Zeeman Atomic Absorption Spectrometer Research Articles

Transformation functions in electrothermal atomic absorption spectrometry

The problem of calibration of an analytical instrument and analysis procedure with an unknown composition and origin of the analyzed sample are considered. The transformation functions of the Zeeman atomic absorption spectrometer with electrothermal atomization have been investigated. The method for establishing a two-parameter transformation function of the spectrometer using a single calibration sample is proposed and the possibility of measuring the analyte concentration in a real sample using the refined transformation function of the spectrometer is considered.

Mercury geochemistry of deep-sea sediment cores from the Kuril area, northwest Pacific

In the present study we report mercury data in the sediment cores obtained during a Germany-Russian and Russian-Germany cruises onboard the Vessels Sonne and Akademik M.A. Lavrentyev in Kuril area. This region cover an extensive area of the Northwest Pacific included the trench system and adjacent abyssal plain, ranging zone off the Kuril Islands. Kuril area is characterized by high water biological productivity, intensive volcanic activity, and hydrological features. Mercury concentrations in sediment cores were analyzed using a Zeeman atomic absorption spectrometer with high frequency modulation of light polarization and a pyrolysis attachment to determine its occurrence, distribution, and deposition flux. Mercury concentrations in the sediments ranged between 8 and 170 ppb; its minimal concentrations (8–15 ppb) were detected in sandy turbidites. For the pre-industrial period, Hg flux ranged between 33 and 36 µg/m2 year. The maximum Hg flux (44 µg/m2 year) corresponded to the 1980, with decreases of up to 30 µg/m2 year in modern sediments (top-core sediment samples). The Hg outlet temperature in the bottom sediments corresponded to a physically sorbed form of Hg and depends on the Hg content of diatoms (siliceous residues). Hg concentrations were significantly positivly correlated with total organic carbon content but negativly correlated with Al, Fe, Zr, and Sr contents. Thus, two main factors affected Hg burial in bottom sediments; atmospheric deposition of Hg and biological productivity. The effect volcanic activity has not been clearly established in this study.

Geochemistry of mercury in surface sediments of the Kuril Basin of the Sea of Okhotsk, Kuril-Kamchatka Trench and adjacent abyssal plain and northwest part of the Bering Sea

Mercury concentrations in surface sediments collected from the Northwestern Pacific were analyzed by mercury Zeeman atomic absorption spectrometer with high frequency modulation of light polarization and a pyrolysis attachment. The range of total Hg concentrations in sediments was 19–158µgkg−1, with a mean of 77µgkg−1 (n = 50). The variation in mercury concentrations in sandy deposits of the slopes was 19–79µgkg−1 Hg; in clayey deposits from the Kuril Basin was 84–130µgkg−1 Hg; in clayey deposits from slopes of the Kuril Basin was 44–84µgkg−1 Hg; in clayey deposits from the abyssal area was 46–116µgkg−1 Hg; and in clayey deposits from the slopes and bottom of the Kuril-Kamchatka Trench was 42–143µgkg−1 Hg.Within the distribution of mercury across the study area, high mercury concentrations were observed in clayey sediments, which are enriched in organic matter and the remains of silicate phytoplankton. The Hg content of sandy deposits was minimal. The level of mercury in our deep-water sediments is somewhat overestimated by comparison to representative background values in clayey sediments from the impact areas (subject to anthropogenic pollution). Anomalies of mercury in bottom sediments near a hydrothermal source (Piip Volcano) have not been observed. The enrichment factor values at the stations range between 0.3 and 4.3. EF values of the most samples were generally more than 1, indicating that enrichment was by biogeochemical processes. Based upon four guideline values (ERL, ERM, ISQG and PEL) we can assume a minimal toxic mercury effect on the benthic marine biota.

Hidden Deficiency of Micronutrients in Apparently Healthy Children of District Bannu, Khyber Pakhtunkhwa, Pakistan

