Vol. 4 8, No. 1 1
November, 1999
Kiyokatsu Jinno and Hirokazu Sawada*
*School of Materials Science, Toyohashi University of Technology, Toyohashi-shi, Aichi 441-8580
(Received 18 June 1999)Capillary electrochromatography (CEC), which combines the advantages of high efficiency of capillary electrophoresis (CE) and high selectivity of liquid chromatography (LC), has recently received considerable attention. Most CEC experiments have been performed with capillary columns packed with small LC packing materials (1.5 µm particle diameter). However, some problems, such as difficulties in packing the small LC packing materials and fabricating the frit, still exist in preparing the CEC column. The use of open-tubular columns in CEC is an alternative approach that eliminated such problems. So far, several types of open tubular columns have been reported for CEC separation.
In this review, recent progress in open-tubular columns for CEC is described.
Keywords : capillary electrochromatography; open-tubular columns; stationary phase; microchip.
Hideo Asakura, Katsushige Ikegami* and Hisanobu Wakita**
*Research Center, Shinagawa Refractories Co., Ltd., 707, Imbe, Bizen-shi, Okayama 705-8577
**Department of Chemistry, Faculty of Science, Fukuoka University, 8-19-1, Nanakuma, Jonan-ku, Fukuoka 814-0133
A glass-bead technique has been prepared under low temperature using a low flux-to-sample ratio molten mixture for the determination of the fluorine in calciumsilicate-fluoride composite materials by X-ray fluorescence spectrometry, because fluorides lose unnegligible amounts of fluorine at high temperature and the analytical line FKα for fluorine has low sensitivity. In the case of a 1:1 flux(LiBO2)-to-sample, the test piece of this mixture began to contract at 640°C, became globular at 710°C and became transparent glass at over or around 760°C. A glass bead of a 1:1 flux-to-sample was successfully obtained by melting at 780°C for 10 minutes. Under these conditions, the reproducibility of the preparation of glass beads for samples containing artificial cryolite, which lost fluorine at high temperature, was found to be 0.154% as the relative standard deviation. In spite of the kinds of fluoride which were in the fluorine source, the samples could be homogenized by the glass-bead technique. The fluorine calibration equation can be regard as a CaO-CaF2 binary calibration according to the JIS correction model, making it possible to calculate the theoretical matrix correction coefficients(dj). The calibration also necessitated an overlapping correction for FeLα and MnLα. The fluorine calibration equation showed good precision, with 0.017 mass% as the standard deviation; it was possible to determine the fluorine from 0.2 to 12 mass% in many kinds of calciumsilicate-fluoride composite materials.
Keywords : fluorine; X-ray fluorescence spectrometry; low dilution glass bead prepared under low temperature; calciumsilicate-fluoride composite.
Motoyasu Sugiura, Masao Tsuji, Atsushi Murase and Takuya Mitsuoka**
**Toyota Central R&D Labs. Inc., 41-1, Nagakute, Nagakute-cho, Aichi 480-1192
(Received 9 June 1999, Accepted 11 August 1999)An analytic method, referred to as "derivatization/electron probe X-ray micro-analysis (EPMA)" has been developed to determine the distribution of a small amount of carbonyl groups formed by the oxidation of polymers by chemical derivatization with 2,4,6-trichlorophenylhydrazine(TCPH). A suitable condition of the derivatization reaction with carbonyl groups in polymers was investigated. It was found that the highest reaction yield and selectivity were obtained by heating the sample in a 2.5% TCPH/acetic acid solution at 90°C for 30 min. Acetic acid was used as a catalyst and a solvent. By derivatization/EPMA using this reaction condition, a distribution measurement of the carbonyl group in the polymer became possible in 0.01% of the detection limits. Actual applications to a depth analysis of degraded ethylene-carbon mono oxide copolymer and polyethylene proved that this method is useful for the characterization of polymers and studies on polymer degradation.
Keywords : distribution analysis; chemical derivatization; electron probe X-ray microanalysis; polyolefin; carbonyl group.
