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1.
A procedure using open digestion followed by flame atomic absorption spectrometry is described for measuring the total selenium
content of Se-enriched yeast. The limits of detection and quantitation were 2.5 mg/L and 5 mg/L Se, respectively. The signal
response was linear over the range of 5–50 mg/L Se, and the average recovery from spiked samples was 98.9%. The validated
method was used to measure the Se content of Se-enriched yeast reference material and produced a result of 2145±38 mg/kg (n=3), which is in good agreement with the certified level of 2125 ±65 mg/kg. 相似文献
2.
Direct determination of selenium (Se) in body fluids by graphite furnace atomic absorption spectrophotometry (GFAAS) may suffer
from problems like severe background, matrix effects, preatomization losses, and spectral interferences. In this study we
evaluate critically the influence on the accuracy of the direct determination of Se in blood plasma and seminal plasma by
GFAAS, and propose a simple, rapid, and accurate method, suitable for routine clinical analysis. The method for blood plasma
is mainly based on studies by the use of matched matrix and a Pd-Ni modifier, but for seminal plasma only a Pd modifier is
required. The method developed was also applied to study the Se distribution in plasma protein fractions of patients with
hepatocellular carcinoma. The Se in plasma of patients was significantly lower than that of the controls. The distribution
pattern of Se in blood plasma fractions of patients was also different from that of the controls. 相似文献
3.
Determination of selenium in the human brain by graphite furnace atomic absorption spectrometry 总被引:2,自引:0,他引:2
Akiko Ejima Chiho Watanabe Hiroshi Koyama Kyoko Matsuno Hiroshi Satoh 《Biological trace element research》1996,54(1):9-21
For the investigation of neurological disorders, a development of simple and accessible methods for determining selenium in
human brain samples is required. We devised a method of determining selenium using graphite furnace atomic absorption spectrometry
(GFAAS). An electrodeless discharge lamp provided the sufficient sensitivity to determine brain selenium. The matrix interferences
were avoided by using high temperature, a prolonged pyrolysis step, and a palladium matrix modifier. The technique of standard
addition was used to evaluate the sample concentrations. The accuracy of the method was confirmed by a bovine liver reference
material. The detection limit of selenium was 0.04 ng. The determined selenium concentrations of human brain cortex and white
matter were higher than those of putamen (115–155 and 206–222 ng/g wet wt, respectively). These GFAAS values agreed with those
obtained by fluorometric analysis (r=0.91,n=10). Moreover, the GFAAS values were compatible to those reported by other researchers (99–274 ng/g wet wt), in which selenium
concentrations in putamen also tended to be higher than the other two regions. We conclude that GFAAS is useful for selenium
analysis in brain samples. 相似文献
4.
Philippe Chappuis Joël Poupon Jeanne-Françoise Deschamps Pierre-Jean Guillausseau François Rousselet 《Biological trace element research》1992,32(1-3):85-91
Several authors have already underlined chromium implication in glucose and lipids metabolism of humans. In this field, physiological
chromium determination in serum could be helpful, but the discrepancies reported in numerous papers are confusing. Here we
report some results obtained by Zeeman correction Graphite Furnace Atomic Absorption Spectrometry: This technique includes
a dilution of serum with 12.5 mM ultrapure nitric acid and 0.25% Triton X-100 (final concentrations). Some main features can be outlined: (1) the contamination
constitutes a serious drawback and (2) the sensitivity of the technique is critical (characteristic mass found: 1.76 pg/0.0044
A.s). Our results obtained from 27 healthy subjects (2.01±0.77 nmol/L) agree with most recent studies and indicate that serum
chromium level does not seem to be sex-related. 相似文献
5.
A simple and reliable method is described which combines ultrafiltration technique with atomic absorption spectrophotometry
to determine the Zn fractions in human blood plasma and seminal plasma. Ultrafiltrable, loosely bound, and firmly bound Zn
can be measured using this method in the presence or absence of ethylene-diaminetetraacetic acid (EDTA). The YMT membranes
for the ultrafiltration must be rinsed thoroughly before use. In contrast to Zn in blood plasma, a large part of Zn in the
seminal plasma was found to be ultrafiltrabe. This method can be applied to study the physiologically active part of Zn in
body fluids related to various disease states. 相似文献
6.
Rosa Sab Roser Rubio Lydia García-Beltrn 《Journal of trace elements in medicine and biology》2003,17(2):73-77
The dual aim of the present study is the investigation of the stability of plasma samples for selenium determination with time and temperature and the assessment of the calibration method. A comparative study is performed, using two calibration methods: standard addition to each sample and matrix matched curve. Our findings show that, in general, significant differences in the selenium content are observed when comparing the results obtained with these two calibration methods. Plasma samples stored at -20 degrees C are stable relative to the selenium content for a period of at least one year. 相似文献
7.
