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Volume 36, Issue 11
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Atsushi MIZUIKE1987 Volume 36 Issue 11 Pages 635-646
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSModern instrumental analytical techniques are highly sensitive and selective, still their direct applications to inorganic trace analysis are limited only to some favorable cases because of various effects of the matrix. Preconcentration, therefore, is frequently required to determine trace elements at the pg/g, ng/g or low μg/g levels in a variety of inorganic and organic matrices with sufficient precisions and accuracies of the analytical results. The present review surveys the present status and future prospects of preconcentration techniques. Based on recent studies carried out in the author's laboratory, the following topics are mainly discussed; control of contamination and losses of trace elements, preconcentration from large volumes of aqueous solutions, microscale preconcentration techniques for microsamples of high-purity materials, and preconcentration in trace metal speciation in natural waters.View full abstractDownload PDF (1960K) -
Takashi TANAKA, Kunishige HIGASHI, Akinori KAWAHARA, Shin-ichi WAKIDA, ...1987 Volume 36 Issue 11 Pages 647-651
Published: November 05, 1987
Released on J-STAGE: May 07, 2010
JOURNAL FREE ACCESSTrace amount of ferric ion (up to 0.5μg) in waters was preconcentrated on a cation-exchange column (Dionex cation seperator column for ion chromatography, 3 mmφ × 200 mm), eluted with 5 × 10-3 M EDTA solution (pH 3.2, flow rate: 1.0 ml/min), and determined by measuring the UV absorbance of the Fe(III)-EDTA complex in the eluent at 260 nm. The column and the eluent were warmed at 40 °C. Linear calibration curves were obtained for 0100 ppb and 020 ppb of ferric ion using 5 ml and 25 ml sample solutions (0.05 M sulfuric acid solution), respectively. Relative standard deviations obatained in each 10 measurements for 5 ml (50 ppb) and 25 ml (10 ppb) of the ferric ion solutions were 3.2 and 3.0%, respectively. The present method was applied to the determination of dissolved iron, contained ionic iron and complexed iron, in lake and river waters. Ferrous ion in water was oxidized to ferric ion by addition of hydrogen peroxide (0.005%). Complexed iron was decomposed to ferric iron by heating the sample water with potassium peroxodisulfate.View full abstractDownload PDF (625K) -
Rokuro KURODA, Yutaka HAYASHIBE, Koichi OGUMA1987 Volume 36 Issue 11 Pages 652-655
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA combined anion-exchange/spectrophotometric method has been worked out for the determination of traces of tin in environmental materials. The sample is wet-ashed by a sulfuric acid-nitric acid mixture, if necessary, together with hydrofluoric acid. The tin is collected by anion-exchange on a Bio-Rad AG 1 (SO42-) column from 0.5 M sulfuric acid - 0.05 M oxalic acid solution. After washing the column with 3 M hydrochloric acid-1% ascorbic acid, the tin is eluted with 0.5 M sulfuric acid-0.3% hydrogen peroxide solution. The tin is subsequently determined spectrophotometrically with Pyrocatechol Violet. Results of the determination of tin in three environmental standard reference materials including Human Hair, Mussel and Pond Sediment are compiled. Relative standard deviations are in the range of 1% (for 10 ppm level of tin) to 24% (for 1 ppm level of tin).View full abstractDownload PDF (488K) -
Kazuhisa YOSHIMURA1987 Volume 36 Issue 11 Pages 656-661
Published: November 05, 1987
Released on J-STAGE: May 07, 2010
JOURNAL FREE ACCESSUltra-trace amounts of Bi (0.0120.5 nmol) in various samples were preconcentrated as chloro complexes from 0.10.6 mol dm-3 chloride solution with an anion-exchanger column {0.5g of Dowex 1-X8 (100200 mesh) in the chloride form}. With the column, water samples up to at least 1 dm3 could be treated. The Bi in the column was desorbed with a 0.15 mol dm-3 sulfuric acid solution at a flow rate of 1.2 cm3 min-1, mixed with a solution containing 1 mol dm-3 potassium iodide at a flow rate of 0.3 cm3 min-1, and then introduced into a flow-through cell, the lightpath portion of which was filled with an anion-exchanger (QAE-Sephadex A-25). The light attenuation due to the iodo complexes of Bi selectively concentrated on the anion-exchanger of the flow-through cell could be measured directly at 472 nm with high precision. The calibration curve for Bi was linear. The colored bismuth-iodo complexes were easily desorbed with an acidic EDTA (0.001 mol dm-3) solution, so that the cell could be used repeatedly for the measurements. The present method was applied to the analysis of various samples such as rocks and metals.View full abstractDownload PDF (844K) -
Hideo AKAIWA, Hiroshi KAWAMOTO, Hiroaki KINOSHITA1987 Volume 36 Issue 11 Pages 662-665
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSAn increase in the number of sulfonic acid group in a chelating agent-loaded resin was shown to prevent the resin from being eluted upon treatment with an acid or salt solution. Among chelating agents examined, 4, 7-dipheny1-1, 10-phenanthroline disulfonic acid (BPS) was adopted to prepare a chelating agent-loaded resin and applied to concentrate Cu(II) in natural waters before instrumental analysis. Copper(II) was quantitatively retained on the BPS-resin column (7 mmφ × 17 mmH ), flow rate of sample water (pH=2) being 1.0 cm3 min-1, and Cu(II) retained on the column could be eluted with 10 cm3 of 0.1 mol dm-3 EDTA solution. Copper(II) was then determined accurately by AAS.View full abstractDownload PDF (640K) -
Collection and removal of micro amounts of mercury (II) ion in water by using the tea adsorbentMasaru KIMURA, Yayoi NAGAI1987 Volume 36 Issue 11 Pages 666-671
Published: November 05, 1987
Released on J-STAGE: May 25, 2010
