Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japan Society for Analytical Chemistry  

Herein, we determined the contents of Cu(I), Cu(II), and hydrophobic Cu in natural water using on-site sample treatment, solid-phase extraction (SPE), and inductively coupled plasma mass spectrometry (ICP-MS) analysis. To prevent Cu species changes in the sampling, filtering and preconditioning steps were performed in a closed system using plastic syringes and a disposable membrane filter. Bathocuproin disulfonate (BCS) and ethylenediaminetetraacetic acid (EDTA) were selected as a Cu(I)-selective complexing agent and a Cu(II) masking agent, respectively, whereas ascorbic acid (AA) was used to reduce Cu(II) to Cu(I). Pre-conditioned samples were passed through a hydrophobic SPE column, and the retained Cu species were eluted with ethanol. Subsequently, the eluate was concentrated, and the residue was re-dissolved in 2 M HNO3 and subjected to ICP-MS analysis. No artificial changes of Cu(I) and Cu(II) species were observed at any time, with the analytical detection limit of total Cu and the blank value equaling 0.0008 and 0.0025 μg kg-1, respectively. The developed method was applied to real estuarine, riverine, and seawater samples collected in Tokushima prefecture, Japan.

DOI： 10.2116/analsci.18SBP08

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The acid-base equilibrium of hexamethylenetetramine (hexamine) was analyzed with its effective electrophoretic mobility by capillary zone electrophoresis. Although hexamine is degradable in a weakly acidic aqueous solution, and the degraded products of ammonia and formaldehyde can be formed, the effective electrophoretic mobility of hexamine was measured in the pH range between 2.8 and 6.9. An acid-base dissociation equilibrium of the protonated hexamine was analyzed based on the mobility change, and an acid dissociation constant of pKa = 4.93 ± 0.01 (mean ± standard error, ionic strength: 0.020 mol dm(-3)) was determined. The monoprotic acid-base equilibrium of hexamine was confirmed through comparisons of its electrophoretic mobility with the N-ethylquinolinium ion and with the monocationic N-ethyl derivative of hexamine, as well as a slope analysis of the dissociation equilibrium.

DOI： 10.2116/analsci.32.1327

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC ANALYTICAL CHEMISTRY  

The acid-base equilibrium of hexamethylenetetramine (hexamine) was analyzed with its effective electrophoretic mobility by capillary zone electrophoresis. Although hexamine is degradable in a weakly acidic aqueous solution, and the degraded products of ammonia and formaldehyde can be formed, the effective electrophoretic mobility of hexamine was measured in the pH range between 2.8 and 6.9. An acid-base dissociation equilibrium of the protonated hexamine was analyzed based on the mobility change, and an acid dissociation constant of pK(a) = 4.93 +/- 0.01 (mean +/- standard error, ionic strength: 0.020 mol dm(-3)) was determined. The monoprotic acid-base equilibrium of hexamine was confirmed through comparisons of its electrophoretic mobility with the N-ethylquinolinium ion and with the monocationic N-ethyl derivative of hexamine, as well as a slope analysis of the dissociation equilibrium.

DOI： 10.2116/analsci.32.1327

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The acid dissociation constant of pravastatin was determined under degraded conditions. Pravastatin was degraded in an acidic solution (pH = 2.0) for 5 h, and the degradation solution was subjected to the measurement of the effective electrophoretic mobility by capillary zone electrophoresis. Although the amount of pravastatin decreased by the acid degradation, its acid dissociation constant was successfully determined with the residual pravastatin through its effective electrophoretic mobility. The determined acid dissociation constant value agreed well with the one obtained with freshly prepared solution and with some reported values.

DOI： 10.2116/analsci.31.1193

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE INC  

Objectives: Humans and other living organisms require small quantities of trace elements throughout life. Both insufficient and excessive intakes of trace elements can have negative consequences. However, there is little information on serum level of trace elements in different populations. This study examines serum levels of trace elements in Ethiopian, Japanese, and Vietnamese women.
Methods: Random samples of healthy women who were referred for routine hospital laboratory examinations in the cities of Hanoi, Sapporo, and Gondar were invited to participate in the study. Serum levels of magnesium, zinc, copper, iron, selenium, and calcium were determined using an inductively coupled plasma mass spectrometer. Furthermore, body mass index of each study participant was determined.
Results: The mean +/- SD serum concentrations of zinc (mu g/dL), copper (mu g/dL), iron (mu g/dL), selenium (mu g/dL) and calcium (mg/dL), respectively, were 76.51 +/- 39.16, 152.20 +/- 55.37, 385.68 +/- 217.95, 9.15 +/- 4.21, and 14.18 +/- 3.91 in Ethiopian women; 111.49 +/- 52.92, 105.86 +/- 26.02, 155.09 +/- 94.83, 14.11 +/- 3.41, and 11.66 +/- 2.51 in Vietnamese women; and 60.69 +/- 9.76, 107 +/- 156, 268 +/- 128, 8.33 +/- 3.65, and 11.18 +/- 0.68 in Japanese participants. Ethiopian women had significantly higher level of serum calcium than Vietnamese and Japanese women (both P < 0.05). Although the mean calcium concentration in Vietnamese women was higher than in women from Japan, the difference was not statistically significant (P > 0.05). Furthermore, compared with Japanese women, Ethiopian women had significantly high iron and copper concentrations (P < 0.05). Serum selenium and zinc levels were higher in Vietnamese than Ethiopian women.
Conclusion: The study revealed a remarkable difference in serum concentrations of trace elements in women from different countries, implying differences in trace elements in the food or soil. (C) 2015 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.nut.2015.04.021

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The hydrophobic effect on electrodeposition of an enzyme CotA was investigated. The CotA was electrodeposited on a gold disc electrode modified with an alkane thiol self-assembled monolayer (SAM). The CotA immobilized hydrophobic SAM gold electrodes exhibited a larger electrochemical activity compared with the hydrophilic SAM and bare electrodes. In particular, large current responses were observed in an ethanethiol or a 1-butanethiol SAM gold electrode. In addition, effect of addition of non-ionic surfactant Triton X on the electrodeposition was checked using the SAM gold electrode. The addition of Triton X had a positive effect on the electrodeposition.

DOI： 10.4028/www.scientific.net/amr.1110.291

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In this paper, leaching behavior of metallic species from steel samples in peracetic acid was investigated. We compared the leaching efficiency between peracetic acid and acetic acid to estimate the role of peroxo functional group for the leaching. As a result, peracetic acid enhanced the leaching ability of metallic species from the high speed steel and the alloy steel samples. MoO3, Mo, MO2C, W, WO3, VC and MnO2 were effectively leached by peracetic acid, while the stainless steel had a high resistance against corrosion by peracetic acid.

DOI： 10.1142/S0217984915400382

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japan Society for Analytical Chemistry  

The acid dissociation constant of pravastatin was determined under degraded conditions. Pravastatin was degraded in an acidic solution (pH = 2.0) for 5 h, and the degradation solution was subjected to the measurement of the effective electrophoretic mobility by capillary zone electrophoresis. Although the amount of pravastatin decreased by the acid degradation, its acid dissociation constant was successfully determined with the residual pravastatin through its effective electrophoretic mobility. The determined acid dissociation constant value agreed well with the one obtained with freshly prepared solution and with some reported values.

DOI： 10.2116/analsci.31.1193

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

A speciation method for chromate, selenite, and selenate was developed by high-performance liquid chromatography (HPLC)-fluorometric detection (FL) using a single derivatizing reagent. Chromium(VI) was determined based on the fluorescence intensity of 1H-naphtho[2,3-d][1,2,3]triazole (NAT) derived from 2,3-diaminonaphthalene (DAN) and nitrous ion; the NO2- was generated through a redox process between Cr(VI) and hydroxylamine hydrochloride (HACl). 4,5-Benzopiazselenol (Se-DAN) was also derived from Se(IV) and DAN, and it was resolved from NAT and detected by reversed-phase HPLC-FL operated under a single setting of an excitation and a fluorescence wavelength. Linear ranges of the calibration curve and detection limits were 0-20 mu mol L-1 (correction coefficient: 0.995) and 0.1 mu mol L-1 for Cr(VI), and 0-20 mu mol L-1 (0.995) and 0.2 mu mol L-1 for Se(IV), respectively. Concentration of Se(VI) was estimated from the difference in its concentration between total Se and Se(IV). The analytical procedure for the determination of total Se included a reduction of Se(VI) to Se(IV) with hydrochloric acid and potassium bromide. The linear range of the calibration curve and detection limit for Se(VI) was 0-20 mu mol L-1 (correction coefficient: 0.990) and 0.3 mu mol L-1, respectively. The proposed method was applied to the determinations of Cr(VI), Se(IV), and Se(VI) in a river water sample. Recoveries of Cr and Se species ranged between 98 and 104%, and the relative standard deviations were about 5% at 10 mu mol L-1 levels of the species.

DOI： 10.1246/bcsj.20140109

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This study describes the facile synthesis of platinum nanoparticle-containing porous carbons (Pt/C) by carbonization of freeze-dried agarose gels containing potassium tetrachloroplatinate under a nitrogen atmosphere at 800 A degrees C. By adjusting the ratio between agarose and platinate in the freeze-dried gels, the Pt content in the final Pt/C products could be systematically varied from 0-10 wt.%. Transmission electron microscopy, inductively coupled plasma atomic emission spectrometry, X-ray photoelectron spectroscopy, Raman spectroscopy, and nitrogen physisorption measurements revealed that the Pt/C materials obtained by this method possess high surface areas (350-500 m(2) g(-1)), narrow Pt nanoparticle size distributions (6 +/- 3 nm) and nanocrystalline graphite -like carbon character. By immobilization of glucose oxidase on the surface of a 4 wt.% Pt/C electrocatalyst prepared by this route, a very sensitive amperometric glucose biosensor was obtained (response time < 2 min, sensitivity 1.9 mA M-1; and a linear response with glucose concentration up to 10 mM). The simplicity and versatility of the described synthetic method suggests its application to the preparation of carbon supported noble metal catalysts including palladium/C and gold/C.

