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Volume 64, Issue 5
Displaying 1-9 of 9 articles from this issue
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Annual Topic “Bio” : Accounts
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Ryo ISHIHARA, Kazuki HASEGAWA, Kazuo HOSOKAWA, Mizuo MAEDAArticle type: Annual Topic “Bio” : Accounts
2015 Volume 64 Issue 5 Pages 319-328
Published: May 05, 2015
Released on J-STAGE: June 09, 2015
JOURNAL FREE ACCESSThe detection of early signs of diseases is essential to maintain the quality of life of human beings. Some proteins and nucleic acids known as biomarkers have potential to be "signs". As novel detection method, point-of-care tests (POCT) are of growing importance in various clinical fields, such as routine health assessment, predicting of disease risk, and monitoring disease progression. POCT has several requirements, such as high sensitivity, small sample volume, short detection time, and portability of the device. In various detection methods, some microfluidic device seems to be one of the promising methods for POCT, because it meets the requirements of POCT, except for portability. In this paper, we introduce our two technologies to overcome these drawbacks toward POCT. One is a power-free microfluidic device, which is driven by degassed poly(dimethylsiloxane), and thus eliminating the need for external power sources for fluid pumping. The other is laminar flow-assisted dendritic amplification, which enables on to improve the sensitivity of the device. The combination of these two techniques allowed us to detect sub-picomolar levels of protein biomarkers and several tens of femtomolar levels of nucleic acid biomarker in 20 min. The portability, rapidness, and high sensitivity of the device are ideal advantages for POCT.View full abstractDownload PDF (1233K)
Annual Topic “Bio” : Research Papers
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Nanako NISHIWAKI, Toshihiro KASAMA, Akihiko ISHIDA, Hirofumi TANI, Yos ...Article type: Annual Topic “Bio” : Research Papers
2015 Volume 64 Issue 5 Pages 329-335
Published: May 05, 2015
Released on J-STAGE: June 09, 2015
JOURNAL FREE ACCESSIn order to realize ultra-early diagnosis of disease in practical applications, we have fabricated next-generation immuno-pillar devices with higher sensitivity. In the newly developed devices, capture antibodies were immobilized on affinity beads based on chemical bonding, while in the previous-generation ones, polystyrene beads were used for physical adsorption-based immobilization. To evaluate the sensitivity of the next-generation immuno-pillar device, we quantitatively analyzed C-reactive protein (CRP). The limit of detection was estimated to be 0.1 ng mL−1 (total assay time, 23 min), which was twoorders of magnitude lower than that obtained by using the previous-generation immuno-pillar device, and was low enough to perform the CRP test. In addition, we investigated the storage stability of the immuno-pillar device, and confirmed that the device can retain its performance for over 9 months.View full abstractDownload PDF (1250K)
Annual Topic “Bio” : Analytical Reports
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Kenya HIGUCHI, Yuzuru OHKAWARAArticle type: Annual Topic “Bio” : Analytical Reports
2015 Volume 64 Issue 5 Pages 337-340
Published: May 05, 2015
Released on J-STAGE: June 09, 2015
JOURNAL FREE ACCESSUsing the same sample solution as the one adopted in the quantitative analysis of nitrate ion in lettuce, which we conducted by way of a prior verification of the analytical method stated herein, simultaneous determinations of potassium ion (K+), magnesium ion (Mg2+) and calcium ion (Ca2+) in lettuce were performed. The concentration of each of the said cations in the sample solution extracted from both leaf lettuce and head lettuce was determined by means of ion chromatography. As a result, the relative standard deviations of the quantitative values were all within five % for both leaf lettuce and head lettuce. Also, our adequacy evaluation of this analytical method (conducted in accordance with the "Guideline for the Adequacy Evaluation of Methods for Testing Metal Contents in Food" prescribed by the Ministry of Health, Labour and Welfare) found the trueness, repeatability and precision within the laboratory for each of the said cations to be: 108.6%, 1.3% and 12.6% for K+; 96.2%, 1.8% and 8.5% for Mg2+; and 104.0%, 1.8% and 5.7% for Ca2+ respectively, attaining the pertinent target values indicated in the said guideline. Based on the above, we deem this analytical method to be effective for determining the concentrations of K+, Mg2+ and Ca2+ in lettuce.View full abstractDownload PDF (539K)
