JPH0515220B2 - - Google Patents
Info
- Publication number
- JPH0515220B2 JPH0515220B2 JP62080431A JP8043187A JPH0515220B2 JP H0515220 B2 JPH0515220 B2 JP H0515220B2 JP 62080431 A JP62080431 A JP 62080431A JP 8043187 A JP8043187 A JP 8043187A JP H0515220 B2 JPH0515220 B2 JP H0515220B2
- Authority
- JP
- Japan
- Prior art keywords
- diffusion
- membrane
- limiting
- substance
- enzyme
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000012528 membrane Substances 0.000 claims description 56
- 239000000126 substance Substances 0.000 claims description 34
- 108090000790 Enzymes Proteins 0.000 claims description 21
- 102000004190 Enzymes Human genes 0.000 claims description 21
- 230000000694 effects Effects 0.000 claims description 12
- 108010093096 Immobilized Enzymes Proteins 0.000 claims description 8
- 239000013543 active substance Substances 0.000 claims description 3
- 239000002245 particle Substances 0.000 claims description 2
- 238000009792 diffusion process Methods 0.000 description 20
- 239000010408 film Substances 0.000 description 19
- 229940088598 enzyme Drugs 0.000 description 18
- 238000005259 measurement Methods 0.000 description 17
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 16
- 239000008103 glucose Substances 0.000 description 16
- 230000000670 limiting effect Effects 0.000 description 15
- 230000002452 interceptive effect Effects 0.000 description 14
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 8
- 108010015776 Glucose oxidase Proteins 0.000 description 5
- 239000004366 Glucose oxidase Substances 0.000 description 5
- 230000000052 comparative effect Effects 0.000 description 5
- 229940116332 glucose oxidase Drugs 0.000 description 5
- 235000019420 glucose oxidase Nutrition 0.000 description 5
- 229920000298 Cellophane Polymers 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 239000001301 oxygen Substances 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 102000004169 proteins and genes Human genes 0.000 description 3
- 108090000623 proteins and genes Proteins 0.000 description 3
- 239000013076 target substance Substances 0.000 description 3
- 238000002834 transmittance Methods 0.000 description 3
- 239000012491 analyte Substances 0.000 description 2
- 210000004027 cell Anatomy 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 150000002894 organic compounds Chemical class 0.000 description 2
- 239000010409 thin film Substances 0.000 description 2
- RGHNJXZEOKUKBD-UHFFFAOYSA-N D-gluconic acid Natural products OCC(O)C(O)C(O)C(O)C(O)=O RGHNJXZEOKUKBD-UHFFFAOYSA-N 0.000 description 1
- RGHNJXZEOKUKBD-SQOUGZDYSA-N Gluconic acid Natural products OC[C@@H](O)[C@@H](O)[C@H](O)[C@@H](O)C(O)=O RGHNJXZEOKUKBD-SQOUGZDYSA-N 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 230000000975 bioactive effect Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 210000004369 blood Anatomy 0.000 description 1
- 239000008280 blood Substances 0.000 description 1
- 210000000601 blood cell Anatomy 0.000 description 1
- 210000002808 connective tissue Anatomy 0.000 description 1
- 235000012208 gluconic acid Nutrition 0.000 description 1