DOI： 10.1007/s00604-014-1270-1

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DOI： 10.5455/jeos.20140924105123

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC ANALYTICAL CHEMISTRY  

The ion-association equilibrium of the dipicrylaminate ion (DPA(-)) was investigated in an aqueous solution with alkali metal ions and with its 18-crown-6 ether complexes as pairing cations by capillary zone electrophoresis (CZE). Although DPA(-) is precipitable with the pairing cations of K+ and Cs+ in a homogenous aqueous solution, a low concentration of DPA(-) below its solubility suppressed the formation of the precipitates, and DPA(-) was detected as a usual CZE signal. Changes in the electrophoretic mobility of DPA(-) was analyzed for its ion-association equilibrium. The ion association constants determined were almost comparable among alkali metal ions, while the ion association constants were meaningfully large with a hydrophobic 18-crown-6 ether complex of K+. The CZE separation was also proved to be useful for the equilibrium analysis under precipitating conditions. It was suggested that the precipitable property of DPA(-) with K+ and Cs+ could not be attributed to the ion-association process in an aqueous solution, but to the condensation process concerning the intermolecular CH center dot center dot center dot O bond in the precipitate crystals, as reported.

DOI： 10.2116/analsci.30.919

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC ANALYTICAL CHEMISTRY  

The acid dissociation constants (K-a) of Haloperidol and its degraded product were determined by capillary zone electrophoresis (CZE). Haloperidol is degraded by UV-light irradiation, and 4-(p-chlorophenyl)-4-hydroxypiperidine (CPHP) is generated from Haloperidol. When the irradiated solution was analyzed by CZE, residual Haloperidol and two degraded products were detected. The acid dissociation constant of Haloperidol was determined through the electrophoretic mobility of the residual Haloperidol, and the pK(a) value determined was similar to that measured under no degradation conditions, as well as literature values. It was also confirmed that one of the degraded products was assigned to CPHP based on the migration time, the electrophoretic mobility, and its acid dissociation constant analyzed. It was demonstrated in this study that the acid dissociation constants are accurately determined by using CZE, even under degraded conditions of the analyte.

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Background: Hypocalcaemia, defined by serum calcium level less than 8.5 mg/dl, could be caused by human immunodeficiency virus (HIV) and diarrheal diseases. In Ethiopia, while morbidities from diarrheal diseases and HIV are serious health problems, studies assessing the interactions amongst of the three do not exist. Therefore, the present study was undertaken to investigate the level of calcium among diarrheic patients with and without HIV co-infection.
Methods: Consecutive diarrheic patients attending Gondar University Hospital in Ethiopia were enrolled and screened for HIV, intestinal parasites, Shigella and Salmonella. Concentration of calcium in serum was determined using an inductively coupled plasma mass spectrometer.
Results: A total of 206 diarrheic patients were included in the study (109 = HIV positive, 97 = HIV negative). Intestinal parasites and Shigella species were detected in 32.2% and 8.5% of the patients, respectively. The serum calcium levels in the patients who were found positive for Shigella species or intestinal parasites was not significantly different by the presence or absence of HIV co-infection. HIV infected diarrheic patients had significantly lower mean serum calcium levels (7.82 +/- 1.23 mg/dl) than those negative for HIV (8.38 +/- 1.97) (P = 0.015). The age groups 25-35 and greater than 45 years showed significantly lower mean serum calcium levels (7.77 +/- 1.55 mg/dl) in comparison to the other age groups (7.84 +/- 1.41 mg/dl, P = 0.009). On the other hand, females presented with significantly lower mean serum calcium levels (7.79 +/- 1.60 mg/dl, P = 0.044) than males (8.26 +/- 1.65 mg/dl).
Conclusion: There is high prevalence of hypocalcaemia among diarrheic patients in northwest Ethiopia. And HIV stood out to be a major risk factor for development of hypocalcaemia among the diarrheic patients in northwest Ethiopia. Further studies are required to substantiate and characterize the mechanisms and consequences of calcium metabolism disorders among HIV infected individuals in the study area.

DOI： 10.1186/1471-2458-14-679

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Graphene and chemically modified graphenes were resolved by micellar electrokinetic chromatography (MEKC) using sodium dodecylbenzenesulfonate (SDBS) as a micelle matrix. Graphene was successfully dispersed in a micellar solution, and a consecutive and broad signal was obtained by the MEKC with a 20 mmol dm(-3) aqueous SDBS solution for Graphene Nanoplatelets. Chemically oxidized graphene was less retained to the micelle than the Graphene Nanoplatelets by the proposed MEKC, and they were resolved with each other.

DOI： 10.2116/analsci.29.769

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We fabricated a thermostable quinoprotein aldose sugar dehydrogenase (tPQQ-ASD derived from a hyperthermophilic archaeon Pyrobaculum aerophilum) immobilized electrode. The electrode was prepared by immobilizing agarose gel mixed with the enzyme and carbon nanofiber (CNF) on a carbon paste (CP) electrode containing p-benzoquinone (BQ) as an electron mediator. The electrocatalytic response was clearly observed by the addition of D-glucose at the electrode. The electrode properties such as pH, temperature dependency and substrate selectivity basically followed the enzyme properties. The current response against D-glucose increased with measurement temperatures up to 70 degrees C, and response perturbation caused by dissolved oxygen level was not observed at the electrode. As for the results of long-term stability evaluation, the current response was stable for 30 days when the electrode was stored in HEPES buffer solution (pH 7.0) at 4 degrees C.

DOI： 10.2116/analsci.29.79

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Background: Several micronutrients are essential for adequate growth of children. However, little information is available on multiple micronutrient status of school children in Ethiopia. The present study was designed to evaluate the relationship between multiple micronutrient levels and nutritional status among school children.
Method: In this cross-sectional study, anthropometric data, blood and stool samples were collected from 100 children at Meseret Elementary School in Gondar town, Northwest Ethiopia. Serum concentration of magnesium, calcium, iron, copper, zinc, selenium and molybdenum were measured by inductively coupled plasma mass spectrometer. Anthropometric indices of weight-for-age, height-for-age and BMI-for-age were used to estimate the children's nutritional status. Stool samples were examined by standard microscopic methods for intestinal parasites.
Results: The prevalence of stunting, underweight, wasting and intestinal parasitoses among school children was 23%, 21%, 11% and 18%, respectively. The mean serum levels of magnesium, calcium, iron, copper, zinc, selenium and molybdenum were 2.42 +/- 0.32 (mg/dl), 15.31 +/- 2.14 (mg/dl), 328.19 +/- 148.91 (mu g/dl), 191.30 +/- 50.17 (mu g/dl), 86.40 +/- 42.40 (mu g/dl), 6.32 +/- 2.59 (mu g/dl), and 0.23 +/- 0.15 (mu g/dl), respectively. Selenium deficiency, zinc deficiency and magnesium deficiency occurred in 62%, 47%, and 2% of the school children, respectively. Height-for-age showed significant positive correlation with the levels of copper and molybdenum (p = 0.01) and with the levels of magnesium (p = 0.05).
Conclusion: Deficiencies of selenium and zinc were high among the school children although the deficiencies were not significantly related with their nutritional status. The prevalence of both malnutrition and intestinal parasitism was not negligible. These calls for the need to undertake multicentre studies in various parts of the country to substantiate the data obtained in the present study so that appropriate and beneficial strategies for micronutrient supplementation and interventions on nutritional deficiencies can be planned.

DOI： 10.1186/1475-2891-11-108

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In the present work, we investigated the multielemental elution behavior of metal ions absorbed on iminodiacetic acid (IDA) chelating resin by using hydrogen peroxide (H2O2) as an eluent. As a result, V(V), Mo(VI), W(VI), Nb(V) and Ta(V) were efficiently eluted by H2O2. In contrast, other metal ions were rarely recovered. The oxidation states of V(V), Mo(VI), and W(VI) were not changed through the H2O2 eluting process, checked by X-ray photoelectron analysis. In addition, the UV-vis adsorption spectra and IR spectra of V(V), Mo(VI) and W(VI) in the H2O2 eluent suggested the formation of metal-peroxo complexes through H2O2 elution. The desorption of these metal ions from IDA functional groups is explained in term of destabilization along with the coordination of peroxo-ligands to the V(V)-, Mo(VI)- and W(VI)-IDA complexes, and a decrease in the adsorption capacity by electrostatic repulsion between dissociated carboxylic groups of IDA and the oxoanions in the neutral pH shown in 30 wt% H2O2. When this method was applied to the selective separation of V(V), Mo(VI) and W(VI) from other metals in an acid soluble fraction of fly-ash, 83.4 +/- 2.5% of V(V), 88.1 +/- 3.3% of Mo(VI), and 69.3 +/- 5.4% of W(VI) were recovered in a 30 wt% H2O2 eluent.

DOI： 10.2116/analsci.28.463

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In this study, electrodeposition of thermostable enzyme Bacillus subtilis CotA, which is a laccase and has a bilirubin oxidase (BOD) activity, was investigated. The electrodeposition was operated in a mixture of Bacillus subtilis CotA in the PBS (pH 8.0) and TritonX-100 under applying potential (1100 mV vs. Ag/AgCl for 5 min.). The current response was measured by linear sweep voltammetry technique (LSV). The thermostable enzyme Bacillus subtilis CotA electrodeposited electrode was compared with a mesophile BOD electrodeposited electrode. As a result, the Bacillus subtilis CotA modified electrode showed better sensitivity and long-term stability than the mesophile BOD modified electrode.

DOI： 10.1142/s2010194512003091

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：TRANS TECH PUBLICATIONS LTD  

A silica colloidal crystal obtained by centrifugation at 9 G for 2 days in water was annealed by additional stronger centrifugation at 50 G for 5 days. The number of the striations observed in the colloidal crystal under crossed polarized light decreased at some parts in a growth container after the additional centrifugation, while the number also increased at the other parts. The decrease probably shows the shrinkage of the stacking disorders under high gravity, while the increase probably shows the production of new stacking disorders.

DOI： 10.4028/www.scientific.net/DDF.323-325.555

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Objective: To determine incidence of hypercalcemia among TB patients with and without HIV infection before and after anti-TB chemotherapy in tropical settings of Northwest Ethiopia. Methods: Serum levels of calcium were determined using an inductively coupled plasma mass spectrometer from all subjects at baseline and from 60 TB patients (34 with HIV co-infection) at the end of an intensive phase of anti-TB chemotherapy. Results: At baseline, significant difference was found between the mean albumin-adjusted calcium levels in TB patients with HIV (11.95±3.72) and controls (9.81±1.59) (P=0.03). Hypercalcemia (serum calcium of &gt
10.5 mg/dL) was observed in 62.2% and 43.2% of TB patients with and without HIV co-infection, respectively. The serum levels of calcium did not significantly change after anti-TB chemotherapy both in patients with (n = 34) and without (n = 26) HIV co-infection. Conclusions: The present study suggests that TB itself appears not to be responsible for hypercalcemia
however, rates of hypercalcemia are high in TB and HIV co-infected patients in the tropical settings of Northwest Ethiopia, of rarely symptomatic. Anti-TB chemotherapy does not improve the incidence of hypercalcemia in both groups with HIV co-infection and without. © 2012 Asian Pacific Tropical Medicine Press.