Annual Topic “Gold” : Research Papers
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Wataru FUJISAKI, Yusuke SAWAKI, Tetsuya YOKOYAMA, Shinji YAMAMOTO, Shi ...Article type: Annual Topic “Gold” : Research Papers
2015 Volume 64 Issue 5 Pages 341-348
Published: May 05, 2015
Released on J-STAGE: June 09, 2015
JOURNAL FREE ACCESSThe cause of mass extinctions during the Phanerozoic period has been a long standing problem in geology. The large magmatic activity (CAMP: Central Atlantic Magmatic Province) associated with the breakup of Pangaea or a bolide impact event would have led the mass extinction at the Triassic–Jurassic (T–J) boundary. However, the cause of the mass extinction is still controversial because of insufficient geological evidences. In this study, we conducted detailed geological survey of the Inuyama area where good exposure of deep-sea sediments across the T–J boundary is observed. We collected rock samples bed-by-bed to analyze the abundances of platinum group elements (PGEs) with a high spatial resolution. Twenty-eight samples were powdered and spiked with 99Ru, 105Pd, 190Os, 191Ir, 194Pt. The sample was digested by a 2 : 1 mixture of HNO3 and HCl in a sealed Carious tube at 240°C for 48 hours. After chemical separation using an anion exchange resin, PGEs (except for Os) were measured by a quadrupole type inductively coupled plasma-mass spectrometry (ICP-MS). The PGEs concentrations were determined by the isotope dilution method. After solvent extraction with CCl4 and HBr, micro-distillation method was employed to purify Os. The Os isotopes were determined by Negative-Thermal Ionization Mass Spectrometry (N-TIMS). The relationship between Pd/Pt and Ir/Pt, as well as the PGE patterns, demonstrate that the high PGEs contents in shales can be explained by the incorporation of basaltic rocks supplied from CAMP. In addition, compared with fossil records, the highest PGE abundances (Os and Pd) are discovered from a shale just above the chert including the first appearance of Jurassic type radiolarian. These lines of evidence indicate that the CAMP volcanism would have contributed to the mass extinction at the T–J boundary.View full abstractDownload PDF (943K)
Research Papers
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Hiroka ARIGA, Miho TANAKAArticle type: Research Papers
2015 Volume 64 Issue 5 Pages 349-358
Published: May 05, 2015
Released on J-STAGE: June 09, 2015
JOURNAL FREE ACCESSSilicate and metal species with both positive and negative ions in solutions were examined by electrospray ionization mass spectrometry (ESI-MS). Comparing with detected species in chloride solutions of group-2 elements and transition metals (MCl2), and silicate solutions with MCl2, the reaction mechanism of the silicate and metal complexes through the ESI-MS was elucidated, and the information on their stability was obtained. In the positive ion, it was shown that in both MCl2 solutions and silicate solutions with MCl2 that bivalent transition metals (Mn, Fe, Co, Ni, Cu, Zn) were more easily hydrolyzed than group-2 elements (Mg, Ca, Sr, Ba). It was also confirmed that Ca2+ made the most stable complex with silicate ion among Mg2+, Ca2+, Sr2+ and Ba2+. Concerning the negative ion, Ca2+ and Na+ were found to make stable complexes with silicate. Furthermore, the stability of M2+ with silicate were examined by controlling the ionization conditions, such as the CDL temperature or the ESI probe voltage, for both positive and negative ions. The results showed that, the silicate complexes with Ca2+ and Na+ were identified by negative ions. These negative complexes are concluded to exist as they were as original species in the solutions. From these results, the stability between silicate and M2+ depends on their ionic size. Thus, Ca2+ and Na+ with silicate possess high stability.View full abstractDownload PDF (968K)
Technical Papers
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Hiroyuki NODA, Tateaki OGATA, Norio MANABEArticle type: Technical Papers
2015 Volume 64 Issue 5 Pages 359-362
Published: May 05, 2015
Released on J-STAGE: June 09, 2015
