Vol. 47, No. 9
September, 1998
Norihiro Kobayashi and Junichi Goto*
*Faculty of Pharmaceutical Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai 980-8578
(Received 29 May 1998, Accepted 10 July 1998)An overview of immunoaffinity extraction, which is a highly selective and efficient sample pretreatment method in biomedical analyses, is given mainly from a practical aspect. Essential techniques for developing an extraction system, such as the production and immobilization of an antibody having suitable specificity, are described in detail. Some recent remarkable applications of immunoaffinity extraction, linked with an analytical procedure based on immunoassay or chromatography for determining hormones or drug metabolites in biological fluids, are also surveyed.
Keywords: immunoaffinity extraction; immunoaffinity chromatography; biomedical analysis; sample pretreatment; antibody production; antibody immobilization.
Yoshihide Tanaka, Yasuhiro Kishimoto*, Koji Otsuka and Shigeru Terabe**
* Department of Analytical Chemistry, Kawanishi Pharm Research Institute, Nippon Boehringer Ingelheim Co., Ltd., 3-10-1, Yato, Kawanishi-shi, Hyogo 666-0193
** Department of Material Science, Faculty of Science, Himeji Institute of Technology, 1475-2, Kanaji, Kamigori, Ako-gun, Hyogo 678-1297
Capillary electrophoresis/mass spectrometry (CE/MS) was applied to an analysis of surfactants. The detection limit of sodium dodecyl sulfate (SDS) was determined. Compared to indirect UV detection, SDS was detected with higher sensitivity by MS detection. The detection limit at a signal-to-noise ratio of 2 was 0.05 µg/ml when an untreated fused-silica capillary was used. Sodium decyl sulfate and sodium tetradecyl sulfate were detected by CE/MS as impurities in SDS. CE/MS easily showed a difference in purities of commercial SDS among three different suppliers. Composition analyses of commercial surfactants (sodium polyoxyethylene(2) dodecyl ether sulfate and dodecyl dimethylaminoacetic acid betaine) were also performed by CE/MS. A number of components and impurities were identified according to each molecular mass. It has been shown that CE/MS is a promising analytical tool for the analysis of surfactants.
Keywords: capillary electrophoresis; mass spectrometry; electrospray ionization; surfactant; impurity.
Naohito Yoshikawa*, Hisakuni Sato and Haruhiko Ohya**
* Sea Water Science Research Laboratory, The Salt Industry Center of Japan, 4-13-20, Sakawa, Odawara-shi, Kanagawa 256-0816
** Department of Material Science and Chemical Engineering, Faculty of Engineering, Yokohama National University, 79-5, Tokiwadai, Hodogaya-ku, Yokohama-shi, Kanagawa 240-0067
Since the sulfate ion is a main impurity contained in highly pure salt products manufactured through a dissolution purification process, controlling the sulfate-ion concentration of the process solutions is important regarding salt production. Furthermore, in the case of considering automation, the elimination of labor and optimization of the process, it is necessary to research and develop an in-line quantitative determination method. Thus, the authors carried out a study using an attenuated total-reflectance-IR (ATR-IR) method for a determination using SO degenerate stretching. As a result, this method could make an accurate determination of the sulfate ion of the process solutions possible by using a sodium chloride-saturated solution as a standard solution without any effects of the index of refraction and sample temperature. We therefore believe that it adapts a simple determination and an in-line determination of the process solutions.
Keywords: attenuated total reflectance-IR; sulfate ion; SO degenerate stretching; salt-manufacturing process; in-line determination.
Naohito Yoshikawa*, Hisakuni Sato and Haruhiko Ohya**
* Sea Water Science Research Laboratory, The Salt Industry Center of Japan, 4-13-20, Sakawa, Odawara-shi, Kanagawa 256-0816
** Department of Material Science and Chemical Engineering, Faculty of Engineering, Yokohama National University, 79-5, Tokiwadai, Hodogaya-ku, Yokohama-shi, Kanagawa 240-0067
Since the sulfate ion is a main impurity contained in highly pure salt products manufactured through a dissolution purification process, controlling the content of the sulfate ion in the salt products is important concerning the aspect of salt production. The authors studied a simple method for determining the sulfate ion content by IR diffuse reflectometry and, as a result, developed a simple determining method capable of determining the sulfate-ion content of highly pure salts without destruction and with a smaller determining error of around ±10 mgkg-1 and a higher repetition accuracy (RSD), of 4.6%. In this method, the peak strength of SO degenerate stretching vibrations specific to the sulfate ion, which was determined by IR diffuse reflectometry, is corrected using the variation of the K-M value of 1900-2090 cm-1 caused by effects of the filling condition, particle size and particle-size distribution of the test sample on the degree of light scattering; also, the effects of the ambient temperatures and humidity are corrected using the absolute humidity. This method has sufficient accuracy for a simple determination, which enables a sulfate ion determination within a short time of approximately one minute, and is therefore, considered, to be thoroughly adaptable to product and process control.