Selenium determination in biological fluids using Zeeman background correction electrothermal atomic absorption spectrometry 总被引:1,自引:0,他引:1
Procedures for the direct determination of total selenium in urine, serum, and blood using electrothermal atomic absorption spectrometry are presented. In the selected experimental conditions, Zeeman correction is mandatory to compensate for the high background signals. The sample diluted and containing 0.1% (w/v) Triton X-100 is introduced directly into the electrothermal atomizer. A solution containing 15% (w/v) hydrogen peroxide, 0.65% (w/v) nitric acid, and 0.5% (w/v) nickel is injected separately into the atomizer. Calibration is carried out using the standard additions method. The detection limit is 30 pg selenium. If palladium, instead of nickel, is used as the chemical modifier, calibration can be carried out against aqueous standards, and the detection limit is 45 pg. In this case, three separate injections are required to prevent precipitation problems in the automatic injector. The reliability of the procedures is checked by analyzing three certified reference materials and by recovery studies. Mean recoveries are 99.7% for serum, 99.4% for urine, and 100.8% for blood samples. Relative standard deviation values are +/-4.0% for serum, +/-3.9% for urine, and +/-4.5% for blood. 相似文献
8.
Wael I. Mortada Mohammed M. Hassanien Ahmed A. El-Asmy 《Journal of trace elements in medicine and biology》2013,27(4):267-272
A highly sensitive and selective technique for the speciation of platinum by cloud point extraction prior to determination by graphite furnace atomic absorption spectrometry (GFAAS) was described. The separation of Pt(II) from Pt(IV) was performed in the presence of 4-(p-chlorophenyl)-1-(pyridin-2-yl)thiosemicarbazide (HCPTS) as chelating agent and Triton X-114 as a non-ionic surfactant. The extraction of Pt(II)–HCPTS complex needs temperature higher than the cloud point temperature of Triton X-114 and pH = 7, while Pt(IV) remains in the aqueous phase. The Pt(II) in the surfactant phase was analyzed by GFAAS, and the concentration of Pt(IV) was calculated by subtraction of Pt(II) from total platinum which was directly determined by GFAAS. The effect of pH, concentration of chelating agent, surfactant, and equilibration temperature were investigated. An enrichment factor of 42 was obtained for the preconcentration of Pt(II) with 50 mL solution. Under the optimum experimental conditions, the calibration curve was linear up to 30 μg L?1 with detection limit of 0.08 μg L?1 and the relative standard deviation was 1.8%. No considerable interference was observed due to the presence of coexisting anions and cations. The accuracy of the results was verified by analyzing different spiked samples (tap water, blood plasma and urine). The proposed method was applied to the speciation analysis of Pt in blood plasma and urine with satisfactory results. 相似文献
9.
Cobalt determinations in biological fluids are of great interest in biological or toxicological research programs. Cobalturia
is often chosen as an indicator for a biological monitoring program in occupational exposure to cobalt dusts. The method described
here derives from the IUPAC reference method for nickel determination. It enables cobaltemia and cobalturia to be measured
in small samples (1 mL). The mean usual values for cobalt in biological fluids are very low (2.7 nmol L−1 for serum and 6.7 nmol L−1 for urine), and therefore, thus require an analytical procedure with preconcentration and extraction. The sample is mineralized
by wet acid digestion. After digestion, inorganic cobalt is extracted in form of ammonium pyrrolidine dithiocarbamate complex
into isobutyl methyl ketone and measured in the organic layer by electrothermal atomic absorption spectrometry.
The analytical parameters are described in detail. The extraction output is about 99%. The detection limits are 1.93 and 1.89
nmol L−1 for serum and urine, respectively. Sensitivity (expressed as the concentration that gives a 0.044 absorbance) is 3.4 nmol
L−1 for serum and 3.3 nmol L−1 for urine.
Within-run precision ranged between 3.9 and 2.5% (coefficients of variation) for serum and 4.2 and 1.1% for urine, at 87 and
136 nmol L−1 levels, respectively. Between-run precision ranged between 4.3 and 3.3% (coefficients of variation) for serum and 4.2 and
2.3% for urine, at 87 and 136 nmol L−1 levels, respectively. At very low concentration, 5.7 nmol L−1 for serum and 2.5 nmol L−1 for urine, the between-run precision is, respectively, 19.5 and 28%.
Linearity is effective between 0 and 272 nmol L−1. Interferences and matrix effects are negligible for urine, serum, or plasma samples without hemoglobin. The method is easily
applicable for routine determinations. 相似文献
10.
11.