JOURNAL FREE ACCESSThe adsorption properties of mercury(II) ion on surface of the Japanese green-tea (powder tea) particles were examined by the measurements of the adsorption percentage and the adsorption isotherm under various conditions, and a method to collect and remove the micro-amounts of mercury (II) ion in aqueous solutions is described. The powder tea was treated with formaline in a dilute sulfuric acid. A 100 ml sample solution containing HgCl2 was mixed with 50 mg of the treated tea under stirring for a few min. The solution was then centrifuged and the concentrations of Hg(II) in the supernatant solution were determined with the flameless atomic absorption spectrometer. 5100 μg Hg(II) in a 100 ml solution at pH 39was adsorbed over 90% on 50 mg of the tea. The adsorption equilibrium constant (K) and the maximum adsorption amount in the Langmuir equation was determined at pH 39 to be 6.4 ×104 dm3 mol-1 and 53 mg g-1, respectively. These values were almost the same as the corresponding ones for the activated carbon adsorbent. It was found that 50 μg Hg(II) in a 100 ml solution containing 1030 g Zn(NO3)2· 6H2O was quantitatively adsorbed on 50 mg of the tea with K =1.8 × 105 dm3mol-1 and that the maximum adsorption amount decreased to 6 mg g-1. Addition of 8-hydroxyquinoline or 1, 10-phenanthroline did not change greatly the adsorbability. On the other hand, addition of EDTA (Na2[H2edta]) inhibited completely the Hg (II) adsorption on the treated tea. The tea can be reused over 4 times as the adsorbent, after the Hg(II) is washed away and desorbed well with hydrochloric acid of 6 mol dm-3.View full abstractDownload PDF (827K) -
Akinori ISOZAKI, Kozo UEKI, Hajime SASAKI, Satori UTSUMI1987 Volume 36 Issue 11 Pages 672-677
Published: November 05, 1987
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSA sensitive method is investigated for the simultaneous determination of trace Cd and Pb by AAS. The method is based on the direct atomization of metaladsorbed chelating resin by introduction of a resin-suspension into a graphite furnace. To a 250 ml sample solution (pH 4.0) containing less than 25 ng of Cd and 0.50 μg of Pb, 0.05 g of chelating resin (NH4 form, below 400 mesh) is added, and the mixture is stirred for 30 min. After collection of the resin on a membrane filter, 5.0 ml of resin-suspension is prepared by adding water to the resin, and 10 μl of the suspension (resin : 0.1 mg) is injected into a graphite furnace. The metal-adsorbed resin is initially dried at ca. 130°C for 20 s, subsequently heated at ca. 700°C for 90 s in the atmosphere, and metal on the resin is atomized at ca. 1900°C for 3 s in argon atmosphere (argon flow rate: 2 1 /min). Peak areas of Cd and Pb are simultaneously measured without the background correction. The calibration graphs are linear up to 100 ppt for Cd and up to 2.0 ppb for Pb. For the determination of 114 ppt Cd and 1.46 ppb Pb in a river water sample, the relative standard deviations are 2.9% and 2.8%, respectively, on 7 repeated measurements.View full abstractDownload PDF (982K) -
Shizuko HIRATA, Kazuto HONDA, Takahiro KUMAMARU1987 Volume 36 Issue 11 Pages 678-682
Published: November 05, 1987
Released on J-STAGE: May 07, 2010
JOURNAL FREE ACCESSA method utilizing a microcolumn of chelate resin, Muromac A-1, has been developed to increase the sensitivity for Ni and Co by AAS. A sample (pH 36) solution at the flow rate of 5.0 ml min-1 was merged with ammonium acetate buffer (pH 7) at the flow rate of 5.0 ml min-1 and made to pass through the column. After segmented by Ar at the flow rate of 0.2 1 min-1, chelated Ni and Co were eluted sequentially with 2 M nitric acid at the flow rate of 4.85 ml min-1 and determined directly by the AAS, using a FIA system. This on-line preconcentrating FIA/AAS system using a 20 ml sample gave enhanced sensitivities for Ni and Co which were about 100 times better than those obtained by the conventional continuously aspirated AAS. Relative standard deviations of the method were 2.7% (n=10) for 50 ppb of Ni and 2.5% (n=3) for 40 ppb of Co standards, and detection limits (3σ) were 4.1 ppb for Ni and 2.9 ppb for Co. The sampling rate was 11 samples h-1. This method was successfully applied to the analysis of standard reference material (NIES No. 1).View full abstractDownload PDF (658K) -
Hiroyuki FUKUDA, Jun TSUNODA, Ken MATSUMOTO, Kikuo TERADA1987 Volume 36 Issue 11 Pages 683-687
Published: November 05, 1987
Released on J-STAGE: May 25, 2010
JOURNAL FREE ACCESSA complexing material, thionalide (2-mercapto-N-2-naphthylacetamide) loaded on silica gel (thionalide/SG) was prepared by a modified previous method, and used for preconcentration of trace Sb in water samples. Antimony(III) was quantitatively retained on the loaded gel from solution of 2 mol dm-3 hydrochloric acid-pH 3.0 in batch experiments. The retention capacity of the loaded gel was 562 μg Sb(III) g-1 in 0.6 mol dm-3 hydrochloric acid. Antimony was quantitatively retained on the column filled with 1.0 g of the gel at a flow velocity of 2 cm min-1. The Sb retained on the column was completely eluted with 1520 cm3 of 6 mol dm-3 hydrochloric acid, and directly determined by hydride generation AAS using sodium tetrahydroborate as a reductant. Antimony(V) was incompletely retained on the column, therefore, the species should be reduced to tervalent state by digesting the sample in 0.6 mol dm-3 hydrochloric acid containing potassium bromide prior to sample passage onto the column. The calibration graph was rectilinear over the range of 0.510ng cm-3, the limit of detection (3σ) was 0.4 ng cm-3, and the relative standard deviation for the samples containing 75 ng and 150 ng of Sb in 500 cm-3 (n=5 and 7) was about 1.4% in both cases. Antimony contents of near-shore seawater and river water were determined by the present method.View full abstractDownload PDF (668K) -
Tasuku AKAGI, Hiroki HARAGUCHI1987 Volume 36 Issue 11 Pages 688-692
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSAn on-board preconcentration apparatus for trace elements in seawater has been newly developed. The technique employed is batch preconcentration using Chelex 100 chelating resin, which is an excellent pretreatment technique prior to the ICP-AES measurement. The advantage of the method have relatively short time and simple procedure for collecting many trace metals from seawater. The apparatus was designed so as to perform the following procedures almost successively, i. e. filtration of sample, stirring sample with resin, recovering of resin, and elution of analytes on the resin. The optimum preconcentration conditions were examined for stirring time and pH adjustment by using ICP-AES. It has been found that many elements such as Al, Co, Ni, Cu, Zn, Y, Cd and Pb can be preconcentrated by almost 100 times at pH 6, and Fe(III), Mn(II), Ti and V(V) at pH 3. The time taken for treatment of one sample was 2 or 3 h. The detection limits obtained with ICP-AES after preconcentration were below 100 ng/l.View full abstractDownload PDF (875K) -
Yasuo TAKAHASHI1987 Volume 36 Issue 11 Pages 693-697