DOI： 10.1016/S2222-1808(12)60234-5

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Language：Japanese   Publisher：徳島大学  

A visible colorimetric sensing device for determination of selenium(VI) is proposed. Thismethod is simply measuring the fluorinated coloration length of a microcolumn to determinationSe(IV). The extension of the length of color band was generated by accumulation of a fluorescencereactant (Se-DAN) between Se(VI) and diaminonaphtalene (DAN) on an adsorbent in a micorcolomn.Modification with β-cyclodextrin on octadecyl functional groups (C18)-modified beads as adsorbent ofSe-DAN enhanced the florescence. A detection limit of 30 μg L-1 for Se with a linear range up to 150μg L-1 was obtained. The determination scheme was successfully applied to the analysis of a sampleof tap water.

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DOI： 10.1142/S2010194512004047

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DOI： 10.1142/S2010194512003030

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Language：Chinese   Publishing type：Research paper (scientific journal)   Publisher：11  

In this study, a novel low cost magnetic adsorbent material prepared by poly-γ-glutamic acid(γ-PGA) coating Fe3O4 magnetic particles, which was called coated magnetic namoparticles(PG-M) was developed for the removal of Pb2+ from water by Dr. Yasuzawa. The particle size of PG-M was about 120-320 nm, and there was no significant difference in Fe3O4 and PG-M particle size, Fe3O4 was only as the support of PG-M core and did not directly involve in the reaction. The shape of PG-M was irregular cubic structure. The experiments were applied to quantify adsorptive time, pH, competitive ion and organics on the removal effect of Pb2+. The results showed that PG-M was effective in removal of Pb2+
the equilibrium amount of adsorptive was as high as 93.3 mg/g and the optimized condition of pH value for metal ions removal was 7.0, while contact time was about 45 min. The removal efficiency of Pb2+ was not significantly influenced by Na+ while was reduced with the increasing concentration of Ca2+. The removal of Pb2+ was enhanced with the presence of organic matter(humic acid, HA) when the concentration of HA was below 5 mg/L, and decreased when the concentration of HA exceeded 5 mg/L. Langmuir isotherms fitted the experimental data better compared to Freundlich isotherms. Pseudo second order model well described the sorption kinetics of Pb2+. The used PG-M can be desorbed by 0.1mol/L HCl and became reusable. PG-M is nontoxic and eco-friendly, which have a good prospect in water treatment.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC ANALYTICAL CHEMISTRY  

Fine needle-type glucose sensors with an outer diameter of less that 0.2 mm were fabricated using a low-cost biodegradable gamma-polyglutamic acid (PGA) not only as a glucose oxidase (GOx) immobilizing material, but also as a permselective inner membrane. PGA film was prepared on a cellulose acetate-coated Pt-lr wire electrode, and GOx was covalently immobilized on its surface using water-soluble carbodiimide. The obtained electrode was practically not affected by the existence of electroactive compounds, and provided long-term stability for approximately one month. It also functioned in horse serum with a good linear relationship between the current and glucose concentrations within the range of 2.8 to 22.4 mM.

DOI： 10.2116/analsci.27.337

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We identified a gene encoding a soluble quinoprotein glucose dehydrogenase homologue in the hyperthermophilic archaeon Pyrobaculum aerophilum. The gene was overexpressed in Escherichia coli, after which its product was purified and characterized. The enzyme was extremely thermostable, and the activity of the pyrroloquinoline quinone (PQQ)-bound holoenzyme was not lost after incubation at 100 degrees C for 10 min. The crystal structure of the enzyme was determined in both the apoform and as the PQQ-bound holoenzyme. The overall fold of the P. aerophilum enzyme showed significant similarity to that of soluble quinoprotein aldose sugar dehydrogenase (Asd) from E. coli. However, clear topological differences were observed in the two long loops around the PQQ-binding sites of the two enzymes. Structural comparison revealed that the hyperthermostability of the P. aerophilum enzyme is likely attributable to the presence of an extensive aromatic pair network located around a beta-sheet involving N- and C-terminal beta-strands. (C) 2010 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.abb.2010.08.002

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A simple and compact system was developed for the on-site analysis of lead in environmental water samples. The system consisted of a custom-made blue diode as a light source, a liquid core waveguide (LCW) as spectrophotometric cell and a compact UV-visible spectrometer. It weighed within 1.5 kg in total. Lead was detected using a spectrophotometric indicator reagent (TPPS: 5,10,15,20-tetraphenyl-21H,23H-porphinetetrasulfonic acid, disulfuric acid, tetrahydrate) after masking interfering ions by coprecipitation with magnesium hydroxide. With an increase in the length of the LCW cell, the detection limit of lead was almost linearly enhanced, and the linear calibration range was shifted to a lower concentration range. The detection limit of lead by using 100 cm of a LCW cell was 2 nmol dm(-3). The observed value (9.6 +/- 0.4 mu g dm(-3)) of lead in a river-water reference material (JSAC 0302-3) with this system was in good agreement with the certified value (9.9 +/- 0.2 mu g dm(-3)).

DOI： 10.2116/analsci.26.407

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Airborne particulate matter (PM) collected in Bucharest (Romania) and Tokushima (Japan) was comprehensively characterized through multielemental analysis by ICP-MS to the PM samples. Prior to an elemental characterization of the sample, a multielemental determination method composed of acid digestion (HClO(4)/HNO(3)/HF or H(2)O(2)/HNO(3)/HF) and inductively coupled plasma mass spectrometry/inductively coupled plasma atomic emission spectrometry (ICP-MS/ICP-AES) was established to analyze a certified reference material of vehicle exhaust matter (NIES No. 8) for verifying the method. As the results, 39 elements in the certified reference material could be determined. They were a good agreement with the certified and reference values for HClO(4)/HNO(3)/HF acid digestion. Chalcophile elements, such as cadmium, antimony, and lead in Bucharest showed higher enrichment factors than those in Tokushima.

DOI： 10.2116/analsci.26.395

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Language：English   Publisher：日本海水学会  

A method for collecting metal ions with colloidal Mg hydroxide by means of ultrafiltration was developed. One mg dm<sup>–3</sup> of Mg concentration was sufficient to recover analytes in the sample. The recoveries of trace elements did not depend on the aging time. When trace elements in riverine water reference material SLRS-4 were analyzed using this preconcentration method with inductively coupled plasma mass spectrometry (ICP-MS) measurements, the obtained values for Al, Mn, Fe, Co, Ni, Cd, and rare earth elements agreed well with the certified or literature values. The performance of this method was sufficient for the determination of trace elements in Yoshinogawa-river sample without addition of any outside coprecipitant.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC ANALYTICAL CHEMISTRY  

Carbon nanotube (CNT)gel, which is composed of a mixture of single-wall CNT, ail ionic liquid, thermostable D-proline dehydrogenase (D-Pro DH) immobilized electrode was utilized for the determination of D-amino acids (DAAs) in food samples. When a critical comparison with CNT, Ketjen Black (KB), and carbon powder (CP) was also carried Out, the CNT/D-Pro DH immobilized electrode showed the highest sensitivity and the lowest detection limit of D-proline. In addition, the CNT/D-Pro DH immobilized electrode was applied to detection of DAAs in rice wine and vinegar samples. The concentrations of DAAs in rice wine and vinegar samples were 0.0210 +/- 0.0001 and 0.55 +/- 0.05 mmol L(-1). respectively.

DOI： 10.2116/analsci.25.919

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE INC  

Objective: We investigated the prevalence of anemia and deficiency in trace elements in adolescent girls living in rural Vietnam.
Methods: Two hundred forty-five adolescent girls 11-17 y of age from three schools in rural province of Ha Nam, Vietnam, were assessed.
Results: The prevalence of anemia was 20.4%. The incidences of low serum selenium (Se), zinc, and copper in subjects were 15.9%, 26.5%, and 4.1%, respectively. The parameter significantly associated with anemia was the low serum levels of Se and vice versa (odds ratio [OR] 5.36, 95% confidence interval [CI] 2.57-11.18, P < 0.0001). Other risk factors for anemia were a body mass index < 17.00 kg/m(2) (OR 2.72, 95% CI 1.37-5.37, P = 0.004) and years of age (OR 1.35, 95% CI 1.14-1.59, P < 0.001). A body mass index <17.00 kg/m(2) (OR 2.65, 95% CI 1.25-5.61, P = 0.011) was also found to be a risk factor for low serum Se.
Conclusion: The findings of the present study demonstrate that low serum Se is independently associated with anemia in adolescent girls living in rural Vietnam. Interventions are required to gain insight into the potential role of Se on prevention and control of anemia. (C) 2009 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.nut.2008.06.032

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CENTER ACADEMIC PUBL JAPAN  

A cross-sectional study of 292 primary school children was conducted in rural Vietnam to investigate the relationship among micronutrient deficiencies, and other risk factors for anemia. Serum levels of iron, copper. zinc, selenium and magnesium were determined by inductively coupled plasma mass spectrometry and that of retinol by high performance liquid chromatography. Hemoglobin concentration in whole blood was measured by the cyanmethemoglobin method. The incidence of low serum zinc, selenium, magnesium, and copper in the children was 97..4, 75.6, 59.5, and 8.6`0, respectively. Forty-five percent of the children were anemic and 11.3% suffered from vitamin A deficiency. A parameter significant associated with anemia was low serum selenium and vice versa (OR 1.85. 95% CI 1..06-3.24, p < 0.05). Other factors associated with anemia were serum retinol < 1.05 mu mol/L (OR 2.05, 95% CI 1.25-3.36, p < 0.01.), and age in years (OR 1.59, 95% CI 1.16-2.18, p < 0.01). The study showed that low selenium is associated with anemia among school children in Vietnam. Interventions are required to gain insight into the potential role of selenium on prevention and control of anemia.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

