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Chunxia ZHAO, Guowang XU, Xianzhe SHI, Jianmei MA, Yan ZHANG, Shen LV, ...
2004 Volume 20 Issue 7 Pages
1001-1005
Published: 2004
Released on J-STAGE: December 07, 2004
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Fluorescent-based single-strand conformation polymorphism (F-SSCP) analysis with capillary electrophoresis (CE) is the most common method for the detection of mutation because of its high sensitivity and resolution. In this study, we prepared an inexpensive linear polyacrylamide (LPA), and successfully applied it to CE-SSCP analysis and tandem CE-SSCP/heteroduplex analysis (HA) of the P53 gene on an ABI capillary genetic analyzer. A comparison of the sieving capabilities of a homemade LPA and commercial polydimethylacrylamide (PDMA) demonstrates that the homemade LPA has a higher resolution, a shorter analysis time, and is more suitable for tandem SSCP/HA than commercial PDMA. To show the usefulness, mutations of P53 gene exon 7 - 8 in 37 tumor samples were investigated by using homemade LPA. The results indicate that 10 mutations were found in 9 of 37 cases; the majority of P53 mutations were missense mutations, and 70% were located in exon 7, which plays an important role in neoplastic progression in human tumorigenesis.
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Mohammad REZA GANJALI, Morteza REZAPOUR, Mohammad REZA POURJAVID, Sohe ...
2004 Volume 20 Issue 7 Pages
1007-1011
Published: 2004
Released on J-STAGE: December 07, 2004
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N-[2-[4-[[[(Cyclohexylamino)carbonyl]amino]sulfonyl]phenyl]ethyl]-5-methyl pyrazine carboxamide (glipizid) was explored as an electro-active material for preparing a polymeric membrane-based sensor selective to samarium ions. The membrane incorporated 30% poly(vinyl chloride) (PVC), 53% benzyl acetate (BA), 11% glipizid and 6% sodium tetraphenyl borate. When coated on the surface of a graphite electrode, it exhibits Nernstian responses in the concentration range of 1.0 × 10
-5 to 1.0 × 10
-10 M, with a detection limit of 8.0 × 10
-11 M samarium. The electrode shows high selectivity towards samarium over several cations (alkali, alkaline earth, transition and heavy metal ions), and specially lanthanide ions. The proposed sensor has a very short response time (< 15 s), and can be used in a wide pH range for at least ten weeks. It was used as an indicator electrode in potentiometric titration of Sm(III) ions with an EDTA solution, and for determination of samarium in binary and ternary mixtures.
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Leyu WANG, Lun WANG, Tingting XIA, Ling DONG, Guirong BIAN, Hongqi CHE ...
2004 Volume 20 Issue 7 Pages
1013-1017
Published: 2004
Released on J-STAGE: December 07, 2004
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Under ultrasonic irradiation, organic fluorescence nanoparticles have been prepared by a reprecipitation method. Compared with single organic fluorophores, these nanoparticles are brighter, more stable against photobleaching and more water-soluble. They also have high room-temperature fluorescence quantum yields (∼20%) and a long fluorescence lifetime (∼0.2 µs). Based on the fluorescence quenching of nanoparticles by chromium(VI), a method for the selective determination of chromium(VI) without the separation of chromium(III) in water was developed. Under the optimal conditions, the linear range of the calibration curve was 7.0 × 10
-6 - 1.0 × 10
-4 mol L
-1. The detection limit was 2.8 × 10
-6 mol L
-1. The method is characterized by a short reaction time, stable fluorescence signals, simplicity and high selectivity. The present assay has been applied to the selective quantification of Cr(VI) in wastewater with satisfactory results.
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Xinyu CHEN, Yoshiro ORO, Kenta TANAKA, Norimichi TAKENAKA, Hiroshi BAN ...
2004 Volume 20 Issue 7 Pages
1019-1023
Published: 2004
Released on J-STAGE: December 07, 2004
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A new stripping coil for the collection of nitrogen dioxide (NO
2) has been developed to increase its versatility and efficiency. Nitrogen dioxide measurements based on quantitative collection through a reaction coil into an alkaline solution has been examined. Nitrogen dioxide is collected in a 0.1 N NaOH solution. This collection system has an efficiency of nearly 100%. The absorbed nitrogen dioxide has been measured by fluorescence detection with sub-ppbv detection limits. The excitation wavelength at 360 nm and the produced emission wavelength at 405 nm were suitable for nitrite ion measurements.
