著者
Yuki IMURA Yasuyuki ASANO Kiichi SATO Etsuro YOSHIMURA
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.25, no.12, pp.1403-1407, 2009-12-10 (Released:2009-12-10)
参考文献数
16
被引用文献数
46 133

Intestinal absorption rates vary with the nature of the substances involved. In-vitro experiments with cell culture inserts are often conducted to evaluate the intestinal absorption rate. These inserts, however, require large amounts of cells, samples, and culture media, and take a long time to evaluate. To overcome these problems, we developed a microchip-based system that mimics the intestine. The microchip was composed of a glass slide, a permeable membrane, and polydimethylsiloxane (PDMS) sheets, which contained microchannels made by photolithography; Caco-2 cells were cultured on the membrane in the microchip. The system was regulated with a microsyringe pump. We conducted permeation tests; cyclophosphamide, which can permeate the intestinal barrier, displayed a high permeability coefficient and Lucifer yellow, which cannot be absorbed at the intestinal wall, displayed a low permeability coefficient. These results were consistent with those obtained using a conventional method, which supports the validity of our new system. The system realized an 80% reduction of cell consumption.
著者
LIU Xiaobo EICHENBERGER Michael FUJIOKA Yuuichiro DONG Jinhua UEDA Hiroshi
出版者
The Japan Society for Analytical Chemistry
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.28, no.9, pp.861-867, 2012
被引用文献数
10

The development of a rapid and specific assay for 17β-estradiol (E2) will accelerate its <i>in vitro</i> diagnostics and/or environmental pollution control. Here, we employed an open-sandwich (OS) selection scheme to improve the sensitivity for E2 in an OS immunoassay, which is based on antigen-dependent stabilization of the antibody (Ab) variable region, Fv, where the two domains (V<sub>H</sub> and V<sub>L</sub>) dissociated in the absence of an antigen. The V<sub>H</sub> domain of a cloned anti-E2 antibody displayed on M13 phage was randomly mutated, and after three OS biopanning rounds, a mutant that showed higher sensitivity in OS-ELISA for E2 was identified. Interestingly, compared with the wild-type V<sub>H</sub>, the cross-reactivity of the mutant was significantly decreased for the analogous steroid testosterone, both in OS and competitive ELISAs. This is the first report concerning selection for an anti-hapten Ab without using any hapten-carrier conjugates, and the method will be especially suitable for selecting Ab fragments that show better performance in hapten OS immunoassays.
著者
Nobuyuki TAKAYAMA Lee Wah LIM Toyohide TAKEUCHI
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.33, no.5, pp.631-634, 2017-05-10 (Released:2017-05-10)
参考文献数
19
被引用文献数
2

Zwitterionic monolithic columns were synthesized by a one-pot reaction using [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide, ethylene dimethacrylate, methanol and 2,2′-azobis(isobutyronitrile) as the monomer, cross-linker, porogen and initiator, respectively. The optimum conditions for polymerization and the efficiency of the prepared columns were examined for ion chromatography. The separation of five kinds of inorganic anions was achieved. The back pressures were monitored as increasing flow-rate, and the resulting plate heights (i.e. height equivalent of a theoretical plate, HETP) of SCN− were calculated at the inspected flow-rates. It was found that the increment rates of both the back pressure and HETP were rather slight. Mobile phases containing various cations or acid increased the retention times of the anions. Divalent cations could be separated, while monovalent cations could not be resolved due to their weak retention on the stationary phases.
著者
Tsutomu MIURA Kazuhiko HAYANO Kazushige NAKAYAMA
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.15, no.1, pp.23-28, 1999 (Released:2005-04-15)
参考文献数
12
被引用文献数
18 28

A determination method using an extraction chromatographic resin (EiChroM Sr.Spec™) has been developed for 210 Pb and 210 Po in environmental samples by alpha ray spectrometry. 210 Pb and 210 Po were coprecipitated simultaneously on CuS at pH 4.0 - 5.5. These nuclides were then adsorbed on a Sr.Spec™ resin column (0.79×4.0 cm) in 4 M HCl. The 210 Pb and 210 Po on the resin were eluted with 8 M HCl and 6 M HNO3, respectively. 210 Po was determined by alpha-ray spectrometry after plating on a stainless-steel disk. 210 Pb was determined as 210 Po produced from 210 Pb decay. The method was applied to soil (IAEA-326) and sediments (NIST-4354, IAEA-135, IAEA-368) standard reference materials, and the results agreed with their recommended values. The chemical yield of Po ranged from 56 to 99% and the yield of Pb was 95%. The detection limits of 210 Pb and 210 Po were 0.6 mBq/sample at a counting time of 70000 s.
著者
Takuma SUGI Etsuko OKUMURA Kaori KISO Ryuji IGARASHI
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.32, no.11, pp.1159-1164, 2016-11-10 (Released:2016-11-10)
参考文献数
29
被引用文献数
13

