JPS6332363A - Hydrogen peroxide electrode - Google Patents
Hydrogen peroxide electrodeInfo
- Publication number
- JPS6332363A JPS6332363A JP61175317A JP17531786A JPS6332363A JP S6332363 A JPS6332363 A JP S6332363A JP 61175317 A JP61175317 A JP 61175317A JP 17531786 A JP17531786 A JP 17531786A JP S6332363 A JPS6332363 A JP S6332363A
- Authority
- JP
- Japan
- Prior art keywords
- hydrogen peroxide
- electrode
- diaphragm
- liquid
- permeable membrane
- 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.)
- Pending
Links
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 title claims abstract description 141
- 239000012528 membrane Substances 0.000 claims abstract description 37
- 230000002209 hydrophobic effect Effects 0.000 claims abstract description 14
- 239000003792 electrolyte Substances 0.000 claims abstract description 11
- 239000007789 gas Substances 0.000 claims abstract description 9
- 239000011148 porous material Substances 0.000 claims description 10
- 229920001343 polytetrafluoroethylene Polymers 0.000 claims description 5
- 239000004810 polytetrafluoroethylene Substances 0.000 claims description 5
- 238000001514 detection method Methods 0.000 claims description 4
- -1 polytetrafluoroethylene Polymers 0.000 claims description 3
- 239000007788 liquid Substances 0.000 abstract description 38
- 108090000790 Enzymes Proteins 0.000 abstract description 12
- 102000004190 Enzymes Human genes 0.000 abstract description 12
- 108010093096 Immobilized Enzymes Proteins 0.000 abstract description 6
- 239000012466 permeate Substances 0.000 abstract description 4
- 238000012360 testing method Methods 0.000 description 18
- 239000000243 solution Substances 0.000 description 10
- 238000005259 measurement Methods 0.000 description 7
- 238000000034 method Methods 0.000 description 7
- 229910052760 oxygen Inorganic materials 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 239000008151 electrolyte solution Substances 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 4
- 239000000523 sample Substances 0.000 description 4
- 239000012085 test solution Substances 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 238000004061 bleaching Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000002452 interceptive effect Effects 0.000 description 3
- 235000014102 seafood Nutrition 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 239000000758 substrate Substances 0.000 description 3
- 239000002351 wastewater Substances 0.000 description 3
- CIWBSHSKHKDKBQ-JLAZNSOCSA-N Ascorbic acid Chemical compound OC[C@H](O)[C@H]1OC(=O)C(O)=C1O CIWBSHSKHKDKBQ-JLAZNSOCSA-N 0.000 description 2
- 102000016938 Catalase Human genes 0.000 description 2
- 108010053835 Catalase Proteins 0.000 description 2
- 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 2
- WCUXLLCKKVVCTQ-UHFFFAOYSA-M Potassium chloride Chemical compound [Cl-].[K+] WCUXLLCKKVVCTQ-UHFFFAOYSA-M 0.000 description 2
- 238000011088 calibration curve Methods 0.000 description 2
- HVYWMOMLDIMFJA-DPAQBDIFSA-N cholesterol Chemical compound C1C=C2C[C@@H](O)CC[C@]2(C)[C@@H]2[C@@H]1[C@@H]1CC[C@H]([C@H](C)CCCC(C)C)[C@@]1(C)CC2 HVYWMOMLDIMFJA-DPAQBDIFSA-N 0.000 description 2
- 239000008103 glucose Substances 0.000 description 2
- 239000010842 industrial wastewater Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229910000510 noble metal Inorganic materials 0.000 description 2