Objective: The present study was designed to analyze the level of micronutrients among apparently normal and healthy children who were randomly selected from various parts of District Bannu, Khyber Pakhtunkhwa, Pakistan in order to evaluate any hidden deficiency of micronutrients malnutrition. Place and duration of the study: The study was designed & compiled in the Department of Biochemistry, Bannu Medical College, Bannu in 2012 while, analytical analysis of the study was carried out at High tech Laboratory, Agriculture university, Faisalabad. Materials and methods: In this cross-sectional descriptive analytical study, micronutrients in blood samples of pre-school children belonging to various areas of District Bannu, Khyber paktunkhwa, Pakistan were determined by Polarized Zeeman Atomic Absorption Spectrometer, Z-8200, Hitachi Japan. Results: Total number of studied population were 100 individuals, out of which 56 % were healthy children with mean age of 49.83 ± 1.78 months, while 7% were overweight with mean age of 57.29 ± 1.55 months, whereas, 7% were obese with mean age of 59 ± 00 months and 30% were underweight with mean age of 36.07 ± 2.94 months respectively. The mean BMI was 15.45 ± 0.16 kg/m2 in the healthy children, 18.32 ± 0.58 kg/m2 in overweight children, 19.69 ± 0.18 kg/m2 in obese children and 11.28 ± 0.32 kg/m2 in underweight children. Mean iron (Fe) levels and the mean Zinc (Zn) levels of overweight and underweight were slightly lower than healthy and obese (P ≥ 0.05) but not statistically significant. Serum Copper (Cu) levels were significantly increased (P<0.05) in under weight and obese individuals. In the age group of <1 year, the overall mean serum Zinc (Zn) contents were 64.30 ± 5.6 μg/dl, serum Iron (Fe) contents were 59.37 ± 5.1 μg/dl, while serum Copper (Cu) contents were 129.09 ± 10.9 μg/dl respectively. In the age group 1-2 years the mean serum Zinc (Zn) contents were 59.10 ± 3.2 μg/dl, the mean serum Iron (Fe) contents were 55.41 ± 3.2 μg/dl and the mean copper contents were 130.68 ± 13.5 μg/dl respectively. In the age group 2-3 years the mean serum zinc contents were 70.24 ± 4.7 μg/dl, The mean serum iron contents were 64.93 ± 4.6 μg/dl and the mean copper contents were 126.70 ± 7.9 μg/dl respectively. Similarly, in the age group 3-4 years the mean serum Zinc (Zn) contents were 46.78 ± 0.7 μg/dl, the mean serum Iron (Fe) contents were 57.94 ± 4.7 μg/dl and the mean Copper (Cu) contents were 109.09 ± 7.9 μg/dl respectively. Result shows that Zinc (Zn) level is high in age group of 2-3yrs and low in the rest of age groups. Similarly, Iron level is found high in 2-3yrs age group and 4-5 yrs age group. The overall mean serum zinc, iron and copper contents among male children were 65.38 ± 1.7 μg/dl, 64.69 ± 2.2 μg/ dl and 113.35 ± 3.2 μg/dl and among female children were 59.09 ± 2.4 μg/dl, 54.23 ± 2.4 μg/dl and 123.23 ± 5.2 μg/dl respectively. The serum Zinc, Iron and Copper levels in children dependent on mixed food were 56.33 ± 3.8 μg/dl, 55.60 ± 5.0 μg/dl and 81.61 ± 8.04 μg/dl, while on bottle feeding it were 60.57 ± 2.03 μg/dl, 58.86 ± 3.3 μg/dl, 112.99 ± 4.6 μg/ dl and on mother milk it were 64.94 ± 3.8 μg/dl, 62.39 ± 2.2 μg/dl and 121.54 ± 3.8 μg/dl respectively. Conclusion: We found low serum iron level in 25% of children, high serum copper level in 12% and low serum copper level in 07% of children while low serum zinc level in 50% of the children. This study provides basic information to allied health professionals, planners, and policymakers and we hope that it will encourage them to find better ways of combating afore mentioned micronutrients.

Arsenic exposure associated with decreased bone mineralization in male

Objective: Arsenic (As) exposure may cause several medical problems. There were a few studies investigated whether it has affected bone tissue in women. However, there was no study in men. The aim of this study was to evaluate associations between bone mineral density (BMD) and As exposure in men subjects.Material and methods: We enrolled in this study 254 subjects who due to chronic As exposure suspected and 82 subjects as a control group. Hair As levels were detected by a hair analysis (Varian AA240Z Zeeman Atomic Absorption Spectrometer, USA). BMD measurements were obtained using dual-energy X-ray absorptiometry instrumentation. We investigated associations between the hair As levels and BMD measurements.Results: The frequency of osteoporosis and osteopenia was found to be 0.8% and 54.5%, respectively, in the As exposure group. The frequency of osteoporosis was found to be 1% and osteopenia was 32.4% in control subjects. There was significant difference between two groups (p < 0.001). Hair As level has a median 1.01 (min: 0.06 and max: 25.71). There were no significant correlation between hair As levels and BMD measurements.Conclusion: According to our observations, As exposure was associated with bone metabolism. Possible cause of osteopenia may be exposure to As. Further investigations are needed to estimate the relationship between As and bone metabolism.