Withdrawal escape response of C. elegans to nonlocalized vibration is a useful behavioral paradigm to examine mechanisms underlying mechanosensory behavior and its memory-dependent change. However, there are very few methods for investigating the degree of vibration frequency, amplitude and duration needed to induce behavior and memory. Here, we establish a new system to quantify C. elegans mechanosensory behavior and memory using a piezoelectric sheet speaker. In the system, we can flexibly change the vibration properties at a nanoscale displacement level and quantify behavioral responses under each vibration property. This system is an economic setup and easily replicated in other laboratories. By using the system, we clearly detected withdrawal escape responses and confirmed habituation memory. This system will facilitate the understanding of physiological aspects of C. elegans mechanosensory behavior in the future.
著者
Shunsuke TOMITA Saki YOKOYAMA Ryoji KURITA Osamu NIWA Keitaro YOSHIMOTO
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.32, no.2, pp.237-240, 2016-02-10 (Released:2016-02-10)
参考文献数
27
被引用文献数
2 7

A cross-reactive sensor array consisting of polyion complexes (PICs) between anionic enzymes and poly(ethylene glycol)-modified (PEGylated) polyamines has been used to identify the source of mammalian sera. Although the catalytic activity of enzymes was inhibited by PIC formation with PEGylated polyamines, the subsequent addition of sera caused enzyme releases from PICs through competitive interactions between PICs and serum proteins, generating unique response patterns of changes in the enzyme activity. Linear discriminant analysis of the obtained patterns enabled the discrimination of five sera from different mammalian sources.
著者
Polona SMRKOLJ Vekoslava STIBILJ Ivan KREFT Emese KAPOLNA
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.21, no.12, pp.1501-1504, 2005 (Released:2006-02-24)
参考文献数
30
被引用文献数
22 38

Pumpkins were treated by spraying the leaves in the flowering period with a water solution containing 1.5 mg Se per liter in the form of Na2SeO4. The average total selenium content of seeds was found to be 0.19 µg g-1 in nontreated pumpkins and 1.1 µg g-1 in exposed ones. For speciation analysis, enzymatic hydrolysis with different amounts of Protease XIV was carried out. Under optimal conditions of enzymatic hydrolysis, 90% of the total selenium was found in soluble forms. Separation of species was performed using HPLC on anion and cation exchange columns and for detection UV-HG-AFS was applied. In enzymatic hydrolysis extracts, the main fraction of selenium was bound as selenomethionine (SeMet), representing on average of 81 ± 8% of the total Se content in the sample.
著者
Erina KOHYAMA Takao CHIKUMOTO Hiroyuki TADA Kiyoyuki KITAICHI Tadashi HORIUCHI Tetsuro ITO
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.32, no.8, pp.831-837, 2016-08-10 (Released:2016-08-10)
参考文献数
23
被引用文献数
19

Synthetic compounds structurally derived from the mild stimulant 2-amino-1-phenyl-1-propanone, known as cathinone derivatives, are one of the largest growing class of synthetic designer drugs. The characterization of these drugs is complicated by the structural diversity and similarity of compounds in the ever-growing cathinone family. This paper demonstrates the successful application of gas chromatography–electron ionization–tandem mass spectrometry (GC-EI-MS-MS) and liquid chromatography–photodiode array (LC-PDA) analysis to differentiate structurally similar derivatives including regioisomers of cathinones. Product ion spectrometry of iminium ions allows for an univocal differentiation of the studied cathinones with the same aminoalkyl moiety. Furthermore, the product ion spectrometry of acylium ions and ultraviolet spectra obtained by LC-PDA enabled differentiation of regioisomers resulting from different substitution patterns on the aromatic ring. The validity of the method was demonstrated by the analysis of N-alkylated ortho-, meta-, and para-alkylcathinones along with the scaffolds of buphedrones and pentiophenones.
著者
Yuki INOUE Yuta OKAZAKI Hitoshi MUGURUMA Hitoshi INOUE Tatsuya OHSAWA
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.32, no.7, pp.797-799, 2016-07-10 (Released:2016-07-10)
参考文献数
20
被引用文献数
2

