Vol. 15, Supplement A (1999)

Proceedings of the 28th Chemical Sensor Symposium
March 31-April 2, 1999

Abstracts

1.

Naイオン伝導体を用いた塩素ガスセンサの応答性
青野宏通、松下善一、定岡芳彦

愛媛大工

EMF RESPONSES OF Cl2 GAS SENSOR USING Na+ CONDUCTING SOLID ELECTROLYTE
Hiromichi AONO, Yoshikazu MATSUSHITA, and Yoshihiko SADAOKA

Department of Materials Science and Engineering, Faculty of Engineering, Ehime University
Matsuyama-shi, Ehime, 790-8577, Japan

The EMF (electromotive force) responses were investigated for a Cl2 gas sensor using a composite Na+ conductor, i. e., polycrystalline NASICON and glassy Na2O-Al2O3-4SiO2 (40 wt%). The mechanical strength and the densification were improved by the addition of the glassy material. The probe using the composite electrolyte and RuO2+NaCl (1:1) measuring electrode gave rapid EMF change even for Cl2 gas concentration lower than 10 ppm. The EMF values were not influenced by the change of O2 and CO2 gas concentrations.

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2.

ゲルマニウム酸塩を母体とした固体電解質によるアンモニアガスの検出

今中信人、吉川せんり、山本貴生、田村真治、足立吟也

阪大院工

AMMONIA GAS SENSING WITH SOLID ELECTROLYTES BASED ON AMMONIUM HYDROGERMANATE

Nobuhito IMANAKA, Senri YOSHIKAWA, Takao YAMAMOTO, Shinji TAMURA and Gin-ya ADACHI

Department of Applied Chemistry, Faculty of Engineering, Osaka University
2-1 Yamadaoka, Suita, Osaka 565-0871, Japan

The solid electrolyte based on ammonium hydrogermanate in which the germanium site was partially replaced by phosphor was synthesized by a hydrothermal method and the ammonia gas sensing characteristics with the electrolyte were investigated by constructing an ammonia gas concentration cell at the temperature as low as 100℃. The EMF output of the cell changed immediately after the NH3 gas variation and the time necessary to attain for the 90% response was about 3 min including the gas substitution period. The response was reproducible and exactly obeyed the Nernst equation.

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3.

PbSnF4を用いた常温作動型CO2センサ

椎原　一、後藤郁夫、江口ゆかり、吉田和昭、石原達己、滝田祐作、武内　隆

大分大工

CO2 GAS SENSOR CONSISTING OF PbSnF4 AND METAL CARBONATES OPERABLE AT NORMAL TEMPERATURE

Hajime SHIIHARA, Ikuo GOTO, Yukari EGUCHI, Kazuaki YOSHIDA, Tatumi ISHIHARA, Yusaku TAKITA and Takashi TAKEUCHI

Department of Applied Chemistry, Faculty of engineering, Oita University
700 Dannoharu, Oita 870-1192, Japan

The potentiometric CO2 gas sensors composed of PbSnF4 as solid electrolyte and metal carbonates as auxiliary phase were proposed and examined. Several metal carbonates and metal oxide additives were tested but most of them did not respond to CO2 gases. The only addition of CuO to Na2CO3 made the sensor respondent to CO2 at normal temperature. The emf dependence of the sensor on CO2 concentration was measured. The interference effect of CO and isobutane was also examined and found to be negligible.

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4.

基準物質を必要としない起電力式水蒸気センサ

片平幸司、岩原弘育、小出邦博*

名大理工総研・株式会社TYK*

GALVANIC CELL TYPE HIGH TEMPERATURE STEAM SENSOR WITHOUT STANDARD MATERIAL

Koji KATAHIRA, Hiroyasu IWAHARA and Kunihiro KOIDE*

Center for Integrated Research in Science and Engineering, Nagoya University
Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
*TYK Corporation, Advanced Materials Research & Development Center
3-1 Ohbata-cho, Tajimi, 507-8607, Japan

Galvanic cell type high temperature steam sensor without standard material was constructed using a proton conducting CaZr0.9In0.1O3-αceramic as a solid electrolyte. A sensor of this type consists of two electrochemical cells which contact tightly each other ; one cell with constant voltage or current is for a hydrogen pump to keep the hydrogen pressure in contact interface constant and another cell is for a sensing of hydrogen activity in the test gas using hydrogen gas from hydrogen pump as a standard gas. This sensor showed good response to water vapor at elevated temperature with small pumping current less than 1 mA.

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5.

基準物質を必要としない起電力式炭酸ガスセンサ

栗林　誠、松本広重、片平幸司、岩原弘育

名大理工総研

GALVANIC-CELL-TYPE CO2 SENSOR WITHOUT USING THE STANDARD MATERIAL

Makoto KURIBAYASHI, Hiroshige MATSUMOTO, Koji KATAHIRA and Hiroyasu IWAHARA

Center for Integrated Research in Science and Engineering, Nagoya University
Furo-cho, Chikusa, Nagoya 464-8603, Japan

A galvanic-cell-type CO2 sensor using molten carbonate as an electrolyte was examined. In order to prevent the use of external standard gas, one additional cell for electrochemical pumping of CO2 and O2 was attached to the sensor cell. The pumping cell supplies CO2 and O2 by 2:1 from ambient atmosphere to the reference electrode compartment of the sensing cell. In the CO2 sensor with such two-cell configuration, the sensing cell showed almost constant voltage independent of the pumping current. The EMF fairly agreed with that calculated for the reference atmosphere as 2/3 atm CO2 and 1/3 atm O2, indicating that the pumping cell could control the activities of CO2 and O2 in the reference compartment of the sensor cell.

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6.

各種電極を用いた限界電流式ハイドロカーボンセンサ
渡邉慎吾、波多野吉保、江口ゆかり、吉田和昭、石原達己、滝田祐作、武内　隆

大分大工

LIMITING CURRENT TYPE HYDROCARBON SENSORS WITH VARIOUS ELECTRODE MATERIALS

Shingo WATANABE, Yoshiyasu HATANO, Yukari EGUCHI, Kazuaki YOSHIDA, Tatumi ISHIHARA, Yusaku TAKITA and Takashi TAKEUCHI

Department of Applied Chemistry, Faculty of Engineering, Oita University
700 Dannoharu, Oita 870-1192, Japan

A limiting current type hydrocarbon sensor composed of yttria stabilized zirconia (YSZ) as a solid electrolyte and two electrodes in a cell and operating at the second step of limiting current was proposed previously. To improve the sensor, various combinations of the electrode materials have been examined in this study. Among the combinations of the electrode materials examined, i.e. Au-Ag, Au-Pt, Au-Pd, Pd-Pt, Pd-Ag, the combination Au-Ag showed the highest sensitivity and stability.

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7.

混成電位型炭化水素センサにおける金電極の修飾

日比野高士、柿元志朗*、佐野　充*

名工研、名大院人情*

MIXED POTENTIALS FOR HYDROCARBON GASES AT VARIOUS MODIFIED GOLD ELECTRODES

Takashi HIBINO, Shiro KAKIMOTO* and Mitsuru SANO*

National Industrial Research Institute of Nagoya
Hirate-cho, Kita-ku, Nagoya 462-8510, Japan
*Graduate School of Human Informatics, Nagoya University
Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan

It was found that the non-Nernstian behaviors of a stabilized zirconia cell using an Au working electrode for saturated and unsaturated hydrocarbon gases can be markedly enhanced by adding Ta2O5 oxide to the Au electrode. The non-ideal EMF value of the cell using the 10 wt% Ta2O5-added Au electrode for propene is typically 3 times the value of the cell using the parent Au electrode. The enhancing effect is explained by a promotion of the anodic reaction of propene in preference to the cathodic reaction of oxygen, which simultaneously occur at the working electrode. The non-ideal EMF value for hydrocarbons becomes more nagative as their carbon number increases, their C - C linkage is unsaturated and their chaing structure is branched.

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8.

金／安定化ジルコニア系での一酸化炭素を含む非平衡ガスの電極反応

　 水崎純一郎，川田達也，開米篤志，二唐　裕，河村憲一，松本弘樹

東北大科研

GAS ELECTRODE REACTION AT THE GOLD/STABILIZED ZIRCONIA SYSTEM IN NONEQUILIBRIUM GAS-MIXTURES WITH CARBON MONO-OXIDE

Junichiro MIZUSAKI, Tatsuya KAWADA, Atsushi KAIMAI, Yutaka NIGARA, Junichi KAWAMURA, and Hiroki MATSUMOTO

Research Institute for Scientific Measurements, Tohoku University
2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan

Although many reports have been published on the gas-sensing properties of Au electrode on stabilized zirconia, SZ, the reported gaseous species selectively detected by this electrode system are in variety. To approach the gas-sensing mechanism of this electrode system, using the cells:test gas (O2, CO, CO2, H2, H2O, Ar), porous Au / SZ / porous Pt, reference gas (O2-Ar). EMF and steady-state polarization curves were measured with various combinations of test gas species in nonequilibrium. It was found that small amount of CO in O2-Ar gas mixtures causes large deviation in EMF while H2 and other gases do not. However, the EMF deviation caused by CO in O2-Ar gas-mixtures was found reduced by adding a small amount of H2. Some concerted reaction among CO and H2-H2O components on Au surface was suggested which could not be explained by a simple mixed potential theorem of summation of polarization curves.