Platinum concentration in sentinel lymph nodes after preoperative intra-arterial cisplatin chemotherapy targeting primary tongue cancer

Conclusion: We conclude that intra-arterially injected cisplatin passed via lymph flow into sentinel nodes (SNs) as the platinum concentration in the SNs was higher than that in the non-sentinel nodes (NSNs). It is possible that preoperative intra-arterial chemotherapy targeting primary cancer also has a therapeutic effect on subclinical metastatic SNs. Objectives: Intra-arterial chemoradiotherapy has been reported to be effective against not only primary tumors but also nodal metastases. We considered the hypothesis that intra-arterially injected cisplatin passed via lymph flow into regional nodes. This study aimed to investigate intra-arterially injected cisplatin distribution to regional nodes by comparing platinum concentrations in SNs and NSNs. Methods: Five patients with T1-2 N0 tongue cancer were treated with preoperative intra-arterial chemotherapy (cisplatin, 100 mg/m2) targeting primary cancer. Partial glossectomy together with SN biopsy and elective neck dissection were performed 2 weeks after intra-arterial chemotherapy. Platinum concentrations in the lymph nodes were measured using a Zeeman atomic absorption spectrometer. Results: Thirteen SNs were harvested together with eight NSNs from the areas adjacent to the SNs. Platinum concentrations were then measured, revealing a significant difference in platinum concentration between the SNs and the NSNs (mean ± SD, 0.682 ± 0.246 µg/g vs 0.506 ± 0.274 µg/g; p = 0.049).

A new Zeeman electrothermal atomic-absorption spectrometer: technology and analysis

The technical parameters and analytical characteristics of a new Zeeman atomic-absorption spectrometer (the Quant Z) are presented. The characteristic masses and the limits of the detection of certain elements of the new instrument are compared with those of similar instruments.

Release of Cobalt and Chromium Ions Into the Serum Following Implantation of the Metal-on-Metal Maverick-Type Artificial Lumbar Disc (Medtronic Sofamor Danek)

Cross-sectional study of 10 patients to measure the serum levels of cobalt and chromium after TDA. To investigate the release of cobalt and chromium ions into the serum following implantation of the metal-on-metal Maverick-type artificial lumbar disc. In total hip endoprosthetics and consequently for TDA (total disc arthroplasty), metal-on-metal combinations are used with the aim of reducing wear debris. In metal-on-metal TDA the release of metal ions has until now been secondary to the main discussion. We investigated the serum cobalt and chromium concentration following implantation of 15 Maverick TDAs (monosegmental L5-S1, n = 5; bisegmental L4-L5 and L5-S1, n = 5; average age, 36.5 years). Five healthy subjects (no metal implants) acted as a control group. The measurements of the metals were carried out using the HITACHI Z-8200 AAS polarized Zeeman atomic absorption spectrometer after an average of 14.8 months. The concentrations of cobalt and chromium ions in the serum amounted on average to 4.75 microg/L (SD, 2.71) for cobalt and 1.10 microg/L (SD, 1.24) for chromium. Compared with control group, both the chromium and cobalt levels in the serum showed significant increases (Mann-Whitney U test, P = 0.0120). At follow-up,the Oswestry Disability Score was on average significantly decreased by 24.4 points (L5-S1) (t test, P < 0.05) and by 26.8 points (L4-S1) (t test, P < 0.05). The improved clinical situation is also represented by a significant decrease of the Visual Analog Pain Scale of 42.2 points after the follow-up (t test, P < 0.05). Significant systemic release of Cr/Co was proven in the serum compared with the control group. The concentrations of Cr/Co measured in the serum are similar in terms of their level to the values measured in THA metal-on-metal combinations or exceed these values given in the literature. Long-term implication of this metal exposure is unknown and should be studied further.

Zeeman atomic absorption spectrometer RA-915+ for direct determination of mercury in air and complex matrix samples

Zeeman mercury spectrometer RA-915+ is suitable for the direct determination (without the preconcentration step in the absorption trap) of mercury concentrations in various samples, such as air, water, soil, food, coal, oil and so on with background levels detection limits. The mercury concentrations were determined by the same RA-915+ spectrometer using different attachments to convert bound mercury to its atomic form. To determine mercury concentrations in samples with complex matrix without pre-treatment (whole blood, hair, crude oil, vegetation, food), a two-chamber pyrolytic atomiser was developed. Its design allows to separate the processes of evaporation and dissociation of mercury compounds as well as to simplify the matrix components in the gaseous phase in real time. Results of analyses of samples with simple and complex matrices are shown in the paper.