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Yuichi TAKAKU, Takuma HAYASHI, Ikuko OTA, Hidenao HASEGAWA, Shinji UED ...
2004 Volume 20 Issue 7 Pages
1025-1028
Published: 2004
Released on J-STAGE: December 07, 2004
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An analytical method for trace levels of iron in a seawater sample using isotope dilution ICP-MS was developed. Preconcentration of iron and the removal of major elements in seawater such as alkali and alkaline-earth elements can be carried out quickly using a chelating resin disk by adjusting the sample pH to 3. The collision cell option of the ICP-MS instrument method was used to improve the performance of the instrument for iron measurements since ArO and ArN interferences could be reduced using this analytical method. About 4 ml min
-1 helium, as the collision gas, were introduced into the cell.
40Ar
14N and
40Ar
16O which interfere with
54Fe and
56Fe in water had their amounts decreased by 5 orders of magnitude. Then, the isotope dilution method was used for iron determination below ng g
-1 level of trace iron in four environmental reference materials (river water standard sample JAC-0031 (Japan Soc. for Analytical Chemistry), estuarine standard sample SLEW-2 (NRC Canada) and seawater standard samples CASS-3 and NASS-5 (NRC Canada)) were measured. Good agreement between analytical results and certified values of reference materials was obtained, which confirmed the effectiveness of this method.
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Ilton L. ALCÂNTARA, Paulo S. ROLDAN, Gustavo R. CASTRO, Fabr&iac ...
2004 Volume 20 Issue 7 Pages
1029-1032
Published: 2004
Released on J-STAGE: December 07, 2004
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A rapid and sensitive method was developed to determine trace levels of Cd
2+ ions in an aqueous medium by flame atomic absorption spectrometry, using on-line preconcentration in a mini-column packed with 100 mg of 2-aminothiazol modified silica gel (SiAT). The Cd
2+ ions were sorbed at pH 5.0. The preconcentrated Cd
2+ ions were directly eluted from the column to the spectrometer’s nebulizer-burner system using 100 µL of 2 mol L
-1 hydrochloric acid. A retention efficiency of over 95% was achieved. The enrichment factor (calculated as the ratio of slopes of the calibration graphs) obtained with preconcentrations in a mini-column packed with SiAT (
A = -1.3 × 10
-3 + 1.8 × 10
-3[Cd
2+]) and without preconcentrations (
A = 4 × 10
-5 + 3.5 × 10
-5[Cd
2+]), was 51 and the detection limit calculated was 0.38 µg L
-1. The preconcentration procedure was applied to determine trace levels of Cd in river water samples. The optimum preconcentration conditions are discussed herein.
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Isoshi NUKATSUKA, Yutaka SHIMIZU, Kunio OHZEKI
2004 Volume 20 Issue 7 Pages
1033-1036
Published: 2004
Released on J-STAGE: December 07, 2004
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Cellulose derivative resin (CDR) suspensions containing resin particles of cellulose nitrate (CDR(CN)), cellulose acetate (CDR(CA)), or cellulose triacetate (CDR(CTA)) were prepared as the sorbent for resin suspension injection (RSI) electrothermal atomic absorption spectrometry (ETAAS), in which fine resin particles holding a desired trace element were directly injected into the graphite tube as the suspension. To compare the sorption ability, the distribution ratios of the Mo(VI)-phenylfluorone complex were measured between the aqueous phase and the sorbents, including the CDRs mentioned above and the finely divided anion exchange resin (AR). The results showed that the sorption ability decreases in the following order: CDR(CN) ≥ AR > CDR(CA) ≥ CDR(CTA). It was concluded that CDR(CN) was able to extract more than 98% of Mo(VI), and was suitable for RSI-ETAAS as well as AR. CDR(CN) was used for the determination of Mo in NIES certified reference materials, No. 10 Rice flour-unpolished; the results showed fairly good agreements between the analytical values and the certified values.
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Jianjun XIA, Wanzhi WEI, Yanbo HU, Han TAO, Ling WU
2004 Volume 20 Issue 7 Pages
1037-1041
Published: 2004
Released on J-STAGE: December 07, 2004
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A novel voltammetry with a modified gold electrode for the direct determination of copper in environmental samples, without any pretreatment, is proposed in this paper. A porous disorganized monolayer was formed on the surface of the gold electrode by the self-assembly of mercaptoacetic acid (MAA), which could selectively permeate small molecules. Subtractive square wave anodic stripping voltammetry (SASV) was applied to determine copper, in which the underpotential deposition (UPD) of copper was used as the deposition step. The linear range was from 8 × 10
-7 to 1 × 10
-5 mol l
-1 by the modified electrode in the presence of human serum albumin, and the determination was not interfered with common metal ions. Copper in a real environmental sample was successfully detected.
