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Volume 45, Issue 2
Displaying 1-13 of 13 articles from this issue
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Makoto MIZOGUCHI, Munetaka ISHIYAMA, Masanobu SHIGA, Kazumi SASAMOTO1996 Volume 45 Issue 2 Pages 111-124
Published: February 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSEnzymatic methods for determining biogenic compounds are a key technology in quantification of various analytes of clinical interest in the biomatrix and have found wide application in clinical diagnosis due to their high selectivity and rapidity. The enzymes employed for this purpose are primarily oxidases and dehydrogenases. Upon reacting with target compounds, these enzymes produce hydrogen peroxide or NAD(P)H, amounts of which are then determined by using oxidative or reductive chromogenic reagents, respectively. In chromogenic reagents, the following properties are desirable: 1) a long absorption wavelength, 2) strong resistance to interferences caused by various compounds (such as bilirubin) in the biomatrix, 3) stability of the stock solutions for long-term storage, 4) stability of the resulting dye, and 5) high water solubility. There have been no conventional reagents so far that meet all of these criteria. In the effort to develop such a compound, we recently synthesized the following new reagents for colorimetric enzymatic determination. A series of oxidative chromogenic reagents, Bis-MAPS, do not require any coupling reagents in the peroxidase-mediated oxidation reaction producing dyes that absorb at 650 nm with a large molar absorptivity. New coupling reagents, NCP, give a green color upon reaction with the aniline derivatives known as Trinder's reagents. Hydrogen donors, DADB, were found not to suffer from interference by bilirubin. As a reductive chromogen for use in clinical diagnosis like LDH analysis, we have developed a novel tetrazolium salt, WST-1, that produces a highly water soluble formazan dye. WST-1 proved to be also valuable as a chromogenic indicator in cell proliferation assays where MTT is used most widely.View full abstractDownload PDF (1877K) -
Shinjiro HAYAKAWA1996 Volume 45 Issue 2 Pages 125-134
Published: February 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA scanning X-ray microprobe using synchrotron radiation was developed employing an X-ray focusing system with total reflection mirrors. Utilizing a Wolter mirror system, a hard X-ray microbeam was first realized. With an energy tunable X-ray microprobe, sensitivity in X-ray fluorescence (XRF) analysis can be optimized for the element of interest at less than 1 ppm in relative concentration. Moreover, small area X-ray absorption fine structure (XAFS) measurements with XRF detection can provide chemical state information about a trace element in a sample. To fully utilize the X-ray microprobe, an XRF quantification method for intermediate thick samples was proposed and the effects of self-absorption in the XRF yield XAFS measurements were discussed.View full abstractDownload PDF (1327K) -
Hajime OHTANI1996 Volume 45 Issue 2 Pages 135-156
Published: February 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSIn this work, high-performance pyrolysis-GC/MS was successfully applied to 1) the minor- and microstructural characterization of various polymeric materials in practical use such as end groups in poly(methyl methacrylate)s and polystyrenes, copolymer sequences in polysiloxanes, stereoregularities in polystyrenes, and determination of diene moieties in vulcanized ethylene-propylene-diene rubbers, 2) characterization of fully aromatic polyesters and stabilized polyacetals by reactive pyrolysis in the presence of organic alkali and solid acid, respectively, 3) development of a new stepwise pyrolyzer and its application to formulated rubbers and macromonomers, 4) highly sensitive determinations of trace additives in paper, and 5) detailed analysis of thermal degradation of polystyrene and fully aromatic polyester using partly deuterated polymer samples.View full abstractDownload PDF (2427K) -
Yukie HAYASHI, Kiyoshi TAKEDA, Masakazu KITA, Kensuke CHIKAMORI, Yasuh ...1996 Volume 45 Issue 2 Pages 157-162
Published: February 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSWe attempted to distinguish the "free" cupric ion from the total copper in river waters originating from an old copper mine because the toxicity is generally attributed to the aquocomplexed free cupric ion. The total concentration of copper in the sample solutions was determined by atomic absorption spectrometry; the free cupric ion was analyzed with a copper ion-selective electrode. About 200 samples of river water around the copper mine were analyzed from November of 1993 to December of 1994. The concentration of free cupric ion at most stations is less than 1 ppm except for that near the H-8 point, where leaching water from the mine slag was led to a rock reservoir (30 cm in diameter and 1 m high) and the stored water overflowed from the reservoir. The leaching water stored in the reservoir had the highest concentration of the free cupric ion, averaging of 9.5 ppm. Fishes inhabit only the upper valley of the river and do not move into the lower valley. Fishes can not move to the downstream because of contaminating copper around the inner valley.View full abstractDownload PDF (722K) -
