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Mizuo MAEDA, Yosuke OHKURA
1989 Volume 5 Issue 4 Pages
369
Published: 1989
Released on J-STAGE: July 27, 2007
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Yosuke OHKURA
1989 Volume 5 Issue 4 Pages
371-388
Published: August 10, 1989
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Pre- and postcolumn derivatization methods employing recently-developed bifunctional fluorogenic reagents for high performance liquid chromatography have been demonstrated to be successful regarding both sensitivity and selectivity in the determination of bioactive substances and their related enzymes. The reagents were designed mostly based on the principle that vicinal or geminal, homo- or hetero-bifunctional (diamino, amino-imino, amino-sulfhydryl or amino-hydroxyl) compounds react with 1, 2-dioxo compounds (1, 2-ketols, glyoxals, 1, 2-diketones or 1, 2-quinones) or monooxo compounds (aldehydes) to yield fluorescent cyclic products. These reagents have been introduced into the quantification process of diverse bioactive substances in biological samples at the femtomole level.
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Hideo IMAI, Gen TAMAI, Tsutomu MASUJIMA, Ikue MORITA-WADA
1989 Volume 5 Issue 4 Pages
389-393
Published: August 10, 1989
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The usability of column-switching techniques of high performance liquid chromatography is reviewed with special interest given to the enrichment and cleanup of biological samples. In Section 2, band broadening and a fully automated operation system are especially noted. In Sections 3 and 4, it is emphasized that the recovery of on-line solid extraction in a precolumn is quantitative (100%), depending upon the combination of the stationary phase and the mobile phase. In Section 5, are elucidated the deproteinization and recovery from protein-bound entities by a size exclusion coupled with internal-surface reversed-phase techniques or by hydrophobic interaction. These methods are extensively applied to the biological samples, such as whole blood and tissue homogenates, which contain minute particles, by using a large-bore endfitting filter for the precolumn.
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Yoshihide NOZAKI, Teruko IMAI, Keiko GOTO, Yorishige IMAMURA, Masaki O ...
1989 Volume 5 Issue 4 Pages
395-397
Published: August 10, 1989
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A simple and rapid high performance liquid chromatographic method has been developed for the determination of befunolol (BF) and its major metabolite, dihydrobefunolol (DBF), in rabbit plasma. The drug and its metabolite were simultaneously detected with a dual-wavelength UV detector to optimize sensitivity. The detection limits were 1ng/ml for BF and 5ng/ml for DBF. This method was shown to be practically applicable to pharmacokinetic studies of BF.
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Junichi GOTO, Yutaka SAISHO, Toshio NAMBARA
1989 Volume 5 Issue 4 Pages
399-402
Published: August 10, 1989
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Highly sensitive and moderately reactive derivatization reagents having an anthracene moiety as a fluorophore and carboxylic acid hydrazide of
O-aralkylhydroxylamine as a reacting group toward the carbonyl function have been developed. The derivatization reagents, anthracene-1- and 2-carboxylic acid hydrazides and
O--(1-, 2- and 9-anthrylmethyl)-hydroxylamines, were readily prepared from the corresponding anthracenecarboxylic acids in several steps. The carbonyl compounds underwent facile derivatization with these reagents under mild conditions. The resulting hydrazones and oximes were highly responsive to a fluorescence detector in high performance liquid chromatography, the limits of detection being 50 and 20fmol, respectively.
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Mikio ZINBO, C. E. HUNTER, L. M. SKEWES, Dennis SCHUETZLE
1989 Volume 5 Issue 4 Pages
403-409
Published: August 10, 1989
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A method for determining the contribution of lubricating oil and fuel to particulates emitted from diesel engines is described. Methylene chloride extracts of the particulates were separated by silica gel fractionation using hexane, methylene chloride, acetone and methanol. The molecular weight distribution of each fraction was determined using size exclusion chromatography. The speciation of diesel particles into unoxidized oil, oxidized oil, unoxidized fuel and oxidized fuel was determined systematically for a diesel engine modified over a period of more than a year. These modifications significantly affected the total extractable material (12.6-72.3%) and distribution of oil and fuel components. Engine oil was consistently found to be the major contributor to the extractable material, varying from 10 to 60% of the total particulates emitted.