A novel biosensor for determination of D-amino acids (DAAs) in biological samples by using an electrode based on immobilization of a thermostable D-Proline dehydrogenase (D-Pro DH) within an agar gel membrane was developed. The electrode was simply prepared by spin-coating the agar solution with the D-Pro DH on a glassy carbon (GC) electrode. An electrocatalytic oxidation current of 2,6-dichloroindophenol (DCIP) was observed at -100 mV vs. Ag/AgCl with the addition of 5 and 20 mmol L-1 D-proline. The current response and its relative standard deviation were 0.15 mu A and 7.6% (n = 3), respectively, when it was measured in a pH 8.0 phosphate buffer solution containing 10 mmol L-1 D-proline and 0.5 mmol L-1 DCIP at 50 degrees C. The current response of D-proline increased with increase of the temperature of the sample solution up to 70 degrees C. The electrocatalytic response at the D-Pro DH/agar immobilized electrode subsequently maintained for 80 days. Finally, the D-Pro DH/agar immobilized electrode was applied to determination of DAAs in a human urine sample. The determined value of DAAs in the human urine and its R.S.D. were 1.39 +/- 0.12 mmol L-1 and 8.9% (n = 3), respectively. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.aca.2008.04.063

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Language：Japanese   Publisher：徳島大学  

Selenium(IV) and Se(VI) were visually detected and determined based on fluorometricderivatization used by 2,3-diaminonaphtalene (DAN) and β-cyclodextrin (β-CD) / sodiumdodecyl sulfate (SDS) as fluorometric enhancer. The visual determination of Se was achieved byremoving non-reacted DAN, which causes severe interferences and shows high background forvisual determination, with a cation exchange treatment. The cation exchange treatment providedover 90% of its removal efficiency without loss of Se-DAN. In order to determine Se(VI), Se(VI)was converted to Se(IV) based on the reduction of the treatment under 6 mol l-1 HCl at 110 °C.Se(IV) and Se(VI) in a river water and a seawater sample could be quantitively recovered throughthe Se-DAN derivatization and the cation exchange treatment. Under the optimal condition forvisual determination of Se, the fluorometric color was visually detected from 20 μg l-1 to 5000 μg l-1of Se(IV) and from 100 μg l-1 to 5000 μg l-1 of Se(VI) and the difference of the color every 20-50 μgl-1 was distinguished.

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J-GLOBAL

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Language：Japanese   Publisher：一般社団法人電子情報通信学会  

A D-amino acids sensor based on therrmostable D-Proline dehydrogenase(D-Pro DH) immobilized with thermoreversible agar gel was prepared. Influence of polar organic solvents on the properties of the D-Pro DH immobilized electrode was investigated by electrochemical techniques. Under the aqueous solution, the current response of D-Proline increase of the temperature of the solution up to 50℃. As a result of the long term stability, the response was stable for 80 days. The current response of D-Proline decreased with increase the mixing ratio of alcohols. The current response was correlated with the dielectric constant of alcohol solvents.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC ANALYTICAL CHEMISTRY  

A glucose sensor was developed by electrocopolymerization using pyrroles containing a tris-bipyridine (bpy) osmium complex (Os-py), pyrrole (py), pyrrole propanoic acid (PPA) and glucose oxidase (GOx) to improve the key performance characteristics, such as the sensitivity, selectivity, and long-term stability. Tris-bipyridine osmium pyrrole complexes with four different methylene moieties were utilized to correlate the methylene length with the glucose sensor performance. The electrocatalytic response of glucose was clearly observed at electrodes modified with Os-py, except for the electrode immobilized with the Os-py complex containing the shortest methylene moiety. The current response to glucose increased up to a concentration of 100 mmol dm(-3). The electrocatalytic response to glucose at the [Os(bpy)(2)(py(6)-bpy)](2+/3+)/py/PPA/GOx electrode was stable for more than 100 days. Dissolved oxygen and potential interference compounds (ascorbic acid, uric acid, and acetaminophen) minimally perturbed the current response to glucose at the [Os(DM-bpy)(2)(py(6)-bpy)](2+/3+)/py/PPA/GOx electrode. Based on these results, a longer methylene moiety appears to improve the performance characteristics of a glucose sensor fabricated via the electropolymerization of trisbipyridine osmium pyrrole complexes.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC ANALYTICAL CHEMISTRY  

We present a new multielement masking method using magnesium hydroxide coprecipitation for the selective determination of Pb by differential pulse anodic stripping voltammetry (DPASV). The recovery of Pb in the masking method was over 95%, while interfering ions (Cd2+, CO2+, Cu2+, Fe3+, Mn2+, and Ni2+) could be removed at 100% from the analytical sample. A linear regression was obtained in the Pb concentration from 10 to 1000 mu g kg(-1) in the existence of 100 mu g kg(-1) of the interfering ions. When this method was applied to the determination of Pb in a natural water-standard reference material (NIST 1640), the determined value for Pb in this work (25.4 +/- 4.1 mu g kg(-1)) almost agreed with the certified value (27.89 +/- 0.14 mu g kg(-1)).

DOI： 10.2116/analsci.22.1021

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

The concentrations of major-to-ultratrace elements in bittern, which was obtained after seawater concentration in the salt preparation process, were investigated by ICP-AES (inductively coupled plasma atomic emission spectrometry) and ICP-MS (inductively coupled plasma mass spectrometry) with and without the aid of chelating resin preconcentration. As a result, 34 elements in bittern could be determined in the concentration range from 10(7) to 10(-3) ng mL(-1) with good RSDs (less than 5%) for most analyte elements. Based on the experimental results, the concentrations of the elements in bittern were compared with those in seawater. Furthermore, the distribution factors of major-to-ultratrace elements in bittern were estimated to elucidate the partitionings of those elements among the calcium precipitate, the salt and the bittern from coastal seawater. The results suggest that the concentrations of the elements in bittern significantly depended on their chemical forms in seawater. For example, K and Mg in ionic form, V, Mo, W, and U in oxoanion form, and Cu and Zn in complex form with organic molecules in seawater, were much more partitioned in bittern than in salt.

DOI： 10.1246/bcsj.79.588

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

The concentrations of major-to-ultratrace elements in bittern, which was obtained after seawater concentration in the salt preparation process, were investigated by ICP-AES (inductively coupled plasma atomic emission spectrometry) and ICP-MS (inductively coupled plasma mass spectrometry) with and without the aid of chelating resin preconcentration. As a result, 34 elements in bittern could be determined in the concentration range from 10(7) to 10(-3) ng mL(-1) with good RSDs (less than 5%) for most analyte elements. Based on the experimental results, the concentrations of the elements in bittern were compared with those in seawater. Furthermore, the distribution factors of major-to-ultratrace elements in bittern were estimated to elucidate the partitionings of those elements among the calcium precipitate, the salt and the bittern from coastal seawater. The results suggest that the concentrations of the elements in bittern significantly depended on their chemical forms in seawater. For example, K and Mg in ionic form, V, Mo, W, and U in oxoanion form, and Cu and Zn in complex form with organic molecules in seawater, were much more partitioned in bittern than in salt.

DOI： 10.1246/bcsj.79.588

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Language：Japanese   Publisher：海水誌  

Trace elements in seawater have attracted a great deal of attention from the viewpoint of bio-resources, local environmental pollution and global material cycles.Many researchers have been trying to develop efficient analytical methods for determination of trace elements in seawater and common salts.<BR>Multielement analysis for trace elements has high potential to obtain a large variety of information for an analytical sample.This review introduces recent progresses for multielement determination methods of trace elements in seawater and common salts.

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A multielement determination method for trace elements in scallop tissue samples has been developed by ICP-MS (inductively coupled plasma mass spectrometry) and ICP-AES (inductively coupled plasma atomic emission spectrometry) after microwave assisted acid digestion. A reference material of oyster tissue (SRM 1566b Oyster tissue) was analysed to verify the determination method. Thirty elements (K, Na, Zn, Mg, Ca, Fe, Al, Cu, Mn, Ba, Sr, Cd, Ni, Co, Pb, Y, and rare earth elements) in the reference material could be determined, and the concentrations of elements obtained by this method were in good agreement with their certified and reference values and had good precision within RSD 4% except for Ni and Pb. This method was applied to analyse concentrations of elements in a scallop tissue sample. Cadmium, Zn, Cu, Al, and Fe in the scallop tissue sample were contained at 69.0, 148, 19.0, 415, and 221 mg g-1 level, respectively. In particular, the bioaccumulation factors of Cd, which were estimated between the concentration in scallop tissue sample and those in shale and seawater, were the highest among 30 elements determined.

DOI： 10.2116/bunsekikagaku.53.1435

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DOI： 10.11457/swsj1965.58.36

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WORLD SCIENTIFIC PUBL CO PTE LTD  

The electrochemical behavior of an enzyme sensor for glucose using a gold electrode modified with thiol self-assembled membrane and osmium complex gel as an electron transferring mediator has further been investigated by electrochemical analysis. The gold electrode was initially coated with aminomethanethiol self assembling mono layer membrane(thiol-SAM) and then immobilized with glucose oxidase using poly(vinylpyridine-co-allylaniine) (PVP-co-AA), gel coordinated with osmium bipyridine complexes (GOD/Os-PVP-co-AA gel). The cleaning condition of the surface of the Au electrode prior to coating thiol SAM was optimized for reduction of interference caused by concomitant compounds. It was found that interfering influence was most efficiently reduced in the case of use of the Au electrode immersed into nitric acid. The current ratio with a thiol coated gold electrode modified with Os-PVP-co-AA gel in glucose solution in the presence to absence of ascorbic acid, acetaininophen, and uric acid (ID+I/I-I) was 1.006, 1.014, and 1.018, respectively. The peak current response of glucose in the electrode modified with thiol SAM was dropped to 60 - 98 % as compared with that without thiol SAM.