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSFor highly sensitive and selective determination of B by ICP-AES, ion exchange method was applied for preconcentration and separation by using B specific resin, Amberlite XE-243. Small columns (3 mm × 50 mm) were prepared by charging polyethylene tube with 0.12 g of the resin (4080 mesh). Neutral sample above pH 6 containing up to 2 μg of B was passed through the column at a flow rate of 1 ml/min by a peristaltic pump. Then, 0.5 M HCl was passed at a reverse direction to the sample flow to elute boron quickly from the column. Without diluting to volume, the effluent was introduced to a nebulizer of the ICP apparatus and sprayed into the plasma. Emission intensity of B was intergrated for 80 s at B I 249.773 nm. Among foreign ions tested, carbonate ion and Fe(III) chelate ion were found to interfere with the determination. The former was removed beforehand as CO2 from sample by boiling under reduced pressure. The latter was washed out from the column by passing NH4Cl solution after sample. This method was applied to river waters and standard steels, and the results obtained showed that B was successfully concentrated from samples at ppb level and separated from Fe(III) ion.View full abstractDownload PDF (857K) -
Yu-Ming HSUEH, Kazuo MIYAMURA, Tsuguo SAWADA, Yohichi GOHSHI1987 Volume 36 Issue 11 Pages 698-701
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSLaser induced photoacoustic spectroscopy (LIPAS) was applied to determine the microamount of Cd2+ in aqueous solution by combining the preconcentration procedure of Cd2+, which is adsorbed onto solid resin XAD-2 as an 8-quinolinol complex. The optimum conditions were discussed for the preconcentration procedure and the LIPAS measurement. To avoid the unclear dependence of PA signal for the multiparticle samples, one particle examination by using well focused Ar+ laser as a light source revealed useful. A linear response was obtained over the concentration range from 7 to 190 ng Cd2+ per particle. This amount corresponds to the solution concentration of 0.088.3 ppm depending on the rate of preconcentration. Consequently the combination of preconcentration with adsorbent and one particle LIPAS measurement proved to be an effective method for the analysis of Cd2+ in aqueous solution.View full abstractDownload PDF (642K) -
Elimination of major interferences anions with high-capacity ion exchange resin columnTetsuo OKADA1987 Volume 36 Issue 11 Pages 702-706
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSDetermination of trace nitrite ion by ion chromatography (IC) with large volume injection method is described. Large volume injection is an excellent concentration mode in its simplicity of instruments. Elimination of interferences from major anions in the concentration step of trace nitrite were attempted by using a large ion exchange capacity resin, the capacity of which was 100 times higher than a common ion exchange resin for IC, and direct UV detection. As a result of the various investigations for eluent conditions, chloride ion was a best eluent anion. The present method permitted to concentrate 1050 ml of a sample solution without the interferences from major anions in the concentration step and the UV detection. Chloride ion employed as an eluent anion did not interfere with the detection of nitrite ion at 210 nm. Detection limit for nitrite ion was 0.1 ppb and relative standard deviation for concentrating 20 ml of 1 ppb nitrite solution was 3.5%. Nitrite ion was determined without interferences from the major anions on the concentration of 30 ml of 1 ppb nitrite solution containing 50 ppm chloride and 10 ppm nitrate by means of the present method. Moreover, this method was applied to the determination of nitrite ion in tap water which contained chloride (7.5 ppm), nitrate (1.2 ppm) and sulfate (6.6 ppm) as major anions.View full abstractDownload PDF (750K) -
Kenichi AKIBA, Kousaburo OHASHI1987 Volume 36 Issue 11 Pages 707-711
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSExtraction of U(VI) from weakly acidic media has been investigated by using alkyl derivatives of 8-quinolinol; 5-octyloxymethyl- (HO8Q ), 5-decyloxymethyl-(HO10Q) and 5-dioctylaminomethyl-8-quinolinol (HN8Q). The ability for the extraction of U increased in the order, HO10Q<HO8Q<HN8Q. Supported liquid membranes (SLM) containing these long-chain 8-quinolinols as a mobile carrier have been studied for their ability to transport and concentrate U from dilute solutions. Uranium was effectively transported by the HO8Q and HO10Q carriers from the feed solutions of pH around 5 into the stripping solution of dilute nitric acid against its concentration gradient. The concentration of U in the feed solution decreased as indicated by, ln ([U]f, t/[U] f, 0) = -kobst. Variation of carrier concentration and the feed pH gave a slight effect on kobs values. The recovery of U into the stripping solution attained 95% with the HO8Q carrier and 70% with the HN8Q carrier, leaving a small portion of U in the membrane layer. Approximately quantitative recovery of U was achieved by the HO10Q carrier; U was sufficiently concentrated from dilute solutions such as seawater spiked with 10-6 mol dm-3 U.View full abstractDownload PDF (720K) -
Keiichi FUKUSHI, Kazuo HIIRO1987 Volume 36 Issue 11 Pages 712-716
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA new analytical procedure for bromide ion in seawater using capillary type isotachophoresis and a membrane separation unit for pretreatment, was developed. The unit is a double-tube structure, consisting of an inner microporous polytetrafluoroethylene (PTFE) membrane tube and an outer glass tube. Analytical procedure is as follows: A mixed solution of 10 ml of seawater sample, 0.3 ml of 9 M sulfuric acid and 0.7 ml of 0.02 M potassium permanganate is circulated through the outer glass tube for 20 min at a flow rate of 7 ml/min. The temperature of the membrane separation unit is adjusted to 40 °C. During the circulation, bromide ion in the sample solution is oxidized to bromine. The bromine permeates through the PTFE membrane and dissolves in 1.5 ml aliquots of a mixed solution of 10 ml of distilled water, 0.5 ml of 0.1 M acetic acid and 2.0 ml of 3% hydrogen peroxide placed in the inner PTFE tube as the reduced bromide ion. Then, 10 μl of the solution containing bromide ion is injected into an isotachophoresis apparatus equipped with a potential gradient detector and a 15-cm-long main column connected to a 20-cm-long precolumn. The leading electrolyte is a methanol solution containing 5 mM perchloric acid and 10 mM tris (hydroxymethyl) aminomethane. The terminating electrolyte is 10 mM sodium fluoride solution. The migration current is set at 200 μA for 18 min and then reduced to 50 μA. A linear working curve was obtained for artificial seawater samples containing up to 100 mg/l of bromide ion. The recovery of bromide ion was 42 ± 3%. The relative standard deviation of the method was 5.0% (n=7). The lower determination limit of bromide ion was 9.0 × 10-2 mg/l. The proposed method was applied to the determination of bromide ion in surface and bottom seawater samples collected around the coastal area of Osaka Bay. Sufficient recovery was obtained in the standard addition experiments.View full abstractDownload PDF (907K) -
