JP2004069661A - Chemical sensor - Google Patents

Chemical sensor Download PDF

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Publication number
JP2004069661A
JP2004069661A JP2002233310A JP2002233310A JP2004069661A JP 2004069661 A JP2004069661 A JP 2004069661A JP 2002233310 A JP2002233310 A JP 2002233310A JP 2002233310 A JP2002233310 A JP 2002233310A JP 2004069661 A JP2004069661 A JP 2004069661A
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sensitive body
chemical sensor
detection
electrodes
frequency
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JP3884680B2 (en
Inventor
Shiro Yamauchi
山内　四郎
Osamu Takai
高井　治
Hiroyuki Sugimura
杉村　博之
Unei Go
呉　雲影
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Mitsubishi Electric Corp
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Mitsubishi Electric Corp
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Abstract

<P>PROBLEM TO BE SOLVED: To increase a deposit amount of objective gas onto a sensing element. <P>SOLUTION: In this chemical sensor, pairs of reference electrodes 8 and detecting electrodes 9 are formed respectively on a face of a quartz oscillator 7, and the porous sensing element 10 of a thin film is formed between the detecting electrodes 9 on the face of the quartz oscillator 7. Detection is allowed in a micro range of a several ppm level based on a proportional relation between a toluene gas concentration and a frequency variation fd when a difference of a reference transmission frequency fr between the reference electrodes 8 with respect to a detected transmission frequency fs between the detecting electrodes 9 is detected by a frequency detecting means 13. A surface area is increased because the sensing element 10 is porous, and the amount of the objective gas deposited on the sensing element 10 is increased thereby to enhance detection precision. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
この発明は、水晶振動子を使用した化学センサに関するものである。
【０００２】
【従来の技術】
現在、ＮＯｘ排ガスやダイオキシンを含む環境ホルモンによる環境汚染、建材からのホルムアルデヒド等の化学物質の放出によるシックハウス症候群が深刻な社会問題となっている。しかし、対象とする化学物質は極微量であり、ｐｐｍ〜ｐｐｔレベルの高感度の化学計測が必要である。
このような微量成分を検出できる従来の化学センサとして、図１０に示すように水晶振動子を用いたものがある。図１０において、水晶振動子１の面にそれぞれ一対の参照電極２と検出電極３とを形成し、さらに水晶振動子１の面の検出電極３間に測定対象ガスの吸着性を有する物質の感応体４を形成する。水晶振動子１は表面に物質が付着すると、付着した物質の質量に応じて発信周波数が減少する。そこで、参照電極２側の参照側発信周波数ｆｒを参照側発信周波数検出手段５ａで検出し、検出電極３側の検出側発信周波数ｆｓを検出側発信周波数検出手段５ｂで検出する。そして、両発信周波数ｆｒ，ｆｓの差である変動周波数ｆｄを周波数検出手段６で算出する。この変動周波数ｆｄは感応体４に付着した物質の量に比例するため、極微量のナノグラムレベルの質量変化を計測して、対象ガスの濃度を検出することができる。
【０００３】
【発明が解決しようとする課題】