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9.

酸化チタンの固体電子構造
松嶋茂憲，小林健吉郎*，香山正憲**

北九州高専，静岡大工*，大工研**

ENERGY BAND CALCULATION OF TITANIUM DIOXIDE
Shigenori MATSUSHIMA, Kenkichiro KOBAYASHI* and Masanori KOHYAMA**

Department of Chemical Engineering, Kitakyushu National College of Technology
5-20-1, Shii, Kokuraminami-ku, Kitakyushu, Fukuoka 803, Japan
*Department of Materials Science and Technology, Faculty of Engineering, Shizuoka University
5-1, Jyohoku 3 choume, Hamamatsu, Shizuoka 432, Japan
**Department of Material Physics, Osaka National Research Institute
1-8-31, Midorigaoka, Ikeda, Osaka 563, Japan

The electronic structure of TiO2 is calculated by using a semi-empirical tight binding method. If only Ti-O interaction is retained in the calculation, a top of the valence band is es- sentially flat in k-space. Compared with experimental results, the band gap is wide and the va- lence band is narrow. Therefore, the O-O and Ti-Ti interactions are included. From a density of state analysis, it is found that the valence and the conduction bands are mainly composed of Ti-3d and O-2p orbitals. The conduction band can be divided into two distinct regions because of an octahedral ligand field. Further, we attempt the first-principle band calculation by using a personal computer to investigate the charge distribution on TiO2 (110) plane.

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10.

ダイヤモンド薄膜による半導体材料ガスの検知
高田義、福永徹也、林和志*、横田嘉弘*、橘武史*、宮田浩一*、小橋宏司*

新コスモス電機、神戸製鋼所*

BORON-DOPED DIAMOND THIN FILM SENSOR FOR DETECTION OF VARIOUS SEMICONDUCTOR MANUFACTURING GASES
Tadashi TAKADA,Tetsuya FUKUNAGA,Kazushi HAYASHI*,Yoshihiro YOKOTA*, Takeshi TACHIBANA*,Koichi MIYATA* and Koji OBASHI*

New Cosmos Electric Co.,Ltd.
2-5-4 Mitsuya-naka,Yodogawa-ku,Osaka 532-0032, Japan
*Kobe Steel ,Ltd.
1-5-5 Takatsukadai,Nishi-ku,Kobe,Hyogo,651-2271, Japan

Gas sensing characteristics of B-doped polycrystalline diamond thin films were examined, especially to detection of various toxic gases used in semiconductor manufacturing process. It was found that after the diamond thin films with 1-6×1018 cm-3 of B-concentration and 3-5μm of grain size were treated at 600-700℃ for 30 min, they became highly sensitive to extremely low concentration of the toxic gases such as PH3 (100-300ppb), B2H6 (100ppb), AsH3 (50ppb), GeH4 (200ppb) and SiH4 (5ppm).

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j1.

半導体式ニオイセンサの開発及び実用化

高田義、福井清、鈴木健吾、斉藤達夫、塩沢浩明、江原勝夫*

新コスモス電機、東京工業大学*

DEVELOPMENT OF METAL - OXIDE SEMICONDUCTOR ODOR SENSORS AND THEIR APPLICATIONS

T. Takada, K. Fukui, K. Suzuki, T. Saito, H. Siozawa and K. Ehara*

New Cosmos Electric Co.,Ltd.
2-5-4 Mitsuya-naka, Yodogawa-ku, Osaka 532-0036, Japan
*Tokyo Institute of Technology
2-12-1 Ookayama, Meguro-ku, Tokyo 152-855, Japan

Our approaches to development of metal-oxide semiconductor odor sensors are briefly reviewed. A series of odor sensors for various odors, S-contained odors and NH3 have been developed by examination of parameters that have an influence on sensing characteristics of semiconductor gas sensors, that is, by modification of SnO2 by CaO-addition for various odors, examination on sensing material and thickness of sensing layer (ZnO sensing layer with 10μm in thickness) for S-contained odors and study on Pd distribution in SnO2 for NH3 . Further, our challenges to odor identification using a SnO2-based sensor array and pattern recognition techniques are also presented. Odor selectivity against odorless gases was obtained by optimization of the grain size of SnO2 and addition of Pb-oxide to SnO2, and each sensing element of the array was endowed with a special odor-selectivity by formation of a metal-oxide catalyst layer on the SnO2-based sensing layer. Some odor identifications have been successfully performed by means of the odor identification sensor system.

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t1.

マイクロ化学分析システム (μTAS) の最新動向

庄子習一

早大理工

NEW TREND OF MICRO TOTAL ANALYSIS SYSTEMS (mTAS)

Shuichi SHOJI

Department of Electronics, Information and Communication Engineering, Waseda University
3-4-1, Ohkubo, Shinju-ku, Tokyo 169-8555, Japan

Microfabrication of total chemical/biochemical analysis systems, μTAS, have been developed. μTAS have many advantages on sample and reagent reduction, short analysis time, low cost etc. In this paper, four types of μTAS, Micro Electromechanical System (MEMS) type μTAS, including mechanical micro elements, Chip Capillary Electrophoresis (CE) type μTAS, Batch type μTAS, Gene chip used μTAS are reviewed.

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11.

ナノサイズ酸化スズ水熱処理ゾルから作製した薄膜のセンサ特性に及ぼす粒子径および膜厚の影響

白　南錫、酒井　剛、三浦　則雄、山添　f

九大院総理工

INFLUENCE OF GRAIN SIZE AND FILM THICKNESS ON GAS SENSING CHARACTERISTICS FOR TIN OXIDE THIN-FILMS PREPARED FROM HYDROTHERMALLY TREATED NANOCRYSTALLINE SOL SOLUTION

Nam seok BAIK, Go SAKAI, Norio MIURA, Noboru YAMAZOE

Department of Molecular and Material Sciences, Graduate School of Engineering Sciences, Kyushu University
Kasuga-shi, Fukuoka 816-8580, Japan

SnO2 nanocrystalline sol solutions were prepared hydrothermally. The grain size of SnO2 in the spin-coated thin-film finally obtained could be controlled by varying the SnO2 content of the sol solution and the sintering temperature. The hydrothermal treatment tended to surpress the thermal grain growth of SnO2, and the degree of suppression was more conspicious with decreasing SnO2 content of the sol solution. The influences of grain size and film thickness on the gas sensing characteristics of the obtained thin-films were investigated. The sensitivity to H2 increased with a decrease in grain size or film thickness. The thin-film device made from a 1.8 wt%-hydrothermally treated sol solution, with a grain size of 7.3 nm and a film thickness of 80 nm, showed the sensitivity about 10 times as high as that of a conventional SnO2 sensor, being able to detect 5 ppm H2 or 20 ppm CO satisfactorily.

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12.

酸化スズ系ガスセンサを用いたにおいの検知　−テルペン系および芳香族アルコール に対する検知特性−

玉置　純、八木康行、山本善史、松岡政夫

立命館大理工

DETECTION OF ODOROUS COMPOUNDS USING TIN OXIDE GAS SENSORS −SENSING PROPERT IES TO TERPENIC AND AROMATIC ALCOHOLS−

Jun TAMAKI, Yasuyuki YAGI, Yoshifumi YAMAMOTO and Masao MATSUOKA

Department of Chemistry, Faculty of Science and Engineering, Ritsumeikan University
Kusatsu-shi, Shiga 525-8577, Japan

Various SnO2 based sensors, pure and 18 kinds of SnO2 sensors modified with metal oxide, have been subjected to the detection of 6 terpenic alcohols (linalool, menthol, α-terpineol, citronellol, nerol, and geraniol) and 3 ar omatic alcohols (benzyl alcohol, phenethyl alcohol, and 3-phenyl-1-propanol) for the construction of odor sensing system. Among 18 modified sensors, the sensors that effectively enhanced the gas sensitivity were classified into two groups. One was the group of the Nd2O3-, SrO-, and MoO3-SnO2 sensors which showed high sensitivity to citronellol, geraniol, and aromatic alcohols, implying the use as a selective sensor to these gases. Another was the group of non-selective sensors. The In2O3-, BaO-, and ZnO-SnO2 sensors belonged this group and exhibited high sensitivity to all gases. The enhancement of gas sensitivity due to the modification was interpreted with respect to the increase in catalytic activity as well as the change of reaction route.

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13.