Keywords: IR diffuse reflectometry; sulfate ion; rapid and simple determination; SO degenerate stretching; salt-manufacturing process.
Toshiaki Nomura, Shigeri Inanobe and Hiroshi Fujita*
*Department of Chemistry, Faculty of Science, Shinshu University, 3-1-1, Asahi, Matsumoto-shi, Nagano 390-8621
(Received 30 March 1998, Accepted 29 May 1998)A twinned piezoelectric quartz crystal (PQC) was constructed with two quartz crystals having one electrode (QC) which contacted with liquids on the other side. A twinned PQC having no counter electrode, that is, two electrodes were connected to an oscillator, oscillated with a resonance frequency. A twinned PQC having counter electrode of a wire or plate connected to two oscillators oscillated each other. The frequencies of these twinned PQCs depended upon the properties of the liquids, as did the mass change on the QC as an electrode-separated PQC. The twinned PQC could be used as detectors for the liquid properties and the deposited mass, that is, chemical analysis. Especially the twinned PQC could be used for a detector of chemical analysis under changing conditions of the solution properties and temperature by measuring the frequency difference between the frequency of the QC, which deposited the analyte, and the frequency of the other QC, which did not.
Keywords: twinned piezoelectric quartz crystal; chemical analysis; frequency change; solution properties; adsorption.
Susumu Ichinoki, Mitsuru Yamazaki, Emi Ogawa, Mayumi Kashihara and Junko Ishizaki*
*Faculty of Pharmaceutical Sciences, Hokuriku University, Ho 3, Kanagawa-machi, Kanazawa, Ishikawa 920-1181
(Received 27 February 1998, Accepted 2 June 1998)In reversed-phase HPLC, acetonitrile and chlorinated organic solvents, such as chloroform, are often used as a major organic component and an organic modifier of the mobile phase, respectively. However, the solvents usually damage the environment and require specific waste treatment compared with non-chlorinated compounds. In this work, several aliphatic alcohols were investigated as mobile-phase components for the separation of polyaromatic hydrocarbons (PAHs) with a C18 column and compared with the results of acetonitrile and chloroform; they were then evaluated concerning the column efficiency, analysis time, and effect on the elution order of some PAHs. It was found that methanol is a good solvent as a major component of the mobile phase concerning the column efficiency and ability to perform elution control. Octanol and decanol have enabled a change in the elution order of acenaphthene and triptycene as well as chloroform. Thus, aliphatic alcohols can be used instead of acetonitrile or chloroform with excellent properties.
Keywords: aliphatic alcohols as eluent component; reversed-phase HPLC; comparison of acetonitrile and methanol; effect of 1-hexanol and 1-octanol on elution behavior of polyalomatic hydrocarbons.
Hiroaki Kubo, Masatoshi Saitoh, Yuko Mochii, Akira Toriba*, Takashi Nishikawa**, Tomoko Inomata, Yoshihiro Yoshimura and Hiroyuki Nakazawa***
*School of Pharmaceutical Sciences, Kitasato University, 5-9-l, Shirokane, Minato, Tokyo l08-0072
**School of Medicine, Kitasato University, 1-15-1, Kitasato, Sagamihara-shi, Kanagawa 228-0829
***Faculty of Pharmaceutical Science, Hoshi University, 2-4-41, Ebara, Shinagawa, Tokyo 142-8501
The chemiluminescence reaction of luminol with reducing agents was studied by a flow-injection analysis. We found that reducing agents directly produce a chemiluminescence with luminol in the presence of hexacyanoferrate(III) and hexacyanoferrate(II) as a catalyst in an alkaline solution. To explain the chemiluminescence of luminol with reducing agents, ESR measurements were performed. ESR showed that superoxide anion radicals were generated from uric acid, dihydroxyacetone, hydroxylamine, cortisone and glucose in an alkaline solution by using 5,5'-dimethyl-1-pyrroline N-oxide (DMPO) as a spin-trap agent. The ascorbate radical was observed for ascorbic acid without DMPO. For phenacyl alcohol, a new radical without DMPO was observed. It is reported that the superoxide anion radical is a crucial intermediate in luminol chemiluminescence and that the chemiluminescence is generated in the presence of free radicals. Therefore, it was suggested that these radicals resulted from the reducing agents in the alkaline solution participate in luminol chemiluminescence. The detection limits (S/N=3) of uric acid, phenacyl alcohol, hydroxylamine, ascorbic acid, dihydroxyacetone, cortisone and glucose were 40, 60, 70, 200, 430, 440 and 75 ng, respectively.