- 230000003204 osmotic effect Effects 0.000 description 2
- 229910052697 platinum Inorganic materials 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 229910052709 silver Inorganic materials 0.000 description 2
- 239000004332 silver Substances 0.000 description 2
- 229910001868 water Inorganic materials 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 1
- 102000004316 Oxidoreductases Human genes 0.000 description 1
- 108090000854 Oxidoreductases Proteins 0.000 description 1
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 1
- 229910021607 Silver chloride Inorganic materials 0.000 description 1
- 229960005070 ascorbic acid Drugs 0.000 description 1
- 235000010323 ascorbic acid Nutrition 0.000 description 1
- 239000011668 ascorbic acid Substances 0.000 description 1
- WQZGKKKJIJFFOK-VFUOTHLCSA-N beta-D-glucose Chemical compound OC[C@H]1O[C@@H](O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-VFUOTHLCSA-N 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 235000012000 cholesterol Nutrition 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 235000013305 food Nutrition 0.000 description 1
- 239000003349 gelling agent Substances 0.000 description 1
- 235000001727 glucose Nutrition 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 229920000058 polyacrylate Polymers 0.000 description 1
- 239000001103 potassium chloride Substances 0.000 description 1
- 235000011164 potassium chloride Nutrition 0.000 description 1
- 238000010926 purge Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000012488 sample solution Substances 0.000 description 1
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 description 1
- 239000003115 supporting electrolyte Substances 0.000 description 1
- BFKJFAAPBSQJPD-UHFFFAOYSA-N tetrafluoroethene Chemical group FC(F)=C(F)F BFKJFAAPBSQJPD-UHFFFAOYSA-N 0.000 description 1
- 235000012431 wafers Nutrition 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Measuring Or Testing Involving Enzymes Or Micro-Organisms (AREA)
Abstract
Description
産遠」Ｊ■ＵＷ飢訪
本発明は、過酸化水素電極に関し、更に詳述すると、工
業排水等の種々の被検液中の過酸化水素濃度を直接測定
するのに有効に使用されるほか、グルコースセンサ等の
酵素電極の下地電極としても使用し得るなど、種々の用
途に広範に利用することが可能な過酸化水素電極に関す
る。
来の 術 び 明が解決しようとする問題点過酸化水素
の測定は、工業工種々の分野で行なわれているが、電極
を用いる過酸化水素の測定は、大別して、いわゆる酵素
電極において固定化酵素膜の作用で生成した過酸化水素
を過酸化水素電極。
で検出する場合と、工業排水等の被検液中の過酸化水素
を電極を用いたセンサで測定する場合とがある。
前者の酵素電極は、臨床検査分野、食品検査分野等で実
用化が進んでいるもので、グルコース、アスコルビン酸
、コレステロール等の酸化酵素膜を下地電極゛である過
酸化水素電極の隔膜に張り合わせ、酸化酵素膜における
下記式（１）％式％（１）
（但し、Ｍは基質を示す。）
で示される反応によって生成する過酸化水素を下地電極
で検出することにより目的とする基質Ｍの濃度を求める
もので、現在過酸化水素電極はこの酵素電極の下地電極
として使用されることが最も多い。
また、後者の被検液中の過酸化水素濃度を過酸化水素セ
ンサで測定する場合としては、水産ねり製品の漂白に用
いた過酸化水素の製品中における残存量を測定する場合
、或いは半導体製造においてウェハーの洗浄に用いた過
酸化水素の排水中における残存量を廃液管理の目的で測
定する場合などが挙げられ、これらの目的のために実用
性の高い過酸化水素センサが要望されている。
従来、過酸化水素電極としては、過酸化水素が電気化学
的に活性であるため、例えば電解液として塩化カリウム
、アノードとして白金、カソードとして銀をそれぞれ使
用し、印加電圧をかけることにより、アノードでＨ２Ｏ
２→Ｏ，＋２Ｈ”＋ｅ↑なる反応、カソードで○、＋２
Ｈ２０＋２ｅ→４０Ｈ↑なる反応をそれぞれ生じさせ、
この時両極間に流れる過酸化水素量に比例した電流を検
出するようにしたものや、特願昭５７−１３６００１号
明細書に示されたように、例えば内部液としてアルカリ
液、アノードとして貴金属、カソードとして塩化銀をそ
れぞれ使用し、印加電圧をかけないでガルバニックに電
Ｍ電流を検出するようにしたもの等が用いられている。
この場合、過酸化水素電極の隔膜としては、親水性の透
過膜を用いるのが従来−殻内であった。
その理由としては、低濃度の過酸化水素は揮発性がない
とされており、このため隔膜として親水性の透過膜を用
いなければ過酸化水素が隔膜を透過して検知極表面に到
達せず、測定が不可能になることが挙げられる。また、
酵素電極においては、固定化酵素膜を調製する場合、酵
素を固定すべき膜の一部分に酵素を固定化し、この部分
を酵素膜として用いると共に、他の部分を隔膜として用