Koichi Yamamoto and Noritsugu Matsuura*
*Department of Materials Science, Yonago National College of Technology, 4448, Hikona-cho, Yonago-shi, Tottori 683-8502
(Received 5 July 1999, Accepted 25 August 1999)A method for the spectrophotometric determination of surfactants (cationic surfactants (CS+), such as quaternary ammonium salts, anionic surfactants (AS-), such as sodium lauryl sulfate and sodium alkyl sulfonate, and polyoxyethylene non-ionic surfactants (NS), containing a long-chain alkyl group) with Erythrosine B (EB), has been developed. The addition of CS+ to an EB solution buffered at pH 5.7 led to an increase in the absorbance at 549 nm; also, when AS- was added to the solution, the absorbance at 549 nm decreased with increasing the amount of AS-. This decrease in the absorbance was caused by an ion association of CS+ with AS-. A calibration graph based on this principle shows linearity up to 5×10-6 M of CS+ and AS- and from 10-6 to 10-4 M order of NS. The proposed method is simple and rapid, and there is no use of toxic organic solvents. It was applied to the determination of anionic surfactants in commercial detergents for washing and kitchen, and cationic surfactants in commercial rinsing solutions for hair, the results of which were in good agreement with those of the JIS titration method (Epton method); also, it was applied to both the identification and the determination of non-ionic surfactants in commercial detergents for washing.
Keywords : spectrophotometry; determination of ionic and non-ionic surfactants; Erythrosine B; ion association of quaternary ammonium ion with anionic surfactants.
Koji Matsusaki, Masanori Nagahiro and Toshikatsu Sata*
*Department of Applied Chemistry and Chemical Engineering, Faculty of Engineering, Yamaguchi University, Tokiwadai, Ube-shi, Yamaguchi 755-8611
(Received 7 April 1999, Accepted 6 September 1999)The surface of a gel-type anion exchange resin in the hydroxide form was modified by the adsorption of an anionic polyelectrolyte: a polycondensation product of sodium naphthalene sulfate and formaldehyde. After adsorption of the polymer, the rate of the ion-exchange reaction became slow. Especially, the ion-exchange rate of the sulfate ion was slower than that of the nitrate ion. Using the modified resin, in spite of the presence of the sulfate ion, the nitrate ion was preferentially adsorbed from the mixture solution of the nitrate and sulfate ions. The adsorbed ions were desorbed from the resin by use of potassium perchlorate or perchloric acid solutions. With these procedures, it was possible that the nitrate ion in the sulfate ion, the amount of which was 200-fold that of the nitrate ion, was separated and determined by ion-chromatography. The enrichment of nitrate ions to 50-fold its original concentration was also possible.
Keywords : modification of anion exchange resin; separation; enrichment; nitrate ion; sulfate ion.
Motoyuki Yamagami, Masahiro Nonoguchi, Takashi Yamada, Takashi Shoji, Tadashi Utaka*1, Yoshihiro Mori*2, Shigeaki Nomura*3, Kazuo Taniguchi*4, Hisanobu Wakita*5 and Shigerou Ikeda*6
*1 X-ray Research Laboratory, Rigaku Corporation, 14-8, Akaoji-cho, Takatsuki-shi, Osaka 569-1146
*2 Advanced Technology Research Laboratories, Nippon Steel Corporation, c/o NSC Electron Corporation, 3434, Shimata, Hikari-shi, Yamaguchi 743-0063
*3 Junior College of Electronics Information, Osaka Electro-Communication University, 18-8, Hatsu-cho, Neyagawa-shi, Osaka 572-8530
*4 Department of Materials Science, Faculty of Engineering, Osaka Electro-Communication University, 18-8, Hatsu-cho, Neyagawa-shi, Osaka 572-8530
*5 Department of Chemistry, Faculty of Science, Fukuoka University, 8-19-1, Nanakuma, Jonan-ku, Fukuoka 814-0180
*6 SR Center, Ritsumeikan University, 1-1-1, Kusatsu-shi, Shiga 525-8577
A combination of vapor-phase decomposition (VPD) and total reflection X-ray fluorescence (TXRF), VPD/TXRF, was used for measuring trace elements of Na and Al. A TXRF measurement using W-Mα line was carried out for a highly sensitivity analysis of ultra trace light elements. The technique of VPD/TXRF combining W-Mα excitation could clearly detect the peaks for a sample at a level of 1011 atoms cm-2 that conventional TXRF could not have detected. In the case of 150 mm Si wafers, the lower limits of detection (LLDs) were found to be 3×1010 atoms cm-2 and 2×109 atoms cm-2 for Na and Al, respectively. The LLDs were improved by two orders of magnitude compared with those of TXRF without using the VPD treatment. The results obtained by VPD/TXRF were cross-checked with the one obtained by AAS. Both values were in good agreement. The glancing-angle dependence of the TXRF intensity was investigated on the samples before and after undergoing the VPD treatment. This dependence proves that the sample after a VPD treatment is the particle type on the wafer.
Keywords : total reflection X-ray fluorescence; vapor-phase decomposition; light element; ultra trace analysis; semiconductor.