- 239000000174 gluconic acid Substances 0.000 description 1
- 229920000620 organic polymer Polymers 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
Description
＜産業上の利用分野＞
この発明は酵素電極に関し、さらに詳細にいえ
ば、拡散制限膜により測定対象物質の拡散を制限
し、拡散が制限された物質を固定化酵素膜に導く
ようにした酵素電極に関する。
＜従来の技術＞
従来から非常に複雑な有機化合物、蛋白質等を
極めて高感度に、かつ選択的に検知することがで
きるという特質に着目して、電極の表面に生理活
性物質を固定してなる酵素電極により上記有機化
合物、蛋白質等の測定を行なうための研究開発が
行なわれている。
そして、上記酵素電極を使用して対象物質の測
定を行なう場合には、電極の表面に固定されてい
る酵素により測定対象物質の酸化、或は還元が行
なわれるので、酸化、還元の結果変化する酸素濃
度、過酸化水素濃度等を測定することにより、間
接的に測定対象物質の濃度を知ることができるの
である。具体的には、グルコース濃度の測定を行
なう場合には、生理活性物質としてグルコースオ
キシダーゼ（GOD）を使用すればよく、
グルコース＋O2＋H2OGOD
―――→
グルコン酸＋H2O2
なる反応が行なわれるので、溶存酸素濃度の減
少、或は過酸化水素濃度の増加を検出することよ
りグルコース濃度を知ることができる。
また、上記反応式から明らかなように、グルコ
ース濃度の測定限界は測定対象溶液中における酸
素量に基づいて定まるのであるから、グルコース
オキシダーゼに到達するグルコース量を制限する
ことにより測定限界を拡張することが着目され、
特開昭59−22620号公報に示されるように、グル
コース制限透過膜が提案されるに至つている。
尚、以上には主としてグルコース濃度を測定す
る場合について説明したが、他の有機高分子、蛋
白質等の濃度を測定する場合についても同様であ
る。
また、内膜層、酵素層、電気伝導層、および外
膜層がこの順に積層された構成の薄層セル（特開
昭57−73667号公報参照）、電極を含む酵素層を挟
んで内膜を対称に配置し、各内膜の外側に外膜を
配置した構成の薄層セル（特開昭57−73667号公
報参照）、酵素を固定化し、かつ導電性薄膜を形
成した第１の多孔質膜と、妨害物質除去用の導電
性薄膜を形成した第２の多孔質膜と、両多孔質膜
の間に介在する絶縁用多孔質膜とを有する構成
（特開昭57−211054号公報参照）、および第１隔膜
と第２隔膜とをリング状フイルムを介在させるこ
とにより接着一体化しており、リング状フイルム
および両隔膜で形成される空間に酵素を含むゲル
状物質を収容した構成の積層膜（特開昭57−
74653号公報参照）が高分子物質等の妨害物質を
排除できる構成として提案されている。
＜発明が解決しようとする問題点＞
特開昭59−22620号公報に示される酵素電極に
おいては、測定対象物質を含む溶液が他の大きな
粒径の妨害物質をも含んでいる場合に、拡散制限
膜により測定対象物の拡散を制限する他に、妨害
物質の透過を阻止することができ、広範囲にわた
る測定対象物質濃度の測定を正確に行なうことが
できる。
また、特開昭57−73667号公報、特開昭57−
211054号公報、特開昭57−74653号公報に示され
る構成を採用した場合にも、十分な妨害物質の透
過阻止効果およびある程度の測定対象物質の拡散
制限効果を達成できる。
特開昭59−22620号公報に示す構成を採用して、
１回測定動作を遂行すると、拡散制限膜に妨害物
質がかなり多量に付着し、そのままでは２回目以
降の測定を正確には行ない得ないことになるの
で、所定回数の測定を行なう毎に、好ましくは１
回の測定を行なう毎に拡散制限膜を交換し、妨害
物質の影響を受けない状態での測定を行なうこと
ができるようにしている。したがつて、交換され
る拡散制限膜自体の特性のばらつき、および取付
状態のばらつきが存在しなければ、妨害物質の影
響を排除して、正確な測定を行なうことができ
る。
しかし、上記ばらつきが皆無であるという保証
は全くなく、通常はかなりのばらつきが存在する
のであるから妨害物質の影響が排除できても、上
記ばらつきに基づいて測定にかなりのばらつきが
生じてしまうという問題がある。
また、特開昭57−73667号公報、特開昭57−
211054号公報、特開昭57−74653公報に示される
構成を採用した場合には、膜構造が全体として一
体化された構造であるから、妨害物質に起因する
目詰りが生じた場合に、一体化された膜を全体と
して交換しなければならず、交換に伴なつて、妨
害物質の透過を阻止する膜のみならず固定化酵素
膜等も交換されることになり、膜構造全体として
交換に伴なう大幅な特性の変動を招いてしまう。
この結果、特性りの変動に起因して測定にかなり
のばらつきが生じてしまう。
＜発明の目的＞
この発明は上記の問題点に鑑みてなされたもの
であり、妨害物質の影響を排除するとともに、拡
散制限膜交換に伴なうばらつきの影響を大幅に抑
制することができる酵素電極を提供することを目
的としている。
＜問題点を解決するための手段＞
上記の目的を達成するための、この発明の酵素
電極は、測定対象物質を生理活性物質を固定した
固定化酵素膜で反応させ、その結果生成され、或
は消失される物質の量に対応する電気信号を出力
する酵素電極において、前記固定化酵素膜の表面
側に上記測定対象物質の拡散制限効果が高い第１
の拡散制限膜を固定してあるとともに、第１の拡
散制限膜の表面側に上記拡散制限効果が低い第２
の拡散制限膜を取外し可能に設けてあることを特
徴としている。
＜作用＞
以上の構成の酵素電極であれば、溶液に含まれ
る測定対象物質が、第１および第２の拡散制限膜
により制限された状態、即ち溶液中における濃度
に対応して定まる低い濃度の状態で固定化酵素膜
に導かれ、拡散制限膜を透過した測定対象物質濃
度に対応する電気信号を生成することができる。
そして、第２の拡散制限膜を交換した場合に
は、第２の拡散制限膜自体のばらつきおよび第２
の拡散制限膜の取付状態のばらつきが存在してい
るにも拘らず、第１および第２の拡散制限膜全体
としての制限効果をほぼ均一に保持し、妨害物質
の影響をも排除して正確に測定対象物質濃度を検
出することができる。
さらに詳細に説明すると、第１の拡散制限膜の
透過率（拡散係数を膜厚で除した値であり、制限
効果に逆比例する値）をP1、第２の拡散制限膜
の透過率をP2とすれば、両拡散制限膜全体とし
ての透過率Ｐは、Ｐ＝P1P2／（P1＋P2）とな
る。そして、P2＞＞P1であるから、P2の値に多
少ばらつきが存在してもＰは殆ど変化しないこと
になる。したがつて、妨害物質の影響を排除する
ために、第２の拡散制限膜を交換しても全体とし
ての制限効果をほぼ一定に保持することができ、
正確な濃度測定を行なうことができる。
＜実施例＞
以下、実施例を示す添付図面によつて詳細に説
明する。
第１図はこの発明の酵素電極の一実施例を示す
縦断面図であり、棒状体１の一面にPtからなる
