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1.
Although knowledge of the total concentrations of trace metals in the environment and living organisms is still the essential
starting point for any toxicological evaluation, it is, however, not sufficient to explain the mechanisms responsible for
retention and toxic effect of trace metals. Differentiation between their chemical and biochemical forms is necessary. The
need to resolve the total concentration of trace metals into single chemical species poses great experimental difficulties
and imposes the use of very sensitive analytical techniques for trace metal determinations after specific preseparation procedures
of the different chemical species.
Thus, once the chemical or biochemical metal species have been selectively isolated, the speciation becomes merely an analytical
problem, which requires high sensitivity and accuracy, as well as the evaluation of matrix effects, blanks, contamination,
loss, and sampling.
This paper describes the use of nuclear and radiochemical techniques related to chemical and biochemical speciation problems
at the Joint Research Centre, Ispra, with carrier-free radiotracers and radiochemical neutron activation analysis. 相似文献
2.
Instrumental neutron activation analysis (INAA) and pseudocyclic INAA (PCINAA) have been used to determine the selenium content
of a variety of Canadian food items. Use of the 162-keV gamma ray of short-lived77mSe in INAA allowed relatively simple and rapid determinations and was suitable for many of the foods. PCINAA was found to
give lower detection limits and was used for the low-selenium food samples. Both internal and external quality assessments
were used to evaluate and assure the accuracy and precision of the methods developed. 相似文献
3.
In order to help resolve present inconsistencies of two orders of magnitude or more in reported levels of vanadium in human
serum and blood, a totally postirradiation radiochemical neutron activation analysis (NAA) method was further developed and
applied to some pertinent nanogram and subnanogram reference materials. In particular, the second generation human serum reference
material of Versieck was found to contain a value of 0.67±0.05 ng/g dry wt., corresponding to 0.061±0.005/4/ (see Table 1) ng/mL original fresh serum. Results are also reported for some other appropriate CRMs.
Additionally, a small-scale study in 10 normal subjects (5 m, 5 f) revealed levels similar to those in the serum reference
material and in agreement with the lowest data reported in the literature. Discussion of pitfalls of vanadium determination
and the use of reference materials is included. 相似文献
4.
Naoki Saitoh Takao Suzuki Tohru Kishi Atsuo Iida Yohichi Gohshi 《Biological trace element research》1987,12(1):211-220
Human scalp hair and some kinds of vegetable and animal fibers were analyzed by means of the SR excited X-ray fluorescence
method (SRXFA) and the neutron activation method (NAA). Human hair samples collected from five males and five females were
washed by the IAEA method prior to analysis. In the SRXFA analysis, samples were excited by monochromated X-rays. Fluorescence
X-rays were measured by an Si(Li) detector. The elements detected in all hair samples were S, Ca, Cu, Fe, Zn, Br, and Sr.
The elements K, Ti, Cr, Mn, Ni, Se, Hg, and Pb were also detected in several samples. After SRXFA analysis these same samples
were analyzed by the NAA method. Elements such as Cu, Zn, and Br were detected by both methods, and their relative concentrations
show a good agreement of variation between individuals. However, Pb was only detected by SRXFA, and Na, Au, and Sb were only
detected by NAA. Therefore, these two methods are complementary to each other for trace element analysis. 相似文献
5.
Chen Chunying Zhang Peiqun Hou Xiaolin Chai Zhifang 《Biological trace element research》1999,(1):131-138
Selenium is an important and essential trace element to living systems. In the article, two methods of instrumental neutron
activation analysis and hydride generation-atomic fluorescence spectrometry were applied to determine Se in biological samples
and the accuracy was evaluated by several reference materials. The subcellular distribution of selenium in human liver samples,
which were obtained from normal subjects who had an accidental death, was investigated by differential centrifugation combined
with INAA. Selenium was mainly enriched in mitochondria, nuclei, and cytosol. Almost half of the total Se content existed
in nuclei as a result of the large amount in liver and the high Se concentration. Generally, the highest Se concentration
in the mitochondrial fractions of each liver sample suggested that Se had important functions in this liver component. 相似文献
6.
An epithermal neutron activation method is used to determine the concentration of mineral elements in human dental enamel.
