JPH0663999B2 - Biomass measurement electrode - Google Patents
Biomass measurement electrodeInfo
- Publication number
- JPH0663999B2 JPH0663999B2 JP63293671A JP29367188A JPH0663999B2 JP H0663999 B2 JPH0663999 B2 JP H0663999B2 JP 63293671 A JP63293671 A JP 63293671A JP 29367188 A JP29367188 A JP 29367188A JP H0663999 B2 JPH0663999 B2 JP H0663999B2
- Authority
- JP
- Japan
- Prior art keywords
- electrode
- measuring
- electrodes
- base material
- biomass
- 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.)
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- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は、培養装置、バリオリアクタ、処理装置内の生
物量をオンラインで計測するための電極に関するもので
ある。したがって本発明は、バイオインダストリをはじ
め、医療、食品工業、下水・排水処理といった分野にお
いて非常に重要な役割を果すものである。TECHNICAL FIELD The present invention relates to an electrode for on-line measurement of a biomass in a culture device, a vario reactor, and a treatment device. Therefore, the present invention plays a very important role in fields such as bioindustry, medical treatment, food industry, and sewage / wastewater treatment.
（従来の技術） 各種微生物、動物細胞、植物細胞等を用いて有用物質を
生産するバイオリアクタや培養装置は、その内部の生物
量が時々刻々変化するものであり、バイオリアクタ、培
養装置の制御を行ったり、内部状態を知る上で生物量を
測定することが非常に重要である。(Prior Art) Bioreactors and culturing devices that produce useful substances using various microorganisms, animal cells, plant cells, etc., control the bioreactor and culturing devices because the amount of living organisms inside them changes moment by moment. It is very important to measure the amount of living organisms in order to carry out or to know the internal condition.
バイオリアクタ等において、細胞の大きさが小さい各種
微生物においては、懸濁溶液中の菌体濃度の測定では、
培地中での微生物の各種光学的性質に基づいて、微生物
濃度を測定することが一応は可能である。しかし、光を
使用した各種測定法では生物以外のSSの混在による生物
量の誤認、測定溶液の色や気泡による誤差の増大、測定
機構の複雑さ等の問題点がある。この様な場合には、現
在のところリアクタや培養装置から細胞をサンプリング
法により採取しなければならず、培養系への雑菌汚染の
危険性が大きく、雑菌汚染のため高価な培養液を廃棄し
なければならないことが多く、培養効率の向上が望まれ
ていたのである。また生物量等の情報をリアクタや培養
装置のオンライン制御等に反映することは不可能であ
り、生物をサンプリングすることなく、オンラインで生
物量を測定できる方法の開発が重要視されてきたのであ
る。In bioreactors, etc., for various microorganisms with small cell size, in measuring the bacterial cell concentration in the suspension solution,
It is possible to measure the concentration of microorganisms based on various optical properties of the microorganisms in the medium. However, various measuring methods using light have problems such as erroneous recognition of biomass due to the mixing of SS other than living organisms, increase in error due to color and bubbles of the measuring solution, and complexity of measuring mechanism. In such a case, at present, cells have to be collected from the reactor or the culture device by a sampling method, and there is a high risk of contamination of various bacteria in the culture system. In many cases, it was necessary to improve the culture efficiency. In addition, it is impossible to reflect information such as biomass on online control of reactors and culture devices, and it has been emphasized to develop a method that can measure biomass online without sampling organisms. .
最近、本発明者らにより培養装置内に金属電極を装着し
電気伝導度（導電率）および／又は電気容量（誘電率）
を測定することにより生物量をオンライン・リアルタイ
ムに計測する方法が発明された。Recently, the inventors of the present invention installed a metal electrode in a culture device to conduct electric conductivity (conductivity) and / or electric capacity (dielectric constant).
The method of measuring the amount of biomass online and in real time by measuring
本発明は、上記計測法により電気容量および／又は電気
伝導度の測定を可能とする生物量計測用電極に関するも
のであり、このような電極は従来知られておらず、新規
である。The present invention relates to an electrode for measuring a biological amount, which enables measurement of an electric capacity and / or an electric conductivity by the above-mentioned measuring method, and such an electrode has not hitherto been known and is novel.