Simultaneous electrochemical determination of nicotinamide adenine dinucleotide (NADH) and ascorbic acid (AA) at a carbon nanotube electrode is presented. The discrimination of NADH and AA is conducted with the difference of peak potential by differential pulse voltammetry. Two well-distinguished anodic peaks, +0.56 and +0.26 V, due to NADH and AA are observed. The characteristics of those peaks were independent from each other. The attained characteristics for simultaneous determination of NADH and AA are (i) NADH measurement at the concentration range of 0.030 – 2.0 mM in the presence of 1.2 mM AA, and (ii) AA measurement at the concentration range of 0.030 – 2.0 mM in the presence of 2.0 mM NADH.
著者
Wei WANG Shaozhong LUO Yaping CHEN Bo LI Masao HATTORI
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.32, no.6, pp.705-707, 2016-06-10 (Released:2016-06-10)
参考文献数
15
被引用文献数
7

An effective separation and simultaneous determination of corynoxeine and its metabolites using high-performance liquid chromatography with tandem mass spectrometry was developed and validated. The method was applied to pharmacokinetics and in vivo distribution investigations in rats after oral (0.105 mmol kg−1) and intravenous (0.0105 mmol kg−1) doses of corynoxeine. Its brain uptake index was of 3.08 × 10−11 mol g−1 at 3 h and 3.75 × 10−11 mol g−1 at 74 min after oral and intravenous doses, respectively.
著者
Shoji ISHIZAKA Jiang MA Terufumi FUJIWARA Kunihiro YAMAUCHI Noboru KITAMURA
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.32, no.4, pp.425-430, 2016-04-10 (Released:2016-04-10)
参考文献数
41
被引用文献数
11

Near-infrared laser-induced temperature elevation in single aqueous ammonium sulfate droplets levitated in air were evaluated by means of laser trapping and Raman spectroscopy. Since the vapor pressure in an aqueous solution droplet should be thermodynamically in equilibrium with that of water in air, the equilibrium size of the droplet varies sensitively through evaporation/condensation of water in accordance with the temperature change of the droplet. In this study, we demonstrated that the changes in the size of an optically levitated aqueous ammonium sulfate droplet were induced by irradiation of a 1064-nm laser beam as a heat source under an optical microscope. Temperature elevation in the droplet was evaluated successfully by means of Raman spectroscopy, and the values determined were shown to be in good agreement with those by the theoretical calculations based on the absorption coefficient of water at 1064-nm and the thermal conductivity of air. To the best of our knowledge, this is the first experimental demonstration showing that the absorption coefficient evaluated from changes in the size of optically-trapped aqueous droplets is consistent with that of pure water.
著者
Ahmed ALI Yasmine ABOULEILA Sara AMER Rie FURUSHIMA Samy EMARA Sebastien EQUIS Yann COTTE Tsutomu MASUJIMA
出版者
The Japan Society for Analytical Chemistry
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.32, no.2, pp.125-127, 2016-02-10 (Released:2016-02-10)
参考文献数
10
被引用文献数
12 38

The locations and volumes of the contents of a single HepG2 cell were visualized under three-dimensional (3D) holographic and tomographic (HT) laser microscopy, colored by refractive index, not staining. After trapping the specific area of a target cell in a nanospray tip, quantification was performed by live single-cell mass spectrometry. Comparison of the HepG2 cells’ before and after 3D-HT images allowed the inference of the precise volume and original location of the trapped cell contents. The total amount of a trapped molecule was estimated. The images also revealed morphological changes in the cell structure caused by the manipulation.
著者
Masaki TORIMURA Shinya KURATA Kazutaka YAMADA Toyokazu YOKOMAKU Yoichi KAMAGATA Takahiro KANAGAWA Ryuichiro KURANE
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.17, no.1, pp.155-160, 2001 (Released:2005-04-20)
参考文献数
48
被引用文献数
166 302