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S. I. M. ZAYED
2004 Volume 20 Issue 7 Pages
1043-1048
Published: 2004
Released on J-STAGE: December 07, 2004
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Triprolidine (Trip) ion selective electrodes of three types: the conventional polymer membrane (I), graphite coated electrode (II) and carbon paste electrode (III), have been prepared, based on the ion pair of triprolidine hydrochloride with sodium tetraphenylborate. The electrodes exhibit a linear response with a mean calibration graph slope of 56.12, 55.00 and 54.32 mV decade
-1 at 25°C for I, II and III, respectively, within the concentration ranges 1.96 × 10
-5 - 1.00 × 10
-2 M for I and 3.84 × 10
-5 - 1.00 × 10
-2 M for II and III. The detection limits are 1.13 ± 0.13 × 10
-5, 1.70 ± 0.06 × 10
-5 and 1.78 ± 0.05 × 10
-5 M for the three electrodes, respectively. The change of pH within the ranges 4.85 - 8.75 and 4.70 - 8.50 for I and III, respectively, did not affect the electrode performance. The standard electrode potentials were determined at different temperatures and were used to calculate the isothermal coefficient of the electrode. The electrodes showed a very good selectivity for Trip with respect to a large number of inorganic cations and compounds. The standard addition method was applied to the determination of TripCl in pure solution, pharmaceutical preparations, and urine samples.
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Chengguo HU, Qiong HE, Qing LI, Shengshui HU
2004 Volume 20 Issue 7 Pages
1049-1054
Published: 2004
Released on J-STAGE: December 07, 2004
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The electrochemical response of thyroxine (T
4) at a carbon paste electrode (CPE) in the presence of cetyltrimethylammonium bromide (CTAB) was investigated. It gave a well-defined oxidation peak at 0.80 V and a sensitive reduction peak at 0.40 V. Compared with the indiscernible signal in the absence of CTAB, the reduction current of T
4 at CPE was greatly enhanced in the presence of CTAB, due to the interactions between T
4, CTAB and the hydrophobic electrode surface. The electrode process of T
4 was explored by cyclic voltammetry and chronocoulometry. The effect of surfactants on the reduction reaction proved that bromide ions (Br
-) in CTAB might form special ion complexes with T
4 via a special interaction with the iodine atoms on T
4, which would activate the reduction of T
4. The sensitive and selective reduction of T
4 in this system was applied to the determination of T
4 in drugs; a detection limit of 6.5 × 10
-9 M was obtained (σ = 3).
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Lingyan JIANG, Chuanyin LIU, Liping JIANG, Zhen PENG, Guanghan LU
2004 Volume 20 Issue 7 Pages
1055-1059
Published: 2004
Released on J-STAGE: December 07, 2004
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A chemically modified electrode based on a chitosan-multiwall carbon nanotube (MWNT) coated glassy carbon electrode (GCE) is described, which exhibits an attractive ability to determine dopamine (DA) and ascorbic acid (AA) simultaneously. The modified electrode exhibited a high differential pulse voltammetry (DPV) current response to DA at 0.144 V and AA at -0.029 V (
vs. SCE) in a 0.1 mol l
-1 phosphate buffer solution (pH = 7.2). The properties and behaviors of the chitosan-multiwall carbon nanotube modified electrode (MC/GCE) were characterized using cyclic voltammetry (CV) and DPV methods. The mechanism for the discrimination of dopamine from ascorbic acid at MC/GCE is discussed. The linear calibration range for DA and AA were 5 × 10
-7 mol l
-1 to 1 × 10
-4 mol l
-1 (
r = 0.997), and 5 × 10
-6 mol l
-1 to 1 × 10
-3 mol l
-1 (
r = 0.996), respectively. The MC/GCE showed good sensitivity, selectivity and stability.
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Takao TSUDA, Mahoro HISANAGA, Takanori INAGAKI, Shinya KITAGAWA, Kanji ...