従来の化学センサは以上のように構成されているので、対象ガスが低濃度の場合には感応体にはガスの付着量が少ないため、検出精度を向上させるのが困難であるという問題点があった。
この発明は、感応体への対象ガスの付着量を多くすることができる化学センサを提供することを目的としたものである。
【０００４】
【課題を解決するための手段】
この発明に係わる化学センサは、水晶振動子の面にそれぞれ一対の参照電極と検出電極とを形成し、水晶振動子の面の検出電極間に多孔性で薄膜の感応体を形成したものである。
また、感応体は塩基性を有するものである。
また、感応体は酸性を有するものである。
また、感応体は表面にアミノ基を含む層が形成され、アミノ基と最外層の抗体蛋白とをクロスリンカー分子を介して接合したものである。
さらに、感応体は撥水性を有するものである。
【０００５】
【発明の実施の形態】
実施の形態１．
図１は実施の形態１の構成を示す斜視図である。図１において、７は水晶振動子、８は一対の参照電極で、水晶振動子７の面に形成されている。９は一対の検出電極で、水晶振動子１の面に形成されている。１０は多孔性薄膜で形成された感応体で、水晶振動子７の面の検出電極９間に配置されている。なお、感応体１０は次の方法で形成されている。すなわち、導入原料のトリメチルメトキシラン（ＴＭＭＯＳ）とアルゴン（Ａｒ）に、マイクロ波出力３００Ｗ、圧力８０Ｐａで５分間マイクロ波プラズマを印加することにより、水晶振動子７の面に多孔性を有する薄膜の感応体１０を形成することができた。水晶振動子７の面に形成された薄膜の感応体１０は、表面が疎水性のメチル基で覆われているので、水滴接触角が１５０度以上あって撥水性を有する。なお、７〜１０で化学センサ１１が構成されている。
【０００６】
次に実験結果について説明する。図２は実験装置を示す説明図である。図１及び図２において、１２は密封された容積が５００ｍｌの容器で、内部に化学センサ１１が収納されている。さらに、容器１２には検出しようとする物質を入れる検出物質投入口１２ａ、Ｎ２ガスを入れるＮ２ガス投入口１２ｂ及び排出口１２ｃが設けられている。１３は化学センサ１１の各電極８，９と接続線８ａ，８ｂ，９ａ，９ｂを介して接続された周波数検出手段で、参照電極８間の参照発振周波数ｆｒと検出電極９間の検出発振周波数ｆｓとの差である周波数変動量ｆｄを算出する。
【０００７】
ここで、図３はトルエンに対する応答を示す説明図である。容器１２内に検出物質投入口１２ａからトルエンと水との割合を１対５０にした混合溶液を投入（ＯＮ）して気化させる。すると、トルエンが感応体１０に吸着されることにより検出電極９間の発振周波数が、図３の特性Ａに示すように周波数変動量ｆｄが１５０Ｈｚとなり大きく低下する。そして、Ｎ２ガス投入口１２ｂからＮ２ガスを投入してトルエンガスを排出（ＯＦＦ）すると、周波数変動量がトルエンを投入（ＯＮ）する前の状態に復帰した。なお、図３の特性Ｂは比較のために示したもので、水だけを容器１２内に投入（ＯＮ）して気化させたときの応答である。この場合、感応体１０が疎水性（撥水性）を有するので、相対湿度１００％でも影響が抑制されている。なお、この実験に使用した化学センサ１１の感応体１０の膜圧は２８３ｎｍである。
【０００８】
図４はトルエンガスに対する化学センサ１１の検出特性を示す説明図である。図４は周波数検出手段１３により検出された参照電極８間の参照発信周波数ｆｒと、検出電極９間の検出発振周波数ｆｓとの差である周波数変動量ｆｄを示す。図４によると、トルエンガス濃度と周波数変動量ｆｄとが比例関係にあり、数ｐｐｍレベルの微量域においても検出可能である。
次に、ホルムアルデヒドの検出について説明する。図５はホルムアルデヒドに対する応答を示す説明図である。図１、図２及び図５において、容器１２内に検出物質投入口１２ａから、３７％ホルムアルデヒド、８％メタノール、５５％水の組成溶液１ｍｌを１０ｍｌの純粋に混合した溶液を投入して気化（ＯＮ）させる。
【０００９】
この気化した蒸気内での化学センサ１１のホルムアルデヒドに対する応答を図５に示す。ホルムアルデヒドが感応体１０に吸着されることにより、検出電極９間の発振周波数が図５の特性Ａに示すように周波数変動量ｆｄが１３０Ｈｚと大きく低下する。そして、Ｎ２ガス投入口１２ｂからＮ２ガスを投入してホルムアルデヒドガスを排出（ＯＦＦ）すると、ホルムアルデヒドを投入（ＯＮ）する前の状態に復帰した。図５の特性Ｂは比較のために示したもので、水だけを容器１２内に投入（ＯＮ）して気化させたときの応答で、図３の特性Ｂと同様である。なお、この実験に使用した化学センサ１１の感応体１０の膜圧は２８３ｎｍである。
図６は周波数検出手段１３により検出された参照電極８間の参照発信周波数ｆｒと、検出電極９間の検出発振周波数ｆｓとの差である周波数変動量ｆｄを示す。図６によると、ホルムアルデヒドガス濃度と周波数変動量ｆｄとが比例関係にあり、数ｐｐｍレベルの微量域においても検出可能である。
【００１０】
以上のように、水晶振動子７の面にそれぞれ一対の参照電極８と検出電極９とを形成し、検出電極９間に多孔性で薄膜の感応体１０を形成したことにより、感応体１０の表面積が増大して感応体１０へ付着する検出対象ガスが多くなるので、検出精度の向上を図ることができる。
さらに、感応体１０は撥水性を有するので、相対湿度１００％でも影響を抑制することができる。
実施の形態１において、トルエン（Ｃ７Ｈ８）、ホルムアルデヒド（ＨＣＨＯ）を検出するものについて説明したが、ベンゼン等の有機ガスについても同様の効果を期待することができる。
【００１１】
実施の形態２．