A large number (252) of samples from ancient and modern origins are analyzed. The analytical results are mathematically processed
using a statistical multivariant method. This allows to differentiate deciduous from permanent teeth and decayed from sound
enamel. It is also possible to distinguish the teeth coming from two different necropoles. The origin and the localization
of determined elements in the mineralized part, or in the aqueous-organic part, of enamel is suggested. Their role, as witnessed
in the physiopathological phenomena of dental enamel, is discussed. 相似文献
7.
Park K. S. Kim N. B. Kim Y. S. Lee K. Y. Chun S. K. Yoon Y. Y. 《Biological trace element research》1994,(1):229-237
For a case study of environmental pollution, radiochemical neutron activation analysis (RNAA) was applied to the crucian and
rice collected along the Han River. The crucian was analyzed for three times in 1973, 1987, and 1990. Sixteen trace elements
(Hg, Cd, As, Br, Cu, Na, K, Se, Cr, Hf, Rb, Fe, Zn, Co, La, and Cs) were determined by RNAA using distillation and diethyldithiocarbamate
extraction methods. Contents of Na, K, Se, Hf, Fe, Zn, and Co were almost constant regardless of the sampling place and year.
The contents of the other elements showed increasing trends down river, especially in the first investigation. At the lower
part of the river, the contents showed decreasing trends with the time of sampling, especially during the first two investigations.
These trends were typical for Hg and Cd. Rice was analyzed by the same method for 12 elements, and the results showed no regional
trends, but have decreased after 1973. 相似文献
8.
Edward J. B. Beeley P. A. Bennett L. G. I. Poland J. S. 《Biological trace element research》1990,(1):53-61
A microcomputer-controlled irradiation and measurement system and a microprocessor-controlled sample changer have been installed
at the SLOWPOKE-2 Facility at the Royal Military College of Canada (RMC). These systems can provide the gamut of instrumental
neutron activation analysis (INAA) techniques for the analyst. Custom software has been created for system control, data acquisition,
and off-line spectral analysis using programs that incorporate Gaussian peak-fitting methods of analysis. The design and use
of the equipment is discussed, and the performance is illustrated with results obtained from the analysis of marine sediment
and biological reference materials. 相似文献
9.
Zhong Honghai Tan Minjia Fu Yuliang Huang Jingqing Tang Zhenfang 《Biological trace element research》1999,(1):569-574
In this article, the low-temperature freeze-drying pretreated technique and instrumental neutron activation analysis were
used to determine 29 trace elements in samples of human uterine cancer tissue. The content of these trace elements in uterine
cancer tissue was compared with that in cervicitis tissue and in healthy tissue, respectively. Preliminary results indicated
that significant differences in contents of Au, I, and Se were observed in these tissues. 相似文献
10.
Masuzawa Toshiyuki Suzuki Teruyuki Seki Kayoko Kosugi Tsuyoshi Hibi Yuriko Yamamoto Mineko Takada Jitsuya Matsushita Rokuji Yanada Mitsuru 《Biological trace element research》1999,(1):331-342
Phytoplankton samples were collected during spring bloom of diatoms from three coastal areas of Japan using a NORPAC P-25
net (25-Μm opening) with a NGG52 prenet (335-Μm opening), and 25 major and trace elements have been analyzed by INAA. Concentration
ranges of analyzed phytoplankton samples are much wider than the concentration ranges compiled by Bowen (1979) except for
As, and data of marine phytoplankton samples for Br, Sb, Hf, Sc, La, Ce, Sm, and Eu were not included in the compilation.
The 25 analyzed elements have been categorized into three groups: elements showing positive correlation with Br, positive
correlation with Al, and no positive correlation with Br or Al. The marine phytoplankton samples have been plotted on a Masuzawa-Koyama-Terazaki
(MKT) plot and it proved that the MKT plot is applicable to marine phytoplankton samples. 相似文献
11.
A. N. Garg Vivek Singh R. G. Weginwar V. N. Sagdeo 《Biological trace element research》1994,46(3):185-202
Influence of trace elements in body metabolism and their physiological importance in various diseases have motivated their
accurate and quantitative determination in biological tissues and fluids. Instrumental Neutron Activation Analysis (INAA)
using short and long term irradiation has been employed to determine five minor elements (Cl, K, Na, Mg, P) and 15 trace elements
(As, Br, Co, Cr, Cs, Cu, Fe, Hg, Mn, Rb, Sb, Se, Sc, Sr, and Zn) in cancerous and normal breast tissue from 30 patients of
four clinical stages. Several elements show enhancement in cancerous breast tissue. Selenium shows maximum enhancement of
94.7% followed by K (81.6%), Sc (66.7%), Cu (58.2%), Na (48.5%), P (44.4%), and Zn (39.2%). Some element, such as Fe, Cr,
and Mn, are depressed by 30.8, 30.1, and 12.8%, respectively. These elements compete for binding sites in the cell, change
its enzymatic activity and exert direct or indirect action on the carcinogenic process accelerating the growth of tumors.