2004 Volume 20 Issue 7 Pages
1061-1064
Published: 2004
Released on J-STAGE: December 07, 2004
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A new type of fiber adsorbent attached with silica microparticles was prepared. The silica microparticles were formed by the polymerization of silica oligomers on glass fibers, which were woven into a glass filter. The surface of the silica microparticles was chemically modified by bonding C
18-ligands. SEM images indicated that the diameter of the uniform and spherical silica microparticles fixed on glass fibers was on the order of micrometers. It was confirmed that the glass filter adsorbent was effective for the adsorptive removal of toluene of low concentrations.
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Hitoshi KODAMATANI, Keiitsu SAITO, Nobumitsu NIINA, Shigeo YAMAZAKI, A ...
2004 Volume 20 Issue 7 Pages
1065-1068
Published: 2004
Released on J-STAGE: December 07, 2004
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A new sensitive determination method of domoic acid based on the chemiluminescent reaction of tris(2,2′-bipyridine)ruthenium(III) has been developed. The method exhibited good reproducibility. The relative standard deviation of six replicate measurements was 1.6% for 10 ng ml
-1. A calibration graph, based on a standard domoic acid solution, was linear over the range of 1 - 500 ng ml
-1 (coefficient of correlation,
r2 = 0.9995) and the detection limit was 8 pg (signal-to-noise ratio = 3) without any preconcentration and derivatization steps. This new method was successfully applied to a real sample of blue mussels spiked with 2 µg g
-1 domoic acid.
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Eiji KANEZAKI, Suminori TANAKA, Kei-ichiro MURAI, Toshihiro MORIGA, Ju ...
2004 Volume 20 Issue 7 Pages
1069-1073
Published: 2004
Released on J-STAGE: December 07, 2004
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Phase changes between PdO and Pd metal can be directly detected in PdO/CeO
2 catalysts supported on χ-Al
2O
3 by means of
in situ high-temperature measurements of X-ray diffraction and FT-IR in relation to the catalytic activity for the methane oxidation of microcrystalline PdO. Reversible changes in the solid phases are observed from PdO to Pd and Pd to PdO under O
2-deficient and O
2-excess atmospheres, respectively. Nanosizes of PdO and Pd crystallites, the distorted PdO crystal structure along the (110) plane, and also a distorted Pd metal crystal structure along the (200) plane as well as the large surface area elucidate the high catalytic activity for the methane oxidation of PdO/CeO
2 catalysts prepared with an atomic ratio of Pd:Ce = 1:1.
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Shilv CHEN, Hongwu MA, Huichun ZHAO, Ruiqing FENG, Linpei JIN
2004 Volume 20 Issue 7 Pages
1075-1078
Published: 2004
Released on J-STAGE: December 07, 2004
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A simple, rapid and highly sensitive fluorometric method for the determination of pazufloxacin mesilate (PZFX) is described. It is based on the formation of the complex [Tb(PZFX)
2]
3+, which shows the intensive characteristic bands of Tb
3+. Optimum conditions for the determination were investigated. Under the optimum experimental condition, the fluorescence intensity responds linearly to the PZFX concentration in the range of 2.0 × 10
-8 - 5.0 × 10
-6 mol/l with a detection limit of 6.2 × 10
-9 mol/l. The method has been successfully applied to the determination of PZFX in urine and serum samples.
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Yuko NISHIMOTO, Yoichi KANEKI, Akira KISHI
2004 Volume 20 Issue 7 Pages
1079-1082
Published: 2004
Released on J-STAGE: December 07, 2004
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A simultaneous low-temperature X-ray powder-diffractometric (XRD)-DSC technique was applied to the solid state and melting process of frozen aqueous solutions of 2-propanol.
1H NMR spectra were also obtained at low temperatures. The chemical shifts of the CH
3 proton and the CH proton can be classified into four temperature regions: higher than -20°C, around -20°C, -50 to -20°C, and lower than -50°C. In the XRD data, five small diffraction peaks for 2 θ at 21.0°, 25.2°, 27.8°, 31.1° and 32.1° can be attributed to the peritectic, while five diffraction peaks at 22.5°, 24°, 25.6°, 33.4° and 39.8° can be attributed to ice; these peaks are due to the hexagonal form of ice, which disappears upon melting. However, the diffraction peak at 33.4° showed a different pattern than the other peaks due to hexagonal ice. These results indicate that the temperature dependence of the diffraction peak at 33.4° for 2
θ is related to the formation of hydrogen bonds between 2-propanol and water. The simultaneous XRD-DSC technique was effective for investigating this water-alcohol mixture at low temperatures.
