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Optimized atomic absorption spectrophotometry of zinc in cerebrospinal fluid.

This method for direct determination of Zn in cerebrospinal fluid (CSF) involves flame atomic absorption spectrophotometry with a pulse nebulizer technique. Standard solutions of Zn in 150 mmol/L NaCl were used. We could account for 88% of added standard with the method in individual samples from 10 patients and in pooled CSF. The method is acceptably precise, CVs in pooled CSF ranging from 4 to 12%. The mean CSF-Zn concentration for nine healthy men was 0.18 (SD 0.04) mumol/L and for nine healthy women 0.15 (SD 0.03) mumol/L, a statistically insignificant difference. These values are lower than those in previous reports, which may have been the result of contamination problems, nonatomic absorption, or nonstandardized sampling. In the healthy volunteers, the CSF-Zn concentration was positively correlated with serum-Zn, CSF-protein, and CSF-albumin concentrations, as well as with the CSF/serum ratio for albumin.

Adult↗

Improved determination of aluminum in serum by electrothermal atomic absorption spectrophotometry.

This method for determining aluminum in human serum involves electrothermal atomic absorption spectrophotometry. A longer drying time allows less pre-dilution of the sample, and the method also includes a flush cycle after atomization. Standard-addition methodology is used to eliminate matrix effects and the need for a standard curve. We used this method on serum from 50 normal persons and from 34 patients with chronic renal failure who were on long-term intermittent hemodialysis. The mean normal serum aluminum concentration was 6.1 micrograms/L (CV 2.7%), and values for the patients ranged from 13 to 475 micrograms/L.

Aluminum↗

Lead in preserved duck eggs: field screening test and confirmation and quantitation by atomic absorption spectrophotometry and anodic stripping voltammetry.

Analysis of preserved duck eggs in this laboratory by acid digestion and atomic absorption spectrophotometry has shown that addition of lead salts to the egg coating to speed the preservation process results in lead in the egg albumen and yolk. The lead levels decrease as the lead passes through successive membranes, i.e., the lead level in the yolk is lower than that in the albumen. A method has been developed for the field screening of preserved duck eggs for the presence of lead in which a portion of the egg coating is shaken with 4% acetic acid, and the resulting solution is tested by a modification of the AOAC dithizone method. A quantitative method for laboratory confirmation of lead in egg albumen and/or yolk has also been developed in which lead is determined by atomic absorption spectrophotometry or anodic stripping voltammetry after closed-system Teflon-cup digestion with nitric acid.

Animals↗

Effect of the matrix of the standard on results of atomic absorption spectrophotometry of zinc in serum.

Zinc in pooled human serum, diluted 10-fold with demineralized water, was determined by flame atomic absorption spectrophotometry. Recoveries of zinc added to the serum were calculated by use of standards prepared in water, physiological saline, synthetic serum, or dilute HNO3 (10 ml/liter). The flow rates were essentially the same (9.1 to 9.3 ml/min) for water, diluted synthetic serum or actual human serum, and diluted nitric acid. The mean apparent percentage recoveries (plus or minus SD) were the best (102.6 plus or minus 2.5) when the standards were prepared in nitric acid; the values obtained when standards in water were used were too high (111.5 plus or minus 3.9); those with standards prepared in physiological saline (92.0 plus or minus 3.2) or synthetic serum (92.3 plus or minus 2.5) were too low.

Evaluation Studies as Topic↗

Platelet metal levels in normal subjects determined by atomic absorption spectrophotometry.

A method has been developed for the estimation of iron, copper, zinc, calcium and magnesium in human platelets using atomic absorption spectrophotometry. Fe and Cu are either absent or present in very low concentration approaching the limit of detection: Zn, Ca and Mg are readily detectable. EDTA is preferable to ACD(A) or heparin as the anticoagulant for collection in that the platelet yield is reliable: however, slightly low results for Ca and Mg are obtained. Corrections for residual plasma and contaminating red cells are essential. Plasma and platelet metal levels in 33 normal subjects are reported together with the findings in four studies undertaken on platelets obtained from subjects with polycythemia vera.

Adult↗

Determination of ultrafiltrable zinc in plasma by flameless atomic absorption spectrophotometry.

Ultrafiltrable zinc can be determined in small volumes of plasma by using Amicon ultrafiltration membrane cones and either flameless atomic absorption spectrophotometry or 65Zn. The ultrafiltration membrane cone is made sufficiently zinc-free by acid washing, followed by rinsing with de-ionized water. Within-run CVs were 12 and 10%, respectively, for the two methods. Matrix effects are compensated for by using standards in solutions with an inorganic matrix that simulates the sample matrix. Results for ultrafiltrable zinc by the two techniques agreed, and agreed with previously published data obtained by different ultrafiltration techniques. The mean (and SD) percentage of plasma zinc that was ultrafiltrable in 12 control subjects was 1.0 (0.5) by AAS and 0.7 (0.3) by 65Zn.

Humans↗

Comparison of liposome entrapment parameters by optical and atomic absorption spectrophotometry.