いることが多いが、グルコース等の基質との関係で固定
化酵素膜は親水性であることが必要であり、従って隔膜
も親水性になる。
しかし、上述したように過酸化水素電極の隔膜として親
水性の透過膜を用いた場合、内部液は親水性透過膜を透
過するので、この腹によっては内部液を隔膜として完全
に仕切゛ることかできず、内部液が隔膜を通って外部に
流出する。このため、従来より過酸化水素電極を使用す
るに際しては、サンプルを希釈するベース液の組成を内
部液である電解液の組成と同様にし、このベース液を隔
膜を通して電極内に浸透させることにより、いわば支持
電解液を外部から補給する方法が採用され、これによっ
て内部液の流出をカバーしているが、従来の過酸化水素
電極を使用する場合、このような方法を採っているため
■サンプル液が電極内に侵入し、サンプル液中の酸化還
元物質が容易に検知極表面に達するため、妨害成分が多
くなり、精密な測定を行なうことができない、■測定可
能なケースがサンプルをベース液で希釈する場合に限定
され、例えば過酸化水素電極を排水中に直接浸漬して測
定するなどの広範な用途に用いることができない、とい
った問題が生じるものであった。
一方、排水等の被検液中の過酸化水素濃度を直接測定し
得る過酸化水素センサとして、隔膜式のｗ１素電極に過
酸化水素を分解して酸素を発生するカタラーゼの固定化
酵素膜、或いはカタラーゼと類似機能を有する物質膜を
取り付け、過酸化水素の分解に伴う酸素量を測定するよ
うにしたものが公知である。しかし、このセンサは予め
酸素電極のセル内の酸素濃度を窒素ガスパージ等によっ
て下げておく必要があり、このため用途が限定されるも
のであった。
本発明は、上記事情に鑑みなされたもので、内部液が電
極外部に流出することがないと共に、被検液が電極内部
に侵入することがなく、従って排水に直接浸漬してその
過酸化水素濃度を測定するなどの広範な用途に使用し得
る上、妨害成分が少なく、正確な測定を行なうことが可
能な過酸化水素電極を提供することを目的とする。
朋」ｈThe present invention relates to a hydrogen peroxide electrode, and more specifically, it can be effectively used to directly measure the concentration of hydrogen peroxide in various test liquids such as industrial wastewater. The present invention relates to a hydrogen peroxide electrode that can be used in a wide variety of applications, such as being used as a base electrode for enzyme electrodes such as glucose sensors. Problems to be Solved by the Next Technique Measuring hydrogen peroxide is carried out in various fields of industry and engineering, but the measurement of hydrogen peroxide using electrodes can be roughly divided into two types: immobilized hydrogen peroxide using so-called enzyme electrodes. The hydrogen peroxide electrode generates hydrogen peroxide through the action of an enzyme membrane. In some cases, hydrogen peroxide in a test liquid such as industrial wastewater is measured with a sensor using an electrode. The former enzyme electrode is being put into practical use in the clinical testing field, food testing field, etc., and is made by pasting a membrane of an oxidizing enzyme such as glucose, ascorbic acid, or cholesterol onto a diaphragm of a hydrogen peroxide electrode, which is the base electrode. The target concentration of substrate M can be determined by detecting hydrogen peroxide produced by the reaction shown by the following formula (1)% formula (1) (where M indicates the substrate) using the base electrode in the oxidase membrane. Currently, hydrogen peroxide electrodes are most often used as the base electrode for this enzyme electrode. The latter method of measuring the hydrogen peroxide concentration in the test liquid using a hydrogen peroxide sensor is when measuring the residual amount of hydrogen peroxide used in the bleaching of seafood paste products, or when measuring the residual amount of hydrogen peroxide in a product used for bleaching seafood paste products, or when measuring the residual amount of hydrogen peroxide in a product used for bleaching seafood paste products, For example, the amount of hydrogen peroxide remaining in waste water used for cleaning wafers is measured for the purpose of waste liquid management, and a highly practical hydrogen peroxide sensor is desired for these purposes. Conventionally, since hydrogen peroxide is electrochemically active, hydrogen peroxide electrodes have been made using, for example, potassium chloride as the electrolyte, platinum as the anode, and silver as the cathode, and by applying an applied voltage to the anode. H2O