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Aiguo WU, Zhuang LI, Erkang WANG
2004 Volume 20 Issue 7 Pages
1083-1086
Published: 2004
Released on J-STAGE: December 07, 2004
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We have fabricated DNA network structures on glass and sapphire substrates. As a comparison, we also formed the network structure on mica substrate. For titanate strontium substrate, however, DNA network can not be obtained even if it is wet-treated by Na
2HPO
4 solution to make it hydrophilic. We also discuss the factors that affect the DNA networks formed on various substrates.
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Meng HENG, Katsuo MURATA
2004 Volume 20 Issue 7 Pages
1087-1090
Published: 2004
Released on J-STAGE: December 07, 2004
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A new method was devised for measuring the pH of a concrete surface by pHBOY-P2 with a piece of filter paper by extracting the pH value from concrete. This is a simple and inexpensive method that does not damage the concrete building, and is easy to apply on concrete samples for monitoring. By using the method mentioned above, a drastic decrease of the pH value of concrete bridges and buildings has investigated. The method is environmentally friendly to detect the pH value change of concrete as an environmental sample investigation.
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Akira OHASHI, Akira TSUGUCHI, Hisanori IMURA, Kousaburo OHASHI
2004 Volume 20 Issue 7 Pages
1091-1093
Published: 2004
Released on J-STAGE: December 07, 2004
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The cloud point extraction behavior of aluminum(III) with 8-quinolinol (HQ) or 2-methyl-8-quinolinol (HMQ) and Triton X-100 was investigated in the absence and presence of 3,5-dichlorophenol (Hdcp). Aluminum(III) was almost extracted with HQ and 4(v/v)% Triton X-100 above pH 5.0, but was not extracted with HMQ-Triton X-100. However, in the presence of Hdcp, it was almost quantitatively extracted with HMQ-Triton X-100. The synergistic effect of Hdcp on the extraction of aluminum(III) with HMQ and Triton X-100 may be caused by the formation of a mixed-ligand complex, Al(dcp)(MQ)
2.
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Habibollah ESKANDARI, Yousef KAMALI
2004 Volume 20 Issue 7 Pages
1095-1098
Published: 2004
Released on J-STAGE: December 07, 2004
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The H-point standard addition method (HPSAM) has been applied for the simultaneous determination of nickel and copper in trace levels, using 1-(2-pyridylazo)-2-naphthol (PAN) as a chromogenic reagent in aqueous Tween 80 micellar media. Under the optimum condition, the simultaneous determinations of nickel and copper by HPSAM were performed. The absorbances at one pair of wavelengths, 548 and 579 nm, were monitored with the addition of standard solutions of copper. The method is able to accurately determine copper-to-nickel ratios of 15:1 to 1:10 (Wt/Wt). The effects of diverse ions on the determination of nickel and copper to investigate the selectivity of the method were also studied. The recommended procedure was successfully applied to some water and alloy samples.
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Nobutaka ENDO, Rei IKUTA, Mitsuru HIGA, Koji MATSUSAKI
2004 Volume 20 Issue 7 Pages
1099-1101
Published: 2004
Released on J-STAGE: December 07, 2004
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In order to change the ion-exchange selectivity of anion-exchange resin, the surface of a gel-type anion exchange resin was modified with anionic polyelectrolyte, polystyrenesulfonic acid. Using this modified resin, the ion-exchange rate of nitrate was little decreased, but that of sulfate was evidently decreased. It is considered that the ion-exchange reaction of the multivalent anion is suppressed by the greater electrostatic repulsive force against the modification layer than that against the monovalent anion. Thus, this modified resin may be suitable for the selective separation of monovalent anions. The influence of the modified condition on the ion-exchange rate was examined. Furthermore, this modified resin was used to separate nitrate ions from sulfate ions in the aqueous solution.
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Wei WU, Zhiqiang LIU, Fengrui SONG, Shuying LIU
2004 Volume 20 Issue 7 Pages
1103-1105
Published: 2004
Released on J-STAGE: December 07, 2004
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Seven structure analogical flavonoid aglycones have been analyzed using electrospray ionization tandem mass spectrometry (ESI-MS
n) in the negative-ion mode. The spectra obtained ESI-MS
n allowed us to propose plausible schemes for their fragmentation mechanism. By analyzing the product ions spectra of deprotonated molecule ions [M-H]
-, some neutral diagnostic losses and specific retro Diels-Alder fragments were obtained. By using all of these characteristic fragment ions we can specially differentiate the flavone isomer.
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