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PubMed1990

Neutron activation analysis of manganese contents in ordinary hospital meals.

Neutron activation analysis (NAA) was applied to measurement of manganese (Mn) content in food as an example of ordinary hospital meals. The results showed that: 1. NAA permits measurement of Mn with a simple pretreatment procedure in comparison with AAS (atomic absorption analysis). 2. Daily Mn intake was estimated to be about 3 mg from food, and about 4 mg from green tea. Neutron activation analysis (NAA) has been used for measuring various elements under the conditions appropriate for the irradiated or radioactivated subject of analysis. We presently applied NAA to measurement of manganese (Mn) contents in food as an example of ordinary hospital meals with an estimation of daily Mn intake.

Food Analysis↗
PubMedDate not supplied

Monte Carlo simulation of prompt gamma neutron activation analysis using MCNP code.

Prompt gamma neutron activation analysis (PGNAA) is the most direct method of measuring total-body nitrogen. In combination with internal hydrogen standardisation, it is possible to reduce the dependence on body habitus. The uniformity of activation and detection, however, cannot be optimised sufficiently to eliminate the dependence entirely, and so further corrections are essential. The availability of the powerful Monte Carlo code MCNP(4A) has allowed a more accurate analysis of the activation facility, and yields corrections for body habitus and superficial fat layers. The accuracy of the correction is retained as the source-to-skin distance is reduced, although the activation uniformity is thereby degraded. This allows the use of a 252Cf source with lower activity and hence reduces the running cost of the facility.

Adipose Tissue↗
PubMed1978

[Studies on the presence of metal traces in tissue surrounding A.O. angle plates, based on neutron activation analysis (author's transl)].

Using instrumental neutron activation analysis, 11 samples of tissue in contact with A.O. angle plates and 8 samples of fascial tissue were examined for their content of trace elements, half a year to 5 1/2 years after hip joint intertrochanteric osteotomies. Significant increases in the concentrations of the elements Cr, Fe, Co, Ni and Mo, all of which are contained in the A. O. steel plates (V4A steel), were found both in the contact tissue and in the tissue of the fascia lata femoris about 4--8 cm away from the angle plates, whereas the levels of concentration of elements not specific for the alloy in question, namely, Zn, Se, Rb and Cs, were normal or just subnormal. It was possible to prove by means of element correlations that the elements Cr, Co, Ni and Mo are present in constant ratios in those tissue samples which are loaded with traces of metals foreign to the body. However, only the Mo:Cr ratio corresponds to that of the angle plates. The authors considered Ni to be a useful indicator for the degree of metal loading of a tissue, since Ni will normally occur in human tissue in very low concentrations (less than or equal to 10(-6) g/g dry substance) and was identified by the authors--contrary to previous studies--even in the fascial tissue located up to 8 cm away from the contact tissue. Non-linear correlations were found between iron and the other components of the steel, reflecting the complicated regulatory mechanisms governing the presence of iron in the organism. The results of the analysis are discussed in respect of possible long-term action of the implantate components liberated by corrosion, which, in case of long-term implantates might place an overall burden of foreign ions on the body.

Chromium↗
PubMed2002

Comparative analysis of ancient ceramics by neutron activation analysis, inductively coupled plasma-optical-emission spectrometry, inductively coupled plasma-mass spectrometry, and X-ray fluorescence.

The accurate measurement of the maximum possible number of elements in ancient ceramic samples is the main requirement in provenance studies. For this reason neutron activation analysis (NAA) and X-ray fluorescence (XRF) have been successfully used for most of the studies. In this work the analytical performance of inductively coupled plasma-optical-emission spectrometry (ICP-OES) and inductively coupled plasma-mass spectrometry (ICP-MS) has been compared with that of XRF and NAA for the chemical characterization of archaeological pottery. Correlation coefficients between ICP techniques and XRF or NAA data were generally better than 0.90. The reproducibility of data calculated on a sample prepared and analysed independently ten times was approximately 5% for most of the elements. Results from the ICP techniques were finally evaluated for their capacity to identify the same compositional pottery groups as results from XRF and NAA analysis, by use of multivariate statistics.

Journal Article↗
PubMed1982

[Determination of trace elements in freshwater diatoms by neutron activation analysis (author's transl)].

The instrumental neutron activation analysis was applied to the multielemental analysis of the freshwater diatoms taken from the head and lower areas of Tama river. Dry samples of the diatoms were irradiated for 1 minute (for the measurement of short lived nuclides) by pneumatic tube of TRIGA-II reactor of Musashi Institute of Technology, and 12 hours (for the measurement of long lives nuclides) in F ring of TRIGA-II reactor of Rikkyo University. The analytical results of 20 elements in the samples were obtained, and the concentration of Ti showed high values in all the samples. Since it is considered that Ti is absent in algae, these high values indicate that appreciable amounts of river sediment were contained in the samples. Therefore, the analytical results were corrected for Ti contents in the samples. The concentrations of Mg, K, Zn, Mn and Co in the diatoms showed no difference between the two sampling points. The concentrations of Cr, V, As and Sb in the diatoms, however, showed difference between the two sampling points, depending on the river water quality. In Stenopsyche grisepennis, on the other hand, the concentrations of Mn and Co depend on the river water quality, and the concentrations of Cr depend on the amount of diatoms staying in the body. The concentrations of V, As and Sb in the Stenopsyche griseipennis are considered to depend both on the amount of diatoms and river sediment staying in the body.