2→O, +2H”+e↑ reaction, ○, +2 at the cathode
The reaction H20+2e→40H↑ is generated,
At this time, a current proportional to the amount of hydrogen peroxide flowing between the two electrodes is detected, and as shown in Japanese Patent Application No. 57-136001, for example, an alkaline liquid is used as the internal liquid, a noble metal is used as the anode, etc. A device is used in which silver chloride is used as a cathode, and the electromagnetic current is detected galvanically without applying an applied voltage. In this case, a hydrophilic permeable membrane has conventionally been used as the diaphragm of the hydrogen peroxide electrode. The reason for this is that low concentrations of hydrogen peroxide are said to be nonvolatile, so unless a hydrophilic permeable membrane is used as a diaphragm, hydrogen peroxide will not pass through the diaphragm and reach the sensing electrode surface. , measurement becomes impossible. Also,
In enzyme electrodes, when preparing an immobilized enzyme membrane, the enzyme is often immobilized on a part of the membrane to which the enzyme is to be immobilized, and this part is used as the enzyme membrane, while the other part is used as a diaphragm. The immobilized enzyme membrane needs to be hydrophilic in relation to the substrate, and therefore the diaphragm is also hydrophilic. However, as mentioned above, when a hydrophilic permeable membrane is used as the diaphragm of the hydrogen peroxide electrode, the internal liquid passes through the hydrophilic permeable membrane, so depending on this gap, the internal liquid cannot be completely partitioned off as a diaphragm. The internal fluid leaks out through the diaphragm. For this reason, conventionally when using a hydrogen peroxide electrode, the composition of the base liquid for diluting the sample is made the same as the composition of the internal electrolyte solution, and this base liquid is permeated into the electrode through the diaphragm. In other words, a method of replenishing the supporting electrolyte from the outside is adopted, which covers the leakage of the internal solution. However, when using conventional hydrogen peroxide electrodes, this method is used, so ■ Sample liquid enters the electrode, and redox substances in the sample solution easily reach the detection electrode surface, resulting in a large number of interfering components and making it impossible to perform accurate measurements. This method is limited to cases where it is diluted, and there is a problem in that it cannot be used in a wide range of applications, such as measurements made by directly immersing a hydrogen peroxide electrode in waste water. On the other hand, as a hydrogen peroxide sensor that can directly measure the concentration of hydrogen peroxide in a sample liquid such as wastewater, a diaphragm-type W1 element electrode is equipped with an immobilized enzyme membrane of catalase that decomposes hydrogen peroxide to generate oxygen. Alternatively, a device is known in which a membrane of a substance having a similar function to catalase is attached and the amount of oxygen accompanying the decomposition of