Regular variations of the mercury concentration in natural gas

Direct on-line measurements of the mercury (Hg) content in natural gases by a newly developed Zeeman atomic absorption spectrometer RA-915+ have revealed a short-term variability of the Hg concentration, which has not earlier been known. The significant variability of the mercury concentration in a hydrocarbon gas was found in all of the gas wells studied. The variation magnitudes range from 10 to 80% of the average mercury content in the gas. The fluctuations have regular components with periods from few minutes to several hours and can be represented as a set of harmonics with different spectral intensity and stability in time. The most stable harmonics are characterised by intermediate frequencies with periods of 0.3–2.5 h. These ‘basic’ frequencies are characteristic of individual gas wells even within a single productive horizon. The remarkable features of these harmonics are the multiplicity of their periods and good agreement with phases of the Earth's own oscillations. A relatively low-frequency oscillation with a period of 25 h corresponds to a lunar tidal cycle. An oscillatory mechanism of the adsorption–desorption of mercury in a porous gas-bearing medium is assumed to be responsible for these effects.

A longitudinally heated graphite furnace for a longitudinal magnetic field. Formation of absorbance signals

The physical properties and analytical characteristics of a longitudinally heated graphite furnace placed in a longitudinal a.c. magnetic field have been investigated. This graphite furnace is used in a commercially available (Cortech Ltd., Russia, model Z.ETA) Zeeman atomic absorption spectrometer. The analytical signals presented by convolution of the supply and removal functions have been determined for a number of elements (Cd, Pb, Cu, Al, Mo) with various behavioural patterns in a graphite furnace. The release of analyte atoms from the wall of a furnace is described by a first-order rate constant with Arrhenius-type temperature dependence. It has been shown that the supply function is determined mainly by the heating rate of the furnace. At a furnace heating rate of 9.5 K (ms) −1 the atomization time is ∼ 30 ms. A diffusion model of atom transfer satisfactorily predicts the residence time of analyte atoms. The gas temperature has been measured by the two-line method with approximation of the tails of the absorbance pulses by exponential functions. The values of the residence time for the Z.ETA furnace are 100–200 ms. Satisfactory agreement of simulated and experimental absorbance signals has been obtained. Characteristic masses of elements for the Z.ETA furnace have been measured and compared with characteristic mass data for known atomizers.

Molecular Cloning and Expression of Rat Liver Aminopeptidase B

We isolated, by immunological screening of a Uni-ZAP XR cDNA library constructed from rat liver mRNAs, a cDNA clone with 2212 base pairs encoding aminopeptidase B (EC 3.4.11.6). The open reading frame encodes a 649-amino acid protein with a theoretical molecular mass of 72,545 Da and bears the consensus sequence of the zinc metalloexopeptidases, indicating that the enzyme belongs to this family, which includes aminopeptidase A, aminopeptidase N, and leukotriene-A4 hydrolase. Escherichia coli SOLR cells infected with the pBluescript phagemid excised from the Uni-ZAP XR vector containing the aminopeptidase B cDNA had a high L-arginyl-beta-naphthylamidase activity. The recombinant protein was purified to homogeneity from the recombinant E. coli extracts. The enzyme had Cl--dependent aminopeptidase activity specifically restricted to the Arg and Lys derivatives and contained 1 mol of zinc per mol of the enzyme.

Stray light effects in Zeeman atomic absorption spectrometry

A transverse Zeeman atomic absorption spectrometer has been modeled using a polychromatic, optical calculus simulation software program. The models were found to be realistic and greatly facilitated the study of the effects of various Zeeman spectrometer parameters and their interactions. The behavior of the Zeeman spectrometer calibration curves, in the presence of three different types of stray light, was modeled. From the initial results, it seems most likely that the major stray light source in real Zeeman experiments is due to polychromaticity of the light source, even when the source profile is relatively narrow in spectral bandwidth.

Concanavalin A-bound selenoprotein in human serum analyzed by graphite furnace atomic absorption spectrometry

We developed an assay for the direct determination of selenium in serum with a Perkin-Elmer Model 4100ZL Zeeman atomic absorption spectrometer and Ag-Cu-Mg modifier. We used this assay to analyze concanavalin A-bound selenoprotein (CABSP) in human serum after concanavalin A (ConA) affinity chromatography. The CABSP was identified as a single-chain glycoprotein of 57.3 kDa. Carbohydrate units were N- and O-linked to the protein. The selenium moiety was selenocysteine. Total selenium, glutathione peroxidase (GPX; EC 1.11.1.9), ConA-bound selenium (CABS), and alpha 1-acid glycoprotein (AAG) were determined in normal subjects and patients with various pathological conditions. CABS accounted for 44.1% +/- 6.3% of total selenium in sera from normal subjects and 46.5% +/- 3.9% to 55.1% +/- 8.1% in sera from patients with a variety of diseases. Total selenium in serum was well correlated with serum CABS (r = 0.860), but not with serum GPX activity (r = 0.117), for all patients studied. Serum CABS increased in normal subjects after selenium supplementation. Serum CABSP did not behave as an acute-phase reactant, compared with AAG.