図７は実施の形態２の構成を示す斜視図である。図７において、７〜９は実施の形態１のものと同様のものである。１４は多孔性薄膜で形成された感応体で、水晶振動子７の面の検出電極９間に配置されている。ここで、感応体１４は次の方法で形成されている。すなわち、導入原料のアルミニウム（ＩＩＩ）アミノｎ−ブトキサイドとアルゴン（Ａｒ）に、マイクロ波出力３００Ｗ、圧力８０Ｐａで５分間マイクロ波プラズマを印加することにより、水晶振動子７の面に多孔性で撥水性を有する薄膜の塩基性の感応体１４を形成することができた。なお、７〜９，１４で化学センサ１５が構成されている。水晶振動子７の面に形成された感応体１４は塩基性を示すので、酸性ガスの検出に適している。そして、図２の実験装置で実験した結果ではｐｐｍレベルの微量のＮＯ２の検出に有効であることが判明した。
【００１２】
以上のように、検出電極９間に多孔性で薄膜の感応体１４を形成したことにより、感応体１４の表面積が増大して感応体１４へ付着する検出対象ガスが多くなるので、検出精度の向上を図ることができる。さらに、塩基性を有する感応体１４を形成することにより、酸性ガスの検出を行うことができる。
さらに、感応体１４は撥水性を有するので、相対湿度１００パーセントでも影響を抑制することができる。
実施の形態２において、ＮＯ２　（二酸化窒素）の検出について説明したが、ＳＯ２（二酸化硫黄）、Ｈ２Ｓ（硫化水素）等の酸性ガスについても同様の効果を期待することができる。
【００１３】
実施の形態３．
図８は実施の形態３の構成を示す斜視図である。図８において、７〜９は実施の形態１のものと同様のものである。１６は多孔性薄膜で形成された感応体で、水晶振動子７の面の検出電極９間に配置されている。ここで、感応体１６は次の方法で形成されている。すなわち、導入原料のアルミニウム（ＩＩＩ）ｎ−プトキサイドとアルゴン（Ａｒ）に、マイクロ波出力３００Ｗ、圧力８０Ｐａで５分間マイクロ波プラズマを印加することにより、水晶振動子７の面に多孔性で撥水性を有する塩基性の薄膜を形成し、薄膜の表面に硝酸蒸気を暴露して硝酸を化学吸着させた感応体１６とした。これにより、感応体１６は酸性状態に形成したので、塩基性ガスの吸着に適している。なお、７〜９，１６で化学センサ１７が構成されている。
化学センサ１７を図２の実験装置で実験した結果では、ｐｐｍレベルの微量のトリメチルアミン（ＣＨ３）３Ｎ、アンモニアＮＨ３、アニリンＣ６Ｈ７Ｎ等の有機性ガスの検出に有効であることが判明した。
以上のように、感応体１６を多孔性を有するものに形成したことにより、感応体１６へ検出対象ガスの付着量が多くなるため検出精度の向上を図ることができる。さらに、感応体１６を酸性状態に形成したことにより、塩基性ガスの検出を行うことができる。
さらに、感応体１６は撥水性を有するので、相対湿度１００パーセントでも影響を抑制することができる。
【００１４】
実施の形態４．
図９は実施の形態４の構成を示す斜視図である。図９において、７〜９は実施の形態１のものと同様のものである。１８は多孔性薄膜で形成された感応体で、水晶振動子７の面の検出電極９間に配置されている。ここで、感応体１８は次の方法で形成されている。すなわち、導入原料のトリメチルメトキシラン（ＴＭＭＯＳ）とアルゴン（Ａｒ）に、マイクロ波出力３００Ｗ、圧力８０Ｐａで５分間マイクロ波プラズマを印加することにより、水晶振動子７の面に多孔性を有する薄膜を形成する。続いて、プラズマ印加により形成された薄膜の表面にアミノ基を含む層を形成し、アミノ基と最外層のダイオキシン（抗原）に対する抗体蛋白とをクロスリンカー分子を介して接合することにより感応体１８が得られる。なお、７〜９，１８で化学センサ１９が構成されている。
化学センサ１９を図２の実験装置で実験した結果では、微量のダイオキシンの検出に有効であることが判明した。
【００１５】
以上のように、感応体１８に抗体蛋白を接合させたことにより、抗体蛋白に対応した抗原を検出することができる。
さらに、感応体１８は撥水性を有するので、相対湿度１００パーセントでも影響を抑制することができる。
実施の形態４において、感応体１８の最外層にダイオキシン（抗原）に対する抗体蛋白を配置したものについて説明したが、環境ホルモンであるポリ塩化ダイオキシン、ポリ塩化ジベンゾフラン、ベンゾフェノン、ｎ−ブチルベンゼン、エチルパラチオン等の抗原に対応した抗体蛋白を配置することにより、それぞれの対象物質を検出することができる。
【００１６】
【発明の効果】
この発明によれば、水晶振動子の面にそれぞれ一対の参照電極と検出電極とを形成し、検出電極間に多孔性で薄膜の感応体を形成したことにより、感応体の表面積が増大して感応体へ付着する検出対象ガスが多くなるので、検出精度の向上を図ることができる。
また、塩基性を有する感応体を形成したことにより、酸性ガスの検出を行うことができる。
また、感応体を酸性状態に形成したことにより、塩基性ガスの検出を行うことができる。
また、感応体に抗体蛋白を接合させたことにより、抗体蛋白に対応した抗原を検出することができる。
さらに、感応体が撥水性を有するので、相対湿度１００パーセントでも影響を抑制することができる。
【図面の簡単な説明】
【図１】この発明の実施の形態１の構成を示す斜視図である。
【図２】化学センサの実験装置を示す説明図である。
【図３】実施の形態１のトルエンに対する応答を示す説明図である。
【図４】実施の形態１のトルエンガスに対する化学センサの検出特性を示す説明図である。
【図５】実施の形態１の化学センサのホルムアルデヒドに対する応答を示す説明図である。
【図６】実施の形態１のホルムアルデヒドガスに対する化学センサの検出特性を示す説明図である。
【図７】この発明の実施の形態２の構成を示す斜視図である。
【図８】この発明の実施の形態３の構成を示す斜視図である。
【図９】この発明の実施の形態４の構成を示す斜視図である。
【図１０】従来の化学センサの構成を示す斜視図である。
【符号の説明】
７　水晶振動子、８　参照電極、９　検出電極、