（発明が解決しようとする問題点） 上記したように、従来の技術では、サンプリングするこ
となく、培養中の微生物量、動物および植物細胞といっ
た生物量を測定することは、全く不可能であった。(Problems to be Solved by the Invention) As described above, with the conventional technique, it was completely impossible to measure the amount of microorganisms in culture, the amount of organisms such as animal and plant cells without sampling. .
（問題点を解決するための手段） 本発明は、上記の技術の現状に鑑みてなされたものであ
って、培養槽中に少なくとも一対の金属電極を挿入し電
極が形成する電界中の電気容量および／又は電気伝導度
を測定することにより生物量のオンライン計測を可能と
するものである。(Means for Solving Problems) The present invention has been made in view of the current state of the art described above, in which at least a pair of metal electrodes are inserted into a culture tank to form an electric capacity in an electric field formed by the electrodes. And / or by measuring the electric conductivity, it is possible to perform online measurement of the biomass.
生物細胞は大雑把にいえば細胞核等を含む細胞質とそれ
を取り囲む細胞膜、壁から構成されている。このうち細
胞膜は脂質が主体となって構成されており非常に電気抵
抗値が高い。従って細胞を電界中におくと、細胞質に含
まれたイオンが移動することにより分極現象を示す。し
たがって細胞は一種のコンデンサとみなせる。一方細胞
を取り囲む培養液中には種々のイオンが含まれており細
胞を含む培養液は抵抗とコンデンサが並列に接続した等
価回路で示すことができる。したがってこのコンデンサ
部にあたる電気容量値を測定することにより細胞量の測
定が可能となる。なお細胞内のイオンが分極することに
よる影響はほぼ10MHz以下であった。A biological cell is roughly composed of a cytoplasm including a cell nucleus, a cell membrane surrounding the cytoplasm, and a wall. Of these, the cell membrane is mainly composed of lipids and has a very high electric resistance value. Therefore, when the cells are placed in an electric field, the ions contained in the cytoplasm move to exhibit a polarization phenomenon. Therefore, the cell can be regarded as a kind of capacitor. On the other hand, the culture solution surrounding the cells contains various ions, and the culture solution containing the cells can be represented by an equivalent circuit in which a resistor and a capacitor are connected in parallel. Therefore, the cell amount can be measured by measuring the electric capacitance value corresponding to the capacitor section. The effect of polarization of intracellular ions was about 10 MHz or less.
そこで、金属電極を装着し、電気容量、電気伝導度とい
った電気量を計測することにより各種生物量をサンプリ
ングすることなく、オンライン・リアルタイムで測定で
きる計測用電極を開発するため、各方面から検討の結
果、ここに遂に外界からのノイズ等の影響も受けること
なく正確に且つ容易に生物量を計測しうる電極の開発に
成功したものである。Therefore, in order to develop a measurement electrode that can be measured online and in real time without mounting various metal species by sampling the amount of electricity such as electric capacity and electric conductivity by mounting a metal electrode As a result, we have finally succeeded in developing an electrode that can accurately and easily measure the amount of living organisms without being affected by external noise and the like.
以下、本発明に係る生物量計測用電極について、図示し
た実施例を参照しながら詳述する。Hereinafter, the biological amount measuring electrode according to the present invention will be described in detail with reference to the illustrated embodiments.