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Michael G. SCHWENDINGER, Bernd M. RODE
1989 Volume 5 Issue 4 Pages
411-414
Published: August 10, 1989
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Peptide synthesis from amino acids has been shown to occur in aqueous solutions at high concentrations of sodium chloride and in the presence of Cu(II) after several days at 85°C, under nitrogen or air as well. Di- and tripeptides could be obtained in a series of experiments which have yet to be optimized. However, these experiments have proved the principle applicability of a model which is based on the structural features of concentrated aqueous NaCl solutions and evidence of catalytic effects in peptide condensation reactions exerted by di- and trivalent metal ions. Among the ions of Mg, Ca, Cr, Mn, Co, Ni, Fe, Cu, Zn and Cd, only copper was found to be active under these conditions. This leads to new aspects for possible prebiotic peptide syntheses based on a very simple system of only water, amino acids and mineral salts.
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A. B. FARAG, A. M. EI-WAKIL, M. S. EI-SHAHAWI, M. MASHALY
1989 Volume 5 Issue 4 Pages
415-417
Published: August 10, 1989
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Polyurethane foam, polyether type, has been recommended as an efficient collector in separating and concentrating some selected chlorinated insecticides and polychlorinated biphenyls from aqueous media. In the present work, the collection and recovery of Baythroid, CME-134 and the ethyl derivative of Sumicidine insecticides from water were examined using static and columns foam extraction modes. The extraction isotherm of the three insecticides tested exhibited a first order behavior in the low concentration. Insecticides were successfully retained on the foam column at reasonable flow rates. The collected insecticides were recovered from the foam material with 100 cm
3 acetone in a Soxhlet extractor, and their concentrations were then measured spectrophotometrically. The application of the developed method for the extraction of the above mentioned insecticides in Nile river water has been evaluated.
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Kunihiro WATANABE, Massoud HOJJATIE, Shinichi IMAI, Shinsuke KOBAYASHI
1989 Volume 5 Issue 4 Pages
419-423
Published: August 10, 1989
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A new sulfur containing bidentate ligand 2
N-(2-mercaptophenyl)-1, 2, 3-benzothiadiazoline (MBDT) was synthesized by the Sandmeyer/Azo coupling reaction. This reagent reacts selectively with palladium to form extractable complexes which are different from those complexes prepared by a direct addition of the reagent. The spectrum of the complex is red shifted from that of the free reagent. The extractability of the Pd-MBTD complex is affected in the presence of some anions, such as Br
-, l
- and SCN
-, but enhanced in presence of Cl
-. The dissociation constants and the distribution constants for the palladium ions with MBTD were evaluated.
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Akira UCHIUMI, Hisashi TANAKA
1989 Volume 5 Issue 4 Pages
425-428
Published: August 10, 1989
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Chelating resins have been prepared by introducing formazane derivatives with acid groups (X) to polyacrolein (X=COOH, OH, AsO
3H
2etc.). For the resins, the distribution coefficients (
Kd) of metal ions and their pH dependency, and exchange capacity have bee examined. The resins show high selectivity to Cd
2+, Zn
2+ and Cu
2+, log
Kd being 4.20-5.54 for Cd
2+, 4.03-4.70 for Cu
2+ and 3.57-4.50 for Zn
2+. The exchange capacities (meq/g) are 1.63-2.42 for Cu
2+, 1.70-2.41 for Cd
2+ and 1.73-2.41 for Zn
2+.
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Tamio KAMIDATE, Tadashi SEGAWA, Hiroto WATANABE, Katsumi YAMAGUCHI
1989 Volume 5 Issue 4 Pages
429-433
Published: August 10, 1989
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A continuous flow method was developed for the determination of chromium (VI) with lophine chemiluminescence. Activated alumina was effectively used for separation of Cr(VI) from metal ions such as Cu(II) and Cr(III) which interfered with the determination. The detection limit was 20 ng cm
-3 without preconcentration and the relative standard deviation was 3% at 50 ng cm
-3 of Cr(VI). The method was applied to the determination of Cr(VI) in water samples.
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Hiroshi KAWAGUCHI, Tomokazu TANAKA, Masakazu TANABE, Atsushi MIZUIKE
1989 Volume 5 Issue 4 Pages
435-438
Published: August 10, 1989
Released on J-STAGE: June 30, 2006
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A water-cooled torch can reduce the outer gas flow rate down to 6 l/min in inductively coupled plasma mass spectrometry. However, the sensitivity is deteriorated by 40 to 50%. Doubly charged and oxide ions of analytes as well as copper ions are increased with water cooling. The copper ions originate from the sampling orifice of the mass spectrometer. The increases of the doubly charged and of the copper ions are assumed to be due to the enhancement of the secondary discharge at the sampling orifice, which is caused by the increased capacitive coupling of the rf power between the load coil and the plasma.