Fluorescently labeled oligonucleotide probes have been widely used in biotechnology, and fluorescence quenching by the interaction between the dyes and a nucleobase has been pointed out. This quenching causes big problem in analytical methods, but is useful in some other cases. Therefore, it is necessary to estimate the fluorescence quenching intensity under various conditions. We focused on the redox properties of some commercially available fluorescent dyes, and investigated dye-nucleotide interactions between a free dye and a nucleotide in aqueous solution by electrochemical and spectroscopic techniques. Our results suggested that the quenching was accompanied by photoinduced electron transfer between a thermodynamically quenchable excited dye and a specific base. Several kinds of fluorescent dyes labeled to the 5′-end of oligonucleotide C10T6 were prepared, and their quenching ratios compared upon hybridization with the complementary oligonucleotide A6G10. The quenching was completely reversible and their efficiencies depended on the attached fluorophore types. The fluorescence of 5-FAM, BODIPY FL or TAMRA-modified probe was strongly quenched by hybridization.
著者
Tsuyoshi ESAKI Tsutomu MASUJIMA
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.31, no.12, pp.1211-1213, 2015-12-10 (Released:2015-12-10)
参考文献数
12
被引用文献数
1 26

Mitochondria in a live HepG2 cell were visualized with a fluorescent probe to specify their location and state in a living cell. Then, mitochondria were selectively captured with a nanospray tip under fluorescence microscope, and thousands of small molecular peaks were revealed and unique steroids specific to mitochondria were also found. This fluorescence imaging combined with live single-cell mass spectrometry opens the door to the analysis of site- and state-specific molecular detection to elucidate precise molecular mechanisms at the single-cell and organelle level.
著者
Kanji MIYABE Ryohei TAKAHASHI Youki SHIMAZAKI
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.31, no.10, pp.1019-1025, 2015-10-10 (Released:2015-10-10)
参考文献数
40
被引用文献数
3 18

We developed moment analysis of affinity kinetics by chromatographic capillary electrophoresis (MKCCE) method for the kinetic study of intermolecular interactions. Association and dissociation rate constants of the interaction in a micellar electrokinetic chromatography (MEKC) system between thymol and sodium dodecylsulfate micelle were determined by the MKCCE method. It is a method based on the moment theory for the kinetic study of intermolecular interactions under the conditions that neither immobilization nor chemical modification of molecules is required. In CCE mode, experimental conditions are controlled so that the migration of solute-micelle complex is stopped and only solute molecules migrate in a capillary. Mass transfer behavior of solute molecules in the CCE system is analogous to that in a chromatographic system. However, because it was difficult in practice to really perform CE experiments under the CCE conditions, CE data were measured with changing experimental conditions, i.e., applied pressure, under the conditions that the migration velocity of solute-micelle complex was around zero. The rate constants could be analytically determined from the CE data. In the MKCCE method, it is not necessary to fit elution curves numerically calculated to those experimentally measured for the determination of the rate constants. Regarding the interaction between thymol and SDS micelles, association equilibrium constant and association and dissociation rate constants were determined as 6.35 × 103 dm3 mol−1, 5.6 × 104 dm3 mol−1 s−1, and 8.7 s−1, respectively. It was demonstrated that the MKCCE method was effective for the kinetic study of intermolecular interactions.
著者
Adelina SMIRNOVA Hisashi SHIMIZU Kazuma MAWATARI Takehiko KITAMORI
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.31, no.11, pp.1201-1204, 2015-11-10 (Released:2015-11-10)
参考文献数
15
被引用文献数
3 6

Micro- and nanofluidics has attracted much attention, particularly concerning single-cell analysis when small amounts of liquids are examined. In present work we successfully fabricated extended-nano channels that were more narrow and shorter (2 mm) as well as wider and longer (10 mm), and accomplished a reversed-phase HPLC separation of labeled amino acids on these channels after octadecylsilylation (ODS). The separation performance characteristics were compared for both types of nano spaces. At an equal amount of pressure, the longer extended-nano channels showed permeability that was one-order higher (K = 47 × 10−14 m2) and separation impedance (E = 13) that was one-order lower than that of the shorter version. Also, the separation plate number for the longer channel was 4000 with a plate height of 2.5 μm. Both channels have advantages for use in single-cell analysis. The longer channel can be applied for the separation of macromolecules (proteomics), while the short version is more applicable to small molecules (amino acids).
著者
Kazuhiro BAN Yoshihiro SAITO Kiyokatsu JINNO
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.20, no.10, pp.1403-1408, 2004 (Released:2005-02-18)
参考文献数
32
被引用文献数
14 20