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC ANALYTICAL CHEMISTRY  

A novel glucose sensor base on an osmium-complex modified polypyrrole was prepared and evaluated. Four new-type osmium-complexes ([Os(bpy)(2)(py(4)-bpy)](2+/3+), [Os(bpy)(2)(py(3)-bpy)](2+/3+), [Os(bpy)(2)(pyro-pri)Cl] (+/2+), and [Os(bpy)(2)(Vi-bpy)] (2+/3+)) were synthesized, and the kinetic parameters analyzed. A hydrophilic redox polymer with an osmium-complex was modified by electrolytic copolymerization on the surface of a platinum electrode. The effects of the polymer concentration, times of the scan, dissolved oxygen, and concomitant compounds, and a calibration curve for measurements of glucose were analyzed. The catalytic currents of synthesized osmium-complexes were observed. The relationship between glucose and the oxidation current was examined using the sensor under the optimum conditions. A linear relationship was obtained over the range of 0.9 similar to 100 mmol dm(-3) glucose. It was measured in the presence of ascorbic acid or uric acid. These compounds did not affect the response current. The life-time of the sensor was also examined. The analytical values were constant for 9 days when the sensor was stored in a pH 7.07 phosphate buffer solution at 4 degreesC.

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Language：English   Publisher：社団法人 日本分析化学会  

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC ANALYTICAL CHEMISTRY  

Multielement monitoring of the concentrations of trace metals dissolved in surface seawater collected at sampling stations along the ferry track between Osaka and Okinawa was performed by ICP-MS (inductively coupled plasma mass spectrometry). The surface seawater samples were collected by an automated sampling system for on-board sampling, which was installed on the bottom of a ferryboat. A part of each seawater sample was filtered with a membrane filter (pore size of 0.45 mum) immediately after sampling. Both filtered and non-filtered seawater samples were acidified to pH ca. 1 by adding cone. HNO3, and were subjected to chelating resin preconcentration for the determination of trace metals by ICP-MS, where the concentrations of analyte metals in the filtered and non-filtered seawater samples were referred to as the dissolved and total concentrations, respectively. According to the thus-obtained results, it was found that most trace metals, especially below the 0.01 mug 1(-1) as the dissolved and total concentrations, sensitively reflected the environmental pollution in the Osaka Bay and Seto Inland Sea area. as well as near to the Bungo Canal and the outlet of Kagoshima Bay.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

A tandem preconcentration method, in which chelating resin adsorption and La coprecipitation were cooperatively employed for preconcentration, was developed as a pretreatment method for simultaneous multielement determination of trace elements in seawater by ICP-MS. First, the seawater sample (250 ml) was treated with a chelating resin for preconcentration of trace elements, and then trace elements with good recoveries were determined by ICP-MS. Trace elements with the chemical properties of oxoanion- and hydride-formation, which were poorly recovered in the chelating resin preconcentration, were further subjected to preconcentration by La coprecipitation. As a result, more than 30 elements could be determined in the concentration range from 9.6 mug L-1 for Mo to 0.00018 mug L-1 for Tm, when the present tandem method was applied to the analysis of open seawater standard reference material (NASS-4). Furthermore, the analytical results for open seawater reference materials were compared with those for coastal seawater reference material as well as for coastal seawater collected in the Ise Bay. It was found that the multielement data for trace elements in these seawater samples clearly showed different elemental distributions, reflecting the different marine environments.

DOI： 10.1246/bcsj.74.31

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Language：Japanese   Publisher：社団法人 環境科学会  

An analytical method for multielement determination of tarce elements in natural water (terrestrial water and seawater) by ICP-AES (inductively coupled plasmaatomic emission spectrometry) and ICP-MS (inductively coupled plasma massspectrometry) has been explored with the aid of chelating resin preconcentration, using Chelex-100 resin from Bio-Rad Laboratories (USA) . In order to evaluate the analytical reliability, the present chelating resin preconcentration/ analytical plasma spectrometry (ICP-AES and ICP-MS) method was applied to the determination of trace elements in river water certified reference material issued from the Japan Society for Analytical Chemistry and coastal seawater certified reference materialissued from National Research Council of Canada. The present method was alsoapplied to the analyses of Lake Biwa and Kagamiga-ike pond water samples. Furthermore, chemical speciation of trace elements in natural water by a combined system of SEC (size exclusion chromatography) / UV absorption/ ICP-MS (or ICP-AES) wasperformed after ultrafiltration preconcentration to elucidate the dissolved states or species of such trace elements. In ultrafiltration preconcentration, an ultrafiltrationfilter with the molecular permeation limit of 10, 000 Da in molecular weight (MW) wasused. As a result, it has been elucidated that most of trace elements exist as the largeorganic molecule-metal complexes (LOMMCs) in natual water. Such LOMMCs areobserved at Peak 1 (MW > 300, 000 Da) and Peak 2 (MW 10, 000-50, 000 Da) on the SEC chromatogram detected by ICP-MS. The fractional distributions of trace elements in the small-molecule, large-molecule and particle fractions of seawater werealso evaluated from the determination of trace elements in membrane (pore size 0.45, um) -filtered seawater, ultrafiltration (molecular permeation limit 10, 000 Da) -filteredseawater and particles remained on the membrane filter. In consequence, it wasconfirmed that LOMMCs of trace metals exist even in seawater. From these experimentalresults, a string-ball model is proposed as the dissolved species in naturalwater. The string-ball model is a formation model of LOMMCs with MW larger than 300, 000 Da, corresponding to Peak 1 in the SEC chromatogram, in which LOMMCs arecomposed of hydroxide colloides of Al and Fe as the cores and biogenic organicmaterials and diverse inorganic metal ions as the adsorbents on the cores, and such LOMMCs may grow their sizes to form the suspended particles in natural water. Onthe other hand, LOMMCs corresponding to Peak 2 in the SEC chromatogram may bemetal complexes of trace elements with biogenic protein-like compounds.

DOI： 10.11353/sesj1988.13.313

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC ANALYTICAL CHEMISTRY  

DOI： 10.2116/analsci.16.675

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC ANALYTICAL CHEMISTRY  

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Language：English   Publisher：Chemical Society of Japan  

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Language：Japanese   Publisher：海水誌  

Major-to-ultratrace elements in common salts were determined by ICP-AES (inductively coupled plasma atomic emission spectrometry) and ICP-MS (inductively coupled plasma mass spectrometry). The salt samples (Fukken salt, Noto salt, Akoh salt, Seto salt, JT salt) were dissolved in pure water, and the salt water solutions were filtered with a membrane filter (pore size 0.45μm). The filtrates and the particulates remained on the filter for each salt sample were analysed as the water-soluble and particulate constituents of salts, respectively. Although the portion of particulates in natural salts was ca. 0.006-0.06%, the concentrations of Al, Ti, Fe, Zn, Ga, Y, rare earth elements, and Th in particulate constituents were more than 80% of their total concentrations in salt. Sodium, K, Mg, Ca and Sr were mostly in water-soluble forms. In addition, more than 80% of Mo and Cd were also in water-soluble forms for all salts examined here, reflecting their chemical forms in sea water.

DOI： 10.11457/swsj1965.54.117

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

The simultaneous multielement determination of trace elements in seawater, especially hydride- and oxoanionforming elements, has been investigated by inductively coupled plasma mass spectrometry with the aid of lanthanum coprecipitation preconcentration. The optimum pH in lanthanum coprecipitation was pH 9.5; at this value, trace elements were well recovered and major constituents of seawater such as Na, Mg, K, and Ca were significantly reduced in the concentrated solutions. The recovery values obtained for V, Cr(III), Mn, As(III), As(V), Se(IV), Y, Sn, Sb(III), Sb(V), W,Bi, and U were more than 85% after lanthanum coprecipitation, while Cr(VI), Se(VI), and Mo(VI) provided poor recoveries of less than 30%. The reproducibility for coprecipitation was within 5% as relative standard deviation. The present method was applied to the determination of trace elements in coastal seawater reference material CASS-3. The analytical values for Mn, As, V, Y,Sb, W, and U were in fairly good agreement with the certified or literature values.

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society for Analytical Chemistry  

The distributions of major-to-uhratrace elements into natural sale from coastal seawater in a salt-preparation process were investigated by ICP-AES (inductively coupled plasma atomic emission spectrometry) and ICP-MS (inductively coupled plasma mass spectrometry) with preconcentration using a chelating resin. The coastal seawater samples were collected off-shore near to the Nie coast, where Agehama-made salt is produced by a classical Ageharna method. Natural salt was produced from original coastal seawater in the laboratory in a similar manner to the Agehama method. First, the seawater samples were filtered with a membrane filter (pore size of 0.45 μm), and the elements in the dissolved fraction (filtrate) and in the participate fraction (particulate on the filter) were determined by ICP-AES and ICP-MS. The analytical results for seawater indicate that alkali elements, alkaline earth elements, and oxoanion-forming elements (V, Mo, W, U) were dominantly in the dissolved fraction, while other elements such as Al, Fe, Pb and rare earth elements were mostly in the particulate fraction. The elements in laboratorymade salt and Agehama-made salt were also determined by ICP-AES and ICP-MS after dissolving them in a 0.1 M HNO3 solution. Although the concentrations of trace elements in laboratorymade salt and Agehama-made salt were almost at the same levels for 27 elements among 34 elements within a factor between ca.1/5 and 5, Ba, Mn, Cd and Pb in Agehama-made salt were much higher (8-30 fold) in concentration than those in the laboratory-made salt. Based on the experimental results mentioned above, the distributions of major-to-ultralrace elements into natural salt from seawater were discussed, taking into consideration the preparation process of natural salt.

DOI： 10.2116/bunsekikagaku.49.111

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society for Analytical Chemistry  

The multielement determination of major-to-trace elements in insoluble particulates of solar salt was carried out by ICP-AES and ICP-MS. A solar salt sample (30 g) was dissolved in 11 of pure water to adjust its solution salinity to be almost the same as that of seawater. When the solar salt sample solution was filtered using a membrane filter (pore size 0.45 μm), the residue on the filter was defined as the insoluble particulates and the filtrate as the soluble constituents. The insoluble particulates were decomposed together with the membrane filter by an acid digestion method using HNO3, HF, and HClO4. As a result, 36 elements in the insoluble particulates could be determined at % to sub-μg g-1 levels by ICP-AES and ICP-MS. Taking into consideration the present results along with the analytical results for the soluble constituents reported in a previous paper, alkali elements, alkaline earth elements, Mo and Cd were found mainly in the soluble constituents of solar salt, while Al, Ti, V, Fe, Co, Ga, Y, Sn, and rare-earth elements (REEs) were found in the insoluble particulates. Iron, Co, Y, Sn, and REEs in the insoluble particulates were partly leached into the acid solution when the solar salt sample was dissolved in a 0.1 M HNO3 solution. Thus, it is considered that these elements are dissolved as colloidal matter adsorbed on particulates in seawater. On the other hand, because Mn, Cu, Zn, and Pb were found in both the insoluble particulates and the soluble constituents, these elements in the insoluble particulates were easily leached in a 0.1 M HNO3 solution. These results indicate that Mn, Cu, Zn, and Pb are contained as acid-soluble forms in the insoluble particulates. Moreover, the relative abundances of the elements normalized to the Al concentrations in the insoluble particulates of solar salt and the marine sediment standard material (NIES No. 12) showed a good linear correlation, which suggests that the insoluble particulates in solar salt are an origin of marine sediment.