CeO2を添加したIn2O3センサのNOx検知特性

玉置　純、三浦哲三郎、石橋英樹、山本善史、松岡政夫

立命館大理工

NOx SENSING PROPERTIES OF CeO2-In2O3 SEMICONDUCTOR SENSORS

Jun TAMAKI, Tetsusaburo MIURA, Hideki ISHIBASHI, Yoshifumi YAMAMOTO, and Masao MATSUOKA

Department of Chemistry, Faculty of Science and Engineering, Ritsumeikan University
Kusatsu-shi, Shiga 525-8577, Japan

The NOx sensing properties of In2O3 semiconductor sensors modified with CeO2 have been investigated with respect to the exhaust monitoring. The addition of CeO2 enhanced the NO sensitivity when CeO2 was added with In2O3 at 5-35 wt%. The highest sensitivity of 10 (=Ra/Rg) to 50 ppm NO was obtained for the CeO2 (20 wt%)-In2O3 sensor at 300 ℃. On the other hand, t he sensor responded complicatedly to NO2. The electrical resistance decreased upon exposure to NO2, then steeply increased and returned to almost the same value as the initial resistance, suggesting the low sensitivity to NO2. Thus, the CeO2-In2O3 sensor was found to exhibit high NO sensitivity as well as high selectivity at 300℃. The electrical resist ance decreased upon exposure to NO in the presence of O2 (2-20%), while the resistance increased in the absence of O2. This suggests that NO behaves as a reducing gas in O2-containing atmosphere, i.e., reacts with adsorbed oxygen to be oxidized into NO2.

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14.

ジエトキシジメチルシランで表面化学改質したバリスタ型 SnO2 センサの H2 検出特性

兵頭健生、馬場泰臣、和田憲治*、清水康博、江頭　誠

長崎大工、佐世保高専*

H2 SENSING PROPERTIES OF VARISTOR-TYPE SnO2 SENSORS SUBJECTED TO SURFACE CHEMICAL MODIFICATION WITH DIETHOXYDIMETHYLSILANE

Takeo HYODO, Yasuomi BABA, Kenji WADA*, Yasuhiro SHIMIZU and Makoto EGASHIRA

Faculty of Engineering, Nagasaki University
1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
*Sasebo National College of Technology
1-1 Okishin-machi, Sasebo, Nagasaki 857-1193, Japan

Improvement of sensitivity to H2 of varistor-type SnO2 sensors was attempted by surface chemical modification with diethoxydimethylsilane (DEMS) which gives fine SiO2 particles on the surface of SnO2 powder. The breakdown voltage and H2 sensitivity increased with increasing the number of times of the DEMS treatment, and SiO2(3)/SnO2, the specimen of three times modification, showed the highest sensitivity among the SiO2/SnO2 specimens. A. c. impedance measurement was performed to investigate the variation in potential barrier height per grain boundary. The change in the potential barrier height induced by H2 was found to be the most important factor in determining the H2 sensing properties. The breakdown voltage of SnO2 loaded with 0.5 wt% Pd (Pd/SnO2) in air was almost equal to that of SiO2(3)/SnO2, but the H2 sensitivity of Pd/SnO2 was lower than that of SiO2(3) /SnO2. However, the H2 sensitivity of Pd/SnO2 was highly improved by the modification with DEMS.

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15.

アルコキシシランで表面化学改質したSnO2のH2ガス検出特性
和田憲治、江頭　誠*

佐世保高専、長崎大工*

HYDROGEN SENSING PROPERTIES OF TIN DIOXIDE SUBJECTED TO SURFACE CHEMICAL MODIFICATION WITH ALKOXYSILANES
Kenji WADA and Makoto EGASHIRA*

Department of Chemistry and Biotechnology, Sasebo National College of Technology
*Department of Materials Science and Engineering, Faculty of Engineering, Nagasaki University, Japan
1-14 Bunkyo-machi, Nagasaki-shi 852-8521, Japan

Hydrogen sensing properties of SnO2 were significantly enhanced by surface chemical modification with triethoxy(methyl)silane, diethoxydimethylsilane and ethoxytrimethylsilane. The enhancement was highly dependent on the number of ethoxy groups in the silanes, triethoxy(methyl)silane being most promising. Electrical resistance of SnO2 in air increased with the repeated surface modification, suggesting that the sensitivity enhancement was ascribable to the increased potential barrier height at the grain boundaries. However, introduction of a large amount of SiO2 decreased the gas sensitivity due to the decreased oxidation activity.

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16.

酸化スズ系COガスセンサの温湿度依存性

尾崎康隆，鈴木祥代，盛満正嗣*，松永守央*

フィガロ技研，九州工大工*

TEMPERATURE AND HUMIDITY DEPENDENCES OF PERFORMANCES OF SnO2-BASED CO GAS SENSORS

Yasutaka OZAKI, Sachiyo SUZUKI, Masatsugu MORIMITSU*, and Morio MATSUNAGA*

Figaro Engineering Inc.
1-5-11 Senbanishi, Mino, Osaka 562-0036, Japan
*Department of Applied Chemistry, Kyushu Institute of Technology
Tobata, Kitakyushu 804-8550, Japan

Improved performances of SnO2-based CO gas sensors modified by dipping treatments in noble metal chloride solutions are presented. The sensor elements impregnated in dilute aqueous solutions containing each of IrCl4, H2PtCl6, RuCl4, and RhCl3 become insensitive to variations in temperature and humidity, compared with the non-treated sensor element. The effects of temperature and humidity on the sensor resistance are more reduced by dipping treatment in the solution containing two kinds of the noble metal chlorides. The high long-term stability of the sensor resistance is also achieved with additional dipping treatments in sulfuric acid and thiourea solutions. In addition, the modified gas sensor shows the enhanced sensitivity and selectivity for CO gas detection.

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17.

湿度変動にともなう SnO2半導体の過渡挙動の解析

久世　恭、高橋祥夫

新コスモス電機株式会社

TRANSITIONAL BEHAVIOR OF TIN OXIDE SEMICONDUCTOR UNDER A STEP-LIKE HUMIDITY CHANGE

Takashi Kuse , Sachio Takahashi

New Cosmos Electric Co.,Ltd.
2-5-4 Mitsuya-Naka, Yodogawa-ku, Osaka 532-0036, Japan

The effects of water vapor on SnO2, In2O3 and ZnO thick film sensors were investigated by measurement of resistance. Especially, the long span effects of water vapor were investigated on the basis of chemical kinetics in detail. Time-dependent behavior in the resistance under a step-like change in humidity consisted of an initial large change followed by an exponential change in a long span, which was observed over a wide range of sensor temperature in SnO2. Such transitional behavior was also observed in the In2O3 and ZnO based sensors. From a chemical kinetics based analysis of the exponential change in SnO2, two different elementary reaction processes were assigned in each sensor temperature range above or below 330℃, respectively. It was found that the processes of adsorption and desorption of water vapor on semiconductor sensors were the time-consuming ones with an inherent activation energy in each sensor temperature range. Thus, some important findings to evaluate the effects of water vapor on the semiconductor sensors were obtained in the present study.

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18.

常温動作型酸化インジウム系熱線型半導体式ＣＯセンサ
佐藤武司、三橋弘和、高橋祥夫

新コスモス電機株式会社

ROOM TEMPERATURE OPERATED HOT WIRE SEMICONDUCTOR TYPE CO SELECTIVE GAS SENSOR BASED ON INDIUM OXIDE

Takeshi SATO, Hirokazu MITSUHASHI, Sachio TAKAHASHI

New Cosmos Electric Co.,Ltd.
2-5-4, Mitsuya-naka, Yodogawa-ku, Osaka 532-0036, Japan

Hot wire semiconductor type CO selective gas sensor was developed by using sintered indium oxide. This sensor had high sensitivity and selectivity to CO at sensor temperature of 20℃. The response to CO was quicker than conventional CO sensor using tin oxide. The sensitivity to CO was not nearly affected by variation of ambient temperature and humidity. The average power consumption was about 0.05 mW, as a result this sensor operates on two AA-size alkaline batteries for two years. Furthermore, long term stability had been confirmed for half a year.

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19.

ガス濃縮法を組み込んだセンサシステムの検討

緒方　靖士、酒井　剛、三浦則雄、山添　f

九大院総理工

GAS-SENSING SYSTEM USING GAS-ENRICHING SCHEME

Yasushi Ogata, Go Sakai, Norio Miura, Noboru Yamazoe

Department of Molecular and Material Sciences, Graduate School of Engineering Sciences, Kyushu University Kasuga-shi, Fukuoka 816-8580, Japan

A gas-sensing system consisting of a gas-sensor and a gas-enriching part was investigated. Gas-enrichment was carried out by enforcing temperature swing (heating-and-cooling cycle) on a gas-adsorbent. Among the various materials tested, Li(H)-ZSM-5 was found to be the most useful adsorbent for enriching NH3 even in humid atmospheres. NH3 could be enriched successfully with the temperature swing between 300。C and 500。C. The NH3 enrichment ratio was determined primarily by the ratio of adsorption time to desorption time. The gas-enriching part could be scaled-down by coupling electric-coil heating and metallic radiator cooling, allowing a temperature cycle within ca. 2 min. The resulting system could detect NH3 in the concentration range above 0.1 ppm in air without interference by changes in relative humidity (10-90%).

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20.