JOURNAL FREE ACCESSAn evaluation of the thermal-oxidation degree of poly(butylene terephthalate) [PBT] mold parts at practical temperatures was made by applying a fluorescence imaging method with a UV light excitation. Methyl 4-methoxybutyrate (MMB), based on the reactive pyrolysis-GC/MS method, was used as an index of the thermal-oxidation degree. The fluorescence intensities of the PBT mold parts increased with the increase of the thermal aging times at 120 – 180°C. The fluorescence intensities also increased with the increase of the amount of MMB. From the above results, it is suggested that this method can be used as a useful technique for evaluating the thermal-oxidation degree of PBT mold parts.View full abstractDownload PDF (867K) -
Tsuyoshi KANEKO, Hiroka NOJIMA, Yusuke SUZUKIArticle type: Technical Papers
2015 Volume 64 Issue 5 Pages 363-369
Published: May 05, 2015
Released on J-STAGE: June 09, 2015
JOURNAL FREE ACCESSA simple and rapid procedure was developed for the gas chromatographic analysis of vegetable oil involved in a crime. This procedure was performed using a syringe-type device. This device consists of a stainless-steel micro coil that is attached to a retractable plunger wire, which fits inside of a syringe needle housing. This device using a micro coil was called MCSD (Micro Coil Sampling Device), and was used as follows. In the first step, sampling was accomplished by dipping the end of the micro coil in a trace amount of oil, which was drawn into the micro coil by capillary action, and introducing it into the injection port of a gas chromatograph. Unsaponifiable constituents, such as sterols, could be detected by thermal desorption from the micro coil in the injection port. After thermal desorption, a GC/MS measurement of unsaponifiable constituents, a trimethylphenylammonium hydroxide solution was added to the remaining acylglycerols on a micro coil. Then, the micro coil was introduced into the injection port of the gas chromatograph to observe the fatty acid components by thermochemolysis with an esterification reagent. This procedure used MCSD could serve as a useful and powerful tool for forensic inspection of vegetable oil.View full abstractDownload PDF (1389K)
Analytical Reports
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Kazuya YANASE, Mayumi MATSUZAKI, Daichi SAWAMURA, Kazuyuki NAKAMURA, K ...Article type: Analytical Reports
2015 Volume 64 Issue 5 Pages 371-377
Published: May 05, 2015
Released on J-STAGE: June 09, 2015
JOURNAL FREE ACCESSAncient glass beads from the Epi-Jomon period, excavated from 7 archaeological sites in Hokkaido, were non-destructively analyzed by using a portable XRF spectrometer. The origin and distribution of the glass beads were analyzed based on their quantitative chemical compositions. The chemical compositions of glass beads from Hokkaido can be classified into two glass types based on their major components: i.e., potash silica glass type (K2O–SiO2) and soda lime silica glass (Na2O–CaO–SiO2). The heavy trace element compsitions of glass beads excavated from Hokkaido were basically similar to those excavated from the Kyushu region, Kanto region and Southeast Asia, as reported in our previous studies. From these results it has been found for the first time that glass beads exist with the same origin as those from Honshu distibuted in Hokkaido in Epi-Jomon period.View full abstractDownload PDF (1016K) -
Natsuhiko SUGIMURA, Takahiro YATSU, Yoko IGARASHI, Toshimichi SHIBUEArticle type: Analytical Reports
2015 Volume 64 Issue 5 Pages 379-383
Published: May 05, 2015
Released on J-STAGE: June 09, 2015
JOURNAL FREE ACCESSWe tested a practical method for reducing the error in computed the 29Si-NMR chemical shifts of sol-gel chemistry. Alkoxysiloxane oligomer Si[OSiMe(OMe)2]4 was employed as a reference compound of a density functional theory calculation (DFT). Tha alkoxysiloxane oligomer Si[OSiMe(OMe)2]4 is a symmetric molecular structure, which has two chemical shift values (−50 ppm, −100 ppm) of an important range for sol-gel chemistry. These two reference points could reduce any systematic errors of a DFT calculation for 29Si-NMR. The alkoxysiloxane oligomer reference method had a smaller DFT basis set dependence than did the tetramethylsilane reference method, and provided better root-mean-square errors.View full abstractDownload PDF (668K)
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