Yuka Ezoe*1, *4, Akiko Takatsu, Takayoshi Kuroiwa*2, Sakae Eyama*3 and Akira Uchiumi*2
*1 Graduate School of Environmental Sciences, University of Tsukuba, 1-1-1, Tennoudai, Tsukuba-shi, Ibaraki 305-8577
*2 National Institute of Materials and Chemical Research, 1-1, Higashi, Tsukuba-shi, Ibaraki 305-8565
*3 Hikarikoke Inc., 2-10-1, Tanakamae, Kesennuma-shi, Miyagi 988-0053
*4 Present address; Department of Chemistry and Physics on Condensed Matter, Graduate School of Sciences, Kyushu University, 4-2-1, Ropponmatsu, Chuo-ku, Fukuoka 810-8560
A method for the determination of trace levels of Al in biological materials (fish) by graphite-furnace AAS was studied. Samples were digested with HNO3, since HClO4 gave great interferences to the determination of Al. The analytical wavelength was selected at 394.4 nm, and the ashing and atomizing temperatures were fixed at 1500°C and 2600°C, respectively. Interferences of coexisting inorganic components (Ca, Na, K, Mg, Fe and P) were also studied. The torelable concentrations for respective components were as follows: Ca 500 mg dm-3, Na 50 mg dm-3, K 50 mg dm-3, Mg 100 mg dm-3, Fe 20 mg dm-3 and P 200 mg dm-3. Prior to the Al analysis, samples should be diluted with water in order that the concentration of each inorganic component be lower than that mentioned above. In all standard and sample solutions the concentration of HNO3 were maintained in 0.1%(v/v). The Al concentrations in biological reference materials (NRCC DORM-2 and DOLT-2) determined by the present method agreed well with the reported reference values. The detection limit (3σ) was 1 ng g-1 (dry weight of biological samples). The present method is applicable with high accuracy and sensitivity to the determination of Al in biological samples.
Keywords : aluminium; graphite-furnace AAS; biological materials (fish).
Kazuko Yamamoto, Hideyuki Sakamoto, Masako Nishimura, Akira Yonetani and Toshihiro Shirasaki*
*Techno-research Laboratory, Hitachi Science Systems Co., Ltd., 882, Ichige, Hitachinaka-shi, Ibaraki 312-8504
(Received 15 July 1999, Accepted 19 August 1999)A chemical modifier was studied to analyze selenium in enteral formulas and urine samples using graphite-furnace AAS. Pd(1000 mg/l)+Mg(1000 mg/l)+citric acid (20%) was proper for the chemical modifier. NIST SRM 1549 (Non-Fat Milk Powder) and NIST SRM 2670 (Toxic Metals in Freeze-Dried Urine) were analyzed by this method; the results met the guaranteed values within the range of the analytical error. The detection limit (concentration corresponding to 3σ of the absorbance of the blank) by this method was 0.32 µg/l, and the repeatability of the absorbance with a concentration of 20 µg/l was 2% (n=5).
Keywords : selenium; enteral formulas; urine; chemical modifier; palladium; magnesium; citric acid; graphite-furnace AAS.
Hiroto Ozaki
Kaneka Techno Research Co., Ltd., 1-2-80, Yoshida-cho, Hyogo-ku, Kobe 652-0872
(Awarded by Kyoto University dated March 23, 1998)In this thesis, the author reports further developed techniques of MEKC; use of polymer surfactants as pseudo-stationary phases and direct coupling between MEKC and MS. If we can develop new pseudo-stationary phases having advantages over conventional monomer surfactants, MEKC will be a more useful and powerful separation technique. One purpose of this thesis was a basic study of amphiphilic copolymers as pseudo-stationary phases in MEKC. Polymer surfactants are promising pseudo-stationary phases for the direct coupling of the conventional MEKC with ESI-MS without special devices. Another purpose of this thesis was a basic study of the on-line coupling of the conventional MEKC with ESI-MS using polymer surfactants. Several advantages of polymer surfactants, including zero CMC, unique selectivity, and MS detection, were verified and polymer surfactants were given a place in the practical and useful pseudo-stationary phase for MEKC. Several techniques presented in this thesis for MEKC-MS include ESI using polymer surfactants as pseudo-stationary phase and ESI combined with the partial filling technique. Each technique gave promising results in this field.
(Received July 15, 1999)Keywords : micellar electrokinetic chromatography; polymer surfactant; amphiphilic copolymer; electrospray ionization; mass spectrometry; on-line analysis.