CH4−CO複合型センサ

町田博宣、小寺志珠、中原　毅、松浦吉展

フィガロ技研（株）

COMPLEX SENSOR FOR DETECTION OF CH4 AND CO

Hironobu MACHIDA，Shizu KOTERA，Takeshi NAKAHARA，and Yoshinobu MATUURA

Figaro Engineering Inc.
1-5-11，Senbanishi，Mino，Osaka 562，Japan

Demands for detecting leakage of combustible gases such as CH4 and toxic gases such as CO caused by incomplete combustion have rapidly arisen in recent years.　By using an alternate temperature changing technique on a single sensor chip, we have developed SnO2 gas sensor which can detect hydrocarbons in high temperature period and CO in low temperature period． Two sensing materials, one was sensitive to CH4 at high temperature and the other was sensitive to CO at low temperature, were formed on a single sensor chip.　The sensors were periodically kept at high and low temperatures with a constant interval by changing the applied voltage to a heater. In this study, we investigated the correlation between sensor characteristics such as long term stability and sensor structure or temperature distribution of sensor surface. As a result, the long term stability of CH4-CO sensor, especially for detecting CO, was improved.

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21.

COセンサの相対湿度依存性とその補償

高松和子、新西一哉、宇高利浩、中原毅、松浦吉展

フィガロ技研株式会社

RELATIVE HUMIDITY DEPENDENCY OF SnO2 CO SENSOR AND ITS COMPENSATION

Kazuko TAKAMATSU,　Kazuya SINNISHI,　Toshihiro UDAKA, Takeshi NAKAHARA,　Yoshinobu MATSUURA

Figaro Engineering Inc.
Minoo-shi, Osaka 562-8505, Japan

The relative humidity dependency of a SnO2 CO sensor, which is heated at the higher temperature and the lower temperature alternately, was successfully compensated. CO was detected at the end of the lower temperature period and the sensor output at the detection point was compensated with the sensor output at the early stage of the higher temperature period. These two outputs had a correlation with each other good for the purpose of compensation. In the compensation program developed, a compensation factor was retrieved from a look up table with an index calculated based upon the compensation output and was multiplied by a CO concentration value into a compensated value that showed by far less humidity dependency.

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22.

乾電池電源型半導体ガスセンサの開発

翁長　一夫、島袋　宗春、松本　晋一

エフアイエス株式会社

DEVEROPMENT OF SEMICONDUCTOR GAS SENSOR FOR BATTERY OPERATION

Kazuo Onaga, Muneharu Shimabukuro and Sinichi Matsumoto

FiS Inc.
3-36-3 Kitazono, Itami-shi, Hyogo 664-0891, Japan

A battery operated gas sensor was developed with tin oxide semiconductor. A miniature bead type element was employed for minimum heat mass. To attain reduced power consumption, an alternating ON-OFF cycle of the heater voltage was applied with a short ON period (e.g. 0.5 - 1.0 sec) and a long OFF period (e.g. 200 seconds). Under these conditions, water in ambient air reacted with the sensor surface during the OFF period. As the results, the resistance in air became lower and gas sensitivity decreased. This problem was solved by applying a pulse voltage as circuit voltage. This battery operated gas sensor can function for up to 2 years.

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23.

乾電池電源型半導体ガスセンサの機器への応用

松本　隆、草野　修二、田中　克之

エフアイエス株式会社

APPLICATIONS OF BATTERY OPERATED SEMICONDUCTOR GAS SENSOR

Takashi Matsumoto, Shuji Kusano and Katsuyuki Tanaka

FiS Inc. Development Group
3-36-3 Kitazono, Itami-shi, Hyogo 664-0891, Japan

We have studied the technology of using a mini-bead type semiconductor gas sensor for battery operated applications. The sensing element is heated to approx. 420℃ for 0.8 seconds in 200 seconds of heating cycle. This condition provides a 1 mW of average power consumption and achieves the continuous operation for more than two years using four AA type batteries. We have evaluated the performance of this technology from various aspects, and found that this method provides sufficient gas detection performances in various commercial applications such as battery operated CO, LP-Gas detection or Indoor Air Quality monitoring devices.

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24.

IDENTIFICATION OF 7 KINDS OF ALCOHOL VAPORS AT ARBITRARY CONCENTRATION USING A SEMICONDUCTOR ODOR SENSOR SYSTEM

K. Cai, K. Suzuki, T. Maekawa, T. Takada and T. Kobayashi*

New Cosmos Electric Co. Ltd.
2-5-4 Mitsuya-naka, Yodogawa-ku, Osaka 532-0036, Japan
*Osaka national research institute
Midorigaoka 1-8-31, Ikeda 563-8577, Japan

An odor sensor system has been constructed with a semiconductor sensor array based on SnO2 thick films with 8 sensing elements. The odor selectivity of the sensing elements were much promoted by coating metal oxides catalyst layers on the surface of the elements. The identification of odors at arbitrary concentrations was done with 7 kinds of alcohol gases as odors, within a range of 1-100 ppm, using the sensor system. In the recognition process, a neural network algorithm was applied and all of the odors were correctly discriminated.

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25.

ガスセンサの応答遅れを考慮した自動車用換気装置

中川英元、岡崎慎司、朝倉祝治、秋本英雄*、久保純**、重盛徹志***、高橋 祥夫***

横浜国大工、 ＡＣＥ*、 クボシステムズ**、 新コスモス電機***

AＮ AUTOMATIC VENTILATION SYSTEM WITH AN AIR RESERVOIR TO COMPENSATE SENSOR RESPONSE DELAY

Hidemoto NAKAGAWA, Shinji OKAZAKI, Shukuji ASAKURA, Hideo AKIMOTO*, Jun KUBO**, Tesshi SHIGEMORI***, Sachio TAKAHASHI***

Dept. of Mat. Sci. and Chem. Eng, Yokohama National University
Yokoham 240-8501, Japan
*Advanced Circuit Engineering Co.
Kawasaki 213-0012, Japan
**Kubo Systems Inc.
Shinjuku, Tokyo 161-0034, Japan
***New Cosmos Electric Co. Ltd.
Osaka 532-0036, Japan

A new design of an automatic ventilation system, which inhibits the transient intake of polluted air due to slow response of a gas sensor, is presented. The system keeps outside air in a reservoir before it introduces the air into the cabin to judge the air quality by the gas sensors. It has been found that the system effectively avoids the intake of the CO and hydrocarbonic(HC) gases. Driving data on public roads indicate that the pollution level on roads varies widely according to the traffic amount, speed, congestion, wind and other conditions. Even with the same amount of traffics, the pollution level is considerably lower when traffic is smoothly running. Also the pollution level of exhaust gas varies widely from car to car. It was observed that a small number of poorly maintained cars tend to make large contribution on air pollution.

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26.

就寝中におけるガス・ニオイセンサ特性

大薮 多可志、南戸 秀仁*、笠原 浩**、松浦 吉展***

金沢経済大学、金沢工業大学*、新コスモス電機**、フィガロ技研***

ODOR SENSING CHARACTERISTICS IN RESIDENTIAL BEDROOMS

Takashi OYBU, Hidehito NANTO, Hiroshi KASAHARA, and Yoshinobu MATSUURA

Kanazawa University of Economics
Kanazawa 920-8620, Japan
*Kanazawa Institute of Technology
Kanazawa 924-0838, Japan
**New Cosmos Electric Co., LTD.
Osaka 532-0036, Japan
***Figaro Engineering Inc.
Osaka 562-0036, Japan

Odor sensors are used in various fields such as food, perfume and indoor environments. Many kinds of odors are generated even in human life. For instance, an odor sensor reacts while one is sleeping. The interrelation between sensor output and human vital signs is examined. Middle age and aged couples are selected as the subjects. The low pass filtering method and the three-point method of numerical differentiation are used to analyze the sensor outputs. As for the results, sensor characteristics have high frequency components at all times in the bedroom of the aged couple, while the odor sensor outputs in the bedroom of middle age couple have characteristics that resemble stairs. The average interval of the steps is about 60 to 100 minutes.

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27.

Pt/WO3膜のライン型ファイバ水素センサへの適用(II)

関本慎二郎、岡崎慎司、中川英元、朝倉祝治、福田健三、重盛徹志*、高橋祥夫*

横浜国大工、新コスモス電機*

THE APPLICATION OF Pt/WO3 THIN FILM TO A FIBER-OPTIC EVANESCENT-WAVE HYDROGEN GAS SENSOR (II)

Shinjiro SEKIMOTO, Shinji OKAZAKI, Hidemoto NAKAGAWA, Shukuji ASAKURA, Kenzoh FUKUDA, Tessi SIGEMORI* and Sachio TAKAHASI*

Yokohama National University
Hodogaya-ku, Yokohama 240, Japan
*New Cosmos ELectric Co.

An optical-fiber evanescent-wave hydrogen gas sensor was developed and characterized. Pt/WO3 was coated on the surface of the core by the sol-gel process. It has been found that the condition of the film and length of the sensor device easily influence the characteristics of the sensor. Experimental results were discussed on the basis of the plan wave model. The tendencies of the change of absorbance and the relation of the sensitivity with film thickness were examined. 　

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28.