Animals↗
PubMed2000

Multielement analysis in cereals and pulses by k0 instrumental neutron activation analysis.

The concentrations of some elements in a few varieties of cereals and pulses are determined by Instrumental Neutron Activation Analysis using a single comparator method (k0-standardised NAA method). A total of 15 elements are measured. The method was validated by analysing the Standard Reference Material (SRM-1571) of NIST; the results are within +/-10% of the reported values for the majority of the elements. The measured concentrations of major and minor elements are analysed in terms of the average intake of mineral content and the role of these elements in terms of the nutritional value.

Diet↗
PubMed1980

The present state of in vivo neutron activation analysis in clinical diagnosis and therapy.

In vivo neutron activation has opened a new era of research on the elemental composition of the human body. The techniques currently employed vary widely with respect to sources, moderators, site of activation and detection systems. Sources include cyclotrons, neutron generators and radioactive elements. Both partial body and total body neutron activation analysis (PBNAA and TBNAA, respectively) are commonly used to determine calcium levels. This review examines various aspects of the two techniques for delayed gamma neutron activation and the factors which affect the sensitivity of the measurements, uniformity of the neutron flux density, and the use of moderators. Portions of the body selected for partial body activation analysis are the hand, the arm and the trunk. Such measurement may be particularly useful for studying patients with diseases that affect various parts of the skeleton differently. However, to date, analyses based on TBNAA and PBNAA do not appear to favour one technique over the other. Comparison of the two techniques has to take into account a variety of factors: dose to the patient, cost reliability, availability of source, nature and cost of complementary facilities required, and the degree of expertise needed by the operating personnel. Neutron activation studies of body calcium have provided data useful for the diagnosis and management of a variety of metabolic disorders. Measurement of sodium, chlorine and nitrogen also appear to be useful clinically. A variety of clinical applications are discussed in this review. A recent development is prompt gamma neutron activation analysis, which can be used for the in vivo determination of cadmium in liver and kidney. Total body nitrogen (measured by prompt gamma neutron activation) and potassium measurements serve as indices of protein and muscle mass content, and hence are useful in assessing the roles of diet and nutrition in these body components.

Activation Analysis↗
PubMed1994

Neutron activation analysis of biological samples at the radiochemistry division of IPEN-CNEN/SP.

Neutron activation analysis is a very useful method for determination of a great number of elements in biological samples. At the Radiochemistry Division of the IPEN-CNEN/SP, this method is being extensively applied to study several materials, such as extracts from medicinal plants, human hair, snake venoms, human lungs, food-stuffs, and corn samples. Both instrumental neutron activation analysis (INAA) and radiochemical neutron activation analysis (RNAA) are used to analyze real samples, as well as biological standard reference materials to evaluate the accuracy and precision of the results.

Brazil↗
PubMed1979

Neutron activation analysis of selenium and 17 elements in sediment.

Instrumental neutron activation analysis was performed to determine Na, Mg, Al, Cl, Sc, V, Cr, Mn, Fe, Co, Ni, Rb, Sb, Cs, Ba, Ce and Eu in the Pacific core sediment. Selenium was also determined by neutron activation analysis, by applying a solvent extraction method with 2,3-diaminonaphthalene (DAN) as a post-irradiation procedure, after the wet-ashing of the sediment. Homogeneity of trace constituents in the sediment and neutron flux corrections for accurate determination were also investigated.

Activation Analysis↗
PubMed1994

Monte Carlo modelling of neutron depth dose distributions in optimizing prompt gamma in vivo neutron activation analysis systems.

Optimization of prompt gamma in vivo neutron activation analysis systems is best achieved using Monte Carlo simulation. In this study the modelling of the dimensions and materials for source holders and collimators is described and compared with experimentally derived results where feasible. Results show that valid depth doses are obtained by modelling only the central part of an IVNAA system and that the use of borated paraffin as a reflector provides acceptable thermal fluence and depth dose.

Americium↗
PubMed1983

Advantage of hand bone calcium content measurement by local neutron activation analysis for following up hemodialysis patients.