Toyoaki AOKI, Toshikatsu NOSAKA, Makoto MUNEMORI1987 Volume 36 Issue 11 Pages 717-721
Published: November 05, 1987
Released on J-STAGE: May 25, 2010
JOURNAL FREE ACCESSContinuous flow determination of ultratrace sulfide in water based on membrane separation followed by chemiluminescent reaction is described. A doubletube system, with an inner tube of microporous poly-(tetrafluoroethylene) (PTFE) (i.d. 1.0 mm, o.d. 1.8 mm, length 500 mm) and an outer tube of PTFE (i.d. 2.0 mm, o.d. 4.3 mm, length 500 mm) were used. Hydrogen sulfide, produced by mixing a sample with 9 M H2SO4 solution and 0.1 M NaHCO3 solution in the outer tube, permeates microporous PTFE and reacts with luminol reagent solution in the inner tube to produce chemiluminescence. This chemiluminescence was detected with photomultiplier tube. The cheminescent intensities were proportional to concentrations of sulfide from 2 × 10-8 to 1 × 10-6 M. The lower limit of detection (S/N=3) of sulfide by this method was 8 x 10-10 M (25 ppt). The relative standard deviation (n=4) was 1.1% at 5 × 10-7 M. The time required for a 98% response was 3.5 min. Sulfide was selectively determined without interference from Fe(III), Co(II), and other heavy metals because of using membrane separation process.View full abstractDownload PDF (663K) -
Nobuaki SASAOKA, Kiyotoshi MORISIGE, Tsunenobu SHIGEMATSU, Yasuharu NI ...1987 Volume 36 Issue 11 Pages 722-727
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSSimple preconcentration and separation of trace amounts of Th(IV) from rare earth ions(III) with a chelating filter paper "Expapier F-2" (2-hydroxypropyl-iminodiacetic acid) had already been described. In this paper, the method for preconcentration and separation of the trace constituent of Sc(III) and Zr(IV) in Fe (III) and Al(III) was described. The quantitative retention pH of various metal ions on Expapier F-2 were as follows; Sc(III) : 3.04.0, Zr(IV) : 0.52.5, Al(III), Fe(II) : >5.0, Fe(III) : 1.72.0. Metal ions retained on Expapier F-2 were eluted with a suitable eluting solution. By passing 20 cm3 of the eluting solution containing 10% hydroxylamine in 0.03 M sodium acetate-hydrochloric acid solution (pH 1.5) at a flow rate 5 cm3 min-1, Al(III) and Fe(III) were completely eluted from Sc(III). On the other hand, Zr(IV) binded at pH 1.0 was separated from various metal ions with 20 cm3 of 0.03 M sodium acetatehydrochloric acid solution (pH 0.75) at a flow rate 5 cm3min-1. Sc(III) and Zr(IV) remained on Expapier F-2 were completely eluted with 20 cm3 of 2 M and 4 M hydrochloric acid, respectively. These metal ions were determined by fluorometry, ICP-AES and/ or XRF method. The present method is useful for rapid preconcentration and simple separation of trace amounts of Sc(III) and Zr(IV) in much larger quan tities of Fe(III) and Al(III).View full abstractDownload PDF (881K) -
Kazumasa UEDA, Shun KITAHARA, Katsutoshi KUBO, Yoshikazu YAMAMOTO1987 Volume 36 Issue 11 Pages 728-734
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA simple, rapid and sensitive method for AAS determination of Cd, Mn, Pb, Cu and Co in natural waters has been developed by utilizing synergistic extraction with STTA-TOPO-cyclohexane solution. Trace metals could be quantitatively separated and concentrated from natural water matrix by using a low concentration (1 mM level) of STTA and TOPO. The synergistic extract was directly injected into the graphite furnace and the reproducible absorption signal with little memory effect was obtained. The extracted adduct would produce multipliing effects on the AAS measurement, e.g., the prevention of volatilization of metal on the ashing stage, the depression of metal oxide formation and the extension of thermal contact area in the graphite furnace. Thus, the sensitization effect was recognized, simultaneously the depression of the interferences. The proposed method was applied to the analysis of river water, using a small volume of sample solution, and trace metals were successively determined within the relative standard deviation of 10%.View full abstractDownload PDF (1019K) -
Yukio NAGAOSA, Masato ONO1987 Volume 36 Issue 11 Pages 735-739
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA direct method has been developed for the differential-pulse polarographic determination of Se(IV) and Te(IV), based on the extraction of their diethyldithiocarbamates into ethyl acetate. The solvent extraction is performed by bubbling nitrogen through the aqueous phase (4.0 cm-3) and the organic phase (1.0 cm-3) for 5 min in a polarographic cell. Two differential-pulse polarographic peaks appeared at-0.70 V and-1.13 V vs. Ag/AgCl for Se(IV) and Te(IV), respectively. The calibration curves are linear over the concentration ranges 7.550 ng cm-3 for Se(IV) and 10100 ng cm-3 for Te(IV) in the aqueous phase. The lower limit of detection is 5.0 ng cm-3 in both metals. Selenium(IV) is separated for the other common metal ions by passing the sample solution (pH 3.03.5) through a cation exchange resin IR-120, because it can not be retained with the resin. The present method has been applicable to the determination of selenium in oyster tissue(NBS SRM 1566).View full abstractDownload PDF (787K) -
Kouji UENO, Eigo KOBAYASHI, Toshiyuki HOBO, Shigetaka SUZUKI1987 Volume 36 Issue 11 Pages 740-744
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA method for the determination of anionic surfactants, mainly dodecylsulfate was established. It is based on the flotation of ion pair, formed by the surfactants and Ethyl Violet, into solvent layer and successive spectrophotometric determination: Two hundred milliliters of sample was adjusted to pH 4.7 using acetate buffer and poured into a foam separation tube (33 mm i.d. × 360 mm, Pyrex glass). Then, it was added with 5 ml of toluene-methyl isobutyl ketone (9:1) mixture, while nitrogen was fed at very low flow rate through the sintered glass plate (No. 3). After 0.5 ml of 0.1% Ethyl Violet aqueous solution was injected by a syringe through the side septum, nitrogen flow rate was adjusted at 8.6 ml min-1and the solution was flotated for ten, min. Then the organic layer was removed and measured of its absorbance at 608 nm. The lower limit of determination was estimated to be 5 μg 1-1. The method has no difficulty in the phase separation and was applied successfully to the determination of total alkylsulfate contents in several water samples.View full abstractDownload PDF (627K) -