複合光導波路におけるTE-TMモードの干渉を用いた高感度センサの開発

祁　志美、伊藤公紀、村林眞行、柳　裕之*

横浜国立大学環境研、トクヤマ*

HIGHLY SENSITIVE SENSOR BASED ON INTERFERENCE BETWEEN TE AND TM MODES AT COMPOSITE OPTICAL WAVEGUIDES

Zhimei QI, Kiminori ITOH, Masayuki MURABAYASHI and Hiroyuki YANAGI*

Insititute of Environmental Science and Technology, Yokohama National University
Yokohama 240-0069, Japan
*TOKUYAMA Co., Ltd.
Fujisawa, Kanagawa 252-0816, Japan

Composite optical waveguides were applied to an interferometer. TE and TM modes were introduced into a K+/TiO2 waveguide in such a manner that only TE mode can be transferred into the thin film TiO2 waveguide. Thus, the two modes yield a difference in their effective refractive indices, which depends on the refractive index of the clad (nc). It was obserced theoretically as well as experimentally that the guided light intensity oscillates when nc was changed. Changes in nc as small as 10-6 can be detected with this system. 　

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29.

水晶振動子式ガスセンサを用いた悪臭ガスの認識と検知

南戸秀仁、堂上長則、向井達哉、横井康平、中田尚将、草野英二、小川俊夫*、金原　繁

金沢工大　高材センター・物質応用*、金沢経済大学**

IDENTIFICATION OF HARMFUL GASES USING POLYMER0FILM-COATED QUARTZ RESONATOR GAS SENSOR

Hidehito NANTO, Naganori DOUGAMI, Tatsuya MUKAI, Yasuhira YOKOI, Naomasa NAKADA, Eiji KUSANO, Toshio OGAWA*, Akira KINBARA and Takasi OYABU**
A.M.S.R&D Center and *Depart. of Mater. Sci. Eng., Kanazawa Inst. of Tech., **Kanazawa University of Economics

The transient responses for harmful gases sucha s toluene, xylene, ammonia and acetaldehyde were observed using three kinds of quartz resonator gas sensors coated, respectively, with propylene-butylene-, acrylic-resin- and polycarbonate-thin-film. The each sensor with propylene-butylene-thin-film, acrylic-resin-thin-film and polycarbonate -thin-film as molecular identification film exhibited excellent selectivity for toluene, ammonia and acetaldehyde, respectively, which was expected in the view point of solubility parameter. It was clear that the principal component analysis for individual gases tend to cluster in discrete sections of space with well defined boundaries. 　

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30.

塩化リチウムー多孔質ポリマー複合膜を用いた露点計

巻幡晴也、松口正信、酒井義郎、小原幸子*、小倉　勉*、黒岩孝朗*

愛媛大工・山武*

A DEW POINT SENSOR USING LITHIUM CHLORIDE DOPED POROUS FILM

Haruya MAKIHATA, Masanobu MATSUGUCHI, Yoshiro SAKAI, Sachiko OBARA, Tsutomu OGURA, and Takaaki KUROIWA

Department of Applied Chemistry, Faculty of Engineering, Ehime University
Matsuyama, Ehime 790-8577, Japan
Yamatake Company Limited
Fujisawa 251-0015, Japan

A novel dew point sensor was prepared by using porous films consisting of poly(vinyl alcohol) and poly(methyl methacrylate) or poly(vinyl alcohol) and poly(styrene). LiCl was kept in the pore to avoid the effusion due to a dew condensation. The optimum conditions for preparing the porous film were determined from the impedance-humidity charactersitic. The dew point experimentally obtained by using the optimized porous film agreed fairly well with the true value. It was proved that a porous film consisting of PVA-PMMA was applicable for a reliable dew point sensor.

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31.

容量型湿度センサの高温平成明朝・高湿における出力ドリフトの原因

広田悦朗、松口正信、黒岩孝朗*平成明朝、小原幸子*、小倉　勉*、酒井義郎

愛媛大工・山武*

LONG-TERM STABILITY OF A CAPACITIVE-TYPE HUMIDITY SENSOR IN A HOT AND WET ATMOSPHERE

Etsuro HIROTA, Masanobu MATSUGUCHI, Takaaki KUROIWA, Sachiko OBARA, Tsutomu OGURA, and Yoshiro SAKAI

Department of Applied Chemistry, Faculty of Engineering, Ehime University
Matsuyama, Ehime 790-8577, Japan
Yamatake Company Limited
Fujisawa 251-0015, Japan

The drift phenomenon of a capacitive-type humidity sensor in a hot and wet atmosphere was investigated using various sensing polymers. The amount of sorbed water on the sensing polymer increased with an increase in a storage time in the atmosphere. While this phenomenon caused the drift of the sensor output, the magnitude of the drift did not simply depend on an increase in the amount of sorbed water. IR analysis showed that the state of the sorbed water also affected the magnitude of the drift.

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32.

塩基型ポリアニリン/ポリビニルアルコール複合膜電極によるCO2センシング

椎木　弘，福田篤志，中山雅晴，小倉興太郎

山口大工

CO2 SENSING USING THE POLYMERS COMPOSITE ELECTRODE CONSISTING OF BASE-TYPE POLYANILINE / POLY(VINYL ALCOHOL)

Hiroshi SHIIGI, Atsushi FUKUDA, Masaharu NAKAYAMA and Kotaro OGURA

Department of Applied Chemistry, Yamaguchi University
Tokiwadai, Ube 755-8611, Japan

Heat-treatment of PANA at elevated temperature (280℃, 8h) led to the elimination of carboxyl group, and to the formation of base-type polyaniline (PAn). The composite film consisting of the base-type PAn and PVA was cast on a Pt comb-shaped microelectrode. The composite electrode responded to CO2 gas at room temperature and the electrical conductivity were linearly related with the concentration of CO2, extending from 5.95x10-5 to 6.04x10-3 Scm-1 upon the concentration change of CO2 from 50 ppm to 104 ppm. The increase in electrical conductivity of the composite film in proportion to the CO2 concentration is attributed to the transformation of the insulating base-type PAn to the conducting salt-type which are caused by the incorporation of carbonate ions formed by the hydrolysis of CO2 into the former type PAn.

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33.

酸化ルテニウム電極を用いたアンペロメトリックセンサによるHClガ ス検出

今屋浩志、打越祥一、石地　徹

理研計器

AMPEROMETRIC SENSOR FOR DETECTION OF HCl BY USING RUTHENIUM OXIDE ELECTRODE

Hiroshi IMAYA, Shoichi UCHIKOSHI and Toru ISHIJI

Riken Keiki Co., Ltd.
2-7-6 Azusawa Itabashi-ku, Tokyo 174-8744, Japan

An amperometric sensor based on a pH sensitive cathodic reaction of Ruthenium oxide for detection of HCl was studied. This sensor could be detected low concentration of HCl gas, which is useful for HCl monitoring. To improve a selectivity of HCl against CO2, the electrolytic solution composition of the sensor was investigated. It was found that CO2 influence was depressed by addition of ethylene glycol to electrolytic solution.

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34.

pO2、pCO2、pH測定用微小集積化モジュールの試作

平川大志、鈴木博章、佐々木聰*、軽部征夫*

筑波大物質工・東大先端研*

FABRICATION OF AN INTEGRATED SENSING MODULE FOR pO2, pCO2 AND pH

Taishi HIRAKAWA, Hiroaki SUZUKI, Satoshi SASAKI*, and Isao KARUBE*

Institute of Materials Science, University of Tsukuba
Koganei, Tokyo 184, Japan
1-1-1 Tennodai,Tsukuba, Ibaraki 305-8573
*RCAST, The Univercity of Tokyo
4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan

An integrated module for sensing pO2, pCO2 and pH was fabricated. A novel thin-film Ag/AgCl structure was used for each electrode, where entire surface of a silver pattern was covered with a polyimide layer and the AgCl layer was grown from slits at the periphery of the polyimide layer. A miniature Clark-type oxygen electrode was used for pO2 sensing. An anodically grown iridium oxide film (AIROF) was used as the sensing element of the pH electrode and the Severinghaus-type pCO2 electrode. Clear responses were observed and expected dependency of output current or potential on corresponding analyte was confirmed with each of these electrodes. As with the pH electrode the potential of the indicator electrode was compared using the integrated liquid-junction Ag/AgCl reference electrode and a macroscopic Ag/AgCl reference electrode. No substantial difference was observed.

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35.

微小液絡型銀／塩化銀参照電極とそのワンチップポテンショメトリックセンサへ の応用

城石久徳、鈴木博章、佐々木聰*、軽部征夫*

筑波大物質工、東大先端研*

MICTOFABRICATED LIQUID-JUNCTION Ag/AgCl REFERENCE ELECTRODE AND ITS APPLICATION TO A ONE-CHIP POTENTIOMETRIC SENSOR

Hisanori SHIROISHI, Hiroaki SUZUKI, Satoshi SASAKI*, and Isao KARUBE*

Institute of Materials Science, University of Tsukuba
1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan
*RCAST, The University of Tokyo
4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan

A liquid-junction Ag/AgCl reference electorode was microfabricated. The Ag/AgCl element was formed by covering the surface of a silver pattern with a polyimide layer and growing AgCl from a slit at the center. An electorolyte layer was formed by screen-printing a paste containing fine KCl powder. The liquid junction was formed by a photocrosslinkable ENT resin. The electrolyte layer and the liquid junction were covered with a silicone rubber passivation layer. The novel thin-film Ag/AgCl element could maintain its expected potential for more than 30 h. The completed miniature liquid-junction reference electrode with a 50-μm-wide juntion maintained a stable potential level for more than 100 h with the aid of a PVP matrix in the electrolyte layer. Fluctuation of the potential was less than 0.1 mV at each moment. No substantial dependency on external KCl concentration and pH was confirmed. The miniature reference electrode was applied to a one-chip pH sensor, which showed distinct responses to pH step changes.