DOI： 10.2116/bunsekikagaku.48.897

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society for Analytical Chemistry  

The multielement determination of trace elements in river water certified reference materials (JAC 0031 and JAC 0032), issued from the Japan Society for Analytical Chemistry, has been carried out by ICP-MS and ICP-AES. The chelating resin preconcentration method, using Chelex® 100, was employed for the enrichment of most trace elements, including rare-earth elements, while some of the elements were determined by direct sample introduction without any pretreatment. As a result, the concentrations of 37 elements in river-water certified reference materials were obtained in the present experiments. Their concentrations ranged from 1.23 × 10-3 g 1-1 for Ca to 1.2 × 10-12 g 1-1 for Tm. The analytical values for Ca, Na, Mg, K, Al, B, Fe, Cu, Zn, and Mn were almost in good agreement with the certified values, while that for Cr was not because of poor recovery in preconcentration. In addition, the REE (rare earth elements) distribution pattern of JAC 0031, normalized by the REE concentrations of continental shale, was compared with those of the Lake Biwa surface water and samples from 24 rivers in Japan.

DOI： 10.2116/bunsekikagaku.47.109

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Background: Selenium deficiency is known to be a major public health problem, associated with increased risk of mortality with AIDS and AIDS-related complex, diarrhea included compared to those of healthy controls. In Ethiopia, there are no studies conducted on serum selenium status diarrheic patients with and without HIV infection. Therefore, the present study was aimed at determining the level of serum selenium in HIV infected and sex and aged matched HIV negative diarrheic patients. Methods: This was a cross-sectional study of 206 (97 HIV seronegative and 109 HIV seropositive) diarrheic patients of both genders seen at University of Gondar Hospital, Gondar, Ethiopia. Serum selenium was measured by inductively coupled plasma-mass spectrometer. Results: The mean and standard deviation of serum selenium levels in HIV seropositives was 5.90 ± 2.78 μg/dl and in HIV seronegatives was 6.99 ± 4.26 μg/dl. Deficiency of selenium was seen in 95.9% and 71.56% of diarrheic patients with and without HIV co-infection, respectively. The over all selenium deficiency was observed in 83.0% of patients included in the study irrespective of their HIV serostatus while 85.3%of the patients infected with HIV and 80.4% of patients without HIV infection had serum selenium level below 7μg/dl. The low serum selenium level was not associated with presence or absence of intestinal parasites neither with sociodemographic variables such as age, residence, marital status, occupation, monthly income. The mean serum selenium level of all male cases was statistically significantly lower than that of the females (P&lt
0.05). Conclusion: Our results show high prevalence of selenium deficiencies in HIV seropositive and seronegative diarrheic patients in Gondar, Ethiopia. Although this is a small group of study subjects, the findings may be used as a tool to suggest further in-depth prospective clinical trials to determine whether selenium supplements may be of public health benefit among HIV-infected populations as a stand-alone therapeutic approach and potentially as an adjuvant to antiretroviral therapy. © 2011 Amare, et al.

DOI： 10.4172/2155-6113.1000128

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Language：Japanese   Publisher：公益社団法人 日本分析化学会  

For the development of a sensitive and accurate immunosensor, the production of a highly specific surface to the corresponding antibody is essential. Moreover, a specific surface having good reusability is worthwhile for constructing a prompt auto-monitoring immunosensing system. In this study, antigen analogous-modified gold substrates having a specific adsorption property to an anti-dioxin antibody, were prepared by the immobilization of 2,4,5-trichlorophenoxy (TCP) derivatives on a gold surface using various methods. An anti-dioxin antibody, which has a good correlation immunoaffinity with the total toxic equivalent quantity (TEQ) of polychlorinated dibenzo-p-dioxins, was employed as a specific antibody, and the specification of the surface was evaluated by a comparison of the surface plasmon resonance (SPR) responses to a specific anti-dioxin antibody and non-specific anti-hemoglobin antibody. In order to obtain a firm and stable immobilization of TCP, a carboxyl group was introduced on gold by a self-assemble monolayer (SAM) technique, and TCP derivatives were attached to the SAM surface with covalent bonding directly and indirectly through the presence of a hexamethylene chain, bovine serum albumin (BSA), and ethylene glycol oligomer (EGO). A TCP derivative-immobilized substrate, prepared using BSA, showed poor reusability. A TCP derivative-immobilized substrate having EGO was highly specific to an anti-dioxin antibody, while that prepared by the direct immobilization of TCP and with introduction of a hexamethylene chain presented nonspecific adsorption. In addition, a TCP derivative-immobilized substrate having EGO showed a good reproducible response from the second repetition, and was reusable more than seven times. © 2011 The Japan Society for Analytical Chemistry.

DOI： 10.2116/bunsekikagaku.60.81

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Language：Japanese   Publishing type：Rapid communication, short report, research note, etc. (scientific journal)   Publisher：公益社団法人 日本分析化学会  

A flow-injection amperometric analysis system for the determination of glucose in human urine was analyzed. The glucose sample was mixed with glucose oxidase, and was introduced into the flow-injection system. Hydrogen peroxide produced by an enzymatic reaction was amperometrically detected by a platinum electrode modified with Nafion, and an electrochemically polymerized saccharide substituted polypyrrole. The influence of electroactive compounds such as ascorbic acid, uric acid, and acetaminophen to the glucose response observed in this system was negligible. A good linear relationship between the glucose concentration and the response current was obtained within a concentration of up to 22.4 mmol dm-3. The relative standard deviation for ten replicate analyses of 5.6 mmol dm-3 glucose in human urine was 7.4%. © 2009 The Japan Society for Analytical Chemistry.

DOI： 10.2116/bunsekikagaku.58.941

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Authorship：Lead author,　Corresponding author   Language：English   Publisher：社団法人 日本分析化学会  

Both 206Pb-labeled trimethyllead (TML) and triethyllead (TEL) were synthesized from 206Pb-enriched metallic Pb certified reference material (NIST SRM 983) and iodomethane or iodoethane through a one-process reaction in a closed system using centrifuge tubes, respectively. Organolead compounds in an urban dust reference material (BCR CRM 605) were extracted with an acetic acid/methanol (1:1) solution, which was mechanically shaken for 24 h. After adjusting the pH of the extracted solution to pH 5, the extracted organolead compounds were derivatized by tetrabutylammonium tetrabutylborate (TATB) and measured with GC-ICPMS. The analytical results of TML and TEL for BCR CRM 605 were 8.22 ± 0.04 mg kg-1 (mean ± standard deviation, n = 3) and 1.12 ± 0.06 mg kg-1, respectively. The analytical results of TML agreed well with the certified value (7.9 ± 1.2 mg kg-1). 2008 © The Japan Society for Analytical Chemistry.

DOI： 10.2116/analsci.24.791

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Language：English   Publisher：HUMANA PRESS INC  

Pregnant women in developing countries are vulnerable to multiple micronutrient deficiencies. Studies assessing serum levels of the micronutrients and magnitude of their deficiencies are very scarce in African subjects. This study was aimed at determining serum levels of micronutrients in 375 pregnant (42 HIV seropositive) and 76 non-pregnant women (20 HIV seropositive) who visited the University of Gondar Hospital, Gondar, Ethiopia. Serum concentrations of zinc,\ copper, selenium, calcium, and magnesium were determined using an inductively coupled plasma mass spectrometer. Irrespective of HIV serostatus, pregnant women had significantly higher serum concentrations of copper and copper/zinc ratio and significantly lower magnesium compared to those in non-pregnant women (P<0.05). Except for selenium, which was significantly lower in HIV-seropositive pregnant women (P<0.05), the mean serum concentrations of zinc, copper, calcium, and magnesium were not significantly different between pregnant women by HIV serostatus. The prevalence of deficiency in zinc, magnesium, selenium, and calcium in the pregnant women, irrespective of their HIV serostatus, was 66.7%, 25.6%, 21.9%, and 9.3%, respectively. The magnitude of deficiency in zinc, magnesium, and selenium was significantly higher in HIV seropositive pregnant women (76.2%, 52.4%, and 45.2%) than that in HIV-seronegative pregnant women (65.5%, 22.2%, and 18.9%) and in HIV-seronegative non-pregnant women (42.9%, 8.1%, and 30.4%; P<0.05). Deficiency in one, two, three, or four mineral elements was observed in 44.8%, 14.4%, 9.9%, and 5.1% of the pregnant women, respectively. Only 25.9% of the pregnant women and 44.7% of the nonpregnant women were not deficient in any of the micronutrients. The high prevalence of micronutrient deficiencies in pregnant and non-pregnant women in Gondar, Ethiopia warrants the need for strategies on prevention and control of the deficiencies.

DOI： 10.1007/s12011-007-8067-6

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Language：English   Publisher：H E C PRESS, HEALTHY EATING CLUB PTY LTD  

The prevalence of trace elements deficiencies, vitamin A deficiency, anemia, and their relationships were investigated in a cross sectional study involving 243 children aged from 12 to 72 months in rural Vietnam. Serum levels of copper, zinc, selenium and magnesium were determined by inductively coupled plasma mass spectrometer and that of retinol by high performance liquid chromatography. Hemoglobin concentration in whole blood was measured by the cyanmethemoglobin method. The prevalence of deficiencies in zinc, selenium, magnesium, and copper was 86.9%, 62.3%, 51.9%, and 1.7%, respectively. On the other hand, 55.6% were anemic and 11.3% had vitamin A deficiency. Deficiency in two or more micronutrient was found in 79.4% of the children. Parameters associated significantly with anemia were selenium deficiency (OR 2.80 95% CI 1.63-4.80, p = 0.0002) and serum retinol <1.05 mu mol/L (OR 1.83, 95% CI 1.10-3.05, p = 0.021). Magnesium deficiency (OR 3.09 95% CI 1.36-7.03) was found to be a risk factor for zinc deficiency and vice versa. The results indicate that micronutrient deficiencies are prevalent among preschool children in Vietnam. In addition, the results also demonstrate a strong relationship between selenium deficiency and anemia. Clearly, sustainable strategies are urgently required to overcome the problems in the country.