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S. BEKTAS, T. BALKIS, S. AKMAN
1989 Volume 5 Issue 4 Pages
439-444
Published: August 10, 1989
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The effects of NaCl, CaCl
2 and MgCl
2 salts on the atomization process of Cd and Mn elements in a graphite furnace were investigated. The absorbance signals as a function of pre-atomization temperatures were obtained for the analyte, matrix and the analyte in the matrix. In addition, the matrix and the analyte were injected separately on the graphite surface. The comparison of the obtained data with the thermochemical and physical properties of the matrix and the analyte led to conclusions about the interference mechanisms. The type of interference that affects the sensitivity of the analyte depends on the thermal behavior of the matrix before and during the atomization of the element in the graphite furnace. If chlorine atoms are formed by the decomposition of the matrix at temperatures close to the atomization temperature of the element, formation of a metal chloride in the gas phase is responsible from the decrease in the sensitivity. On the other hand, when the matrix is present as a solid or liquid in the graphite furnace while the element atomizes, the occlusion of the element in the matrix occurs. The change of the sensitivity depends on the physical and chemical nature of the analyte and the matrix.
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Kuniyuki KITAGAWA, Tetsuya TAKEUCHI, Masaaki YANAGISAWA
1989 Volume 5 Issue 4 Pages
445-448
Published: August 10, 1989
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The basic characteristics of a separative column atomizer (SCA) were studied in conjunction with the retention of atomic vapors of Hg, Cd and Pb. The column atomizer consists of an alumina tube heated at 800-1400°C, which is packed with graphite granules coated with Au or Pt, or mixed with Sn powder. Different retention characteristics and peak broadening were observed for different packings. The retention of atomic vapor through the SCA might be useful for the separation of coexisting elements and the removal of their interference.
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Toshiko NASU, Setsuko KANEKO
1989 Volume 5 Issue 4 Pages
449-452
Published: August 10, 1989
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A sensitive and accurate spectrophotometric method is described for the determination of phosphate in natural water using Rhodamine B. The ion pair of molybdophosphate with Rhodamine B is floated at the phase boundary between an ethyl ether phase and an aqueous phase: the aqueous phase comprises 1.0 mol dm
-3 nitric acid, 33 mmol dm
-3 sodium molybdate and 20μmol dm
-3 Rhodamine B. The small amount of excess Rhodamine B extracted into ethyl ether is removed by washing the organic phase with 25 cm
3 water. The floated ion pair is dissolved by adding methanol into the ethyl ether phase after discarding the aqueous phase. The calibration curve for phosphate is linear up to 1.0μg of phosphorus with the correlation coefficient of 0.999. The apparent molar absorptivity of phosphate was 4.1×10
-5 dm
3mol
-1cm
-1 at 555 nm; the relative standard deviation was 2.0% for 1.0μg of phosphorus (10 determinations). Arsenate causes positive error, while no ions commonly existing in natural water, except large amounts of silicate ions, interfere with the determination of phosphate. The proposed method was applied to the determination of phosphate-phosphorus in some samples of natural water; satisfactory results were obtained.
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Werner E. MORF, René BLIGGENSDORFER, Wilhelm SIMON
1989 Volume 5 Issue 4 Pages
453-458
Published: August 10, 1989
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To investigate the influence of a covalent interconnection of ionophore subunits (e.g. to obtain so-called bis(crown) compounds) on the ion selectivity of corresponding electrodes, a theoretical treatment of the underlying chelate effect is presented. Entropic contributions given by standard-state and statistical terms, as well as enthalpic contributions resulting from a ligand preorganization, are discussed. The latter contributions are shown to reflect the intrinsic chelate effect, as redefined by Frausto da Silva, and to be decisive for a possible enhancement of the potentiometric selectivity of ion selective electrodes based on such ionophores. An experimental study of the ion selectivities as well as of the alkali-ion complex stabilities of covalently bridged and non-bridged ligands with Li
+ selectivity uncovers no significant effects that could be attributed to a preorganization of these ligands.
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Yuzuru HAYASHI, Rieko MATSUDA
1989 Volume 5 Issue 4 Pages
459-464
Published: August 10, 1989
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An optimization method of detection wavelengths in column chromatography is described on the basis of the information measure FUMI (FUnction of Mutual Information) which denotes the mutual information of chromatography. Functions required as quality criteria for success in the wavelength optimization comprise the total mutual information Φ (FUMI), the information loss δΦ and the information variation of individual peaks ΔΦ. The variation ΔΦ is defined by slight modification of FUMI and is shown to be indispensable for the wavelength optimization. An experimenatal design for column chromatographic determination of antipyretics mixtures, previously proposed, is evaluated information-theoretically in terms of the three functions.