中心電極２およびAgからなる対向電極３を有し
ているとともに、上記両電極を有している面を蔽
うように過酸化水素選択透過膜４、グルコースオ
キシダーゼ固定膜５および第１の拡散制限膜６を
積層し、キヤツプ７により固定している。そし
て、第１の拡散制限膜６に対して積層されるよう
に、ねじ込み式のキヤツプ９により第２の拡散制
限膜８を設けている。
尚、上記第１の拡散制限膜６として、二村化学
株式会社製プレインセロハン（番手＃300）使用
し、第２の拡散制限膜８としてニユークリポア社
製ポリカーボネート膜（孔径0.05μm、膜厚5μm）
を使用した。上記の構成の酵素電極によりグルコ
ース濃度の測定を行なつた結果、第２図Ａに示す
出力電流変化量−グルコース濃度特性を得ること
ができた。第２図Ｂはセロハンのみからなる拡散
制限膜を使用した酵素電極によりグルコース濃度
の測定を行なつた結果を示す出力電流変化量−グ
ルコース濃度特性であり、同一のグルコース濃度
に対する出力電流が上記実施例の場合と比較して
約２倍である。したがつて、上記実施例の方が、
測定可能な最大グルコース濃度を大きくすること
ができる。
また、上記実施例の構成の酵素電極を使用し、
かつ、第２の拡散制限膜８を毎回交換してグルコ
ース濃度が150mg／dlの溶液を測定した場合の出
力電流変化量を次表に示す。尚、比較例として拡
散制限膜を１枚のセロハンとし、かつ、セロハン
を毎回交換してグルコース濃度が150mg／dlの溶
液を測定した場合の出力電流変化をも示した。
<Industrial Application Field> This invention relates to an enzyme electrode, and more specifically, to an enzyme electrode in which the diffusion of a substance to be measured is restricted by a diffusion-limiting membrane, and the diffusion-restricted substance is guided to an immobilized enzyme membrane. Regarding electrodes. <Conventional technology> Focusing on the characteristic of being able to selectively detect extremely complex organic compounds, proteins, etc. with extremely high sensitivity, bioactive substances are immobilized on the surface of electrodes. Research and development is being carried out to measure the above-mentioned organic compounds, proteins, etc. using enzyme electrodes. When measuring a target substance using the enzyme electrode described above, the enzyme fixed on the surface of the electrode oxidizes or reduces the target substance, so the substance changes as a result of the oxidation or reduction. By measuring oxygen concentration, hydrogen peroxide concentration, etc., it is possible to indirectly know the concentration of the substance to be measured. Specifically, when measuring glucose concentration, it is sufficient to use glucose oxidase (GOD) as a physiologically active substance, and the following reaction takes place: glucose + O 2 + H 2 OGOD ---→ gluconic acid + H 2 O 2 Therefore, glucose concentration can be determined by detecting a decrease in dissolved oxygen concentration or an increase in hydrogen peroxide concentration. Furthermore, as is clear from the above reaction equation, the measurement limit of glucose concentration is determined based on the amount of oxygen in the solution to be measured, so it is possible to expand the measurement limit by limiting the amount of glucose that reaches glucose oxidase. was noticed,
As shown in Japanese Unexamined Patent Publication No. 59-22620, a glucose-limiting permeable membrane has been proposed. Although the above description has mainly been given to the case of measuring the glucose concentration, the same applies to the case of measuring the concentration of other organic polymers, proteins, etc. In addition, there is a thin-layer cell in which an intima layer, an enzyme layer, an electrically conductive layer, and an adventitia layer are laminated in this order (see JP-A-57-73667). are arranged symmetrically and an outer membrane is arranged on the outside of each inner membrane (see JP-A-57-73667); a first porous cell in