This is further evidenced by histopathological examination of cancerous cells showing poor cytological differentiation. An
attempt has been made to correlate trace element concentrations of Se, Cu, Zn, Rb, Br, Hg, As, Co, Fe, Cr, and Mn and the
ratios of Se/Zn, K/P, Cu/Zn, Na/K, and Se/Fe with the clinical stages of cancer. Inhibition of enzymatic activity caused by
variation in trace element concentrations results in immunological breakdown of the body system. 相似文献
12.
Aluminum (Al) determination in human lung tissue, in chemicals for dialysis fluids, and in commercially available dialysis
solutions is carried out using both Instrumental and Radiochemical Neutron Activation Analysis (INAA and RNAA). For some matrices,
pre-and post-irradiation Al separations are tested.
Chelex 100 resin and HDEHP, this latter adsorbed both on teflon and polyurethane foam, are employed for the pre-irradiation
Al separations.
The postirradiation procedures are performed using roughly the same schemes; the conventional Al precipitation as hydroxide
is also carried out.
Al values found in lungs of workers exposed to Al containing dust appear to be much higher than those found for unexposed
people. Chemicals analyzed seem pure enough to give suitable dialysis solutions; for commercially available dialysis fluids,
a 10-fold reduction of Al content should be convenient. 相似文献
13.
Gallorini M. Rizzio E. Birattari C. Bonardi M. Groppi And F. 《Biological trace element research》1999,(1):209-222
The concentrations (ng/m3) of more than 30 trace elements have been determined in the total air particulate matter and in the sizesegregated fractions
collected in urban, industrialized, and rural residential areas in northern Italy by means of a multistage inertial impactor
with the PM10 inlet. All measurements have been carried out by instrumental neutron activation analysis, except for Pb and
Cd, which have been determined by electrothermal atomic absorption spectroscopy. Analytical quality assurance procedures have
been developed with special regard to blanks, reagents, and sampling. Total concentrations and the granulometric distribution
found in the different locations are reported and compared. 相似文献
14.
Park K. S. Kim N. B. Woo H. J. Yoon Y. Y. Lee K. Y. 《Biological trace element research》1990,(1):347-354
For a case study of environmental contamination, radiochemical activation analysis has been applied to the crucians collected
in the Han River. Sixteen trace elements (Hg, Cd, As, Br, Cu, Na, K, Se, Cr, Hf, Rb, Fe, Zn, Co, La, and Cs) were separated
into three groups using distillation and diethyldithiocarbamate extraction methods, and their contents were determined by
a single comparator method. Compared with the values 15 years ago, the values for mercury and cadmium have been drastically
decreased at the middle and lower part of the river, but no typical change is found in other elements. 相似文献
15.
W. D. Ehmann W. R. Markesbery E. J. Kasarskis D. E. Vance S. S. Khare J. D. Hord C. M. Thompson 《Biological trace element research》1987,13(1):19-33
Although the etiology and pathogenesis of Alzheimer’s disease, Pick’s disease, and amyotrophic lateral sclerosis are still
unknown, it has been suggested that perturbations in element metabolism may play a role. Even if not causative factors, these
imbalances may prove to be markers that could aid in diagnosis. We have employed a sequential neutron activation analysis
(NAA) procedure to determine elemental concentrations in brain, hair, fingernails, blood, and cerebrospinal fluid (CSF) of
these patients and age-matched controls. Samples are first irradiated with accelerator-produced 14-MeV neutrons for determination
of nitrogen and phosphorus, then with reactor thermal neutrons for the instrumental determination of 16–18 minor and trace
elements, and, finally, reactor-irradiated again, followed by a rapid radiochemical separation procedure (RNAA) to determine
four additional elements. Major advantages of NAA are: (1) its simultaneous multielement capability; (2) the relative freedom
from reagent and laboratory contamination; (3) the absence of major matrix effects; and (4) an adequate sensitivity for most
elements of interest. Ranges of concentrations by INAA and RNAA in selected control tissues and interelement correlations
in control brain are presented to illustrate results obtained by the procedure. Longitudinal studies of tissues from Alzheimer’s
disease (AD) and amyotrophic lateral sclerosis (ALS) patients are still in progress. 相似文献
16.