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Authorship：Corresponding author   Language：Japanese   Publisher：公益社団法人 日本分析化学会  

A multielemental determination method for major-to-trace elements in sewage sludge has been developed by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma atomic emission spectrometry (ICP-AES) after microwave radiation assisted acid digestion or alkali fusion. A reference material of sewage sludge (BCR-144R) was analyzed to verify the determination method. The determined values of some elements such as Zn, Cu, Pb, Ni, Co and Cd by the alkali fusion were lower than the certified values. The analytical values of Cu and Ni obtained by the alkali fusion method with a platinum crucible was lower than those with a pyrolysis boron nitride crucible. From these results, it was suggested that the losses in the alkali fusion were due to volatilization among ignition for Zn, Pb, Co and Cd and alloy formation between Cu and Ni and platinum as crucible material. Furthermore, hydrofluoric acid was necessary to dissolve niobium, tantalum and hafnium in both decomposition processes for acid digestion and alkali fusion. The microwave radiation assisted acid digestion/ICP-MS and ICPAES method was applied to the determination of major-to-trace elements in a sewage sludge sample collected at a sewage treatment plant in Tokushima. As a result, 44 elements could be determined. © 2008 The Japan Society for Analytical Chemistry.

DOI： 10.2116/bunsekikagaku.57.659

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Language：English   Publisher：WORLD SCIENTIFIC PUBL CO PTE LTD  

Ionic liquids are expected to replace conventional organic solvents in organic synthesis, solvent extraction and electrochemistry due to their unique characters such as low volatility, high stability and so on. In this work, N,N,-diethyl-N-methyl-N-(2-methoxyethyl) ammonium bis(trifluoromethansulfonyl)iniide was used as an alternative solvent to extract heavy metal ions. As the extracting conditions, the additional effect of 8-hydroxyquinoline (8-HQ) as metal chelating agent into ionic liquids, shaking time and volume ratio were investigated. As extraction efficiency depended on 8-HQ concentration significantly, in order to extract high concentrated metal ions the solubility of 8-HQ into ionic liquid was tested. N,N,-diethyl-N-methyl-N-(2-methoxyethyl) ammonium bis(trifluoromethansulfonyl)imide had good solubility of 8-HQ. Consequently, 5 mu mol of copper, zinc, cadmium and manganese could be completely recovered with 100 mu l of ionic liquid.

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Language：English   Publisher：WORLD SCIENTIFIC PUBL CO PTE LTD  

A porous micro-electrode with immobilized poly(methacryroyl alanine) (PMA) was developed for measuring copper(II) ion (Cu2+) and cadmium(II) ion(Cd2+). A porous carbon material was packed into the tip of the platinum micro-electrode with a cavity at the top. The porous micro-electrode was dipped in the coating dimethyl sulfoxide solution with PMA and di-2-ethylhexyl phthalate and dried overnight at room temperature. The immobilized PMA on the porous micro-electrode had predominantly a keto form in the buffer solution. In the enol form a metal complex can be formed under the simultaneous liberation of a proton. Calibration curves for measurements of Cu2+ and Cd2+, the effects of preconcentration condition, scan rate, pH, and temperature, and lifetime of the PMA modified micro-electrode were examined. Under optimal conditions, the responses of sensor were linear in the concentration range 0.0001-1 mmol l(-1) for Cu2+ and 0.01-1 mmol l(-1) for Cd2+. Analytical values determined with the modified electrode were constant for at least 3 month.

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Language：English   Publisher：WORLD SCIENTIFIC PUBL CO PTE LTD  

The Tachibana-wan coal-fired power station was constructed on land that was reclaimed using the soil that came from cutting through half of a small island while balancing the amount of soil. The power station has been generating for three years. When the electric utility provider projected the power station, it must have conducted an environmental impact assessment, and studied the environmental preservation measures. Moreover, after the power generation began, an environmental investigation was done as a follow up survey to study the environmental impact by the power station based on its construction and use. To study the environmental impact with smoke, the environmental density of sulfur dioxide around the power station was investigated. It fell below the environmental standards at all the environmental measurement points during this investigation. Moreover, a big difference was not seen before and after the beginning of the power generation and the change in these data was in the normal range. As a result of the environmental impact assessment, the contribution density of the power station was near the quantitative limit and a low value. To study the environmental impact with warm wastewater, the water temperature in the bay was investigated. A big difference was not generally seen before and after the beginning of the power generation though the water temperature slowly rose at the discharge point of the warm wastewater but the change of these data was in the normal range. As for the environmental impact, a clear judgment was difficult only from the environmental investigation. It is necessary to set a new environmental indicator to judge the environmental impact. Moreover, as for a new environmental assessment system, it is necessary to introduce a strategic environmental assessment.

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Language：English   Publisher：WORLD SCIENTIFIC PUBL CO PTE LTD  

In Romania, the communist planned economy system was in place for 42 years but ended due to a revolution in 1989. An environmental administration was started 1990. In order to assist with environment related activities, one of the authors worked in Bucharest for two years from March 2002 to March 2004 as a JICA (Japan International Cooperation Activity) member. One of the most important problems regarding environmental protection in Romania is waste management. In Japan, the regulations and penalties system of waste management have been used for a long time. However, there are many serious problems with the system, such as a decrease in waste disposal facilities and illegally disposed waste. The authors studied a new plan that uses a certification system in order to promote recycling industries. This system is both efficient and inexpensive so it is possible that this method of waste management could be transmitted to Romania.

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Language：English   Publisher：WORLD SCIENTIFIC PUBL CO PTE LTD  

A Liquid-Core Waveguide (LCW) detection system for high sensitive determination of tegaful (FT) was developed. In this system the LCW cell was connected to the end of a hollow cathode lump and the other end to a UV spectrometer. A sample solution containing FT was pumped to the LCW cell through a T-shaped connector. A UV absorption of analyte was detected by the UV spectrometer. The configuration of connectors of LCW cell to the light source and the UV detector was designed. Stable and high responses of FT were obtained in a double tube system in which an edge of LCW cell was covered with another tube with large diameter was set in the T-connector. It was found that the UV absorption response of FT obtained in this LCW system depends on the core length and the concentration of FT. The sensitivity of FT obtained by using 65 cm of the LCW cell length was 10-fold higher than that of using 1 cm cell which was often used with a conventional UV-visible detector.

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Language：English   Publisher：NATURE PUBLISHING GROUP  

Objective: To evaluate serum concentrations of trace elements in tuberculosis (TB) patients with or with out human immunodeficiency virus (HIV) coinfection before and after anti-TB chemotherapy.
Subjects: A total of 155 TB patients, 74 of which were coinfected with HIV, and 31 healthy controls from Gondar, Ethiopia.
Methods: Serum levels of copper, zinc, selenium and iron were determined using an inductively coupled plasma mass spectrometer from all subjects at baseline and from 44 TB patients (22 with HIV coinfection) at the end of an intensive phase of anti-TB chemotherapy.
Results: Compared with the control group, the concentrations of iron, zinc and selenium were significantly lower (P < 0.05) while that of copper and copper/zinc ratio was significantly higher (P < 0.05) in the serum of TB patients. TB patients with HIV coinfection had significantly lower serum zinc and selenium concentrations and significantly highercopper/ zinc ratio compared to that in TB patients without HIV coinfection (P < 0.05). The serum concentration of zinc had significantly increased at the end of intensive phase of anti-TB chemotherapy in patients without HIV coinfection (P < 0.05). An increase in serum selenium level was observed in TB patients with or without HIV coinfection after therapy. On the contrary, serum copper concentration and copper/zinc ratio declined significantly after anti-TB chemotherapy irrespective of HIV serostatus (P < 0.05).
Conclusions: The results indicate that TB patients have altered profile of trace elements in their sera. This warrants the need for further investigations so that strategies for trace elements supplementation can be planned in addition to their potential as diagnostic parameters in monitoring responses to anti-TB chemotherapy.

DOI： 10.1038/sj.ejcn.1602352

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This study was aimed at assessing the serum levels of vitamin A, copper, zinc, selenium, and iron among adult Vietnamese with and without iron-deficiency anemia. Blood was collected from adult Vietnamese living in the midland of northern Vietnam. One hundred twenty-three subjects in the age range 20-60 yr were included in the study. Anemia, where the concentration of hemoglobin in whole blood is less than 120 g/L in females and 130 g/L in males, was found in 30% (37/123) of the study population. The levels of vitamin Aand selenium in the sera of anemic subjects (n ≤ 37) were significantly lower than that in nonanemic group (n ≤ 86). On the other hand, no significant differences were observed in the concentrations of copper and zinc between the two groups. This study was the first to show serum levels of trace elements in adult Vietnamese, providing useful baseline information for further studies. © Copyright 2006 by Humana Press Inc. All rights of any nature, whatsoever, reserved.

DOI： 10.1385/BTER:111:1:1

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The electrochemical behavior of an enzyme sensor for glucose using a gold electrode modified with thiol self-assembled membrane and osmium complex gel as an electron transferring mediator has further been investigated by electrochemical analysis. The gold electrode was initially coated with aminomethanethiol self assembling mono layer membrane(thiol-SAM) and then immobilized with glucose oxidase using poly(vinylpyridine-co-allylaniine) (PVP-co-AA), gel coordinated with osmium bipyridine complexes (GOD/Os-PVP-co-AA gel). The cleaning condition of the surface of the Au electrode prior to coating thiol SAM was optimized for reduction of interference caused by concomitant compounds. It was found that interfering influence was most efficiently reduced in the case of use of the Au electrode immersed into nitric acid. The current ratio with a thiol coated gold electrode modified with Os-PVP-co-AA gel in glucose solution in the presence to absence of ascorbic acid, acetaininophen, and uric acid (ID+I/I-I) was 1.006, 1.014, and 1.018, respectively. The peak current response of glucose in the electrode modified with thiol SAM was dropped to 60 - 98 % as compared with that without thiol SAM.

