Analysis of trace elements in blood sera of breast cancer patients by particle induced X-ray emission

Trace elemental imbalance in human beings is postulated to exert action, directly or indirectly, on the carcinogenic process. The objective of this study was to evaluate the levels of trace elements in blood sera of breast cancer patients and analyze their alteration with respect to healthy controls. This work was also intended to establish the role played by the trace elements in carcinogenic process. Particle induced X-ray emission (PIXE) technique was used for trace elemental analysis of blood sera of breast cancer patients and healthy controls. The PIXE measurements were carried out using a 2.5?MeV collimated proton beam from the 3 MV Tandem Pelletron accelerator at Institute of Physics, Bhubaneswar, India. On comparing the trace elemental content in the sera of breast cancer patients with those of control subjects, significant variations were observed in the levels of most of the trace elements. The serum levels of almost all the elements except Fe and Cu were observed to be depressed in cancer patients with respect to normal subjects. However, this variation was significant only for Ti (P?<?0.00005), Cr (P?<?0.005), Mn (P?<?0.0005), Ni (P?<?0.01), Zn (P?<?0.000001), and Se (P?<?0.05). On the other hand, significant elevations were observed in serum Fe (P?<?0.05) and Cu (P?<?0.005) levels in cancer patients. The findings presented in this paper give guidelines for future study into the possible roles and interactions of essential trace elements in the breast carcinogenic process.     

Trace element determination in tomato puree using particle induced X-ray emission and Rutherford backscattering

Particle induced X-ray emission (PIXE) and Rutherford backscattering spectrometry (RBS) were used to determine the concentrations of trace elements in samples of 12 tomato puree brands sold in the Mexican market. While RBS offered information about the main elements present in the matrix, PIXE gave results on trace elements. As a whole, data for 17 elements (C, N, O, Na, Mg, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, and Zn) were obtained. To evaluate the results, a comparison with brands from USA, Japan, Colombia, and Chile was carried out, using tomato purees produced following the domestic technology recipe. Additionally, the results were considered in the light of the Codex Alimentarius and the Mexican standard. It was found that all of the brands fall within the limits established by these standards, being of the same order of magnitude as the foreign brands. This revised version was published online in July 2006 with corrections to the Cover Date.     

Influence of sample charging on satellite spectra during particle induced X-ray emission analysis

We demonstrate how the fine structures of particle induced X-ray emission spectra are influenced by build up of charge in insulating materials. We have measured silicon Kα satellite spectra emitted from fused quartz (SiO₂) that had been bombarded with 1.5 MeV He⁺ ions under various conditions of electron shower. For the insulating fused quartz, the diagram line (KL⁰) appears much stronger than the KLⁿ multiple-vacancy satellites (n ⩾ 1) making the satellites difficult to discern. However, when an electron shower is applied to the fused quartz, the diagram line is lowered according to shower conditions and the KL¹, KL² and KL³ satellites appear prominently. Emission of a strong diagram line from insulating fused quartz is principally due to the charging of the sample and its subsequent discharge.     

Elemental composition of hypertrophic scar and normal skin tissue using proton induced X-ray emission

Hypertrophic scars are a particular type of scar that can form after any type of dermal trauma. They are unsightly, red and elevated above normal skin level. At present no-one knows why these scars form and what form the treatment should take. Full thickness hypertrophic skin tissue as well as full thickness normal skin samples, obtained form the Restoration of Appearance and Function Trust (RAFT), Institute of Plastic Surgery, Mount Vernon Hospital, were analysed, using simultaneously both PIXE and RBS, with a 2 MeV proton beam. The epidemis was compared to the dermis on both normal and scarred tissue, and each was compared to the other, to see if there were any variations in elemental composition. In all the samples C, N and O detected by RBS and P, S, Cl, K, Ca, Fe detected by PIXE were found, In the majority of samples Zn and Cd were found, and in a few samples Sn was determined. Significant differences in concentrations, for the elements P, S, K and Cd, between the epidermis and dermis in both hypertrophic scarred and normal skin tissue were found. A difference was also detected between elemental concentrations in normal and scarred skin for the elements Ca, P, S, Fe and Cd.     

Determination of chemical elements in airborne particulate matter collected at Lembang, Indonesia by particle induced X-ray emission

Monitoring the air quality in ambient air is an important step for assessing the air pollution level in one region and its impact to the human health. In this study, the determination of chemical elements concentrations in airborne particulate matter collected in suburban area of Lembang, Indonesia was carried out. Samples were collected using a Gent stacked filter unit sampler in two size fractions of <2.5 μm (fine) and 2.5–10 μm (coarse). Sampling was conducted twice a week for 24 h from January 2008 to June 2009 and 123 pairs of samples were collected. Black carbon was determined by reflectance and chemical elements analysis were performed using particle induced X-ray emission (PIXE). PIXE as one of ion beam analysis techniques is suitable for analyzing particulate matter for its multielemental analysis with good limits of detection. Results showed that none of daily concentrations of PM_2.5 and PM₁₀ exceeded the 24 h Indonesian NAAQS for PM_2.5 and PM₁₀. Chemical elements such as Mg, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Hg and Pb were determined and the correlation between these elements was reported in order to understand the anthropogenic sources of particulate matter.     