Keiya KOTSUJI, Kazumi WAKIYA, Shigehiko HAYASHI1987 Volume 36 Issue 11 Pages 745-749
Published: November 05, 1987
Released on J-STAGE: May 25, 2010
JOURNAL FREE ACCESSA spectrophotometric method for the determination of Zn in serum, based on the extraction flotation of 2-(5-bromo-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino) phenol (5-Br-PAPS)-Zn(II) chelate with the aid of tetrahexylammonium chloride (THA) as a collector and small nitrogen bubbles, has been developed. Only 0.1 ml of sample was necessary, because preconcentration for Zn in serum was carried out by the use of extraction flotation technique. Interference of Fe and Cu in serum could be removed by the masking action of 2, 2'-bipyridyl and salicylaldoxime, respectively. The recommended procedure is as follows. Serum (50 to 100 μl) mixed with 0.1 ml of 1 M hydrochloric acid was heated at 8095°C for 2 min. After cooling, 0.1 ml of trichloroacetic acid (0.05 g ml-1) solution was added, the mixture was shaken and centrifuged, and the supernatant solution was removed. Then, the precipitated proteins were washed two times with 0.5 ml each of water. To the combined supernatant solution, 1 ml of ascorbic acid (0.01 g ml-1) solution, 1 ml of 5 × 10-3 M 2, 2'-bipyridyl solution, 1 ml of 5-Br-PAPS (80μg ml-1) solution and 5 ml of 0.2 M carbonate buffer solution (pH 8.9) were added. After standing for 15 min, 1 ml of THA (0.008 g ml-1) solution was added and diluted to 20 ml with water. The solution (pH 8.79.1) was placed in a flotation cell with 0.7 ml of isopentyl alcohol-butyl acetate (2:1 in vol.). After bubbling nitrogen through the aqueous phase at 40 ml min-1 for 5 min, the organic phase was removed and make up to 1 ml with 0.2 ml of salicylaldoxime (0.01 g ml-1) ethanolic solution and ethanol, and its absorbance was measured at 556 nm. Zinc(II) was collected as 5-Br-PAPS-Zn (II) chelate with about 98% yield in the mixed solvent solution. Results were in good agreement with those of AAS method. Moreover, hemoglobin did not interfere at a concentration up to 0.3 mg hemoglobin ml-1 in serum.View full abstractDownload PDF (794K) -
Kohji ITOH, Ikuo ATSUYA1987 Volume 36 Issue 11 Pages 750-754
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA high sensitive, accurate, and simple method for the determination of ultra-trace amounts of Hg(II) in natural waters was established by AAS with the amalgamation on gold after a coprecipitation with chelating reagents. Ni(II) and dimethylglyoxime(DMG) were used as a carrier ion and complexing agent, respectively. Conditions for coprecipitating Hg(II) with Ni-DMG were examined, and 2-merucaptobenzotiazol(MBT) as an auxiliary chelating agent was added for facilitating the coprecipitation of Hg(II). The recovery of Hg (II) was improved by the addition of 5 mg of MBT from 35% to 100%. Based on these examinations, a recomendable analytical procedure has been established. A sample solution(50300 ml) was taken in a borosilicate glass beaker, and then 5 mg of Ni(II) was added as carrier ion. After addition of 35 mg of DMG and 5 mg of MBT, pH was adjusted with conc. ammonia water to 9. After standing 60 min at 60°C, the precipitate was collected by a fine glass frit filter (pore size 510 μm) and drying in oven for 60 min at 110°C. Enrichment factor of this method reached to 12000 when 300 ml of sample solution was used and the weight of coprecipitate obtained was 25 mg. Analytical blank was 0.20 ± 0.03 ng. Detection limit was 0.3 ppt. Relative standard deviation (ca. 2.14.8%) was shown for each measurement. This method was applied for the determination of Hg(II) in seawater and sewagesludge.View full abstractDownload PDF (744K) -
Hideki YOSHIKAWA, Kazuhiro SATO, Kunio YOSHIDA, Koichi KOBAYASHI, Taic ...1987 Volume 36 Issue 11 Pages 755-760
Published: November 05, 1987
Released on J-STAGE: November 18, 2010
JOURNAL FREE ACCESSAccelerator Mass Spectroscopy (AMS) is considered to be the most effective method for the determination of the 14C content in a minute amount of carbon, and used for carbon dating of archeological and geochemical samples. At the Tamdem Van de Graff at the University of Tokyo two sample preparation methods are currently used and the method of direct carbonization of organic material can give dating of as old as sixty thousand years. However, dating is limited to 35 thousand years for the method that requires the reduction of CO2 into amorphous carbon, possibly due to contamination by the modern carbon. In the present work, in order to improve the latter method, the amount of modern carbon contamination was determined for various chmicals used in the sample preparation; namely, the carbon content in the metallic Mg used as the reducing agent was determined by charged particle activation analysis, and the 14C contents in organic solvents used for washing the glass ware, in the rotary pump oil, and in the metallic Mg were determined by AMS. Based on the knowledge of those results, a greaseless vacuum line with several cold traps was newly built for the sample preparation, and the dating limit of 46 thousand years could be achieved by use of the highly pure Mg that contained 6 ppm C.View full abstractDownload PDF (1018K) -
Yuzi TAKAYAMA, Tomoo YAMAGUCHI, Satoshi KAWAI1987 Volume 36 Issue 11 Pages 761-765
Published: November 05, 1987
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSA method is described for trace analysis in capillary GC using a mixture of 100 ppb n-alkanes (C14C26) in hexane as a sample solution. An gas chromatograph equipped with a FID was connected to a Nippon Chromato On-column Processor (an instrument having an injector and a precolumn capable of being rapidly heated independently of the oven). A precolumn, Ras 100 (a deactivated stainless steel tube, 1.0 mm i. d. × 200 cm) was connected to an analytical column, Rascot LB OV-1 (0.8 mm i. d. ×25 m, a deactivated stainless steel column coated with OV-1, depth of film: 0.53 μm) by a metal joint. One hundred μl of the sample solution was taken in a syringe with a long needle (0.5 mm o. d.×15 cm). After the sample solution was slowly introduced into the precolumn being kept at room temperature, the precolumn was rapidly heated to about 200 °C by applying electric current. The heavy and the volatile solutes were retained just at the head of the analytical column by cold trapping and by solvent effect, respectively. When the peak of the solvent was almost eluted, the oven temperature was increased from 50°C to 250 °C at a rate of 5 °C/min. Nitrogen was used as a carrier gas at an average linear velocity of 35 cm/s. The effects of injection volume of sample and the injection time on the peak shape and band broadening were examined. Thirty seconds were adequate for an injection of 100 μl of sample solution and 3 min was for that of 500μ1. The reproducibility of the procedure was calculated to be less than 2.2% of relative standard deviation from four replicate determinations on directly injected 100 μl of 100 ppb each of n-alkanes. The method has, therefore, been shown to be an effective means for the trace analysis in GC.View full abstractDownload PDF (736K) -