which an enzyme is immobilized and a conductive thin film is formed; a second porous film formed with a conductive thin film for removing interfering substances, and an insulating porous film interposed between both porous films (Japanese Unexamined Patent Publication No. 57-211054) ), and a structure in which the first diaphragm and the second diaphragm are adhesively integrated by interposing a ring-shaped film, and a gel-like substance containing an enzyme is accommodated in the space formed by the ring-shaped film and both diaphragms. Laminated film (Unexamined Japanese Patent Publication No. 1983-
74653) has been proposed as a configuration capable of eliminating interfering substances such as polymer substances. <Problems to be Solved by the Invention> In the enzyme electrode disclosed in JP-A-59-22620, when the solution containing the substance to be measured also contains other interfering substances with large particle sizes, diffusion In addition to restricting the diffusion of the analyte, the restriction membrane can also prevent the permeation of interfering substances, making it possible to accurately measure the concentration of the analyte over a wide range. Also, JP-A-57-73667, JP-A-57-
Even when the configurations shown in JP-A No. 211054 and JP-A-57-74653 are adopted, a sufficient effect of blocking the passage of interfering substances and a certain degree of diffusion restriction effect of the substance to be measured can be achieved. Adopting the configuration shown in Japanese Patent Application Laid-open No. 59-22620,
If a single measurement operation is performed, a considerable amount of interfering substances will adhere to the diffusion-limiting membrane, making it impossible to perform subsequent measurements accurately. is 1
The diffusion-limiting membrane is replaced every time a measurement is performed, so that measurements can be performed without being affected by interfering substances. Therefore, if there are no variations in the characteristics of the diffusion limiting membrane itself to be replaced and variations in the mounting condition, the effects of interfering substances can be eliminated and accurate measurements can be performed. However, there is no guarantee that the above-mentioned variations will be completely eliminated; there is usually a considerable variation, so even if the influence of interfering substances can be eliminated, there will still be considerable variation in measurements based on the above-mentioned variations. There's a problem. Also, JP-A-57-73667, JP-A-57-
When the structure shown in Publication No. 211054 and Japanese Unexamined Patent Publication No. 57-74653 is adopted, the membrane structure is an integrated structure as a whole, so if clogging occurs due to interfering substances, The membrane must be replaced as a whole, and along with the replacement, not only the membrane that blocks the permeation of interfering substances but also the immobilized enzyme membrane, etc. must be replaced, and the entire membrane structure must be replaced. This results in significant changes in characteristics.