Methods for the complete characterization of liposomes prepared by ether-injection are described in detail. The validity of atomic absorption spectrophotometry for measuring markers of trapped volume was checked by comparative determinations of markers with established optical spectrophotometrical methods. The favorable results using atomic absorption spectrophotometry to quantitate the marker Mn2+ are of particular relevance as manganese ion is also the paramagnetic probe in n.m.r. measurements of water permeability of liposomes; our results indicate that in such measurements no other marker need be incorporated.

Liposomes↗

Estimation of zinc concentration of parotid saliva by flameless atomic absorption spectrophotometry in normal subjects and in patients with idiopathic hypogeusia.

The concentraiton of zinc in parotid saliva was estimated by flameless atomic absorption spectrophotometry. As small a sample as 5 to 10 mul of whole paratid saliva can be analyzed quickly and reliably, without special sample handling and with littleinterference from other ions normally found in saliva. Parotid salivary zinc concentration in 34 subjects with normal taste acuity was 51 plus or minus 14 ppb(parts per billion)(mean plus or minus 1 S.D.); parotid salivary zinc concentration in 47 subjectswith idiopathic hypogeusia was 10 plus or minus 6 ppb (mean plus or minus 1 S.D.) which is significantly lower than that in normal subjects (p lessthan 0.001). This technique is a usual method by which to evaluate parotid salivary zinc, particulary inrelationship to problems of taste, appetite, and nutrition.

Ageusia↗

Zinc in plasma, neutrophils, lymphocytes, and erythrocytes as determined by flameless atomic absorption spectrophotometry.

Zinc is determined in neutrophils and lymphocytes (isolated from whole blood on discontinuous gradients of Ficoll-Hypaque) and in microliter quantities of plasma and erythrocytes by flameless atomic absorption spectrophotometry with greater sensitivity than with conventional flame atomic absorption spectrophotometry. Before analysis, neutrophils and lymphocytes are digested with nitric acid and diluted with de-ionized water. Plasma and erythrocytes required no digestion, only dilution. Overall CVs were 4.0, 3.0, 5.0, and 4.6% for neutrophils, lymphocytes, erythrocytes, and plasma, respectively. Matrix effects were fully compensated for by use of standard solutions that simulated the sample matrix. Results for plasma and erythrocytes agreed with those obtained by the conventional technique.

Erythrocytes↗

Semi-automated determination of chromium in whole blood and serum by Zeeman electrothermal atomic absorption spectrophotometry.

Direct determination of normal and elevated levels of chromium in whole blood and serum can be achieved using Zeeman effect electrothermal atomic absorption spectrophotometry. Whole blood and serum levels of chromium were determined for an apparently healthy population and whole blood chromium levels for renal dialysis patients. Blood and serum specimens were diluted with distilled deionized water and Triton X-100. The analyses were performed utilizing air as the alternate gas to facilitate ashing in one of the char steps. Within-run precision studies for whole blood chromium determinations gave relative SD values of 4.75 and 4.65% for 0.358 and 0.172 microgram/l, respectively. Within-run precision studies for the serum chromium analysis yield relative SD values of 5.26 and 2.67% for 0.156 and 0.300 microgram/l, respectively. Detection limits were 0.025 and 0.018 microgram/l for whole blood and serum, respectively. The mean chromium level found in whole blood and serum specimens from apparently normal individuals were 0.371 microgram/l (n = 37) and 0.130 microgram/l (n = 19), with ranges of 0.120-0.673 and 0.058-0.388 microgram/l, respectively.

Autoanalysis↗

[Determination of trace Rh in organic residue by flame atomic absorption spectrophotometry].

The catalytic organic residue contained Rh was digested with HNO3 at 130 degrees C for 12 h. Trace noble metal Rh in catalytic organic residue was determined by flame atomic absorption spectrophotometry. Rh was atomized by air-acetylene flame at lamp Current of 7 mA. The methods of sample pretreatment for Rh in residue were compared in this paper. The recovery rates of this method were 95.3%-105.5% and the relative standard derivation was 0.9%. The method was applied to the analysis of some practical samples and the results obtained were satisfactory.

Acetylene↗

A stationary cold-vapor technique for the determination of submicrogram amounts of mercury in biological tissues by flameless atomic absorption spectrophotometry.

A procedure is provided for the determination of mercury in animal tissue using a single unit stationary cold-vapor generator utilizing atomic absorption spectrophotometry. The entire reduction-absorption cell is fitted to the burner mount on the instrument. Sample digests are introduced into the sample compartment along with reductant, and background corrected absorbance is measured after three minutes of sample-reductant mixing. The method is sensitive to 2 ng Hg (0.50 ng/mL Hg at 0.0044 absorbance units), which corresponds to 25 ng Hg per gram wet tissue using the prescribed digestion procedure. Reproducibility and accuracy are comparable to conventional cold-vapor techniques and the fact that relatively small sample aliquots (4.0 mL) are used for analysis provides for multideterminations of Hg in a single tissue digest; this is not ordinarily possible using conventional cold-vapor methods. A total of 15 digested tissue sample can be analyzed per hour. The method is proposed as an alterative to presently used cold-vapor Hg techniques.