Yasuyuki HOSHIKA, Ninzo MURAYAMA, Giichi MUTO1987 Volume 36 Issue 11 Pages 766-771
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe pretreatment for GC of lower aliphatic polysulfides was investigated using a Tenax-GC precolumn (16 cm × 4 mm i.d., glass, 60/80 mesh). The sample was directly collected in the Tenax-GC precolumn by adsorption at room temperature. Then pre-separation process in the gas phase under nitrogen carrier gas flow was carried out to eliminate the sulfur compounds with lower to middle boiling points in the sample that were condensed on the Tenax-GC adsorbent. The Tenax-GC precolumn, which collected sample was purged with nitrogen carrier gas flow of 0.2 to 0.375 l/min at 25 °C. This pre-separation in the gas phase was necessary for the elimination of the large amounts of lower to middle boiling sulfur compounds, which interfered for the determination of the trace amount of lower aliphatic polysulfides by flame photometric detector-GC detection. The break through volume (10% loss) of several sulfur compounds was as follows: 4.5 l for thiophene, 25 l for dimethyl disulfide, 28 l for tetrahydrothiophene, 450 l for diethyl disulfide, 600 l for dimethyl trisulfide, respectively. Therefore, the lower aliphatic polysulfides were quantitatively recovered from the Tenax-GC precolumn in the pre-separation process in the gas phase. The maximum time for the pre-separation was less than 60 min.View full abstractDownload PDF (744K) -
Junichi GOTO, Toshiyuki CHIKAI, Kanako MAKIUCHI, Toshio NAMBARA1987 Volume 36 Issue 11 Pages 772-775
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSComparative studies on solid-phase extraction for the determination of bile acids in biological fluids were carried out. A test sample containing various amounts of bile acids was passed through a column of Amberlite XAD-2 resin or cartridge packed with octadecylsilyl (ODS) bonded silica, i.e., Bond Elut and Sep-Pak C18. Bile acids were eluted, derivatized with 1-anthroyl nitrile through their 3α-hydroxyl groups and determined by HPLC with fluorescence detection. When 2.0 nmol each of bile acids were applied to the Amberlite XAD-2 column, the recovery rates were insufficient, in particular for conjugated bile acids. On the other hand, when more than 20 nmol each of bile acids were loaded, the satisfactory results were obtained. The use of Bond Elut and Sep-Pak C18 cartridges provided almost the quantitative recovery of bile acids, even when 0.2 nmol each of bile acids were applied. It has proved that Amberlite XAD-2 resin is applicable to bile specimens for solid-phase extraction, while the cartridge packed with ODS bonded silica is also useful for serum sample preparation.View full abstractDownload PDF (589K) -
Fumio IINUMA, Masayoshi TABARA, Mitsuo WATANABE1987 Volume 36 Issue 11 Pages 776-781
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe recovery of 3-hydroxyanthranilic acid (3-OHAA) in biological fluids was found to be greatly enhanced by the addition of 2-mercaptoethanol. This finding was successfully applied to improve the assay procedure of 3-OHAA in urine and serum (or plasma). The procedure for serum was as follows. To 0.5 ml of serum was added 0.5 ml of distilled water, 0.05 ml of 2-mercaptoethanol, 6 g of sodium chloride and 5 ml of citrate buffer (pH 3), and the mixture was then shaken with 3 ml of diethylether for 3 times. The extract was evaporated to dryness under reduced pressure, and the residue was dissolved in 0.25 ml of mobile phase solvent. The fluorescence intensity of 3-OHAA excited at 320 nm was measured at 420 nm. The calibration curves for 3-OHAA showed a linear relation in the range of 50 pg to 1 ng. The relative standard deviation at 800 pg was 3.7% (n = 10). In this procedure, the recovery of 3-OHAA in serum was found to be 98.8±4.1% (n= 7, 4 ng). 3-OHAA concentration in serum of animals were 2.57.9 (human), 3.3 (rabbit), 1.2 (rat) and 5.9 ng/ml (dog). The technique permits measurement of 3-OHAA in biological fluids, such as serum, plasma and urine, with sample volume of 0.5 ml. This method is useful for simple, specific and sensitive detection of 3-OHAA, and it is easily adapted to routine analysis of 3-OHAA.View full abstractDownload PDF (824K) -
Clinical Analysis on Steroids. 39Kazuhiro WATANABE, Takashi SATOH, Itsuo YOSHIZAWA1987 Volume 36 Issue 11 Pages 782-786
Published: November 05, 1987
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSFor measuring an aromatization of testosterone sulfate (TS) by human placental microsomes, tritium waterrelease method using (1β, 2β-3H)-TS as a substrate was applied. The procedure is as follows: To the supernatant of the incubation mixture was added a suspension of dextran-coated charcoal, followed by centrifugation to remove an unreacted substrate. The supernatant obtained was passed through Sep-Pak C18-cartridge, and the tritium contents of the eluates were determined. The tritium water generated could be determined quantitatively by complete elimination of the radioactive substrate remained. The detection limit calculated as estradiol 17-sulfate (ES) formation was about 50 fmol per one incubation test tube (3 ml). The results obtained for the conversion of TS to ES by the present method agreed well with those by reverse isotope dilution method. The proposed method is so rapid, simple, accurate and sensitive; it may be utilized for study on the aromatization of TS by such estrogenproducing organs as ovary and testis.View full abstractDownload PDF (667K) -
Yoshiko TASHIRO, Akira SUZUKI, Kosei NODA, Hideyo NOGUCHI1987 Volume 36 Issue 11 Pages 787-791
Published: November 05, 1987