One of the major threats to patients undergoing maintenance hemodialysis is an increased susceptibility to infections caused by microorganisms, among whichYersinia orListeria are frequently recovered. In patients receiving hemodialysis, iron overload owing to multiple transfusions plays an important role in the mechanisms underlying the susceptibility to bacterial infections, partially mediated by impaired neutrophil function. In order to assess the true role of iron at the cellular level, an AAS method was developed to measure the iron content of granulocytes. Iron levels in the granulocytes were determined in an apparently healthy population and in a population of iron-overloaded renal hemodialysis patients. Granulocytes were isolated by a method modified from Böyum. The analyses were performed using pyrocoated graphite tubes, and in one of the char steps, oxygen was used to facilitate ashing. The mean iron level found in the granulocytes from apparently normal persons was 4.07 fg/cell (n=17) with a CV of 44%; the mean value for the dialysis patient group was 4.59 fg/cell (n=8) with a CV of 37%. There was no significant difference between the two groups,p=0.70. 相似文献
12.
Rapid and direct determination of selenium, copper, and zinc in blood plasma by flow injection-inductively coupled plasma-mass spectrometry 总被引:1,自引:0,他引:1
A flow injection-inductively coupled plasma-mass spectrometry (FI-ICP-MS) with a simple sample preparation procedure was developed
for the determination of selenium, copper, and zinc in blood serum/plasma. A serum/plasma sample was filtered through a 0.45-μm
membrane filter and diluted with a mixture of trace elements in a standard solution (9∶1, v/v). Measurement of the reference
serum sample confirmed the accuracy of our method for selenium, copper, and zinc concentration. In the case of blood plasma
samples obtained from six healthy adult males, the selenium, copper, and zinc concentrations were similar to those of a typical
healthy male in Japan. These results suggest that the sample prepartive procedure coupled with FI-ICP-MS can be used for the
routine determination of selenium, copper, and zinc in human blood serum/plasma. 相似文献
13.
Summary The use of the matrix-modifying tissue-solubilizer didodecyldimethylammonium hydroxide in the Zeeman-AAS determination of traces of Mo, Co, Cu, Mn and Ni in cells ofChromatium vinosum is described. The correlation to data obtained by deproteinization or wet digestion is convincing (r>0.99), and the time needed for sample preparation is reduced from about an hour to a few minutes. 相似文献
14.
Muñoz-Delgado E Morote-García JC Romero-Romero R López-García I Hernández-Córdoba M 《Analytical biochemistry》2006,348(1):64-68
An electrothermal atomic absorption spectrometric procedure for zinc determination in animal tissues is first optimized and then used to measure the metal content of different tissues from normal and dystrophic mice. The procedure involves minimal manipulation of the sample to overcome the severe contamination problems normally associated with the measurement of low zinc levels. The samples (recommended amount 10 mg) are slurried in 2 ml of a 10-mM tetramethylammonium hydroxide solution containing 0.1 g/100 ml silicone antifoam. After mild heating at 60 degrees C for 10 min and homogenization for 1 min, the suspensions are submitted to a 10-fold dilution and then injected into the electrothermal atomizer. Calibration is carried out using aqueous standard solutions of zinc prepared in the same suspension media. The reliability of the whole procedure is verified using three certified reference materials. 相似文献
15.
Jurisić R Vladimir-Knezević S Kalodera Z Grgić J 《Zeitschrift für Naturforschung. C, Journal of biosciences》2003,58(1-2):143-145
Hydride generation atomic absorption spectrometry (HGAAS) was applied for determination of selenium content in dried aerial parts of wild and cultivated Teucrium species (Lamiaceae) growing in Croatia: T. arduini L., T. chamaedrys L., T. flavum L., T. montanum L., T. polium L., and T. scordium L. subsp. scordioides Schreb. Special attention was paid to the wet oxidation procedure for the sample dissolution. The proposed procedure involved microwave-assisted sample digestion using a mixture of HNO3/H2O2. Wild specimens generally had a higher content of selenium, with concentrations of 0.030-0.095 mg/kg of the dry drug. Cultivated plants contained 0.020-0.055 mg Se/kg. 相似文献
16.
An assay for cadmium in whole blood and urine using deuterium background-correction electrothermal atomic absorption spectroscopy (D(2)-ETAAS) was developed. Cadmium (in a 1- to 2-ml sample) was bound to 15 mg anion-exchange resin, interfering ions were removed in a 2-ml Bio-Spin column, and cadmium was extracted into 100 microl 1M nitric acid for analysis. Cadmium in the sample extract was concentrated 7-fold for blood and 10-fold for urine over the starting material. These steps produced cadmium atomic absorption traces with high signal to background ratios and allowed analysis against aqueous standards. At approximately 0.1 ng Cd/ml, mean intra- and interassay coefficients of variation were 11-12%. Cadmium recovery for 0.1 to 0.6 ng added cadmium was 107+/-4% for blood and 94+/-4% for urine (mean+/-SE, n=3). The mean detection limit (mean + 3 x SD of blank) was 0.008 ng/ml for blood and 0.003 ng/ml for urine. Samples from "unexposed" animals including humans ranged from 0.051+/-0.000 to 0.229+/-0.035 ng/ml. Values were approximately 10-fold lower than those obtained by the method of Stoeppler and Brandt using Zeeman background-correction ETAAS. This new high-sensitivity, low-volume assay will be useful for epidemiological studies, even those involving children, and will provide a means to help determine the contribution of cadmium to disease incidence in the general population. 相似文献
17.