Chen CY 《Phytochemical analysis : PCA》2009,20(1):50-57
Optimal conditions for the simultaneous determination of As, Sb and Sm in Chinese medicinal herbs using epithermal neutron activation analysis were investigated. The minimum detectable concentrations of 76As, 122Sb and 153Sm in lichen and medicinal herbs depended on the weight of the irradiated sample, and irradiation and decay durations. Optimal conditions were obtained by wrapping the irradiated target with 3.2 mm borated polyethylene neutron filters, which were adopted to screen the original reactor fission neutrons and to reduce the background activities of 38Cl, 24Na and 42K. Twelve medicinal herbs, commonly consumed by Taiwanese children as a diuretic treatment, were analysed since trace elements, such as As and Sb, in these herbs may be toxic when consumed in sufficiently large quantities over a long period. Various amounts of medicinal herbs, standardised powder, lichen and tomato leaves were weighed, packed into polyethylene bags, irradiated and counted under different conditions. The results indicated that about 350 mg of lichen irradiated for 24 h and counted for 20 min following a 30-60 h decay period was optimal for irradiation in a 10(11)n/cm s epithermal neutron flux. The implications of the content of the studied elements in Chinese medicinal herbs are discussed. 相似文献
17.
Antimony was preconcentrated from natural waters on thionalide-loaded acrylic polymer (Bio-Beads SM-7) from 0.5 m HCl solution.
Prior to the preconcentration, Sb(V) was reduced to Sb(III) with potassium iodide. The antimony retained on the resin was
determined by neutron activation and γ-spectrometric measurement of122Sb (564 keV). The lower limit of detection was 0.023 μg/L for a 100-mL sample. 相似文献
18.
Panayi Antonia E. Spyrou Nicholas M. Ubertalli Livio C. White Mark A. Part Peter 《Biological trace element research》1999,(1):529-540
Methods have been developed for the analyses of trace metals in various areas of porcine brains, (temporal, parietal, frontal
cortex, both right and left hemispheres). Determinations were carried out using inductively coupled plasma-mass spectrometry
(ICP-MS) and electrothermal atomic absorption spectrometry (ETAAS). The elements investigated were Li, Mn, Cu, Zn, Cd, Hg,
and Pb by ICP-MS and Cu, Cd, and Mn by ETAAS. For determination by ICP-MS, a method of standard additions calibration coupled
with internal standards was used, and for ETAAS, standard additions calibrations were prepared. The accuracy of all methods
was determined using NIST and IAEA certified reference material.
A small number of pig brains were analyzed by instrumental neutron activation analysis for Cr, Co, Cs, Fe, Rb, Se, Sc, Sb,
and Zn using the comparator method of analysis. Four separate NIST standard reference materials have been used to examine
the validity of the comparator method. 相似文献
19.
Greenberg Robert R. Kingston H. M. Zeisler Rolf Woittiez Joost 《Biological trace element research》1990,(1):17-25
A preirradiation separation procedure has been developed to separate Al, Cu, Mn, and V from biological materials. Chelex-100
resin is used as the separation medium, and the resin is irradiated directly. Three NIST biological Standard Reference Materials
and five samples of human blood serum, obtained under carefully controlled conditions, have been analyzed by NAA following
this separation. 相似文献
20.
Versieck Jacques Vanballenberghe Lidia Wittoek Ann Vermeir Gerda Vandecasteele Carlo 《Biological trace element research》1990,(1):683-689
A method is described for the determination of mercury in human blood serum and packed blood cells employing neutron activation
analysis. Great attention was devoted to the collection and manipulation of the samples. The accuracy and precision of the
method were tested by analyzing biological reference materials and by comparing the concentrations measured in a number of
serum samples to those obtained by another, independent technique (cold vapor atomic absorption spectrometry) in the same
samples. The article reports the levels measured in blood serum and packed blood cells samples from 15 adult volunteers, as
well as the figures determined in a “second-generation” biological reference material (freeze-dried human serum), prepared
and conditioned at the University of Ghent. 相似文献