Yoshihide Tanaka
Department of Analytical Chemistry, Kawanishi Pharma Research Institute, Nippon Boehringer Ingelheim Co., Ltd., 3-10-1, Yato, Kawanishi-shi, Hyogo 666-0193
(Awarded by Kyoto University dated November 24, 1998)Enantiomeric separation of chiral drugs was investigated by capillary electrophoresis (CE) with various chiral selectors. When a protein was used as a chiral selector, UV absorption of the protein itself disturbed the detection of analytes. In order to overcome this drawback, a partial-filling technique was developed. A high protein concentration was used without causing low detection sensitivity. Various enantiomeric separations were successfully obtained using the partial-filling technique as well as several proteins, such as egg-white avidin and α1-acid glycoprotein. Additionally, the change in enantioselectivity of avidin by the addition of d-biotin was investigated. On the other hand, several ionic cyclodextrin derivatives were effective as chiral selectors for various enantiomeric separations without the partial-filling technique. The analytes were classified into three groups according to the separation conditions, and the classification was useful for optimizing the separation conditions. The partial-filling technique was useful for enantiomeric separations by capillary electrophoresis/mass spectrometry (CE/MS) using proteins and cyclodextrins as chiral selectors. The introduction of nonvolatile chiral selectors into the MS instrument was diminished by this technique. These methods, CE and CE/MS, were applied for optical purity tests of chiral drugs and enantiomeric separation of chiral drugs in human plasma.
(Received July 23, 1999)Keywords : enantiomeric separation; capillary electrophoresis; mass spectrometry; partial-filling technique; protein; cyclodextrin.
Shiro Matsuoka
Division of Analytical Chemistry, Department of Chemistry and Physics on Condensed Matter, Graduate School of Sciences, Kyushu University, 4-2-1, Ropponmatsu, Chuo-ku, Fukuoka 810-8560
(Awarded by Kyushu University dated February 23, 1998)The applicability of solid-phase spectrometry to flow analysis has been studied for the sensitive determination of target trace elements in natural-water samples. By a fundamental study involving light measurements, it has been confirmed that Beer's law can be applied to around the 4 to 5 absorbance scale in a solid particle layer system. Lambert's law was also confirmed up to a cell length of 4 cm if the Pt tube cell was used. On the basis of obtained data, a flow-through cell packed with fine spherical beads has been tested as a detector in flow-analysis systems for the sensitive determination of some elements such as cobalt(II), chromium, copper(II), molybdenum (VI) and vanadium as well as some rare earth elements and aluminium. By only using a few cm3 of the sample solution, the proposed method enabled us to determine the target chemical species present at µg dm-3 or lower levels in 3-6 samples in less than 1 hour. By a practical application of the proposed method to natural-water analysis, some significant information, unavailable by other determination methods, could be obtained: for example, details on the oxidation states of chromium present at sub-µg dm-3 levels in natural water.
(Received August 24, 1999)Keywords : solid-phase spectrometry; flow analysis; trace elements; natural water.
Kazuko Mizuishi
The Tokyo Metropolitan Research Laboratory of Public Health, 3-24-1, Hyakunincho, Shinjuku-ku, Tokyo 169-0073
(Awarded by Tokyo Metropolitan University dated March 31, 1998)A gas chromatographic method of analysis of trace and highly polar organotin compounds is problematic, and generally delivatization methods have been used. For a simple, accurate, selective and sensitive determination of organotin compounds in environmental samples, a direct GC analysis for organotin halides was studied. A GC method using a packed column pretreated with a hydrogen halide, such as hydrogen chloride (HCl) or hydrogen bromide (HBr), was first developed for the analysis of tributyltin (TBT) and triphenyltim (TPhT) chlorides. Then, the method was transferred to capillary-column separation. A method using an apolar capillary GC column and a flame photometric detector was developed for selective determination. Spiking of the column was carried out by doping a dilute methanolic HBr solution into the GC system prior to the injection of the standard or sample solution. The combination of the GC method developed to MS detection using SIM-NICI showed sufficient sensitivity to determine trace levels of TBT and TPhT in environmental aquatic samples. The direct GC procedure became a simpler, less time consuming, and very sensitive technique for the determination of organotin halides in environmental samples. This technique is also applicapable to the determination of other polar organometalic compounds. The direct determination of methyl mercury as a halide was established by the simple treatment of a GC column with dilute HBr solution.
(Received August 26, 1999)Keywords : organotin halides; ultratrace analysis; rapid analysis; non-derivatization; direct capillary GC; electron capture detection; NICI-MS.
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