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSA method for the determination of FK565, an immunostimulative acylpeptide, in plasma by HPLC was developed to investigate its metabolic fate in experimental animals. The rat or mouse plasma was deproteinized with 6% trichloroacetic acid and the supernatant was applied onto a Bond Elut® C18 cartridge. FK565 was eluted with a mobile phase consisting of acetonitrile-20 mM phosphate buffer, pH 2.5 (21 : 79). FK565 was separated on the reversed phase C18 column (TSK-Gel LS-410 ODS Sil, 150 mm × 4 mm i.d.) and detected fluorometrically after postcolumn derivatization with ο-phthalaldehyde in the presence of 2-mercaptoethanol. Maximum fluorescence intensity, with a reagent flow rate of 1.0 ml/min was obtained at the mobile phase flow rate of 0.5 ml/min. The relative standard deviation of reproducibility for the method was less than 2.3% in rat and mouse plasma, when 100 μl of the plasma spiked with 10 ng of FK565 was analyzed three times. This method did not need a special internal standard. The lowest limits of determination for the rat and mouse plasma were 50 ng/ml and 20 ng/ml, respectively. This method permitted the measurement of pharmacokinetic profile of FK565 in rat and mouse plasma.View full abstractDownload PDF (609K) -
Mitsuya SHIMODA, Koji HIRANO, Yutaka OSAJIMA1987 Volume 36 Issue 11 Pages 792-798
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA concentration method of volatile compounds onto a small column packed with porous polymer beads was proposed for foods, especially liquor. One liter of various flavor solutions were passed through the column packed with 5 ml of porous polymer beads (5080 mesh) and the adsorbed volatile compounds were eluted with 20 ml of ethyl ether. 1) Among six kinds of beads, Porapak Q and Chromosorb 106 gave the best recoveries of volatile compounds from the 20% ethanol solution. 2) Alcohols, aldehydes and esters with carbon atoms more than 6 were recovered quantitatively from the ethanol-free solution. 3) In 20% ethanol sloution, the recoveries of hexanol, hexanal and ethylbutyrate decreased to 63, 86, 89%, respectively but the compounds with carbon atoms more than 8 were recovered completely. 4) When the solution contained ethanol 30% or above, the recoveries were greatly decreased. Therefore, a dilution with water and/or salting out technique were required prior to the treatment. 5) The recoveries were little affected by addition of surface-active agents. 6) When the volatile compounds were extracted from the column with ethyl ether of four-fold volume of resin, the recoveries were above 97% for all compounds. The residuals were completely extracted by an additional extract. The concentrations of volatile compounds from a commercial beer were done in order to compare the present method with a simultaneous distillationextraction (SDE) method under reduced pressure. As a results, the present method gave excellent recoveries in not only high boiling compounds but also acidic and phenolic, and basic compounds. The mean reproducibility (n=5) of arbitrarily selected 12 peaks was 14.0% for the present method and 37.9% for SDE method as a relative standard deviation.View full abstractDownload PDF (1047K) -
Jun-ichi ITOH, Masashi KOMATA, Hiroshi OKA1987 Volume 36 Issue 11 Pages 799-801
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSPhotochemical decomposition and acid digestion followed by concentration of copper with Chelex 100 chelating resin were studied. Standard 6.13 ppb copper samples containing 4 ppm of humic acid or EDTA adjusted at pH 8 were used for digestion and recovery test. Huminc acid or EDTA in the sample was completely decomposed by UV irradiation for over 20 min at pH 1 and copper was quantitatively recovered. On the other hand, the acid digestion by boiling for 3 h at pH 1 gave 90% and 0% of the recovery of copper from humic acid solution and EDTA solution, respectively. When the humic acid solution was not treated, the recovery was 14.5%. The recommended procedure was as follows. Sample (400 ml) adjusted at pH 1 with 1 M nitric acid was photo-oxidized by UV irradiation for 30 min. Copper was concentrated on chelating resin (Chelex 100) at pH 5 and eluted with 10 ml of 1 M nitric acid. Copper in the effluent was determined by spectrophotometry with tetrakis (4-N-trimethylaminophenyl) porphine. The relative standerd deviation for the standerd sample was 3.65% (n=7). The present method was applied to the determination of copper in the seawater.View full abstractDownload PDF (563K) -
Eiji AOYAMA, Terumichi NAKAGAWA, Noriko HASEGAWA, Tomoo TANAKA, Masahi ...1987 Volume 36 Issue 11 Pages 801-803
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA preconcentration method using a micro column packed with anion-exchange resin loaded with Bismuthiol-II sulfonic acid (Bis-IIS) has been developed for the determination of trace level of Se. Selenium(IV) in 0.5 M HCl solution was collected on the column, based on the formation of selenotrisulfide (-S-Se-S-) linkage with Bis-IIS. Selenium (IV) collected on the resin was eluted with penicillamine solution as penicillamine selenotrisulfide(PenSTS). PenSTS was converted to 7-nitrobenzo-2, 1, 3-oxadiazole (NBD) derivative, and Se was determined as NBD-PenSTS by HPLC with fluorometric detection. The use of a micro column was effective in the preconcentration of Se of small scale procedure to shorten the time required for the analysis.View full abstractDownload PDF (463K) -
Chiyo MATSUBARA, Kiyoko TAKAMURA1987 Volume 36 Issue 11 Pages 803-805
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA simple method for the determination of trace amount of arsenic trihydride in gas phase was proposed. Arsenic trihydride was absorbed in sodium hypobromite and oxidized to arsenate. Molybdoarsenate-Malachite Green aggregate formed by Mo-MG reagent (mixed solution of ammonium molybdate and Malachite Green) was selectively collected on a nitrocellulose membrane filter (3μm pore size). The aggregate was dissolved in a small volume of methylcellosolve together with the membrane filter. The absorbance (λ: 627 nm) was proportional to the amount of arsenic trihydride. The molar absorptivity of aggregate in methylcellosolve is 2.6 × 105 M-1 cm-1. The method was applied to the determination of arsenic trihydride at 10 ng level in gas phase.View full abstractDownload PDF (415K) -
Hiroshi KAWAMOTO, Hideo AKAIWA1987 Volume 36 Issue 11 Pages 805-808
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe spectrophotometric determination of trace phosphate ion in natural water after enrichment by coprecipitation with calcium carbonate has been studied. Coprecipitation procedure was as follows: To a 500 cm3 of water sample, each 10 cm3 of 2 M (M=mol dm-3) sodium hydroxide and 2 M sodium carbonate and then 10 cm3 of 2 M calcium chloride were added with continuous agitation. The resulting precipitation was separated with a 0.45 μmφ membrane filter, and dissolved in 8.0 cm3 of 6 M hydrochloric acid. Phosphate ion in the solution was determined spectrophotometrically with the conventional Molybdenum Blue method. Enrichment factor obtained by the established method was 50, and more than 9.6 μg dm-3 of PO43- in a water sample, which corresponds to the absorbance 0.1 (1 cm cell), could be determined accurately.View full abstractDownload PDF (686K) -