hydrogen peroxide is measured. However, this sensor requires that the oxygen concentration in the cell of the oxygen electrode be lowered in advance by nitrogen gas purge or the like, which limits its use. The present invention has been made in view of the above circumstances, and the internal liquid does not flow out of the electrode, and the test liquid does not enter the electrode. It is an object of the present invention to provide a hydrogen peroxide electrode that can be used in a wide range of applications such as measuring concentration, has few interfering components, and can perform accurate measurements. ``h''
【灸邂】「シゑＬ１慕榎り曵」ＪＬ作囲一本発明
は、上記目的を達成するため、電極本体の検出端に隔膜
を配設し、かつこの電極本体内に電解液を封入すると共
に、この電解液にアノード及びカソードを浸漬してなり
、過酸化水素の作用で上記アノードとカソードとの間に
生じる電流を検出するようにした過酸化水素電極におい
て、上記隔膜として疎水性のガス透過膜を用いたもので
ある。
即ち、本発明者は、過酸化水素電極の隔膜について種々
研究を行なっているうち、例えば多孔性ポリテトラフル
オロエチレン膜のような疎水性のガス透過膜を、わずか
ではあるが過酸化水素が透過し、従ってこの疎水性のガ
ス透過膜を隔膜として用いることにより、内部液が隔膜
を通って外部に流出したり、被検液が隔膜を通って電極
内に侵入することのない電極が得られることを知見し、
本発明をなすに至ったもので、本発明電極においては、
過酸化水素が隔膜として配設された疎水性のガス透過膜
を透過し、この過酸化水素の作用でアノードとカソード
との間に生じる電流を検出することにより、過酸化水素
濃度が測定されるものである。
この場合、本発明において、アノード、カソード及び電
解液の種類に限定はなく、公知のものを適宜選択し、組
合せて使用することができる。
また、隔膜として用いる疎水性ガス透過膜の種類にも制
限はなく、過酸化水素電極の使用目的等に応じて種々の
ものを使用し得るが、平均孔径０．１〜１０μ程度の多
孔性ポリテトラフルオロエチレン膜を用いることが好ま
しい。この場合、隔膜の平均孔径を選択することにより
、電極の感度を適宜調整することができる。
なお、隔膜として用いた疎水性ガス透過膜の平均孔径に
よっては、内部液と被検液との間のイオン種、物質種の
濃度差に基づく浸透圧のバランス等により、内部液が隔
膜を通って外部に流出し、電解電流出力が不安定になっ
たり、内部液を頻繁に交換しなければならなくなるおそ
れが生じる。
このため、本発明においては内部液である電解質をゲル
化し、内部液と被検液との間に浸透圧が生じるのを防ぐ
ことが好ましく、これにより上述した内部液の流出を確
実に防止することができる。
この場合、ゲル化剤としては、ポリアクリル酸塩系の吸
水性樹脂等を用いることが好ましい。
次に実施例を示し、本発明を具体的に説明するが、本発
明は下記実施例に限定されるものではない。
去】Ｕ九
第１図は本発明の一実施例に係る過酸化水素電極を示す
もので、図中１は円筒状電極本体、２はこの本体１の底
部を閉塞する多孔性ポリテトラフルオロエチレン膜（住
友電工社製フロロポア）からなる隔膜である。上記本体
１内には水酸化カリウム溶液や水酸化ナトリウム溶液等
をゲル化したゲル化アルカリ性電解液３が入っており、
このゲル化アルカリ性電解液３中に例えば白金、金等の
貴金属で構成されるアノード（本実施例においては極径
４φ）４及び銀等で構成されるカソード５が浸漬されて
いる。
上記電極は、その検出端を過酸化水素を含む被検液中に
浸漬した場合、被検液中の過酸化水素が隔ｒｓ２を透過
し、アノード４及びカソード５に接触して両極間に電流
が流れる。従って、この電流を検出することにより、被
検液中の過酸化水素濃度を測定できるものである。また
、酵素電極の下地電極として用いる場合は、隔膜５に固
定化酵素膜を取り付けることにより、上記と同様に固定
化酵素膜の作用で生成した過酸化水素を検出し得る。
この場合、上記電極においては、隔膜２として疎水性ガ
ス透過膜を使用し、かつ内部液としてゲル化電解液を用
いたので、内部液の電極外への流出及び被検液の電極内
への流入が確実に防止される。従って、この電極によれ
ば、種々の被検液中の過酸化水素濃度を妨害成分の影響
を受けることなく直接正確に測定できるものである。
なお、上記実施例においては、内部液としてアルカリ電
解液を用い、ガルバニックな電解電流を検出するように
したが、これに限られず、電解質に塩化カリウム等の中
性塩を使用し、印加電圧をかけてポーラログラフイック
な電解電流を検出する方法を採用しても差支えない。
次に実験例を示す。
ヌ」ｕ」１
第１図に示す電極において、隔膜として平均孔径が０．
１μ、０．２μ及び１．２μの多孔性ＰＴＦＥ膜をそれ
ぞれ使用し、被検液中の過酸化水素濃度に対する電極出
力の変化を調べた。結果を第２図に示す。なお、図中ａ
は平均孔径０．１μ、ｂは０．２μ、Ｃは１．２μの透
過膜を用いた結果を示す。
第２図の結果より、隔膜の孔径が大きくなるとともに電
極の出力電流は大きくなることが認められる。これは、
孔径によってＨ，Ｏ，の透過速度が異なり、孔径を選釈
することによって電極感度を適宜調整し得ることを示す
。
実験例２
隔膜として平均孔径０．１μの多孔性ＰＴＦＥ膜を用い
た第１図に示す電極を使用し、被検液中の過酸化水素濃
度を測定した。第３図に検量線を示す。
第３図の結果より、本発明電極によれば過酸化水素濃度
を正確に測定し得ることが認められる。
ヌ」ｕ」灸
過酸化水素濃度が一定で、ｐＨやイオン強度が異なる種
々の被検液に対する電解電流出力の様子を第１図に示す
装置を用いて調べた。結果を第４図に示す。
第４図の結果より、電解液をゲル化した第１図の電極は
、被検液の性状にかかわりなく安定な出力を得られるこ
とが認められる。
只」Ｌγ筬逮−
以上説明したように、本発明の過酸化水素電極は隔膜を
疎水性ガス透過膜により形成したので。
この隔膜を過酸化水素が透過し、従って過酸化水素濃度
を良好に測定し得る。また、内部液が隔膜を通って電極
外に流出したり、被検液が隔膜を通って電極内に流入す
ることが可及的に防止されるので、親水性の隔膜を用い
た従来の過酸化水素電極と異なり、サンプルを希釈する
ベース液によって内部液を補充する必要がなく、このた
め種々の被検液に直接浸漬して過酸化水素を測定、し得
る上、被検液中の妨害成分の影響を受けにくいため、正
確な測定が行なわれる。従って、本発明電極は用途、使
用方法等に制限が少なく、広範囲に使用され、実用的価