Sanae IKEDA, Ryousaku ARIMITSU, Junko MOTONAKA1996 Volume 45 Issue 2 Pages 163-167
Published: February 05, 1996
Released on J-STAGE: May 25, 2010
JOURNAL FREE ACCESSA novel ion chromatography for the determination of amino acids was developed. The eluted amino acids were monitored by conductometric-UV detection using copper(II) acetate reagent. Amino acids were separated on a reverse-phase column, ODS-80Ts (5 μm, 150 mm × 4.6 mm i.d.) with water as the eluent. It was not necessary to adjust the pH of the post-column solution when copper(II) acetate was used. Five amino acids (valine, methionine, leucine, tyrosine, phenylalanine) in soy sauce were simultaneously determined.View full abstractDownload PDF (461K) -
Hiroyuki YAMAMOTO, Yuji BABA, Teikichi A.SASAKI1996 Volume 45 Issue 2 Pages 169-174
Published: February 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe analyzing depth of X-ray photoelectron spectroscopy (XPS) depends on the inelastic mean free path (IMFP) of a photoelectron. Since the IMFP of a photoelectron is a function of its kinetic energy, the analyzing depth of XPS changes with the excitation energy. We apply this relationship to the depth profile analysis of XPS measurements by using energy tunable synchrotron radiation (SR) X-rays. For this purpose, a "High-energy SR-XPS" has been constructed and applied to the depth profile analysis of the two kinds of oxide layer on Si(100) surfaces. These are, 1)the thermally oxidized surface, which is well defined as a thin uniform film of SiO2, and 2)the O2+ -ion implanted surface, which has a depth distribution of oxide. The thickness of the oxide layer and the depth profile of the O2+ -ion implanted layer have been estimated by measuring the intensities of elemental Si to the intensity of SiO2, which are observed from the Si ls XPS spectra at the various photon energies. The results obtained suggest that the present system is feasible for the depth profile analysis of thin films.View full abstractDownload PDF (705K) -
Kimitoshi SATO, Motoyuki SUZUKI, Kusdiana HILMAN, Takashi GOTO1996 Volume 45 Issue 2 Pages 175-179
Published: February 05, 1996
Released on J-STAGE: May 07, 2010
JOURNAL FREE ACCESSSeparation and preconcentration of trace molybdenum(VI) from aqueous solution for graphite furnace atomic absorption spectrometric determination (GF-AAS) was studied using silica gel loaded with trioctylmethylammonium chloride (Capriquat). A sample solution of 100500 ml containing Mo(VI) was mixed with 100 mg of Capriquat loaded silica gel under stirring for 10 min using an ultrasonic bath. The solution was then passed through a membrane filter (pore size 0.45μm). The Mo(VI) collected on the Capriquat loaded silica gel together with the membrane filter is eluted with 10 ml of 0.03 M perchloric acid and then determined by GF-AAS. In this method, over 99% of the Mo(VI) was adsorbed at about pH 4.0. The calibration curve was linear from 0.05 to 3.0 μg of Mo(VI). The proposed method has been applied to the determination of Mo(VI) in tap water and river water.View full abstractDownload PDF (483K) -
Michio ZENKI, Hidenori YUKUTAKE, Masaru IRIZAWA1996 Volume 45 Issue 2 Pages 181-184
Published: February 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe separation behavior of naphthalenesulfonates (NSs) by capillary zone electrophoresis (CZE) has been investigated. Since the structural isomers of naphthalenemonosulfonate (NMS) and naphthalenedisulfonate (NDS) were identical at normal pH, modifiers such as surfactants and water soluble polymers were added to the electrophoretic buffer solution (20 mM borax, pH 9.2). Among those tested, polyethylene glycol (PEG, n=2000) was found to be the best modifier for the separation of NSs with high resolution. Structural isomers of two NMSs and four NDSs were successfully separated within 17 min by using a 37.8 cm × 75-μm i.d. fused silica capillary. The separation of NSs was also investigated by two methods of reversed-phase HPLC using a C18 column. The elution orders of NDS isomers obtained by both CE and HPLC differed from each other, which indicates that many factors affect on the separation of NSs.View full abstractDownload PDF (379K) -
Hongton LI, Takeshi NAGANUMA1996 Volume 45 Issue 2 Pages 185-187
Published: February 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSCationic dyes formed ion-association complexes with tribromo mercury(II) in aqueous solution. The complexes formed were adsorbed on a polyvinyl chloride sheet (soft type), and the colored species adsorbed were used for the measurement of mercury. The optimum concentrations of KBr, H2SO4 and Rhodamine B were 1×10-2 M (M=mol dm-3), 0.3 M and 1×10-4 M, respectively. The detection limit of Hg was 0.04 ppm at shaking time of 10 min. and 35°C. The proposed method is similar to ion pair solvent extraction but is simple and is more desirable than solvent extraction because it does not need any organic solvents.View full abstractDownload PDF (258K) -