Isao SUZUKI, Tsutomu YAMASHITA1987 Volume 36 Issue 11 Pages 808-811
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSNew method for identification of very small precipitates in an extruded Al alloy bar is discussed in this paper. Precipitates are corrected using selectively etching of Al matrix phases by 1 M NaOH solution at room temperature for 30 min. Micro focused X-ray diffractometer with curved position sensitive proportional counter was used to identify these very small precipitates. The precipitates usually remain on the specimen surface as granule shape about 25μm in diameter, and then they are scraped up and held on a glass rod tip with liquid adhesive, subjected to X-Ray diffraction analysis.View full abstractDownload PDF (951K) -
Akira TANAKA, You-ichi IMASAKA, Kayo HAYASHI, Toshio DEGUCHI1987 Volume 36 Issue 11 Pages 811-814
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSSeparation of iodide and thiocyanate from lysozyme by gel filtration chromatography is described. Mutual separation of iodide and thiocyanate is also described. The mixed sample (100 ppm lysozyme, 0.2 μM I-, 20μM SCN-, 200 μl) has been eluted from gel filtration column (Sephadex LH-20 or G-20, 25 cm × 8 mm i.d.) with 0.3 M sodium chloride, 1.3 ml/min. Eluted species have been fluorometrically determined by catalytic reaction based on redox reaction between Ce (IV) and As(III) in FIA system. Iodide and thiocyanate were eluted at 13 min and 17 min, respectively. Calibration graphs are straight lines through origin. The determination ranges were 30 nM4μM I- and 3 μM20 μM SCN-. Component species of human urine did not interfere. Combination of LH-20 column and ion chromatographic column is also described.View full abstractDownload PDF (625K) -
Hiroyuki WAKABAYASHI, Kenichi WATANABE, Akira SHIBATA, Susumu YAMATO, ...1987 Volume 36 Issue 11 Pages 814-817
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA modified sample clean-up method for the HPLC of catecholamines (CA) in biological samples was proposed. At the adsorption procedure the loss of alumina was neglected by placing a disk filter on the bottom disk in the Mini column, and also a top filter on the surface of the sample solution. Plasma and heart extract were adsorbed onto alumina in Sepacol Mini tube. In order to obtain a constant and efficient adsorption of CA, the authors introduced the improved rotary mixer for the rotation of alumina column. By mixing the CA sample solution and alumina with rotary mixer, the recovery and reproducibility of CA were considerably improved comparing with the conventional method. HPLC with the clean-up procedure was applied to the determination of CA in human plasma and rat heart. The utility of the proposed clean-up method of CA (norepinephrine, epinephrine and dopamine) was sufficiently recognized.View full abstractDownload PDF (719K) -
Yukio HIRAI, Katsumaro TOMOKUNI1987 Volume 36 Issue 11 Pages 817-819
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA simple sample-pretreatment method was developed for GC/MS analysis of chlordanes residues in river sediments. The method is composed of three steps, i.e., (1) extraction in a 10-ml test tube, (2) clean-up with a micro silica gel column, and (3) concentration by micro-evaporation. Both clean-up and concentration were carried out using a capillary pasteur pipette. The chlordanes was extracted from 1 g of the sediment and was concentrated to 2030 μl as a sample solution. The contents was determined by injecting a sample solution onto GC/MS. The total concentration of trans-γ-chlordane and cis-α-chlordane was determined by selected ion monitoring (m/z 375). The recovery of the standard trans-chlordane was estimated to be about 50%. The detection limit of the trans-chlordane was 3 pg. The present method is enough sensitive to detect ppt to ppb levels of chlordanes residues in river sediments.View full abstractDownload PDF (543K) -
Preconcentration of cadmium(II) by synergistic extraction with dithizone and tributylphosphine oxideYasoo ITOH, Hiroshi KAWAMOTO, Hideo AKAIWA1987 Volume 36 Issue 11 Pages T119-T122
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA simple preconcentration method for Cd(II) in natural waters based on the synergistic extraction with dithizone and tributylphosphine oxide (TBPO) is proposed. The recommended preconcentration procedure is as follows: to 300 cm3 of water sample in a 500-cm3 separatory funnel is added 10 cm3 of acetate buffer solution to adjust the pH around 4. Then 3 cm3 of dithizone-TBPO solution in carbon tetrachloride (7.8 × 10-4 and 0.1 mol dm-3, respectively) is added, and the mixture is vigorously shaken for 20 min. After the phases are allowed to separate, the organic phase obtained is used for analysis. Using this method, Cd (II) in natural waters with levels of ng dm-3 range could be determined by the graphite furnace AAS.View full abstractDownload PDF (486K) -
Masataka NISHIKAWA, Satoru KANAMORI, Nobuko KANAMORI, Tsuguo MIZOGUCHI1987 Volume 36 Issue 11 Pages T123-T128
Published: November 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSAndersen sampler is used advantageously to collect sizable amounts of aerosol samples divided into several well-defined size fractions. There, the selection of the collecting media which catch and keep aerosol particles is of considerable importance. From the view point of chemical analyses, it is required for the media to have impurity levels as low as possible. In the present study, the impurity levels of twenty elements in fourteen kinds of collecting media were investigated by ICP-AES. The extraction tests of these elements from each media into distilled water and 1 M-HNO3 are carried out with ultra-sonic agitation for 10 min. The total contents of these elements are also determined after acid digestion. The two filters of glass fiber and quartz fiber have high levels of impurities which are not able to be washed out into 1 M-HNO3. Membrane filters have low impurities and most of them are able to be washed out in distilled water. No element is detected by ICP-AES in teflon filter, and polyvinylidene chloride and polyethylene films. As the polyethylene media is lighter in weight and easier in handling than the others, the polyethylene thin film is recommended as the most favorable collecting media for elemental analysis of atmospheric aerosols by an Andersen sampler.View full abstractDownload PDF (830K)
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