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Susumu ICHINOKI, Mitsuru YAMAZAKI
1989 Volume 5 Issue 4 Pages
465-469
Published: August 10, 1989
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Copper and iron in standard reference materials of the National Bureau of Standards (NBS) have been simultaneously determined. Bovine liver was ashed with a mixture of HNO
3-HClO
4, and Tomato Leaves with HNO
3-HClO
4-HF. Copper and iron in biological samples were extracted into organic phases of small volume as acetylacetone(AA) chelates. The chelates were then separated on a COSMOSIL 5C
18 column with an eluent of CH
3OH-H
2O-CH
2Cl
2-AA (59:37:4:0.5) and detected at 330 nm. This method permitted the separation and determination of copper, iron and palladium. Interference from foreign ions was investigated with various cations, anions, acids, reductants and oxidants. The μg/g levels of copper and iron in samples were determined, the results showing good agreement with the certified NBS values.
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Suwaru HOSHI, Yoshimasa TANAKA, Sadanobu INOUE, Mutsuya MATSUBARA
1989 Volume 5 Issue 4 Pages
471-474
Published: August 10, 1989
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An adsorption-elution and spectrophotometric method using chitin was proposed for the preconcentration and determination of copper. Copper is collected as its neocuproine (neoc) complex on a column of chitin in the presence of tetraphenylborate as a counter ion. The copper-neoc complex retained on chitin is eluted with a mixture of acetone and a 1 mol dm
-3 acetic acid solution (8:2, v/v) as an eluent, and the absorbance of the eluent is measured at 453 nm. Beer′s law is obeyed over a concentration range of 1.9 to 19.1. μg in 10cm
3 of eluent. Al, Fe(II), Fe(III), Co, Ni, Zn, Cd and Pd do not interfere with the determination for concentrations up to 500-times (Mg, Ca and Mn up to 1000-times) that of copper in the presence of EDTA as a masking agent. Common inorganic anions also do not interfere for concentrations up to 10000-times that of copper. The proposed method can be applied to the determination of copper in tap water and standard samples.
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Kunihiko AKATSUKA, Naoki NOBUYAMA, Ikuo ATSUYA
1989 Volume 5 Issue 4 Pages
475-479
Published: August 10, 1989
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An enrichment procedure for cobalt is described which is based on precipitating this element with 8-quinolinol and a carrier metal ion, filtering the precipitates and then analyzing them directly by electrothermal atomic absorption spectrometry (EAAS). Submicrogram amounts of the element were coprecipitated quantitatively with magnesium 8-quinolinate from 100cm
3 of aqueous solutions of pH 9.5. Quantitative recoveries of the metal from aqueous solutions ranging from 200 to 500 cm
3 were also possible. Humic material and organic acids do not interfere with the recovery efficiencies of the method. This method was applied to a tap and river water samples. Using this method, cobalt(II) in natural water at levels below μg dm
-3 range could be determined by EAAS using a solid-sampling technique.
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Yuzo TAMARI, Nobuki YAMAMOTO, Haruo TSUJI, Yuzuru KUSAKA
1989 Volume 5 Issue 4 Pages
481-484
Published: August 10, 1989
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A new coprecipitation method for the spectrophotometry of arsenic(III) and arsenic(V) in groundwater has been developed. Arsenic(III) and arsenic(V) were coprecipitated with thorium(IV) hydroxide from 1000 ml of groundwater at pH 9. The precipitate was centrifuged and then dissolved with hydrochloric acid. Arsenic(III) was spectrophotometrically determined by the usual silver diethylditiocarbamate (Ag-DDTC) method after generating the arsenic to arsine with sodium tetrahydroborate under masking the thorium with EDTA-NaF at pH 6. From another portion of the same groundwater, both arsenic(III) and arsenic(V) were determined by the Ag-DDTC method after reducing all the arsenic to arsine with sodium tetrahydroborate at pH less than 1 in the presence of the EDTA-NaF. The concentration of arsenic(V) was obtained by subtracting that of arsenic(III) from the total for arsenic.
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Masahiro KAWAHARA, Hiroshi NAKAMURA, Terumi NAKAJIMA
1989 Volume 5 Issue 4 Pages
485-486
Published: 1989
Released on J-STAGE: July 27, 2007
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Qiuwen ZHAO, Hiroko WADA
1989 Volume 5 Issue 4 Pages
487-488
Published: August 10, 1989
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Toshio FURUYA, Shigeo FUJITA, Takashi FUJIKURA
1989 Volume 5 Issue 4 Pages
489-490
Published: August 10, 1989
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Naokazu SUGIYAMA, Kin-ichi SAITO, Motoaki GOTO, Hideo MIZU, Kenkichi T ...
1989 Volume 5 Issue 4 Pages
491-492
Published: August 10, 1989
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