値が大きいものである。[Moxibustion] "Shie L1 Minoki Rikan" JL Sakueiichi In order to achieve the above object, the present invention provides a diaphragm at the detection end of the electrode body, and seals an electrolyte in the electrode body. At the same time, in a hydrogen peroxide electrode which is made by immersing an anode and a cathode in this electrolytic solution and detects the current generated between the anode and cathode due to the action of hydrogen peroxide, a hydrophobic membrane is used as the diaphragm. It uses a gas permeable membrane. That is, while conducting various studies on the diaphragm of hydrogen peroxide electrodes, the present inventor discovered that hydrogen peroxide permeates through a hydrophobic gas-permeable membrane such as a porous polytetrafluoroethylene membrane, albeit in a small amount. Therefore, by using this hydrophobic gas-permeable membrane as a diaphragm, an electrode can be obtained in which the internal liquid does not leak out through the diaphragm and the test liquid does not enter the electrode through the diaphragm. I found out that
The present invention has been achieved, and in the electrode of the present invention,
Hydrogen peroxide permeates through a hydrophobic gas-permeable membrane arranged as a diaphragm, and the hydrogen peroxide concentration is measured by detecting the current generated between the anode and cathode due to the action of hydrogen peroxide. It is something. In this case, in the present invention, the types of anode, cathode, and electrolyte are not limited, and known ones can be appropriately selected and used in combination. There is also no limit to the type of hydrophobic gas permeable membrane used as the diaphragm, and various types can be used depending on the purpose of use of the hydrogen peroxide electrode. Preferably, a tetrafluoroethylene membrane is used. In this case, the sensitivity of the electrode can be adjusted as appropriate by selecting the average pore diameter of the diaphragm. Note that depending on the average pore diameter of the hydrophobic gas permeable membrane used as a diaphragm, the internal liquid may pass through the diaphragm due to the balance of osmotic pressure based on the concentration difference of ionic species and substance species between the internal liquid and the test liquid. This may cause the electrolytic current output to become unstable or the internal liquid to need to be replaced frequently. Therefore, in the present invention, it is preferable to gel the electrolyte, which is the internal solution, to prevent the generation of osmotic pressure between the internal solution and the test solution, thereby reliably preventing the above-mentioned outflow of the internal solution. be able to. In this case, it is preferable to use a polyacrylate-based water-absorbing resin or the like as the gelling agent. EXAMPLES Next, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to the following Examples. Figure 1 shows a hydrogen peroxide electrode according to an embodiment of the present invention, in which 1 is a cylindrical electrode body, and 2 is a porous polytetrafluoroethylene that closes the bottom of the body 1. It is a diaphragm made of a membrane (Fluoropore manufactured by Sumitomo Electric). The main body 1 contains a gelled alkaline electrolyte 3 made by gelling a potassium hydroxide solution, a sodium hydroxide solution, etc.