Keywords: chemiluminescence; ESR; flow injection analysis; luminol; reducing agents.
Kunihiro Watanabe, Satoshi Abe and Masayuki Itagaki*
*Department of Industrial Chemistry, Faculty of Science and Technology, Science University of Tokyo, 2641, Yamazaki, Noda-shi, Chiba 278-8510
(Received 19 March 1998, Accepted 6 June 1998)Bipyridyl (bipy) is an excellent chelate reagent for gallium(III) determination by fluorometry because of its weaker fluorescence intensity compared with that of the Ga-bipy complex obtained in the presence of excess reagent. However, the Ga(III)-bipy complex was unstable concerning its fluorescence intensity, which was affected remarkably at temperatures above the expected effect. Therefore, the effect of temperature was investigated by a flow injection analysis with fluorescence and absorbance detectors. As a result, it was found that the Ga(III)-bipy complex could be formed instantly after mixing Ga(III) and bipy solutions; the Ga(III) complex then decomposed according to the standing time. The reaction of Ga(III) complex decomposition reached equilibrium after about 30min at room temperature. Since the decomposition rate of the complex was affected by the temperature, the fluorescence intensity of the Ga(III)-bipy complex was varied by the standing time and temperature. The effect of temperature on the fluorescence intensity of the Ga(III)-bipy complex was larger than that of the Ga(III) complex obtained with 1,10-phenanthroline(phen), similar to bipy having the N,N coordination. The result could be explained by the difference in the structure between bipy and phen. Their structures and energies were calculated by MOPAC. The result showed that the stability of the Ga(III) complex is affected by the structure of the ligand. The properties of the Ga(III)-bipy complex were examined in order to develop a high-sensitivity fluorometry of Ga. The fluorescence intensity of the Ga(III)-bipy complex was enhanced by 2.6 times by the addition of a surfactant (SDS). The properties of the Ga(III)-bipy complex in aqueous solution in the presence of SDS were as follows: fluorescence quantum yield, 0.12; fluorescence lifetime, 1.2 ns; natural radiative lifetime, 8.6 ns; fluorescence emission rate constant (1.16×108 s-1), and a radiationless transition rate constant of 8.84×108 s-1. The detection limit of Ga decreased to 1/1000 using the proposed method compared with that with phen.
Keywords: 2,2'-bipyridyl; 1,10-phenanthroline; gallium; MOPAC; fluorescence properties.
Chushiro Yonezawa, Shigeju Ichimura*, Tatsuya Kurosawa** and Hideaki Matsue*
*Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki 319-1195
**Radiation Application Development Association, Tokai-mura, Naka-gun, Ibaraki 319-1106
An analytical basis for a neutron-activation analysis (NAA) for measuring nuclides of second-order half-life produced by the (n, γ) reaction has been studied using a neutron-activation analysis facility (PN-3) of JRR-3M. The NAA facility, comprising a fast pneumatic irradiation system and a high count-rate gamma-ray spectrometer, is able to automatically conduct NAA with short-lived nuclides. Basic experimental conditions, such as a high count-rate gamma-ray measurement, the effects of irradiation-capsule material and the stability of the neutron flux, were examined. The analytical sensitivities and detection limits for 20 elements of which activated radionuclide having half-lifes from 0.7 to 100 s were obtained. Scandium, In, Dy and Hf were elements having the highest analytical sensitivity, with detection limits down to 4.2 to 14 ng. Fluorine, which is difficult to determine by other methods, can be detected at above 530 ng. Analytical applications of NAA with short-lived nuclides have been carried out for F, Se, Sc, Hf, In and Dy in various materials, including reference materials. The accuracy, precision and detection limits of NAA with short-lived nuclides have been evaluated.
Keywords : NAA with short-lived nuclides; second-order half-life; basic study; NAA facility; JRR-3M; analytical sensitivity; detection limit; reference materials.
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