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36.

耐熱性酵素グルタミンシンテターゼを用いたISFET型グルタミン酸センサの構築と特性
大竹秀紀、石丸雄大、飯田武揚

埼玉大工

CHARACTERISTICS OF ISFET-TYPE GLUTAMATE SENSOR USING THERMOPHILIC GLUTAMINE SYNTHETASE
Hideki OHTAKE, Yoshihiro ISHIMARU, Takeaki IIDA

Department of Function Materials Science, Faculty of Engineering, Saitama University
255 Shimo-okubo, Urawa-shi, Saitama-ken 338-8570, Japan

An ion sensitive field effect transistor(ISFET) type glutamate sensor was studied using an immobilized thermophilic enzyme glutamine synthetase from a moderate thermophilic bacterium. The ISFET glutamate sensor, on which the glutamine synthetase and albumin were immobilized by glutaraldehyde, was able to determine the glutamate concentration in the range from 0.1mM to 10mM. The response time of glutamate sensor was about 3 min. And no response was obtained to any other substrates except D-glutamate. Therefore, the glutamate sensor was found to have high selectivity for L-glutamate. The glutamate sensor up to 55℃, so the glutamate sensor was found to be use at high temperatures and to be durable for pasteurization.

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37.

耐熱性酵素を用いたISFET型バイオセンサによるβ-グルコシド配糖体の検知
青木　一仁、石丸　雄大、飯田　武揚

埼玉大学 工学部

DETECTION OF β-GLUCOSIDIC GLYCOSIDES BASED ON AN ISFET-TYPE BIOSENSOR USING THERMOPHILIC ENZYMES
Kazuhito AOKI, Yoshihiro ISHIMARU, and Takeaki IIDA

Department of Functional Materials Science , Faculty of Engineering, Saitama University
255 Shimo-okubo, Urawa-shi, Saitama-ken 338-8570, Japan

An ion sensitive field effect transistor (ISFET) β-glucosidic glycoside sensor is described. In order to develop useful biosensor, the thermophilic glucokinase (GK) from Bacillus stearothermophilus and thermostable β- glucosidase from Caldocellum Saccarolyticum which was more extracted than previous study, were immobilized on the ISFET surface. As the results, the sensor was able to determine the concentrations of β-D-glucosidic glycoside such as D-salicin, esculin or cellobiose, on a discrete sensing system. Moreover, the ISFET sensor was able to determine various β-glucosidic glycosides under the conditions from room temperature to 60℃. It was found that the glucosidic glycoside sensor was suitable for detection variousβ-glucosides.

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38.

電流電位計測法によるコリンエステラーゼを用いるバイオセンサ
Olga V. Fedosseeva, 石丸 雄大、飯田 武揚

埼玉大工

CHOLINESTERASE-BASED BIOSENSOR USING VOLTAMMPEROMETRIC METHOD
Olga V. FEDOSSEEVA, Yoshihiro ISHIMARU, and Takeaki IIDA

Department of Functional Materials Science, Faculty of Engineering, Saitama University
255 Shimo-okubo, Urawa-shi, Saitama-ken 338-8570, Japan

This work confirms the result that by electropolymerization of an acetylcholinesterase-pyrrole mixture the poolypyrrole(PPy)-modified platinum electrode was made for voltammetric analysis. THe sensor behaviour was evaluated electrochemically with a hanging mercury-drop electrode. The sensor was operated using acetylthiocholine as an enzyme substrate.

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39.

分子インプリント固定電極の交流応答特性を利用した化学センシングの可能性

吉見靖男、飯山千秋、大平亮

芝浦工業大学

A CHEMICAL SENSOR USING ALTERNATING CURRENT AMPEROMETRY WITH MOLECULARLY IMPRINTED ELECTRODE

Yasuo YOSHIMI, Chiaki IIYAMA and Ryo OHDAIRA

Department of Industrial Chemistry, Shibaura Institute of Technology
Minato-ku, Tokyo 108-8548, Japan

The authors studied the effect of guest molecule on alternating current polarography by indium-tin oxide (ITO) electrode on which molecularly imprinted polymer was grafted. Methacrylic acid and ethylene glycol dimethacrylate was copolymerized in the presence of theophylline as a guest and of methacryloxypropyltrimethoxysilane-treated ITO. The copolymer was grafted on the ITO. A sinuated potential was applied on the copolymer grafted ITO as electrode in the presence / absence of theophylline. The presence of theophylline enhanced negative current. While the presence of caffeine hardly changed the anodic current. Theses results suggested that an electrode grafted molecularly imprinted polymer is functional as selective chemical sensor.

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40.

フロー型集積化酵素センサにおける化学的クロストークと酵素固定化方法との関 係

鈴木正康、赤熊浩行

九工大情報工

EFFECTS OF ENZYME IMMOBILIZATION METHODS ON THE CHEMICAL CROSS TALK IN FLOW-TYPE INTEGRATED ENZYME SENSORS

Masayasu SUZUKI and Hiroyuki AKAKUMA

Department of Biochemical Engineering and Science, Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology
Iizuka-shi, Fukuoka 820-8502, Japan

In flow-type integrated enzyme sensors, hydrogen peroxide produced at an upstream electrode is transported to downstream electrodes, and causes non-specific responses which are called as "chemical cross talk (CCT)".In this study, the relationship between CCT and enzyme immobilization methods, namely an electrochemical pyrrole polymerization, a gelatin-glutaraldehyde crosslinking, and a photocrosslinkable prepolymer (PVA-SbQ) method, was investigated. The flow rate dependen-cy and the substrate concentration dependency of CCT were dependent on the enzyme immobilization methods.Therefore, the effects of the membrane permeability and enzyme density of bioselective layers on upstream and downstream electrodes, on CCT were investigated by using a gelatin-glutar-aldehyde crosslinking method as an enzyme immobilization method. The CCTs were correspond to the membrane permeability and enzyme density of a bioselective layer on an upstream electrode. Based on these results, an elimination method for CCT was proposed.

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41.

微少量ラジアルフローセルのバイオセンサ、キャピラリ 電気泳動検出器への応用

丹羽　修、劉　志明、栗田　僚二*、森田　雅夫**、鳥光　慶一**

NTT生活環境研究所、ＮＴＴ-AT*、ＮＴＴ物性基礎研究所**

ULTRA-SMALL VOLUME RADIAL FLOW CELLS APPLIED AS DETECTORS FOR CAPILLARY ELECTROPHORESIS AND AS BIOSENSORS

Osamu NIWA, Zhiming LIU, Ryoji KURITA*, Masao MORITA** and Keiichi TORIMITSU**

NTT Lifestyle and Environmental Technology Laboratories
*NTT-AT
**NTT Basic Research Laboratories
3-1 Morinosato, Wakamiya, Atsugi, Kanagawa, 243-0198, Japan

We fabricated small volume radial flow cells by combining film electrodes with fused silica capillaries and used them as detectors for capillary electrophoresis (CEEC) and as on-line biosensors. For the CEEC detectors, we aligned an interdigitated array (IDA) electrode below the capillary outlet using a micropositioner. Since a catecholamine signal can be enhanced by redox cycling at an IDA after electrophoretic separation, the detection limit was greatly improved. We made the on-line sensors by fabricating a capillary, electrode guides and flow channels in a glass plate. Since we could reduce the active volume to a sub-nl level, the response of the sensor was very quick even with a flow rate of 20 nl/min. We modified the film electrode with glutamate oxidase and Os-polyvinylpyrridine containing horseradish peroxidase (Os-gel-HRP) and used it to measure the glutamate release from a cultured rat cortex. We observed the transient glutamate release with a short response time by electrically stimulating the nerve cells with microelectrodes.

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42.

ポリウレタンを酵素固定材料に用いたバイオセンサの開発
安澤幹人、橋本　優、宮本直子、中村俊文、椚　章、仲矢忠雄*

徳島大工・阪市大工*

PROPERTIES OF GLUCOSE SENSORS BASED ON THE COVALENT　IMMOBILIZATION OF GLUCOSE OXIDASE IN POLYURETHANE FILMS
Mikito YASUZAWA, Masaru HASHIMOTO, Naoko MIYAMOTO, Toshifumi NAKAMURA, Akira KUNUGI and Tadao NAKAYA*

Department of Chemical Science and Technology, Faculty of Engineering, The University of Tokushima
2-1 Minamijosanjima, Tokushima 770-8506, Japan
*Department of Bioapplied Chemistry, Faculty of Engineering, Osaka City University
3-3-138 Sugimoto, Sumiyoshi, Osaka 558-8585, Japan

New glucose sensors based on the covalent immobilization of glucose oxidase in hemocompatible polyurethane film was prepared and the glucose sensor properties were investigated. Segmented polyurethane containing both phosphatidylcholine moieties and covalently reactive functional groups were synthesized and applied as enzyme immobilizing reagents. Two kinds of covalently reactive functional groups, N-Hydroxysuccinimidyl groups and amino groups were employed. The prepared electrodes showed linear relationship between the glucose concentration and the response current up to 7.0 mM. The electrodes prepared from both segmented polyurethanes were found to show stable response current for more than 50 days after an initial loss of signal over the first few days.