Trace element analysis by particle and photon-induced X-ray emission spectroscopy

The analytical use of particle- and photon-induced X-ray emission spectroscopy has become an important tool in trace element analysis, especially when only small amounts of sample material are available. The physical basis, experimental procedure and typical examples are reviewed.     

Determination of metal-binding proteins in soft tissues of rock oyster by neutron activation analysis and particle induced X-ray emission

In this work, we determined the levels of trace metals in protein fractions isolated from rock oysters by neutron activation analysis (NAA) and particle induced X-ray emission (PIXE). Proteins were extracted from mantles and hepatopancreases of rock oysters and fractionated by size-exclusion high performance liquid chromatography (HPLC). The protein fractions from mantles and hepatopancreases are found to be abundant in Fe, Cu, Zn, Mn, Pb, and Ag. HPLC profiles of Fe, Cu, Zn, and Ag indicate that those elements are bound to proteins extracted from mantles and hepatopancreases.     

Determination of elemental and ionic compositions for diesel exhaust particles by particle induced X-ray emission and ion chromatography analysis.

The purpose of this study is to clarify the chemical characterization of PM2.5 and PM10 in diesel exhaust particles (DEP). Sampling of PM2.5 and PM10 in DEP was carried out in November 1999 using an automobile exhaust testing system at the National Traffic Safety and Environment Laboratory, with a diesel truck (engine type: direct injection, displacement: 7,961 cc, carrying weight: 2,020 kg, equivalent inertia weight: 5,600 kg) placed on a chassis dynamometer. Sampling conditions included idling, constant speed of 40 km/h, M-15 test pattern and 60%-revolution/40%-load of maximum power. Samples were collected on a polycarbonate membrane filter (Nuclepore, pore size: 0.8 microm) using a MiniVol Portable Air Sampler (Airmetrics Co., Inc.). The concentrations of several elemental and ionic species in the PM2.5 and PM10 samples were determined by particle induced X-ray emission (PIXE) and ion chromatography analysis. PIXE analysis of the PM2.5 and PM10 samples revealed 15 elements, of which Na, Mg, Si, S, Cl, Ca, Fe and Zn were found to be the major components. Ionic species were Cl-, NO2-, NO3-, SO4(2-), Na+, NH4+, K+ and Ca2+. Concentrations of elements and ionic species under the sampling condition of 60%-revolution/40%-load were highest in comparison with those of the other sampling conditions. The elemental and ionic species data were compared for PM2.5 and PM10; PM2.5 concentrations were 70% or more of PM10 concentrations for the majority of elements, and concentrations of ionic species in PM2.5 and PM10 were almost identical.     

Fractionation analysis of trace metals in humic substances of soils irrigated with wastewater in Central Mexico by particle induced X-ray emission

The Mezquital Valley in Central Mexico has received wastewater from Mexico City for nearly 100 years. Wastewater brings in organic matter and nutrients but also trace metals. Humic substances, the main components of organic soil matter, are responsible for retaining and regulating the mobility of trace metals in soils. In this study, humic substances were extracted from the soil and separated into distinct fractions (humic acids, fulvic acids and humins). The particle induced X-ray emission (PIXE) technique was applied to determine the metal content in bulk soil as well as in humic acids and fulvic acids not soluble in H₃PO₄. In order to assess whether the long-term input of organic matter and metals modifies the metal association with these humic substances, parcels irrigated for three time periods (5, 47 and 89 years) were selected for this study. It was observed that metals such as Zn and Cu are mainly associated with the humic acids. Fulvic acids retain mainly Cr while Pb is distributed among humic and fulvic acids. It was also observed that in general, metal retention by humic substances increases with irrigation time. Depth also affects metal association with the humic substances.     

Determination of rare earth elements by radioisotope induced X-ray emission spectroscopy

A ring-shaped, 10⁹ Bq²⁴¹Am radioisotope source was used for the excitation of K-shell X-rays from rare earth elements (56<Z<64), present in powdered geological material. In order to improve the efficiency of the measurement of these elements in the concentration range down to 10 ppm, the optimum geometry of the system was found. The results obtained are presented and discussed.     