As a result, considerable variations in measurements occur due to variations in characteristics. <Purpose of the Invention> This invention was made in view of the above-mentioned problems, and provides an enzyme that can eliminate the influence of interfering substances and significantly suppress the influence of variations associated with diffusion-limiting membrane exchange. The purpose is to provide electrodes. <Means for Solving the Problems> In order to achieve the above object, the enzyme electrode of the present invention reacts a substance to be measured with an immobilized enzyme membrane on which a physiologically active substance is immobilized, and the resulting is an enzyme electrode that outputs an electric signal corresponding to the amount of the substance to be evaporated, and a first electrode that has a high diffusion restriction effect of the substance to be measured is placed on the surface side of the immobilized enzyme membrane.
A diffusion-limiting film is fixed thereon, and a second diffusion-limiting film having a low diffusion-limiting effect is fixed on the surface side of the first diffusion-limiting film.
The diffusion limiting membrane is removably provided. <Function> With the enzyme electrode configured as above, the substance to be measured contained in the solution is restricted by the first and second diffusion limiting membranes, that is, at a low concentration determined corresponding to the concentration in the solution. It is possible to generate an electrical signal corresponding to the concentration of the substance to be measured that has passed through the diffusion-limiting membrane. When the second diffusion-limiting membrane is replaced, variations in the second diffusion-limiting membrane itself and
Despite variations in the mounting conditions of the first and second diffusion limiting membranes, the limiting effect of the first and second diffusion limiting membranes as a whole is maintained almost uniformly, and the influence of interfering substances is also eliminated to ensure accuracy. The concentration of the substance to be measured can be detected. To explain in more detail, the transmittance of the first diffusion-limiting film (a value obtained by dividing the diffusion coefficient by the film thickness, which is inversely proportional to the restriction effect) is P1, and the transmittance of the second diffusion-limiting film is P2. Then, the transmittance P of both diffusion limiting films as a whole is P=P1P2/(P1+P2). Since P2>>P1, even if there is some variation in the value of P2, P will hardly change. Therefore, even if the second diffusion limiting membrane is replaced in order to eliminate the influence of interfering substances, the overall limiting effect can be kept approximately constant;
Accurate concentration measurements can be made. <Examples> Hereinafter, examples will be described in detail with reference to the accompanying drawings showing examples. FIG. 1 is a longitudinal sectional view showing an embodiment of the enzyme electrode of the present invention, which has a center electrode 2 made of Pt and a counter electrode 3 made of Ag on one surface of a rod-shaped body 1, and both of the electrodes A hydrogen peroxide selectively permeable membrane 4, a glucose oxidase fixing membrane 5, and a first diffusion limiting membrane 6 are laminated so as to cover the surface having the membrane, and are fixed by a cap 7. A second diffusion-limiting membrane 8 is provided with a screw-in cap 9 so as to be laminated on the first diffusion-limiting membrane 6. As the first diffusion-limiting membrane 6, plain cellophane (count #300) manufactured by Futamura Chemical Co., Ltd. was used, and as the second diffusion-limiting membrane 8, a polycarbonate membrane manufactured by Nucleipore (pore diameter 0.05 μm, film thickness 5 μm) was used.
It was used. As a result of measuring the glucose concentration using the enzyme electrode configured as described above, it was possible to obtain the output current variation vs. glucose concentration characteristic shown in FIG. 2A. Figure 2B shows the output current variation vs. glucose concentration characteristic showing the results of glucose concentration measurement using an enzyme electrode using a diffusion-limiting membrane made only of cellophane. This is approximately twice as large as in the example case. Therefore, the above embodiment is more
The maximum measurable glucose concentration can be increased. In addition, using the enzyme electrode configured as in the above example,
The following table shows the amount of change in output current when a solution with a glucose concentration of 150 mg/dl is measured by replacing the second diffusion limiting membrane 8 every time. As a comparative example, the change in output current is also shown when a diffusion-limiting membrane is made of one sheet of cellophane, and a solution with a glucose concentration of 150 mg/dl is measured by replacing the cellophane each time.