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43.

チロシナーゼを用いた酸素およびシアンセンサー

立間　徹、小川高史、佐藤亮太、小山　昇

東京農工大工

TYROSINASE ELECTRODE AS A SENSOR FOR OXYGEN AND CYANIDE

Tetsu TATSUMA, Takashi OGAWA, Ryota SATO, and Noboru OYAMA

Department of Applied Chemistry, Faculty of Technology, Tokyo University of Agriculture and Technology
Koganei, Tokyo 184-8588, Japan

An ion complex containing tyrosinase is formed on the electrode surface from a sulfonated polyaniline, poly(2-methoxyaniline-5-sulfonic acid) (PMAS), and a polycation, poly(L-lysine) (PLL). The electrode responds amperometrically to dissolved oxygen at pH 4.5 (at +0.2 V vs. Ag/AgCl or less positive potentials) and 7.4 (at +0.0 V vs. Ag/AgCl or less positive potentials) . The response was inhibited by the presence of NaCN. The NaCN concentration can be determined on the basis of the inhibition.

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44.

抗体累積膜の調製と特性評価

斉木　秀和、星　友典、安斉　順一

東北大薬

PREPARATION AND CHARACTERIZATION OF ANTIBODY MULTILAYERS

Hidekazu Saiki, Tomonori Hoshi, and Jun-ichi Anzai

Faculty of Pharmaceutical Sciences, Tohoku University
Aramaki, Aoba-ku, Sendai 980-8578, Japan

In order to improve the performance of immunosensors, antibody multilayers were prepared on a quartz slide. Texas Red avidin (T-avi) and biotinylated anti FITC antibody (B-anti-FITC) were deposited alternately on a hydrophobic surface of the quartz slide. The formation of the multilayer film was confirmed by absorbance change at 595 nm originating from Texas Red moiety in T-avi. It was found absorbance at 595 nm increased in proportion to the number of antibody layers. For the estimation of binding activities, the slide was immersed in an antigen (FITC-glycine) solution. The enhanced absorbance originating from FITC was observed at 495 nm. These results suggest that antibodies could form multilayer structure without loss of the binding activities.

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45.

エバネセント波蛍光測定によるビオチンのバイオアフィニティセンシング

横田佳奈、篠原寛明、宍戸昌彦

岡山大工

BIOAFFINITY SENSING FOR BIOTIN BY USING EVANESCENT WAVE-INDUCED FLUORESCENCE MEASUREMENT

Kana YOKOTA, Hiroaki SINOHARA, and Masahiko SISIDO

Bioscience and Biotechnology, Faculty of Engineering, Okayama University
3-1-1 Tsushima-naka, Okayama 700-8530, Japan

Bioaffinity sensing systems for biotin which are not only simple and sensitive but also reusable, were proposed. The systems were made by combining affnity binding reaction of biotin or biotin analogue-modified protein to avidin with fluorescence measurement using evanescent wave-excitation. Different bining affinities of three kinds of biotin analogue-modified proteins to avidin made different results for detection range of biotin. And repeated measurements were performed by application of bioaffinity binding and dissociation.

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46.

アンペロメトリック尿素センサの作製と評価（IV）

武居　修、外山　滋、宇佐美論*、掘越弘毅*、碇山義人

国立リハビリ研、東洋大工*

FABRICATION AND EVALUATION OF AMPEROMETRIC UREA SENSOR (IV)

Osamu Takei, Usami Ron*, Koki Horikosi*, Shigeru TOYAMA and Yoshihito IKARIYAMA

Research Institute, National Rehabilitation Center for the Disabled
4-1 Namiki, Tokorozawa 359-8555, Japan
*Faculty of Engineering, Toyo University
2100 Nakanodai, Kujirai, Kawagoe 350-8585, Japan

We have been developing a novel urea sensor based on microfabricated electrode where urease, glutamate dehydrogenase and glutamate oxidase are coimmobilized. The porous micro platinized electrode has a high sensitivity because it has about 1,000 times larger area than flat platinum electrode. However, the sensor sensitivity was not necessarily high at this stage of study. Therefore, we scrutinized the ratio of three enzymes which are to be immobilized on the electrode. The evaluation of immobilization rate was carried out by measuring comsumption of substrate and the production of enzymeatic reaction at on optimum bienzyme reaction spectrophotometrically. Trienzyme sensor was thus manufactured by comparing the spectroscopic data. Furthermore, pulse method was applied to increase sensor response.

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47.

金薄膜表面高分子層の最適設計と SPRセンサの高感度化(II)

東海林崇、滝田亮一*、外山滋、碇山義人

国立リハビリ研、工学院大工*

DESIGN OF POLYMER MATRIX FOR THE SENSITIZATION OF SPR-BASED IMMUNOSENSOR

Atsumu SHOJI, Ryoichi TAKITA*, Shigeru TOYAMA and Yoshihito IKARIYAMA

Research Institute, National Rehabilitation Center for the Disabled
4-1 Namiki, Tokorozawa 359-0042, Japan

Realtime and nonlabelled sensing based on antigen-antibody reaction has been investigated by a surface plasmon resonance(SPR)-based optical biosensor. The sensor detects effectively the change in the refractive index of the metal film surface upon injection of antigen / antibody due to the bulkness of large molecular polymer. Here, the characteristics of the sensor on gold surface attached high polymer CMC are reported; immobilization of antigen / antibody on gold surface was performed by covalent immobilization to carboxy methyl cellulose (CMC). Rapid detection of antigen / antibody reaction has also been examined.

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48.

Helicobacter pylori菌及びその破砕物のSPRによる検出

西村 知晃、一二三 恵美、宇田 泰三

広島県立大生物資源

DETECTION OF Helicobacter pylori USING SURFACE PLASMON RESONANCE

Tomoaki NISHIMURA, Emi HIFUMI and Taizo UDA

School of Biosciences, Hiroshima Prefectural University
Shoubara-shi, Hiroshima 727-0023, Japan

Helicobacter pylori (H.pyroli) causes chronic gastritis and gastric ulcer. It is important to detect the H.pyroli to administrate of anti-biotics for patients. We have established a unique monoclonal antibody which has a specificity against H.pyroli urease. Moreover it hugely suppresses the enzymatic activity of the urease. In this study, H.pyroli and its sonicated sample were detected by using a differential SPR. The detection limit by the SPR was 2 x 107 cell/ml to the sonicated sample, which showed much higher detection limit than unsonicated H.pyroli by 100 fold.

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49.

pHスタット型フローアンペロメトリックセンシングシステムによる尿素検出

藤野裕介，米山健司，逢坂哲彌，佐藤生男*

早稲田大学理工，早稲田大学材研，神奈川工科大工*

pH STATIC FLOW‐AMPEROMETRIC SENSING SYSTEM FOR THE DETECTION OF UREA

Yusuke FUJINO, Kenji YONEYAMA, Tetsuya OSAKA, and Ikuo SATOH*

Department of Applied Chemistry, School of Science and Engineering; Kagami Memorial Laboratory for Materials Science and Technology, Waseda University
Shinjyuku-ku, Tokyo 169- 8555, Japan
*Department of Applied Chemistry, Faculty of Engineering, Kanagawa Institute of Technology
Atsugi-shi, Kanagawa-ken 243-0292, Japan

A new type of amperometric urea sensing system based on pH static system and Flow Injection Analysis was constructed. In this system, the concentration of urea was determined by detecting the oxidation current of water producing H+, to compensate the consumption in the enzymatic reaction. The constructed system was confirmed to act sensitively and ideally by using alkaline sample. In this system, the urea response was not affected by the buffer concentration. The relationship between the urea concentration and the current response was found to be linear up to 600 ?M. Furthermore, the current response to the interfering substances was eliminated by separating the sample pass from the electrolysis pass.

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50.

尿素測定用アンペロメトリックセンサの作製

水谷文雄，佐藤　縁，矢吹聡一，飯島誠一郎

生命工研

CONSTRUCTION OF AMPEROMETRIC UREA-SENSING ENZYME ELECTRODE

Fumio MIZUTANI, Yukari SATO, Soichi YABUKI, and Seiichiro IIJIMA

National Institute of Bioscience and Human-Technology
1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan

An amperometric urea-sensing electrode was prepared by immobilizing urea amidolyase (UA) and pyruvate oxidase (PyOx) on a polyion complex layer-coated electrode. UA catalyzes the ATP-consuming hydrolysis of urea to form phosphate, and PyOx, the phosphate-depending oxidation of pyruvic acid to form hydrogen peroxide. The hydrogen peroxide produced is electrochemically oxidized to give an anodic current response. The UA/PyOx-couple was immobilized by using a photocrosslinkable polymer as the support. The inner, poly-L-lysine/poly(4-styrenesulfonate)-complex layer was useful as a size-exclusion film for the selective determination of hydrogen peroxide. The electrode could be used for measuring urea in the range of 0.5-100 μM. The relative standard deviation for ten successive measurement of 50 μM urea was 2.3%.