１０，１４，１６，１８　感応体、１１，１５，１７，１９　化学センサ。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a chemical sensor using a quartz oscillator.
[0002]
[Prior art]
At present, environmental pollution by environmental hormones including NOx exhaust gas and dioxin, and sick house syndrome due to release of chemical substances such as formaldehyde from building materials have become serious social problems. However, the target chemical substance is very small, and high-sensitivity chemical measurement at the ppm to ppt level is required.
As a conventional chemical sensor capable of detecting such a trace component, there is a sensor using a quartz oscillator as shown in FIG. In FIG. 10, a pair of reference electrodes 2 and detection electrodes 3 are formed on the surface of the crystal unit 1, respectively. The body 4 is formed. When a substance adheres to the surface of the crystal unit 1, the transmission frequency decreases in accordance with the mass of the adhered substance. Therefore, the reference-side transmission frequency fr on the reference electrode 2 side is detected by the reference-side transmission frequency detection unit 5a, and the detection-side transmission frequency fs on the detection electrode 3 side is detected by the detection-side transmission frequency detection unit 5b. Then, the fluctuating frequency fd, which is the difference between the two transmitting frequencies fr and fs, is calculated by the frequency detecting means 6. Since the fluctuation frequency fd is proportional to the amount of the substance adhering to the sensitive body 4, it is possible to detect the concentration of the target gas by measuring a very small nanogram-level change in mass.
[0003]
[Problems to be solved by the invention]
Since the conventional chemical sensor is configured as described above, when the target gas has a low concentration, there is a problem that it is difficult to improve the detection accuracy because the amount of gas adhering to the sensitive body is small. there were.
An object of the present invention is to provide a chemical sensor that can increase the amount of target gas adhering to a sensitive body.
[0004]
[Means for Solving the Problems]
The chemical sensor according to the present invention is such that a pair of reference electrodes and a detection electrode are formed on the surface of a quartz oscillator, and a porous thin-film sensitive body is formed between the detection electrodes on the surface of the quartz oscillator. .
Further, the sensitizer has basicity.
Further, the sensitive body has acidity.