【表】
この結果、本実施例の場合には出力電流変化量
の平均値は122nA／ｓであり、比較例の200nA／
ｓより大幅に小さくなつているが、10回の測定を
通じてばらつきは1.6％であり、比較例のばらつ
き10.9％より大幅に小さくなつており、第２の拡
散制限膜８を交換することに伴なうばらつきを大
幅に抑制し、安定したグルコース濃度の測定を行
なわせることができた。
特に血液中のグルコース濃度の測定を行なう場
合には、通常１回の測定により、第２の拡散制限
膜８に大粒径の血球が付着し、目詰り状態になる
のであるから、毎回交換することが必要になる。
しかし、このような条件下においても、高い安定
性での測定を行なわせることができることにな
る。
尚、この発明は上記実施例に限定されるもので
はなく、例えば過酸化水素選択透過膜を固定化酵
素膜にキヤステイング形成し、第１の拡散制限膜
を水溶性接着剤等により接着することにより一体
化することが可能である他、両拡散制限膜による
制限効果をそれぞれ異ならせることが可能であ
り、その他この発明の要旨を変更しない範囲内に
おいて種々の設計変更を施すことが可能である。
＜発明の効果＞
以上のようにこの発明は、拡散制限膜を２層構
造とし、制限効果が小さい拡散制限膜のみを交換
可能としているので、拡散制限膜を交換しても全
体としての制限効果をほぼ一定に保持して、安定
した対象物質濃度の測定を行なうことができるの
みならず、拡散制限膜の交換に伴なう固定化酵素
膜の損傷を大幅に抑制することができ、さらに
は、交換可能な拡散制限膜を湿潤し易い厚みにす
ることができるので、交換用の拡散制限膜を乾燥
保存することができるという特有の効果を奏す
る。[Table] As a result, in the case of this example, the average value of the output current change is 122nA/s, and in the comparative example, it is 200nA/s.
However, the variation was 1.6% over the 10 measurements, which was significantly smaller than the 10.9% variation in the comparative example, and the variation was significantly smaller than that of the comparative example, which was caused by replacing the second diffusion-limiting film 8. We were able to significantly suppress the variation in glucose concentration and perform stable glucose concentration measurements. In particular, when measuring the glucose concentration in blood, large blood cells adhere to the second diffusion-limiting membrane 8 and it becomes clogged after one measurement, so it must be replaced every time. It becomes necessary.
However, even under such conditions, measurements can be performed with high stability. It should be noted that the present invention is not limited to the above-mentioned embodiments; for example, a hydrogen peroxide selectively permeable membrane may be casted onto an immobilized enzyme membrane, and the first diffusion-limiting membrane may be bonded with a water-soluble adhesive or the like. In addition to being able to integrate the two diffusion limiting films, it is also possible to make the limiting effects of both diffusion limiting films different, and it is also possible to make various other design changes within the scope of the gist of the present invention. . <Effects of the Invention> As described above, the present invention has a two-layer structure for the diffusion restriction membrane, and only the diffusion restriction membrane with a small restriction effect can be replaced, so even if the diffusion restriction membrane is replaced, the overall restriction effect is reduced. Not only can the concentration of the target substance be measured stably by keeping the concentration almost constant, but also damage to the immobilized enzyme membrane caused by replacing the diffusion-limiting membrane can be significantly suppressed. Since the replaceable diffusion-limiting membrane can be made to have a thickness that is easy to wet, a unique effect is achieved in that the replacement diffusion-limiting membrane can be stored in a dry state.