Hidenobu NAKAO, Tsutomu NAGAOKA, Kotaro OGURA1996 Volume 45 Issue 2 Pages 189-192
Published: February 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSWe studied the ion exchange properties of a conducting-polymer composite colloid consisting of polyaniline(PA) and polyvinyl alcohol(PVA). The colloid was soluble in aqueous solution as well as organic solvents such as dimethyl sulfoxide. The solution was stable for more than one week. It was shown that dispersions of PAPVA colloid are active electrochemically and exchange anions in the solution with anions in the PAPVA colloid. Furthermore, the PAPVA colloid can exchange organic anions, showing effective extractability for anions.View full abstractDownload PDF (350K) -
Michihiro AIMOTO, Mitsunori KOMODA, Koichi CHIBA1996 Volume 45 Issue 2 Pages 193-199
Published: February 05, 1996
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSWe designed a new, simple and precise continuous-flow type analytical method for nitrogen determination combining flow injection analysis (FIA) and waveguide capillary cell (WCC) spectrophotometry. We used a gas-diffusion FIA system for sample preparation and introduction. We prepared steel solution decomposing steel sample with hydrochloric acid. First, nitrogen forms NH4+ in solution changes into NH3 gas in strong alkaline media. Only NH3 gas is separated from the matrix through porous Teflon membrane tubing. Finally, an indophenol type blue dye is produced by the reaction of NH3 gas and some color-producing reagents for spectrophotometric detection. As the detector, we applied the WCC spectrophotometer. A 50 cm long WCC enhances the sensitivity about 50-times compared with a 1 cm conventional cell. By this method, the analytical results of nitrogen determination in four certified reference materials conformed well with the certified values. The variation for 2 μgN per g steel was about 3% (n=3). Moreover, comparing the analytical results of the proposed method with those of the conventional (JIS) method by using two steel sample, we found good agreement.View full abstractDownload PDF (788K) -
Nobuaki MATSUOKA, Hidehisa KAWAMURA, Kunio SAEKI, Masami KOIKE, Noriyu ...1996 Volume 45 Issue 2 Pages 201-206
Published: February 05, 1996
Released on J-STAGE: May 25, 2010
JOURNAL FREE ACCESSThe 207Pb/206 Pb and 208Pb/206Pb ratios in ancient bronze mirrors were measured using ICP-MS. The sample solution for ICP-MS was prepared by dissolving the mirror rust in a mixture of hydrochloric and nitric acid. ICP-MS analyses of the sample solution were repeated 10 times under adequate conditions, in the range of the relative standard deviation of 0.20.4% for 207Pb/206Pb and 208Pb/206 Pb ratios. In addition, the simultaneous analysis of standard solution enabled us to normalize the isotope ratios in a bronze mirror to the NIST standard. From the analytical results, the raw materials of two ancient mirrors, which had been excavated from the northern part of Kyushu island, were considered to have originated either in China after the Eastern Han dynasty, or the Korean peninsula.View full abstractDownload PDF (722K) -
Takahisa TSUGOSHI1996 Volume 45 Issue 2 Pages 207-208
Published: February 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSIt has been difficult to obtain chemical-state information in microprobe analysis. This thesis presents the application and development of laser microprobe mass spectrometry (LAMMS) for this purpose. In the first study, analysis of an insulating polycarbonate surface treated with a silane coupling agent is presented. The surfactant in the agent is effective for generating different chemical species in the treated layers and for their homogenization. The second study describes the sensitive detection of acid components on deteriorated stone. The detection of nitrogen- and sulfur-oxide ions indicates the acceleration of stone deterioration by acid rain. In the third study, a structural interpretation of the silicate network is carried out using the Si/O ratio of the fragment ions. The calculated Si/O ratio coincided with the ratio obtained from the fragment ions detected, depending on the network structure. In the fourth study, the time dependence of ionization is presented. Since a high power laser pulse makes the fine structure of secondary ionization observable, the behavior difference between Al and Au has become clear. In conclusion, LAMMS is useful for sensitive chemical-state and microprobe analysis, especially of insulator materials. Further it is suggested that the interpretation of ionization behavior due to the thermal process has possibility for a new chemical-state analysis.View full abstractDownload PDF (287K)
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