The sensitizer has an amino group-containing layer formed on the surface, and the amino group and the outermost antibody protein are bonded via a crosslinker molecule.
Further, the sensitive body has water repellency.
[0005]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiment 1 FIG.
FIG. 1 is a perspective view showing the configuration of the first embodiment. In FIG. 1, reference numeral 7 denotes a quartz oscillator, and 8 denotes a pair of reference electrodes, which are formed on the surface of the quartz oscillator 7. Reference numeral 9 denotes a pair of detection electrodes formed on the surface of the crystal unit 1. Reference numeral 10 denotes a sensitive body formed of a porous thin film, which is disposed between the detection electrodes 9 on the surface of the crystal unit 7. The sensitive body 10 is formed by the following method. That is, by applying microwave plasma at a microwave output of 300 W and a pressure of 80 Pa for 5 minutes to trimethylmethoxylane (TMMOS) and argon (Ar) as the introduced raw materials, a porous thin film is formed on the surface of the quartz vibrator 7. The sensitive body 10 was able to be formed. Since the surface of the thin film sensitive body 10 formed on the surface of the crystal unit 7 is covered with a hydrophobic methyl group, the water sensitive body has a water droplet contact angle of 150 degrees or more and has water repellency. The chemical sensor 11 is composed of 7 to 10.
[0006]
Next, experimental results will be described. FIG. 2 is an explanatory view showing the experimental apparatus. 1 and 2, reference numeral 12 denotes a sealed container having a capacity of 500 ml, in which a chemical sensor 11 is housed. Furthermore, the detection material input port 12a to put the substance to be detected, N 2 gas inlet 12b and outlet 12c add N 2 gas is provided in the container 12. Reference numeral 13 denotes frequency detecting means connected to the electrodes 8 and 9 of the chemical sensor 11 via connection lines 8a, 8b, 9a and 9b. The reference oscillation frequency fr between the reference electrodes 8 and the detection oscillation frequency between the detection electrodes 9 are provided. The frequency variation fd, which is the difference from fs, is calculated.
[0007]
Here, FIG. 3 is an explanatory diagram showing a response to toluene. A mixed solution in which the ratio of toluene and water is 1:50 is charged (ON) into the container 12 from the detection substance charging port 12a and vaporized. Then, as the toluene is adsorbed on the sensitive body 10, the oscillation frequency between the detection electrodes 9 becomes significantly lower as the frequency variation fd becomes 150 Hz as shown by the characteristic A in FIG. Then, when N 2 gas was introduced from the N 2 gas inlet 12b and toluene gas was discharged (OFF), the frequency fluctuation amount returned to the state before the toluene was supplied (ON). The characteristic B in FIG. 3 is shown for comparison and is a response when only water is charged (ON) into the container 12 and vaporized. In this case, since the sensitive body 10 has hydrophobicity (water repellency), the influence is suppressed even when the relative humidity is 100%. The film pressure of the sensitive body 10 of the chemical sensor 11 used in this experiment is 283 nm.
[0008]
FIG. 4 is an explanatory diagram showing detection characteristics of the chemical sensor 11 with respect to toluene gas. FIG. 4 shows a frequency fluctuation amount fd which is a difference between the reference oscillation frequency fr between the reference electrodes 8 detected by the frequency detection means 13 and the detected oscillation frequency fs between the detection electrodes 9. According to FIG. 4, the toluene gas concentration and the frequency fluctuation amount fd are in a proportional relationship, and can be detected even in a trace range of several ppm level.
Next, detection of formaldehyde will be described. FIG. 5 is an explanatory diagram showing a response to formaldehyde. 1, 2 and 5, 10 ml of a purely mixed solution of 1 ml of a 37% formaldehyde, 8% methanol, and 55% water composition solution is introduced into the container 12 from the detection substance introduction port 12a and vaporized ( ON).
[0009]
FIG. 5 shows the response of the chemical sensor 11 to formaldehyde in the vaporized vapor. As the formaldehyde is adsorbed on the sensitive body 10, the oscillation frequency between the detection electrodes 9 greatly decreases as the frequency variation fd becomes 130 Hz as shown by the characteristic A in FIG. Then, when N 2 gas was introduced from the N 2 gas inlet 12b and formaldehyde gas was discharged (OFF), the state returned to the state before the formaldehyde was supplied (ON). The characteristic B in FIG. 5 is shown for comparison, and is a response when only water is charged (ON) into the container 12 and vaporized, and is similar to the characteristic B in FIG. The film pressure of the sensitive body 10 of the chemical sensor 11 used in this experiment is 283 nm.