第１図はこの発明の酵素電極の一実施例を示す
縦断面図、第２図Ａは第１図の実施例による測定
データを示す図、第２図Ｂは比較例による測定デ
ータを示す図。
５…グルコースオキシダーゼ固定膜、６…第１
の拡散制限膜、８…第２の拡散制限膜。
FIG. 1 is a vertical cross-sectional view showing an embodiment of the enzyme electrode of the present invention, FIG. 2A is a diagram showing measurement data according to the embodiment of FIG. 1, and FIG. 2B is a diagram showing measurement data according to a comparative example. . 5... Glucose oxidase fixed membrane, 6... First
diffusion-limiting film, 8... second diffusion-limiting film.
Claims (1)
化酵素膜で反応させ、その結果生成され、或は消
失される物質の量に対応する電気信号を出力する
酵素電極において、前記固定化酵素膜の表面側に
上記測定対象物質の拡散制限効果が高い第１の拡
散制限膜を固定してあるとともに、第１の拡散制
限膜の表面側に上記拡散制限効果が低い第２の拡
散制限膜を取外し可能に設けてあることを特徴と
する酵素電極。 ２ 第２の拡散制限膜が、測定対象物質より粒径
が大きい物質の透過を阻止するものである上記特
許請求の範囲第１項記載の酵素電極。[Scope of Claims] 1. An enzyme electrode that reacts a substance to be measured with an immobilized enzyme membrane on which a physiologically active substance is immobilized, and outputs an electrical signal corresponding to the amount of the substance produced or eliminated as a result, A first diffusion-limiting membrane having a high diffusion-limiting effect on the substance to be measured is fixed on the surface side of the immobilized enzyme membrane, and a second diffusion-limiting membrane having a low diffusion-limiting effect on the surface side of the first diffusion-limiting membrane. An enzyme electrode characterized by having a removable diffusion-limiting membrane. 2. The enzyme electrode according to claim 1, wherein the second diffusion-limiting membrane blocks the permeation of a substance having a particle size larger than that of the substance to be measured.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62080431A JPS63243863A (en) | 1987-03-31 | 1987-03-31 | Enzyme electrode |
| US07/407,672 US4923586A (en) | 1987-03-31 | 1989-09-14 | Enzyme electrode unit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62080431A JPS63243863A (en) | 1987-03-31 | 1987-03-31 | Enzyme electrode |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63243863A JPS63243863A (en) | 1988-10-11 |
| JPH0515220B2 true JPH0515220B2 (en) | 1993-03-01 |
Family
ID=13718079
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62080431A Granted JPS63243863A (en) | 1987-03-31 | 1987-03-31 | Enzyme electrode |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63243863A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0752170B2 (en) * | 1988-05-27 | 1995-06-05 | ダイキン工業株式会社 | Diffusion limiting membrane holder storage container |
| JP2655727B2 (en) * | 1989-08-09 | 1997-09-24 | 日機装株式会社 | Enzyme sensor |
| JP5164656B2 (en) * | 2008-04-25 | 2013-03-21 | 株式会社船井電機新応用技術研究所 | Sensor and biosensor |
| JP5350531B2 (en) * | 2012-12-18 | 2013-11-27 | 株式会社船井電機新応用技術研究所 | Sensor |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5773667A (en) * | 1980-08-25 | 1982-05-08 | Yellow Springs Instr | Galactose oxydase enzyme electrode with peculiar substrate |
| JPS5774653A (en) * | 1980-10-29 | 1982-05-10 | Yokogawa Hokushin Electric Corp | Lamination film for enzyme electrode and manufacture thereof |
| JPS57211054A (en) * | 1981-06-19 | 1982-12-24 | Matsushita Electric Ind Co Ltd | Enzyme electrode |
-
1987
- 1987-03-31 JP JP62080431A patent/JPS63243863A/en active Granted
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5773667A (en) * | 1980-08-25 | 1982-05-08 | Yellow Springs Instr | Galactose oxydase enzyme electrode with peculiar substrate |
| JPS5774653A (en) * | 1980-10-29 | 1982-05-10 | Yokogawa Hokushin Electric Corp | Lamination film for enzyme electrode and manufacture thereof |
| JPS57211054A (en) * | 1981-06-19 | 1982-12-24 | Matsushita Electric Ind Co Ltd | Enzyme electrode |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63243863A (en) | 1988-10-11 |
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