Published values for the concentration of Cu in cerebrospinal and intraocular fluids cover a very wide range (0.016 to 1.0 microgram/ml) and include values which are several times higher than those which would be consistent with normal physiology. An atomic absorption spectrophotometer equipped with a graphite furnace was used to measure the Cu concentration in these fluids and in blood plasma of toads, rabbits, and cats. Under standard conditions, these fluids yielded high background absorbance and only fractional recovery of added Cu. Parameters were therefore established which eliminated both the high background and the matrix interference and allowed the determination of Cu in 10-microliters aliquots of diluted blood plasma and undiluted cerebrospinal and ocular fluid samples. Under these conditions the Cu measured in the ocular (0.011 to 0.032 microgram/ml) and cerebrospinal fluids (0.033 to 0.050 microgram/ml) of these three species was lower than most previously reported values and only a small fraction (1-3%) of the concentration of Cu in the plasma of the same animals (0.85 to 1.22 micrograms/ml). 相似文献
18.
Hsien-Yuan Fan Chang-Ching LinLi-Heng Pao 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(19):1643-1646
A rapid, simple and sensitive method was developed for the determination of para-aminohippuric acid (PAH) in rat plasma using liquid chromatography tandem mass spectrometry (LC-MS-MS). Acetaminophen was used as the internal standard. Chromatographic separation was performed using a Symmetry C18 column and the mobile phase was composed of A: 2 mM ammonium formate and 0.1% formic acid in water and B: 2 mM ammonium formate and 0.1% formic acid in acetonitrile (ACN) (A:B, 30:70, v/v). Detection was performed on a triple–quadrupole tandem mass spectrometer using positive ion mode electrospray ionization (ESI) in the multiple reaction monitoring (MRM) mode. The MS/MS ion transitions monitored were m/z 195.2 → 120.2 and 152.1 → 110.1 for PAH and acetaminophen, respectively. Good linearity is observed over the concentration range of 0.1–500 μg/ml. The method was proved to be accurate and reliable and was applied to a pharmacokinetic study in rat. 相似文献
19.
Arti Mishra Sumir Rai Bhalla Sameera Rawat Vivek Bansal Rakesh Sehgal Sunil Kumar 《Biologicals》2007,35(4):277-284
In the present study, Aluminium quantification in immunobiologicals has been described using atomic absorption spectroscopy (AAS) technique. The assay was found to be linear in 25-125 microg/ml Aluminium range. The procedure was found to be accurate for different vaccines with recoveries of external additions ranging between 93.26 and 103.41%. The mean Limit of Variation (L.V.) for both intra- and inter-assay precision was calculated to be 1.62 and 2.22%, respectively. Further the procedure was found to be robust in relation to digestion temperature, alteration in acid (HNO(3) and H(2)SO(4)) ratio used for sample digestion and storage of digested vaccine samples up to a period of 15 days. After validation, AAS method was compared for its equivalency with routinely used complexometric titration method. On simultaneously applying on seven different groups of both bacterial and viral vaccines, viz., DPT, DT, TT, Hepatitis-A and B, Antirabies vaccine (cell culture) and tetravalent DPT-Hib, a high degree of positive correlation (+0.85-0.998) among AAS and titration methods was observed. Further AAS method was found to have an edge over complexometric titration method that a group of vaccines, viz., ARV (cell culture, adsorbed) and Hepatitis-A, in which Aluminium estimation is not feasible by pharmacopoeial approved complexometric titration method (possibly due to some interference in the sample matrix), this newly described and validated AAS assay procedure delivered accurate and reproducible results. 相似文献
20.
Fifteen kinds of common plants, animals, and minerals used as traditional medicines by the Chinese people have been subjected
to analysis by atomic absorption spectrometry for its content of seven metals: lead, cadmium, arsenic, mercury, copper, cobalt,
and manganese. The concentrations of these elements are significantly different according to their vegetal, animal, or mineral
origin. The average values found for lead, cadmium, arsenic, cobalt, and manganese in drugs of mineral origin are higher than
those derived from plants and animals, except for copper, which was higher in drugs of animal origin.
Our results suggest that the user of traditional Chinese crude drugs should be warned of the potential danger of heavy-metal
poisoning because their concentrations seem to be higher than the maximum values allowed by health agencies in several countries. 相似文献