FIG. 6 shows a frequency fluctuation amount fd which is a difference between the reference oscillation frequency fr between the reference electrodes 8 detected by the frequency detection means 13 and the detection oscillation frequency fs between the detection electrodes 9. According to FIG. 6, there is a proportional relationship between the formaldehyde gas concentration and the frequency variation fd, and detection is possible even in a trace range of several ppm level.
[0010]
As described above, the pair of reference electrodes 8 and the detection electrodes 9 are formed on the surface of the crystal resonator 7, and the porous thin-film sensitizer 10 is formed between the detection electrodes 9. Since the surface area increases and the detection target gas attached to the sensitive body 10 increases, the detection accuracy can be improved.
Further, since the sensitive body 10 has water repellency, the influence can be suppressed even when the relative humidity is 100%.
In the first embodiment, the case where toluene (C7H8) and formaldehyde (HCHO) are detected has been described. However, the same effect can be expected for an organic gas such as benzene.
[0011]
Embodiment 2 FIG.
FIG. 7 is a perspective view showing the configuration of the second embodiment. In FIG. 7, 7 to 9 are the same as those in the first embodiment. Reference numeral 14 denotes a sensitive body formed of a porous thin film, which is arranged between the detection electrodes 9 on the surface of the crystal unit 7. Here, the sensitive body 14 is formed by the following method. That is, by applying microwave plasma at a microwave output of 300 W and a pressure of 80 Pa for 5 minutes to aluminum (III) amino n-butoxide and argon (Ar) as the raw materials to be introduced, the surface of the crystal unit 7 is porous and repelled. An aqueous thin-film basic sensitizer 14 could be formed. The chemical sensor 15 is composed of 7 to 9, 14. Since the sensitive body 14 formed on the surface of the crystal resonator 7 exhibits basicity, it is suitable for detecting an acidic gas. Then, the result of the experiment using the experimental apparatus shown in FIG. 2 proved to be effective in detecting a trace amount of NO 2 at a ppm level.
[0012]
As described above, by forming the porous thin-film sensitive body 14 between the detection electrodes 9, the surface area of the sensitive body 14 increases, and the detection target gas attached to the sensitive body 14 increases. Improvement can be achieved. Further, by forming the sensitive body 14 having basicity, the detection of an acidic gas can be performed.
Further, since the sensitive body 14 has water repellency, the influence can be suppressed even when the relative humidity is 100%.
In the second embodiment, detection of NO 2 (nitrogen dioxide) has been described. However, similar effects can be expected for acidic gases such as SO 2 (sulfur dioxide) and H 2 S (hydrogen sulfide).
[0013]
Embodiment 3 FIG.
FIG. 8 is a perspective view showing the configuration of the third embodiment. In FIG. 8, reference numerals 7 to 9 are the same as those in the first embodiment. Reference numeral 16 denotes a sensitive body formed of a porous thin film, which is arranged between the detection electrodes 9 on the surface of the crystal unit 7. Here, the sensitive body 16 is formed by the following method. That is, by applying microwave plasma at a microwave output of 300 W and a pressure of 80 Pa for 5 minutes to aluminum (III) n-butoxide and argon (Ar) as the introduced raw materials, the surface of the crystal unit 7 is porous and water-repellent. Was formed, and the surface of the thin film was exposed to a nitric acid vapor to obtain a sensitizer 16 in which nitric acid was chemically adsorbed. As a result, the sensitive body 16 is formed in an acidic state, and thus is suitable for adsorption of a basic gas. In addition, the chemical sensor 17 is comprised by 7-9,16.
The chemical sensor 17 in the results of an experiment in the experimental apparatus of FIG. 2, the ppm level of trace trimethylamine (CH 3) 3 N, ammonia NH 3, it is effective for the detection of organic gases such as aniline C 6 H 7 N There was found.
As described above, by forming the sensitive body 16 to be porous, the amount of gas to be detected attached to the sensitive body 16 increases, so that the detection accuracy can be improved. Further, since the sensitive body 16 is formed in an acidic state, a basic gas can be detected.
Further, since the sensitive body 16 has water repellency, the influence can be suppressed even when the relative humidity is 100%.
[0014]
Embodiment 4 FIG.