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51.

液膜型ＩＳＦＥＴによるニュートラルキャリヤー型電極における添加塩効果の応答機構

脇田慎一、正留　隆*、浅野泰一*、辻村　豊、吉川　暹

大阪工業技術研究所、有明工業高等専門学校*

RESPONSE MECHANISM OF ADDITIVE-SALT EFFECT ON ELECTROCHEMICAL CHARACTERISTICS OF NEUTRAL CARRIER BASED ELECTRODES USING THEIR LIQUID-MEMBRANE BASED ION-SELECTIVE FIELD-EFFECT TRANSISTORS

Shin-ichi WAKIDA, Takashi MASADOME*, Yasukazu ASANO*, Yutaka TSUJIMURA and Susumu YOSHIKAWA

Department of Energy and the Environment, Osaka National Research Institute, AIST
Ikeda, Osaka 563-8577, Japan
*Department of Chemical Science and Engineering, Ariake National College of Technology
Omuta, Fukuoka 836-8585, Japan

The remarkable effect of additive salts on low detection limits as well as slope sensitivities were observed for the response characteristics of bis(crown) and valinomycin based poly(vinyl chloride) (PVC) membrane electrodes. Their characteristics of the electrodes were improved apparently as the hydrophobicity of the additive salts increases. To clarify the effect, the response characteristics of the corresponding liquid-membrane based ion-selective field-effect transistors (ISFETs) were evaluated in detail. The obtained results suggest that the competitive reactions of complexation and ion-exchange occur at the surface of the sensing membrane.

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52.

電解重合薄膜の電気化学振動現象のセンシング素子への展開

福永勝則、木村美紀、石村　武、谷口　功

熊本大工

APPLICATION OF ELECTROCHEMICAL OSCILLATION OF ELECTROPOLYMERIZED THIN FILM TO SENSING DEVICES

Katsunori FUKUNAGA, Miki KIMURA, Takeshi ISHIMURA, and Isao TANIGUCHI

Department of Applied Chemistry & Biochemistry, Kumamoto University
Kurokami Kumamoto 860-8555, Japan

The electrochemical oscillation of the electropolymerized thin polypyrole film due to doping and undoping of ions to the film was applied to develop a new sensing device for various compounds as a model of biological sensing mechanisms. The films prepared under certain electrolysis conditions gave reproducible films for the oscillation behavior. The oscillation behavior was represented as a so-called atractor image, dI/dT vs. I (current). When acids such as HCl, H2SO4, CH3COOH, citric acid and other organic acids were added, the current oscillation-width increased with increasing the acid concentration, but the atractor pattern was different depending on the acid used. No significant change in oscillation pattern was observed for alkaline solutions (less than 0.01 M). Alcohol showed different behavior from that of acid, and 1- and 2-propylalcohol were distinguishable from the atractor pattern. Addition of sugars and some bitter-taste causing compounds made the current oscillation-width decreased. The change in oscillation pattern may be explained in terms of the difference in doping and undoping behavior caused by the penetration of protons (for acids) and by adsorption of compounds onto the film (alcohol, sugars etc.).

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53.

ＤＮＡ固定化グラファイトフェルトを感応素子とする変異原センサ

長谷部 靖、新井 雅己、山内 哲也、内山 俊一

埼玉工大・工

MUTANT SENSOR USING IMMOBILIZED-DNA GRAPHITE FELT AS A SENSING ELEMENT

Yasushi HASEBE, Masami ARAI, Tetsuya YAMAUCHI, and Shunichi UCHIYAMA

Department of Applied Chemistry, Saitama Institute of Technology
1690, Fusaiji, Okabe, Saitama,369-0293, Japan

DNA-based amperometric mutant sensor was proposed using DNA-immobilized graphite felt as a sensing element for intercalating drugs. Catalytic activity of DNA/Cu(II) complex for air oxidation of aminoethanthiol (AET) was reversibly inhibited by intercalation of mutants with DNA, which can be monitored by oxygen electrode. The peak-shape current responses of oxygen electrode detector were observed with FIA system consisted with immobilized DNA/Cu(II) reactor and AET-containing carrier.

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54.

抗体固定化磁性細菌粒子を利用した糖尿病診断用免疫測定の高感度化

田中　剛、中村徳幸、松永　是

東京農工大工

APPLICATION OF BACTERIAL MAGNETIC PARTICLES (BMPs) TO AUTOMATION OF IMMUNOASSAYS USED IN THE DIAGNOSIS OF DIABETES

Tsuyoshi TANAKA, Noriyuki NAKAMURA and Tadashi MATSUNAGA

Department of Biotechnology, Tokyo University of Agriculture and Technology
Koganei, Tokyo 184-8588, Japan

We report a sandwich immunoassay for evaluation of some analytes in the diagnosis of some analytes using antibody-conjugated bacterial magnetic particles (Ab-BMPs). A chemiluminescence enzyme immunoassay approach was adopted as this enables highly sensitive detection of analytes. For convenience approach and reliability, a fully-automated sandwich immunoassay approach using fully automated machine was adopted. The automated system consisted of a reaction station and an automatic pipettor. Antigen-antibody reactions were performed in the reaction station and the reaction mixture was dispersed by the automatic pipettor. Antigen-antibody complexes were separated magnetically from the immunoreaction mixture using a neodymium-boron (Nd-B) magnet. Antigen antibody complexes were finally resuspended in PBS and the luminescence yield was measured using a luminescence reader. A linear relationship was obtained between luminescence yield and antigen concentration. A highly-sensitive and simple automated assay was successfully achieved using BMPs and the fully-automated machine.

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55.

微小櫛型電極を使った免疫センサーの基礎研究

菊地正和、岩村大介、今川 宏

東洋大・工

INTERDIGITATED ARRAY ELECTRODES APPLIED TO IMMUNOSENSORS

Masakazu KIKUCHI, Daisuke IWAMURA, and Hiroshi IMAGAWA

Department of Applied Chemistry,Faculty of Engineering Toyo University
Kawagoe-shi,Saitama 350-8585, Japan

We prepared interdigitated array electrodes (IDAE) with sixty pairs of platinum arrays 1200 μm long and 5 μm wide by the electron beam lithography and photolithography. We determined their redox cycle numbers for ferrocene, ferrocianide, naphthol and others. Those numbers increased from 4 for the IDAE with 5 μm gaps upto 40 ± 10 for the IDAE with 0.5 μm gaps. Their small differences among redox species seems to reflect the differences in the diffusion constants. We coated those IDAE's with cross-linked mixture of glutaraldehyde, bovine serum albumin and Rabbit IgG as an antigen, then dipped them in alkaline phosphatase-labelled antirabbit IgG．Larger redox cycle numbers were observed for naphtol, which was produced by alkaline phosphatase label.

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56.

プラズマ重合膜によるキラル識別

黒澤　茂、Dirk Radloff、新保外志夫、吉本　稔*

物質研・金沢工大・鹿児島大*

CHIRAL RECOGINITION USING PLASMA-POLYMERIZED FILMS

Shigeru KUROSAWA, Dirk RADLOFF, Toshio SHINBO, and Minoru YOSHIMOTO

National Institute of Materials and Chemical Research
1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan

The characteristics of plasma-polymerized films synthesized from (1S)-(-)-α-pinene and (1R)-(+)-α-pinene, respectively, are discussed. We find that these films coated on quartz crystal microbalance (QCM) have good selectivity of chiral alcohols. It also becomes clear that the mechanism of the chiral selectivity depends on the structure and the chirarity of the alcohols.

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57.

マルチチャンネルQCMの開発（１）

立間　徹、渡辺能仁、小山　昇、北寄崎薫*、羽場方紀*

東京農工大工、明電舎*

DEVELOPMENT OF MULTICHANNEL QCM (1)

Tetsu TATSUMA, Yoshihito WATANABE, Noboru OYAMA, Kaoru KITAKIZAKI*, and Masanori HABA*

Department of Applied Chemistry, Faculty of Technology, Tokyo University of Agriculture and Technology
Koganei, Tokyo 184-8588, Japan
*Advanced Technology Research Laboratory, Meidensha Corporation
Ohsaki, Shinagawa-ku, Tokyo 141-8565, Japan

An array of quartz crystal resonators are fabricated on a single quartz wafer as a multichannel quartz crystal microbalance (MQCM). Three types of 4-channel array of 10-MHz resonators are prepared and tested. No significant interference is observed between the channels of each MQCM. Theoretically expected frequency changes are observed for electrodeposition of silver. Thus, each channel of a MQCM can be used as a conventional QCM.

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