Atomic absorption spectrometric detection of biotin-cymantrene as a metallo-tracer for the avidin-biotin system.

Biotin-cyclopentadienylmanganese tricarbonyl (biotin-cymantrene; biotin-Cy) is proposed as a universal metallo-tracer for immunoassays. Associated with the possibility of detecting this type of label (organometallic moieties) along with different analytical procedures, this reagent appears to be a universal system with the advantages of being inexpensive, stable and directly detected (no substrate is required). The optimum conditions for detecting the organometallic label biotin-Cy with a Zeeman atomic absorption spectrometer and the affinity of biotin-Cy for the streptavidin ligand immobilized on the walls of microtitre plates, wells or tubes are described. The results obtained demonstrate the possibility of assaying a wide range of clinical parameters because the detection limit of biotin-Cy is about 1 pg per assay. Based on the competition between immobilized bovine serum albumin adsorbed on the wall and free bovine serum albumin for specific polyclonal antibodies, the streptavidin-metallo-biotin system was tested on a competitive immunoassay model and a satisfactory calibration graph was obtained.

Determination of inorganic and organotin compounds in sea water by graphite furnace atomic absorption spectrometry

Inorganic tin and organotin compounds in artificial sea water were determined at sub-p.p.b. levels. These compounds are separated from matrix elements in aqueous solutions by benzene extraction of their iodide forms from a 2 M sulphuric acid-1.5 M sodium iodide solution containing 1%m/V ascorbic acid. The organic phase was partially vaporised to pre-concentrate the analytes and was injected directly into the treated graphite tube; the signal was measured by a Zeeman atomic absorption spectrometer. Using a matrix modifier, inorganic tin could be directly determined at sub-p.p.m. levels in the presence of organotin compounds.

Deterhination of Dibutyltin and Tributyltin Compounds in Sea Water by Graphite Furnace Atomic Absorption Spectrometry

Abstract Dibutyltin and tributyltin compounds in artificial sea water were determined at sub-ppb levels. These compounds are separated from matrix elements in aqueous solutions by a simultaneous hydride generation dichloromethane extraction. After dichloromethane is vaporized, the residue is dissolved in hexane and is directly injected into the treated graphite tube and the signal is measured by a Zeeman atomic absorption spectrometer.

Cadmium in polymers — Product control in the automobile industry

For the analytical monitoring of the legal cadmium limit for a great number of polymer samples the Adam Opel AG uses an X-ray-fluorescence-spectrometer (XRF) and a suitable Zeeman atomic-absorption-spectrometer (ZAAS) for direct analysis of solid samples. The reasons for this choice of the analytic system are shown and some working conditions are described. Experiences according to the usage of the analytic system and the status of the change-over to the new, from the technical point-of-view, cadmium-free materials are reported.

Use of Zeeman Atomic Absorption Flame Spectrometry for Measurements in C2H2/Air and C2H2/N2O Flames

Abstract The Hitachi Zeeman atomic absorption spectrometer system is used to evaluate the influence of observation height and C2H2 flow rate upon the atomic absorption sensitivity (slope of calibration curve) and upon the atomic absorption signals for 6 elements in an C2H2/Air flame and for 3 elements in an C2H2/N2O flame. Fuel-rich conditions result in greater absorption signals and sensitivities in all cases even though there is a significant temperature drop. Optimal observation heights for each case are evaluated. Greater linearity of analytical calibration curves occurs for fuel-rich conditions under Zeeman background correction than under no background correction. The Zeeman atomic absorption flame spectrometer should find more use in the future.

A new method for direct trace element determinations in solids using a DC plasma as atomizer in a ZAA-spectrometer

A direct Zeeman atomic absorption (ZAA) spectrometer was equipped with a DC plasma as atomizer. Traces in solutions were determined by either direct nebulization into the plasma or with the help of a graphite carrier. For solid samples a locked graphite container was used in which a pressed pellet of the sample was placed. Material leaving the container through a small hole is completely atomized by the plasma. With this method traces of Cd in various sewage sludges and maize were determined without chemical pretreatment.