In this gelled alkaline electrolytic solution 3, an anode (pole diameter 4φ in this embodiment) 4 made of a noble metal such as platinum or gold, and a cathode 5 made of silver or the like are immersed. When the detection end of the electrode is immersed in a test liquid containing hydrogen peroxide, the hydrogen peroxide in the test liquid passes through the gap rs2, contacts the anode 4 and the cathode 5, and creates a current between the two electrodes. flows. Therefore, by detecting this current, the hydrogen peroxide concentration in the test liquid can be measured. Furthermore, when used as a base electrode for an enzyme electrode, by attaching an immobilized enzyme membrane to the diaphragm 5, hydrogen peroxide generated by the action of the immobilized enzyme membrane can be detected in the same manner as described above. In this case, in the above electrode, a hydrophobic gas-permeable membrane was used as the diaphragm 2, and a gelled electrolyte was used as the internal solution, so that the internal solution did not flow out of the electrode and the test solution did not enter the electrode. Inflow is reliably prevented. Therefore, with this electrode, the hydrogen peroxide concentration in various test liquids can be directly and accurately measured without being affected by interfering components. In the above embodiment, an alkaline electrolyte was used as the internal solution to detect the galvanic electrolytic current. There is no problem in adopting a method of detecting polarographic electrolytic current. Next, an experimental example will be shown. NU'U'1 In the electrode shown in FIG. 1, the diaphragm has an average pore diameter of 0.
Porous PTFE membranes of 1μ, 0.2μ, and 1.2μ were used to examine changes in electrode output with respect to hydrogen peroxide concentration in the test liquid. The results are shown in Figure 2. In addition, a in the figure
shows the results using a permeable membrane with an average pore diameter of 0.1μ, b of 0.2μ, and C of 1.2μ. From the results shown in FIG. 2, it is recognized that as the pore diameter of the diaphragm increases, the output current of the electrode increases. this is,
This shows that the permeation rate of H and O varies depending on the pore size, and that electrode sensitivity can be adjusted appropriately by selecting the pore size. Experimental Example 2 The hydrogen peroxide concentration in the test liquid was measured using the electrode shown in FIG. 1 using a porous PTFE membrane with an average pore diameter of 0.1 μm as a diaphragm. Figure 3 shows the calibration curve. From the results shown in FIG. 3, it is recognized that hydrogen peroxide concentration can be accurately measured using the electrode of the present invention. Using the apparatus shown in FIG. 1, the electrolytic current output for various test liquids with a constant hydrogen peroxide concentration and different pH and ionic strength was investigated. The results are shown in Figure 4. From the results shown in FIG. 4, it is recognized that the electrode shown in FIG. 1, in which the electrolytic solution is gelled, can obtain a stable output regardless of the properties of the test liquid. As explained above, in the hydrogen peroxide electrode of the present invention, the diaphragm is formed of a hydrophobic gas permeable membrane. Hydrogen peroxide permeates through this diaphragm, thus allowing good measurement of hydrogen peroxide concentration. In addition, it is possible to prevent the internal liquid from flowing out of the electrode through the diaphragm and the test liquid from flowing into the electrode through the diaphragm, which is different from the conventional method using a hydrophilic diaphragm. Unlike hydrogen oxide electrodes, there is no need to replenish the internal solution with a base solution to dilute the sample, and therefore hydrogen peroxide can be measured by directly immersing it in various test solutions, and there is no interference in the test solution. Accurate measurements are made because it is not easily affected by components. Therefore, the electrode of the present invention has few restrictions on its application, method of use, etc., can be used widely, and has great practical value.