The influence of the mobile-phase composition and temperature on the surface structure of the octadecylsilica (ODS) stationary-phase was investigated by applying a molecular-dynamics (MD) simulation. The molecular model to which the MD simulation was applied consisted of three parts: an amorphous silica base, dimethyloctadecylsilyl ligands and mobile-phase solvents. More detailed information on the effect of the mobile-phase composition was obtained by constructing larger molecular models than those used in our previous study. The thickness of the hydrocarbon layer of the stationary phase could be estimated based on the distance between the carbon atom located at the terminal end of the ODS ligand and the silica gel surface. The structural information obtained by the calculation showed good consistency with the experimentally observed values. The gauche fraction in the ODS ligand conformation could be also estimated to obtain a more detailed ligand conformation for each molecular model. It was found that as the temperature increased, the ligand conformation collapsed more. This trend was the same as the experimentally observed trends obtained by NMR, FT-IR, and Raman spectroscopic techniques.
著者
Masoumeh TABATABAEE Mohamad R. NATEGHI Seyed Jaml MOSAVI
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.22, no.12, pp.1601-1603, 2006 (Released:2006-12-12)
参考文献数
16
被引用文献数
6 7

A simple, rapid and sensitive method has been developed for determination of traces of silver(I) (0.2 - 13 ng mL-1) based on its catalytic effect on the oxidation of thionine by peroxodisulfate in the presence of 1 - 10 phenanthroline as an activator. The reaction is monitored spectrophotometrically by measuring the decrease in absorbance of thionine at 600 nm by the fixed time method. The detection limit is 0.098 ng mL-1 and the relative standard deviation for 0.5, 3.0, 5.0 and 10 ng ml-1 Ag(I) are 4.1, 1.37, 1.06 and 0.64%, respectively. The method is free from most interferences and it was applied to determination of silver in photographic solutions and well-water samples.
著者
Sakon RAHONG Takao YASUI Takeshi YANAGIDA Kazuki NAGASHIMA Masaki KANAI Gang MENG Yong HE Fuwei ZHUGE Noritada KAJI Tomoji KAWAI Yoshinobu BABA
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.31, no.3, pp.153-157, 2015-03-10 (Released:2015-03-10)
参考文献数
23
被引用文献数
3 12

Molecular filtration and purification play important roles for biomolecule analysis. However, it is still necessary to improve efficiency and reduce the filtration time. Here, we show self-assembled nanowire arrays as three-dimensional (3D) nanopores embedded in a microfluidic channel for ultrafast DNA filtration. The 3D nanopore structure was formed by a vapor-liquid-solid (VLS) nanowire growth technique, which allowed us to control pore size of the filtration material by varying the number of growth cycles. λ DNA molecules (48.5 kbp) were filtrated from a mixture of T4 DNA (166 kbp) at the entrance of the 3D nanopore structure within 1 s under an applied electric field. Moreover, we observed single DNA molecule migration of T4 and λ DNA molecules to clarify the filtration mechanism. The 3D nanopore structure has simplicity of fabrication, flexibility of pore size control and reusability for biomolecule filtration. Consequently it is an excellent material for biomolecular filtration.
著者
Keisuke MORITA Emiko KANEKO
出版者
(社)日本分析化学会
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.22, no.8, pp.1085-1089, 2006 (Released:2006-08-09)
参考文献数
37
被引用文献数
22 48

In this study, a simple and sensitive method for the determination of arsenic in water samples was developed. The method is based on the formation of micro particles of Ethyl Violet and molybdoarsenate, which gives an apparently homogeneous blue color to the solution. The absorption of the excess dye gradually decreases due to its conversion to a colorless carbinol species under strongly acidic conditions. Consequently, the sufficiently low reagent blank enables the spectrophotometric determination of arsenic with the detection limit of 4 µg l-1. The coefficient of variation for the spectrophotometry at 50 µg l-1 was 3.5% (n = 5). Furthermore, it is possible to detect concentrations as low as 10 µg l-1 of arsenic visually. Our method will be useful as a simple, rapid, and cost-effective field test of arsenic, requiring no complex apparatus or skilled laboratory support.