Iraqi bread using PIXE technique.

In order to investigate the potential cytotoxic effects of particle-induced x-ray emission (PIXE) on tumor cells, 45 MeV proton beam was irradiated on C6 glioma cell lines that had taken up alginate-coated ferrite nanoparticles (Alg-SNP). Cells were anchored in vertical 96-well dishes facing a horizontal beam where the Bragg peak was placed on the upper part of the 96-well dish. Experimental groups included cells without SNP as a control (No-SNP), and cells incubated with SNP for 6 hours (6hr-SNP) or overnight (ON-SNP).

A 0 to 200 Gy proton beam from an MC50 cyclotron (Scanditronix, Sweden) at the Korea Cancer Center Hospital (Seoul, Korea) was used to irradiate each experimental group. Perinuclear Alg-SNP nanoparticle distribution was observed in glioma cells. The test groups (6hr-SNP or ON-SNP) showed an estimated 20-28% (ANOVA, P < 0.05) less cell survival compared to the control group based on MTT assay. Nuclear damage, indicating apoptosis, was present at a higher frequency in the 6hr-SNP and ON-SNP groups up to relatively low radiation dose of 100 Gy by fluorescence microscopy upon Hoechst 33342 and Acridine Orange staining. Ferrite nanoparticles alone were not cytotoxic at the experimental concentration of 0.15 mg/ml. Therefore ferrite nanoparticles may induce additional cytotoxicity from X-ray emission from potential PIXE effects. PIXE and metal nanoparticles may be developed as a therapeutic factor and prodrug for localized proton beam therapy without side effects of solid or disseminate tumors on the surrounding normal tissue.

The present work reports the results of a first study of elemental composition in airborne particulate matter (fine and coarse) collected at the Municipality of Centro Habana, Havana City, Cuba, using the PIXE technique. At present, there is not any information available about element contents in airborne particulate matter from this region. A five months sampling campaign was carried out, collecting the samples under an air flux of 20 l/min with a Gent SFU Sampler equipped with a system which allows the aerosol collection in both size fractions simultaneously. A total of 144 aerosol samples were collected. For the PIXE analysis, the samples were irradiated by 2.0 MeV energy protons from a 2MV Tandetron Accelerator. A total of 14 elements (S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br and Pb) were consistently detected with minimum detection limits from 1 ng/m³ to 10 ng/m³ for most of the elements. Enrichment factors were also calculated for both fractions in order to identify the natural and anthropogenic group of elements. The quantitative results obtained have revealed important information that has been used in a first attempt to understand and to characterize the atmospheric pollution of this area.

The analysis of some of the Indian silver coins during British rule were analysed by Energy Dispersive X-Ray Fluorescence Technique. Eight elements namely Cr, Fe, Ni, Cu, Zn, As, Ag and Pb were estimated in this study which also seems to indicate the fragmentation as well as the impoverishment of the power for the regimes that had produced the studied coins. While Cu and Ag were present as major elements, other elements were found to be present in minor concentration.

The PIXE analysis of glazes and ceramic bodies of a set of architectural glazed ceramics (mostly the zellige mosaics), sampled from seven Moroccan monuments from the 14^th to the 18^th century AD, has been performed. We have identified high lead glazes, opacified with tin-oxide, laid over a calciferous body to produce hard tiles easy to chisel as required by the zellige technique. The analysis has revealed significant differences between the monuments examined: in particular in the formulation of the base glass and in the use of stains to produce coloured glazes. We observed the peculiarity of materials used in Marrakech and we could distinguish, both in terms of glazes and ceramic bodies, the two almost contemporary Madersas dedicated to the sultan Bou Inan, one in Meknes the other in Fez. The PIXE measurements integrate a broad range of spectrometric investigations performed in the past few years.