第１図は本発明の一実施例に係る過酸化水素電極を示す
一部省略断面図、第２図は第１図の電極における平均孔
径と電極出力との関係を示すグラフ、第３図は第１図の
電極による検量線の一例を示すグラフ、第４図は第１図
の電極により過酸化水素濃度が一定で種々のｐＨ、イオ
ン強度を有する被検液を測定した場合の電極出力を示す
グラフである。
１・・・電極本体、２・・・隔膜（疎水性ガス透過膜）
、３・・・内部液、４・・・アノード、５・・・カソー
ド。
出願人 電気化学計器 株式会社
代理人 弁理士 小 島 隆 同
第１図
第２図
３帽昧＊、）ＬＬ （ＰＦ−）FIG. 1 is a partially omitted sectional view showing a hydrogen peroxide electrode according to an embodiment of the present invention, FIG. 2 is a graph showing the relationship between the average pore diameter and electrode output in the electrode of FIG. 1, and FIG. A graph showing an example of a calibration curve using the electrode in Figure 1. Figure 4 shows the electrode output when measuring test liquids with a constant hydrogen peroxide concentration and various pH and ionic strengths using the electrode in Figure 1. This is a graph showing. 1... Electrode body, 2... Diaphragm (hydrophobic gas permeable membrane)
, 3... Internal liquid, 4... Anode, 5... Cathode. Applicant Electrochemical Instrument Co., Ltd. Agent Patent Attorney Takashi Kojima Figure 1, Figure 2, Figure 3 *, ) LL (PF-)
Claims (1)
体内に電解液を封入すると共に、この電解液にアノード
及びカソードを浸漬してなり、過酸化水素の作用で上記
アノードとカソードとの間に生じる電流を検出するよう
にした過酸化水素電極において、上記隔膜として疎水性
のガス透過膜を用いたことを特徴とする過酸化水素電極
。 ２、疎水性のガス透過膜が平均孔径０．１〜１０μの多
孔性ポリテトラフルオロエチレン膜である特許請求の範
囲第１項記載の過酸化水素電極。 ３、電解液をゲル化してなる特許請求の範囲第１項又は
第２項記載の過酸化水素電極。[Claims] 1. A diaphragm is provided at the detection end of the electrode body, an electrolyte is sealed in the electrode body, and an anode and a cathode are immersed in this electrolyte. A hydrogen peroxide electrode configured to detect a current generated between the anode and the cathode as a result of the action, characterized in that a hydrophobic gas-permeable membrane is used as the diaphragm. 2. The hydrogen peroxide electrode according to claim 1, wherein the hydrophobic gas permeable membrane is a porous polytetrafluoroethylene membrane with an average pore diameter of 0.1 to 10 μm. 3. The hydrogen peroxide electrode according to claim 1 or 2, which is formed by gelling an electrolyte.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61175317A JPS6332363A (en) | 1986-07-25 | 1986-07-25 | Hydrogen peroxide electrode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61175317A JPS6332363A (en) | 1986-07-25 | 1986-07-25 | Hydrogen peroxide electrode |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6332363A true JPS6332363A (en) | 1988-02-12 |
Family
ID=15993976
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61175317A Pending JPS6332363A (en) | 1986-07-25 | 1986-07-25 | Hydrogen peroxide electrode |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6332363A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08304331A (en) * | 1995-04-26 | 1996-11-22 | Prominent Dosiertechnik Gmbh | Electrochemical measuring cell |
| JP2009069025A (en) * | 2007-09-13 | 2009-04-02 | Dkk Toa Corp | Diaphragm type hydrogen peroxide electrode |
| JP2017000970A (en) * | 2015-06-11 | 2017-01-05 | 野村マイクロ・サイエンス株式会社 | Ultrapure water production system, and ultrapure water production method |
-
1986
- 1986-07-25 JP JP61175317A patent/JPS6332363A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08304331A (en) * | 1995-04-26 | 1996-11-22 | Prominent Dosiertechnik Gmbh | Electrochemical measuring cell |
| JP2009069025A (en) * | 2007-09-13 | 2009-04-02 | Dkk Toa Corp | Diaphragm type hydrogen peroxide electrode |
| JP2017000970A (en) * | 2015-06-11 | 2017-01-05 | 野村マイクロ・サイエンス株式会社 | Ultrapure water production system, and ultrapure water production method |
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