Animals↗

Increased plasma levels of lead in patients with amyotrophic lateral sclerosis compared with control subjects as determined by flameless atomic absorption spectrophotometry.

The levels of lead in plasma were determined in 16 cases of amyotrophic lateral sclerosis (ALS) and 18 control subjects, using flameless atomic absorption spectrophotometry. The mean values were 0.52+/-0.22 microgram/100ml (ALS) and 0.37+/-0.13 microgram/100ml (controls), the difference is statistically significant (5% level). The values in both groups are lower than reported earlier for normal subjects. The findings are discussed against the background of the possible pathogenetic significance of retrograde axoplasmic flow in ALS.

Adolescent↗

Determination of urinary manganese by the direct chelation-extraction method and flameless atomic absorption spectrophotometry.

The direct chelation-extraction method, originally developed by Hessel (1968) for blood lead analysis, has been successfully applied to urinalysis for manganese. The analyses of 35 urine samples containing up to 100 microgram/1 of manganese from manganese-exposed workers showed that the data obtained by this method agree well with those by wet digestion-flame atomic absorption spectrophotometry and also by flameless atomic absorption spectrophotometry.

Chemical Industry↗

Method for the simultaneous determination of cadmium and zinc in whole blood by atomic absorption spectrophotometry and measurement in normotensive and hypertensive humans.

A method is described for the analysis of whole blood cadmium and zinc by extraction and atomic absorption spectrophotometry, in which cadmium is analyzed using a graphite furnace, and zinc using an air-acetylene flame with a single slot burner, after dilution of the extract. Recoveries for cadmium and zinc were 100% and 106%, respectively. For cadmium the day-to-day and within-run coefficients of variation were all less than 13% at low concentrations (approximately 27 nmol/1) and 6% or less at high concentrations (approximately 89 nmol/1). For zinc the coefficients of variation for day-to-day and within-run analyses were less than 6% at low (approximately 76 mumol/1) and high concentrations (approximately 138 mumol/1). The sensitivity of the procedure is 0.5 nmol/1 for cadmium and 1.2 mu mol/1 for zinc. Whole blood from 72 normotensive volunteers, 56 treated hypertensives, and 15 untreated hypertensives were analyzed using this method. Cadmium levels were elevated in smokers but not significantly affected by age or sex. Zinc levels were higher in males than in females, but not significantly affected by smoking. Levels of cadmium and zinc were increased in treated hypertensives and greater still in untreated hypertensives. Significant elevations were found for cadmium in treated hypertensive females who smoked, treated and untreated hypertensive male non-smokers, and for the cadmium to zinc ratio in these later two groups.

Cadmium↗

[Analysis of the content of ten kinds of metal elements in cerebrolysin by atomic absorption spectrophotometry].

The contents of Mg, K, Ca, Cr, Mn, Fe, Co, Ni, Cu and Zn in eight different brand cerbrolysins were determined by flame atomic absorption spectrophotometry. The statistical results as follows: the metal elements have significant difference between in seven kinds of Chinese products and in the cerebrolysin made by Austria. According to the results, we studied the inter relation of metal elements with medicine result, and analyzed the effect of trace elements in cerebrolysin. It provided useful data for medicine on clinical practice.

Amino Acids↗

[Determination of six metal elements in plant Bupleurum scorzoneri folium Willd. by flame atomic absorption spectrophotometry (FAAS)].

The objective in this paper was to determine the amount of metal elements in the Plant Bupleurum scorzoneri folium Willd. by flame atomic absorption spectrophotometry (FAAS). FAAS method was established for the determination of Ca, Mg, Fe, Cu, Zn and Pb in the Plant Bupleurum scorzoneri folium Willd. after digestion with HNO3-HClO4 (V : V= 4 : 1) at 90-95 degrees C and at normal pressure. In the meantime, the optimum parameters of FAAS and the effects of solution medium on the results were studied. The analytical results of Ca, Mg, Fe, Cu and Zn were 5,588.9, 1,790.5, 869.3, 78.4, 44.3 microg x g(-1) respectively, and Pb was not checked out in the samples. The results showed that the recovery of standard addition was 99.57%-102.10%, the relative standard deviation (n= 9) was 0.18%-2.26%. The method is quick, simple and convenient, and the results are satisfactory.

Bupleurum↗

Survey of total and bioavailable chromium in grain and cereal products by atomic absorption spectrophotometry.

The chromium content of samples of cereals, legumes, oil seeds, and alimentary pastes (in the latter, bioavailable chromium as well) was determined by atomic absorption spectrophotometry. The chromium content in whole cereals differs substantially and is mostly concentrated in pericarps. Variations occur not only among different types of cereals, but also among cereals of the same type, depending on the areas of origin. Concentration varies substantially even in samples of legumes and oil seeds. The content of bioavailable chromium (ethanol-extractable) is, in most cases, more than 50% of the total chromium amount. This makes these products particularly interesting as dietary supplements.

Amino Acids↗