FIG. 9 is a perspective view showing the configuration of the fourth embodiment. In FIG. 9, reference numerals 7 to 9 are the same as those in the first embodiment. Reference numeral 18 denotes a sensitive body formed of a porous thin film, which is arranged between the detection electrodes 9 on the surface of the crystal unit 7. Here, the sensitive body 18 is formed by the following method. That is, by applying microwave plasma at a microwave output of 300 W and a pressure of 80 Pa for 5 minutes to trimethylmethoxylane (TMMOS) and argon (Ar) as introduced raw materials, a porous thin film is formed on the surface of the crystal unit 7. Form. Subsequently, a layer containing an amino group is formed on the surface of the thin film formed by applying the plasma, and the amino group and an antibody protein against dioxin (antigen) in the outermost layer are joined via a crosslinker molecule to thereby form the sensitizer 18. Is obtained. In addition, the chemical sensor 19 is comprised by 7-9,18.
The results of experiments on the chemical sensor 19 using the experimental apparatus shown in FIG. 2 proved to be effective in detecting trace amounts of dioxin.
[0015]
As described above, by attaching the antibody protein to the sensitizer 18, an antigen corresponding to the antibody protein can be detected.
Further, since the sensitive body 18 has water repellency, the influence can be suppressed even when the relative humidity is 100%.
In the fourth embodiment, an example in which an antibody protein against dioxin (antigen) is arranged on the outermost layer of the sensitizer 18 has been described. By arranging antibody proteins corresponding to the antigens, etc., each target substance can be detected.
[0016]
【The invention's effect】
According to the present invention, a pair of reference electrodes and a detection electrode are respectively formed on the surface of the quartz oscillator, and a porous and thin-film sensitive body is formed between the detection electrodes, so that the surface area of the sensitive body is increased. Since the detection target gas attached to the sensitive body increases, the detection accuracy can be improved.
In addition, the formation of the basic sensitizer enables the detection of an acidic gas.
Further, by forming the sensitive body in an acidic state, it is possible to detect a basic gas.
In addition, by attaching the antibody protein to the sensitizer, an antigen corresponding to the antibody protein can be detected.
Further, since the sensitive body has water repellency, the influence can be suppressed even when the relative humidity is 100%.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a configuration of a first embodiment of the present invention.
FIG. 2 is an explanatory view showing an experimental device for a chemical sensor.
FIG. 3 is an explanatory diagram showing a response to toluene according to the first embodiment.
FIG. 4 is an explanatory diagram showing detection characteristics of a chemical sensor for toluene gas according to the first embodiment.
FIG. 5 is an explanatory diagram showing a response of the chemical sensor according to the first embodiment to formaldehyde.
FIG. 6 is an explanatory diagram showing detection characteristics of a chemical sensor for formaldehyde gas according to the first embodiment.
FIG. 7 is a perspective view showing a configuration of a second embodiment of the present invention.
FIG. 8 is a perspective view showing a configuration of a third embodiment of the present invention.
FIG. 9 is a perspective view showing a configuration of a fourth embodiment of the present invention.
FIG. 10 is a perspective view showing a configuration of a conventional chemical sensor.
[Explanation of symbols]
7 crystal oscillator, 8 reference electrode, 9 detection electrode,
10, 14, 16, 18 Sensitive body, 11, 15, 17, 19 Chemical sensor.

Claims (5)

水晶振動子の面にそれぞれ一対の参照電極と検出電極とを形成し、上記水晶振動子の面の上記検出電極間に多孔性で薄膜の感応体を形成したことを特徴とする化学センサ。A chemical sensor comprising: a pair of reference electrodes and a detection electrode formed on a surface of a quartz oscillator; and a porous thin-film sensitive body formed between the detection electrodes on the surface of the quartz oscillator. 請求項１において、上記感応体は塩基性を有することを特徴とする化学センサ。2. The chemical sensor according to claim 1, wherein the sensitive body has basicity. 請求項１において、上記感応体は酸性を有するものであることを特徴とする化学センサ。2. The chemical sensor according to claim 1, wherein the sensitive body has acidity. 請求項１において、上記感応体は表面にアミノ基を含む層が形成され、上記アミノ基と最外層の抗体蛋白とをクロスリンカー分子を介して接合したものであることを特徴とする化学センサ。2. The chemical sensor according to claim 1, wherein the sensitizer has a layer containing an amino group formed on the surface thereof, and the amino group and the outermost antibody protein are bonded via a crosslinker molecule. 請求項１において、上記感応体は撥水性を有することを特徴とする化学センサ。The chemical sensor according to claim 1, wherein the sensitive body has water repellency.