Hand bone calcium content [Ca] has been measured by local neutron analysis in hemodialyzed patients free of signs of osteomalacia before and 6-12 months after treatment with vitamin D metabolites, and it has been compared to some iliac bone histomorphometric parameters. With 1,25-(OH)2D3 alone, [Ca] increases significantly at the 6th month of treatment (p less than 0.001) but not from the 6th to the 12th month. With 1 alpha-(OH)D3 + 25-(OH)D3 the same phenomenon is observed at the 6th and 12th months of treatment. Before treatment, [Ca] was correlated negatively with the osteoid surfaces (OS) (r = -0.62, p = 0.01) and the number of osteoclasts per square millimeter (Ocl/mm2) (r = -0.79, p less than 0.001). At the 6th month of treatment, [Ca] was still correlated negatively with OS (r = -0.42, p = 0.05) and with Ocl/mm2 (r = -0.60, p less than 0.005). At the 12th month, the two negative correlations decreased but remained significant (r = -0.42, p = 0.05; r = -0.45, p = 0.05). These data suggest that (1) hand bone calcium analysis by neutron activation permits to follow up the peripheral bone mineral content in hemodialyzed patients and (2) the [Ca] increase only observed during the first months of treatment with vitamin D metabolites probably result from an attenuation of secondary hyperparathyroidism.

Adult↗
PubMed1999

Elemental analysis of herbal preparations for traditional medicines by neutron activation analysis with the k0 standardization method.

Medicinal herb preparations prescribed for specific treatment purposes were purchased from markets and were analyzed by instrumental neutron activation analysis with k0 standardization. Then, 500-700 mg of each sample was pelletized under a pressure of six tones and irradiated together with monitors for alpha and neutron flux ratio determinations for about 6 h in a thermal flux of 2.29 x 10(12) n/cm2/s. The accuracy of the method was established by analyzing standard reference materials. Twenty-nine elements, Ag, As, Au, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Mn, Mo, Na, Rb, Sb, Sc, Se, Sm, Sr, Th, U, Yb, and Zn, were measured in all the samples, and Hg was detected in some samples, with good accuracy and reproducibility. The concentration of elements determined was found to vary depending on the composition of the herbs used. Although the trend linking the element of the medicinal plants to its curative abilities could not be clearly determined, this study showed that the toxic elements found in the samples were below the levels prescribed by health regulations. Nevertheless, such data are important to understand the pharmacological action and the exact mechanisms of action and formation of active constituents for each medicinal plant and to decide the dosage of the herbs used in the final formulation.

Neutron Activation Analysis↗
PubMed2003

Optimal conditions for identifying 80Br and 128I in health food Angelica keiskei using rapid epithermal neutron activation analysis.

This study presents an optimal rapid epithermal neutron activation analysis (ENAA) technique, using a 1mm Cd filter in reactor neutron flux, to analyze 80Br and 128I in the roots, stems, and leaves of health food Angelica keiskei (AK). Various sample weights of lichen (IAEA-336) for each portion of AK, under various periods of irradiation and counting, were used to optimize the elemental analysis. Selecting the analytical conditions depends on the minimum detectable concentration (MDC), required sensitivities and the quantitative accuracy of Br and I elements. These findings imply that the MDCs of Br and I, measured under 10min activation and 5min counting followed by 10min decaying, using 350mg of lichen are ideal for elemental analysis. Moreover, each portions of AK were analyzed under optimal conditions. The elemental concentrations of Br, Cl, I, Mg, Mn and Na and their implications are discussed.

Angelica↗
PubMed1999

Multielement analysis of human hair and kidney stones by instrumental neutron activation analysis with the k0-standardization method.

This paper focuses on the evaluation of the k0 method of instrumental neutron activation analysis in biological materials. The method has been applied in multielement analysis of human hair standard reference materials from IAEA, No. 085, No. 086 and from NIES (National Institute for Environmental Sciences) No. 5. Hair samples from people resident in different parts of Malaysia, in addition to a sample from Japan, were analyzed. In addition, human kidney stones from members of the Malaysian population have been analyzed for minor and trace elements. More than 25 elements have been determined. The samples were irradiated in the rotary rack (Lazy Susan) at the TRIGA Mark II reactor of the Malaysian Institute for Nuclear Technology and Research (MINT). The accuracy of the method was ascertained by analysis of other reference materials, including 1573 tomato leaves and 1572 citrus leaves. In this method the deviation of the 1/E1+ alpha epithermal neutron flux distribution from the 1/E law (P/T ratio) for true coincidence effects of the gamma-ray cascade and the HPGe detector efficiency were determined and corrected for.

Citrus↗
PubMed1978

A two-way scanning method for total body in vivo neutron activation analysis.

When determining the total body content of many elements by neutron activation analysis, irradiation and whole body counting by scanning along the length of the body has significant advantages. A neutron source of lower output and a whole body counter using smaller detectors and shielding (than otherwise needed) can provide a high, uniform response for many elements throughout the body. This was previously achieved by making the speed and direction of scanning identical in irradiation and counting (one-way scanning). A simple theoretical model for scanned irradiation and counting is described. The model is used to show that a scanning regime in which both scanning directions are used (two-way scanning) can provide acceptably uniform response for elements having induced activities of a wide range of half-life. This is supported by measurements made using an existing scanning facility for total body in vivo neutron activation analysis. The two-way scanning regime offers the advantages of increased patient comfort, simpler operation and more efficient use of the time available for counting induced activity.

Activation Analysis↗