Clinical evaluation of serum neuron-specific enolase levels in patients with lung cancer

Serum neuron-specific enolase (NSE) levels were studied in 105 patients with malignant neoplasms (lung cancer 38, others 67), 13 patients with various benign diseases and 7 healthy adults. The mean serum NSE level in adult control subjects was 7.4 +/- 0.8 ng/ml, and cut off level was decided 10 ng/ml. Serum NSE levels were elevated in 14/38 (37%) of patients with lung cancer and in 14/67 (21%) of patients with the other malignant neoplasms. In patients with benign diseases, serum NSE level was elevated only in one patient with pituitary adenoma. In 7 patients with small cell lung cancer, the positive rate was higher (86%) than in those with non-small cell lung cancer (26%), and serum NSE levels were higher than 25 ng/ml except one case. There was no correlation between serum NSE and CEA (carcinoembryonic antigen) levels in patients with small cell lung cancer, also in patients with lung cancer. The measurement of serum NSE level seemed to be useful for diagnosis in patients with small cell lung cancer.     

PIXE analysis of blood serum of breast cancer patients undergoing successive chemotherapy

Journal of Radioanalytical and Nuclear Chemistry - Particle induced X-ray emission technique was used to obtain the serum elemental profile of healthy subjects and breast cancer patients (BCPs)...     

Analysis of serum and whole blood using NAA for clinical investigation

The concentrations of Cl, K and Na were analyzed in human body fluids (whole blood and serum) using NAA, resulting in the first biochemical baseline values for the Brazilian population. These data permitted us a discussion about the advantages and limitations of using this analytical technique for clinical chemistry.     

Lead determinations in human bone by particle induced X-ray emission (PIXE) and graphite furnace atomic absorption spectrometry (GFAAS)

Chronic lead (Pb) intoxication has been linked to Alzheimer's disease (AD). Lead, like many heavy elements, tends to accumulate in bone. PIXE is a powerful analytical tool which permits the determination of Pb at the g/g level without requiring sample digestion. GFAAS is one of the most sensitive methods for the determination of Pb and is capable of determining ng/g levels in solution. For bone analyses by GFAAS, sample dissolution and a matrix modifier are required. Rib bone samples were analyzed for Pb by PIXE and GFAAS. IAEA Animal Bone (H-5) was used as a secondary standard for Pb with both methods to ensure accuracy. The range of Pb concentrations in human rib bone was 1.4–11.5 g/g for the trabecular surface by PIXE, 1.3–45 g/g for the cortical surface by PIXE, and 1.54–11.75 g/g for whole bone by GFAAS. No significant difference (p>0.05) was found for AD versus control for either surface or for whole bone.     

Determination of trace elements in water by radioisotope alpha-particle induced X-ray emission

An X-ray spectrometric system including²¹⁰Po -particle sources for excitation and a Si(Li) detector has been applied to determine the concentrations of trace elements in water samples. Thin targets were prepared by the evaporation of a known volume of water deposited on a Mylar backing. The system was calibrated using the internal standard method. Relative sensitivities were measured for 16 elements detected by their K, L and M X-rays. The results are compared with theoretical calculations. The minimum detection limits from 0.01 to 0.07 g/ml were obtained for 2000 s analysis time.     

The estimation of sulphur in organic complexes by deuteron induced X-ray emission

The sulphur contents of samples of three types of carrageenan and protein/carrageenan complexes have been determined using simultaneous Deuteron Induced X-ray Emission (DIXE) and Nuclear Reaction Analysis (NRA). The measured relative sulphur contents of the carrageenan samples were in close agreement with those expected from their chemical structures. Analysis of carrageenan precipitated protein/carrageenan complexes, samples not amenable to conventional chemical assays, indicates that precipitation is less efficient at carrageenan levels above 50ppm. At such levels the excess carrageenan remains in solution and represents a waste of a costly resource in a commercial environment.     

Assessment of atmospheric deposition of metals in Ha Noi using the moss bio-monitoring technique and proton induced X-ray emission

Journal of Radioanalytical and Nuclear Chemistry - The concentration of 22 metal elements including Mg, Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, As, Br, Rb, Sr, Zr, Ba and Pb in Barbula...     

Charged particle induced X-ray analysis: A new tool in forensic science

The application of the charged particle X-ray excitation technique (CPXE) to the problem of determination of residues from gun firing is described. Preliminary results indicate that certain elements, including S, Ba, Fe, and Pb can be detected in statistically significant larger amounts on firing hands than on nonfiring hands with 90 to 98% confidence limits. Results for other elements including K, Ca, Sb, Cr, Mn, Ni, Cu, are also discussed. The simplicity on the technique, together with the number of elements detected, offers advantages over other techniques for firearm discharge residue detection.