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007240252A (en) * 2006-03-07 2007-09-20 National Institute Of Advanced Industrial & Technology Detection sensor, and oscillator
JP2013044579A (en) * 2011-08-23 2013-03-04 Nagoya Institute Of Technology Method of hydrophobizing zeolite containing metal complex, and sensor obtained by the method
US9791412B2 (en) 2013-06-12 2017-10-17 Nihon Dempa Kogyo Co., Ltd. Sensing device
WO2018221283A1 (en) * 2017-05-31 2018-12-06 国立研究開発法人物質・材料研究機構 Nanomechanical-sensor receptor made of low-hygroscopicity material and nanomechanical sensor employing same as receptor

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03140838A (en) * 1989-10-26 1991-06-14 Brother Ind Ltd Gas sensor
JPH0545339A (en) * 1991-08-09 1993-02-23 Tokimec Inc Elastic wave element and measuring apparatus of physical property of solution using the element
JPH0545338A (en) * 1991-08-09 1993-02-23 Tokimec Inc Elastic wave element and measuring apparatus of physical property of solution using the element
JPH05281120A (en) * 1991-03-25 1993-10-29 Fuji Xerox Co Ltd Gas detecting apparatus
JPH05312707A (en) * 1992-05-06 1993-11-22 Nippon Soken Inc Gas sensor
JPH06165933A (en) * 1992-09-29 1994-06-14 Mitsubishi Electric Corp Nitrogen oxide selectively adsorbing material reaction control method therefor and device for detecting, adsorption-removing and decomposing gas using them
JPH0894510A (en) * 1994-09-27 1996-04-12 Oki Electric Ind Co Ltd Odor detecting method, odor sensor and its manufacture
JPH09131335A (en) * 1995-11-08 1997-05-20 Nippon Telegr & Teleph Corp <Ntt> Individual identifying method and individual identifying device
JPH09189685A (en) * 1996-01-05 1997-07-22 Mitsubishi Electric Corp Gas sensor using self-reproducing gas-sensitive film
JP2000304672A (en) * 1999-04-16 2000-11-02 Agency Of Ind Science & Technol Variable sensitivity detection method of substance to be detected using crystal oscillator

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03140838A (en) * 1989-10-26 1991-06-14 Brother Ind Ltd Gas sensor
JPH05281120A (en) * 1991-03-25 1993-10-29 Fuji Xerox Co Ltd Gas detecting apparatus
JPH0545339A (en) * 1991-08-09 1993-02-23 Tokimec Inc Elastic wave element and measuring apparatus of physical property of solution using the element
JPH0545338A (en) * 1991-08-09 1993-02-23 Tokimec Inc Elastic wave element and measuring apparatus of physical property of solution using the element
JPH05312707A (en) * 1992-05-06 1993-11-22 Nippon Soken Inc Gas sensor
JPH06165933A (en) * 1992-09-29 1994-06-14 Mitsubishi Electric Corp Nitrogen oxide selectively adsorbing material reaction control method therefor and device for detecting, adsorption-removing and decomposing gas using them
JPH0894510A (en) * 1994-09-27 1996-04-12 Oki Electric Ind Co Ltd Odor detecting method, odor sensor and its manufacture
JPH09131335A (en) * 1995-11-08 1997-05-20 Nippon Telegr & Teleph Corp <Ntt> Individual identifying method and individual identifying device
JPH09189685A (en) * 1996-01-05 1997-07-22 Mitsubishi Electric Corp Gas sensor using self-reproducing gas-sensitive film
JP2000304672A (en) * 1999-04-16 2000-11-02 Agency Of Ind Science & Technol Variable sensitivity detection method of substance to be detected using crystal oscillator

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007240252A (en) * 2006-03-07 2007-09-20 National Institute Of Advanced Industrial & Technology Detection sensor, and oscillator
JP2013044579A (en) * 2011-08-23 2013-03-04 Nagoya Institute Of Technology Method of hydrophobizing zeolite containing metal complex, and sensor obtained by the method
US9791412B2 (en) 2013-06-12 2017-10-17 Nihon Dempa Kogyo Co., Ltd. Sensing device
WO2018221283A1 (en) * 2017-05-31 2018-12-06 国立研究開発法人物質・材料研究機構 Nanomechanical-sensor receptor made of low-hygroscopicity material and nanomechanical sensor employing same as receptor

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