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Layered double hydroxide (LDH) has been used to remove phosphate ion in water as an effective adsorbent of this anion at low concentration. LDH which contains Mg2+ and Al3+ as divalent and trivalent metals respectively was prepared as has been published by many authors. A fixed portion of this LDH was suspended in the weakly basic solution containing phosphate. The suspension was stirred moderately followed by filtration. The concentration of phosphate ion in the filtrate was determined by the molybdenum blue method. The result indicates that the LDH used in this experiment was effective in removing phosphate from water. Furthermore, it was also certified that the phosphate anions removed from water were quantitatively transferred onto the solid of LDH.

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Language：Japanese   Publisher：Japan Society for Analytical Chemistry  

A novel glucose sensor base on an osmium-complex modified polypyrrole was prepared and evaluated. Four new-type osmium-complexes ([Os(bpy) 2(py(4)-bpy)]2+/3+, [Os(bpy)2(py(3)-bpy)] 2+/3+, [Os(bpy)2(pyro-pri)Cl]+/2+, and [Os(bpy)2(vi-bpy)]2+/3+) were synthesized, and the kinetic parameters analyzed. A hydrophilic redox polymer with an osmium-complex was modified by electrolytic copolymerization on the surface of a platinum electrode. The effects of the polymer concentration, times of the scan, dissolved oxygen, and concomitant compounds, and a calibration curve for measurements of glucose were analyzed. The catalytic currents of synthesized osmium-complexes were observed. The relationship between glucose and the oxidation current was examined using the sensor under the optimum conditions. A linear relationship was obtained over the range of 0.9-100 mmol dm-3 glucose. It was measured in the presence of ascorbic acid or uric acid. These compounds did not affect the response current. The lifetime of the sensor was also examined. The analytical values were constant for 9 days when the sensor was stored in a pH 7.07 phosphate buffer solution at 4°C.

DOI： 10.2116/bunsekikagaku.51.1165

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Language：English   Publisher：CHEMICAL SOC JAPAN  

The coastal seawater sample was filtered with a membrane filter (pore size 0.45 mu m), and the filtrate was further filtered with an ultrafiltration filter (molecular weight permeation limit of 10000 Da). Then, major-to-ultratrace elements in the particles which remained on the membrane filter, the membrane-filtered seawater, and the ultrafiltered seawater were determined by ICP-AES (inductively coupled plasma atomic emission spectrometry) and ICP-MS (inductively coupled plasma mass spectrometry). From these analytical results, the fractional distributions of each element in the particle, large molecule and small molecule fractions of seawater were estimated, where the distributions of the elements in the large molecule fraction were obtained as the differences between the elemental concentrations in membrane-filtered and ultrafiltered seawaters.
Furthermore, laboratory-made salts (Salts I-III) were prepared from original, membrane-filtered, and ultrafiltered seawaters. The concentrations of major-to-ultratrace elements in laboratory-made salts were also determined by ICP-AES and ICP-MS. It was found that alkali metals, alkaline earth metals, oxoanion-forming elements (V, Mo, W, U) and Cd were mostly contained in the small molecule fraction of seawater, and ca. 95-100% of them in salt, except for V, originated from those in the small molecule fraction. More than 50% of Al, Mn, Fe, Co, Ga, Y, rare earth elements (REEs) and Pb were contained as the particle constituents in seawater, but their intakes into salt were less than 50%. In addition, the fractional distributions of the following elements in the large molecule fraction of seawater were: Al 10%, Mn 4%, Fe 2%, Cu 23%, Zn 7%, Y 5%, REEs 3-15%, and Pb 30%. On the other hand, the intake factors of these elements in salt from the large molecule fraction were: Al 40%, Mn 5%, Fe 28%, Cu 20%, Zn 30%, Y 7%, REEs 5-30%, and Pb 55%. The results obtained in the present experiment suggest that the distributions of the elements in natural salt greatly depend on the chemical forms in seawater.

DOI： 10.1246/bcsj.73.1179

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The simultaneous multielement determination of trace elements in seawater, especially hydride- and oxoanionforming elements, has been investigated by inductively coupled plasma mass spectrometry with the aid of lanthanum coprecipitation preconcentration. The optimum pH in lanthanum coprecipitation was pH 9.5; at this value, trace elements were well recovered and major constituents of seawater such as Na, Mg, K, and Ca were significantly reduced in the concentrated solutions. The recovery values obtained for V, Cr(III), Mn, As(III), As(V), Se(IV), Y, Sn, Sb(III), Sb(V), W,Bi, and U were more than 85% after lanthanum coprecipitation, while Cr(VI), Se(VI), and Mo(VI) provided poor recoveries of less than 30%. The reproducibility for coprecipitation was within 5% as relative standard deviation. The present method was applied to the determination of trace elements in coastal seawater reference material CASS-3. The analytical values for Mn, As, V, Y,Sb, W, and U were in fairly good agreement with the certified or literature values.

DOI： 10.1246/bcsj.73.895

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Language：Japanese   Publisher：海洋化学研究所  

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Language：Japanese   Publisher：JAPAN SOC ANALYTICAL CHEMISTRY  

The distributions of major-to-ultratrace elements into natural salt from coastal seawater in a salt-preparation process were investigated by ICP-AES (inductively coupled plasma atomic emission spectrometry) and ICP-MS (inductively coupled plasma mass spectrometry) with preconcentration using a chelating resin. The coastal seawater samples were collected off-shore near to the Nie coast, where Agehama-made salt is produced by a classical Agehama method. Natural salt was produced from original coastal seawater in the laboratory in a similar manner to the Agehama method. First, the seawater samples were filtered with a membrane filter (pore size of 0.45 mu m), and the elements in the dissolved fraction (filtrate) and in the particulate fraction (particulate on the filter) were determined by ICP-AES and ICP-MS. The analytical results for seawater indicate that alkali elements, alkaline earth elements, and oxoanion-forming elements (V, Mo, W, U) were dominantly in the dissolved fraction, while other elements such as Al, Fe, Pb and rare earth elements were mostly in the particulate fraction. The elements in laboratory-made salt and Agehama-made salt were also determined by ICP-XES and ICP-MS after dissolving them in a 0.1 M HNO3 solution. Although the concentrations of trace elements in laboratory-made salt and Agehama-made salt were almost at the same levels for 27 elements among 34 elements within a factor between ca. 1/5 and 5, Ba, Mn, Cd and Pb in Agehama-made salt were much higher (8-30 fold) in concentration than those in the laboratory-made salt. Based on the experimental results mentioned above, the distributions of major-to-ultratrace elements into natural salt from seawater were discussed, taking into consideration the preparation process of natural salt.

DOI： 10.2116/bunsekikagaku.49.111

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The multielement determination of major-to-trace elements in insoluble particulates of solar salt was carried out by ICP-AES and ICF-MS. A solar salt sample (30 g) was dissolved in 11 of pure water to adjust its solution salinity to be almost the same as that of seawater. When the solar salt sample solution was filtered using a membrane filter (pore size 0.45 mu m), the residue on the filter was defined as the insoluble particulates and the filtrate as the soluble constituents. The insoluble particulates were decomposed together with the membrane filter by an acid digestion method using HNO3, HF, and HClO4. As a result, 36 elements in the insoluble particulates could be determined at % to sub-mu g g(-1) levels by ICP-AES and ICP-MS. Taking into consideration the present results along with the analytical results for the soluble constituents reported in a previous paper, alkali elements, alkaline earth elements, Ma and Cd were found mainly in the soluble constituents of solar salt, while Al, Ti, V, Fe, Co, Ga, Y Sn, and rare-earth elements (REEs) were found in the insoluble particulates. Iron, Co, Y, Sn, and REEs in the insoluble particulates were partly leached into the acid solution when the solar salt sample was dissolved in a 0.1 M HNO3 solution. Thus, it is considered that these elements are dissolved as colloidal matter adsorbed on particulates in seawater. On the other hand, because Mn, Cu, Zn, and Pb were found in both the insoluble particulates and the soluble constituents, these elements in the insoluble particulates were easily leached in a 0.1 M HNO3 solution. These results indicate that Mn, Cu, Zn, and Pb are contained as acid-soluble forms in the insoluble particulates. Moreover, the relative abundances of the elements normalized to the Al concentrations in the insoluble particulates of solar salt and the marine sediment standard material (NIES No. 12) showed a good linear correlation, which suggests that the insoluble particulates in solar salt are an origin of marine sediment.

DOI： 10.2116/bunsekikagaku.48.897

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Language：English   Publisher：CHEMICAL SOC JAPAN  

The multielement determination of trace elements in coastal seawater by inductively coupled plasma mass spectrometry has been investigated with the aid of chelating resin preconcentration. First, each coastal seawater sample (250 ml) was treated with a chelating resin (Chelex 100) at pH 6 for preconcentration of trace elements. After filtration with a glass filter, the resin on the filter was carefully rinsed with 8 ml of 1 M ammonium acetate solution. Then, trace elements adsorbed on the resin were eluted with 6 mi of 2 M HNO3. As a result, the preconcentration factor of 41.7 fold was obtained, with the total concentration of matrix elements (Na, K, Mg, and Ca) less than 200 mg dm(-3). The recovery values were larger than 80% for 22 elements among 29 elements determined. The present method was applied to the determination of trace elements in the coastal seawater certified reference material CASS-S, issued from National Research Council of Canada (NRC), as well as to the coastal seawater sample collected from Tokoname off-shore.

DOI： 10.1246/bcsj.72.2253

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The multielement determination of trace elements in river water certified reference materials (JAC 0031 and JAC 0032), issued from the Japan Society for Analytical Chemistry, has been carried out by ICP-MS and ICP-AES. The chelating resin preconcentration method, using Chelex(R) 100, was employed for the enrichment of most trace elements, including rare-earth elements, while some of the elements were determined by direct sample introduction without any pretreatment. As a result, the concentrations of 37 elements in river-water certified reference materials were obtained in the present experiments. concentrations ranged from 1.23x10(-3) gl(-1) for Ca to 1.2x10(-12) g l(-1) for Tm. The analytical values for Ca, Na, Mg, K, Al, B, Fe, Cu, Zn, and Mn were almost in good agreement with the certified values, while that for Cr was not because of poor recovery in preconcentration. In addition, the REE (rare earth elements) distribution pattern of JAC 0031, normalized by the REE concentrations of continental shale, was compared with those of the Lake Biwa surface water and samples from 24 rivers in Japan.

DOI： 10.2116/bunsekikagaku.47.109

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