先ずはじめに、本発明に係る生物量計測用電極に装着す
る金属電極について検討した。第１図に、電解液（20mM
-CaCl２溶液）中に一対の電極（電極面積1cm２、電極間
距離40mm）を挿入して電気容量の周数特性を測定した一
例を示す。ここで低周波側にいくにつれ電気容量が急激
に大きくなるがこれは電極分極の影響である。この電極
分極の影響はイオン濃度が高くなるにつれ高周波側にシ
フトしていくことが知られている。本発明において種々
の金属について電極分極の周波数特性を測定した結果を
第１図に示す。第１図において、１は白金黒電極、２は
白金電極、３はステンレス電極、４はアルミニウム電
極、５は銅電極での測定結果である。これから、溶液中
のイオン濃度が低い場合には種々の金属を電極として採
用することができるが、生物の培養するようなイオン濃
度の高い場合には白金黒電極が適していることが明かと
なった。生物培養時においても比較的イオン濃度の低い
場合には白金電極、ステンレス電極等が使用できるのは
もちろんである。First, a metal electrode to be mounted on the electrode for measuring a biological amount according to the present invention was examined. Figure 1 shows the electrolyte (20mM
An example of measuring the frequency characteristic of the electric capacity by inserting a pair of electrodes (electrode area 1 cm 2 , distance between electrodes 40 mm) into a -CaCl 2 solution is shown. Here, the capacitance rapidly increases toward the low frequency side, which is due to the electrode polarization. It is known that the influence of this electrode polarization shifts to the high frequency side as the ion concentration increases. FIG. 1 shows the results of measuring the frequency characteristics of electrode polarization for various metals in the present invention. In FIG. 1, 1 is a platinum black electrode, 2 is a platinum electrode, 3 is a stainless steel electrode, 4 is an aluminum electrode, and 5 is a copper electrode. From this, it is clear that various metals can be adopted as the electrode when the ion concentration in the solution is low, but the platinum black electrode is suitable when the ion concentration in the solution is high and the concentration of ions is high. It was Needless to say, a platinum electrode, a stainless steel electrode, or the like can be used when the ion concentration is relatively low even during biological culture.
このような材料からなる金属電極を用いた本発明に係る
生物量計測用電極について、その理解を深めるため構造
を簡素化した第２図に示した参考例を参照しながら説明
する。The biological amount measuring electrode according to the present invention using the metal electrode made of such a material will be described with reference to the reference example shown in FIG. 2 in which the structure is simplified for better understanding.
本参考例において、電極21は、一対の金属電極（例えば
電極面積:4cm２）を例えば2cmの間隔をおいて平行に設
置している。なお、電極の設置数は一対に限定されず必
要あれば更に多数としてもよいし、また電極面は同一平
面上に設置してもよいし、正対位置に設置してもよい。
本電極は、誘電体である基材22上に一対の金属電極21を
電極相互の位置関係が変化しないようにしっかりと固定
し、各電極にリード線を取り付け、リード線23は基材内
を通すことにより培養液と電気的、物理的に分離したも
のである。基材からでた各リード線は２本に別れ（電流
用コードと電圧用コード）計測装置（図示せず）に接続
する。なおリード線は、シールドすることなくそのまま
用いてもよいが、本実施例においては、外界の電波等の
ノイズをカットして更に正確な計測値を得るために、シ
ールド線24とした。各リード線23のシールド24は、基材
22を出たところで互いに電気的に接続した。図中25はそ
のシールド接続部を示し、26は接続端子を示す。In the present reference example, the electrode 21 has a pair of metal electrodes (for example, an electrode area: 4 cm 2 ) arranged in parallel at intervals of, for example, 2 cm. The number of electrodes to be installed is not limited to one pair, and may be set to a larger number if necessary, and the electrode surfaces may be installed on the same plane or may be installed in a facing position.
This electrode firmly fixes a pair of metal electrodes 21 on a base material 22 that is a dielectric so that the positional relationship between the electrodes does not change, and a lead wire is attached to each electrode. It is separated electrically and physically from the culture solution by passing it through. Each lead wire from the substrate is divided into two (current cord and voltage cord) and connected to a measuring device (not shown). The lead wire may be used as it is without being shielded, but in the present embodiment, the shield wire 24 is used in order to obtain a more accurate measurement value by cutting noise such as radio waves in the external environment. The shield 24 of each lead wire 23 is a base material
At the exit of 22 they were electrically connected to each other. In the figure, 25 indicates the shield connection portion, and 26 indicates the connection terminal.
第４、５図に本電極を用いて20mM,40mM,60mM,80mM,0.1
M,0.15MのNaCl溶液を測定したときの周波数特性を示
す。生物の培養液の様に電気伝導度の高い試料について
電気容量を測定する場合、計測装置から電極までのリー
ド線によるインダクタンス成分の影響が大きくなる。第
４図は第２図に示す電極の接続端子からシールド接続部
までの部分の補正を行った場合の測定結果である。イオ
ン濃度が増加するにつれ100KHz付近以上の周波数帯域で
測定値が大きくマイナスになる。これはインダクタンス
の補正が不十分のためと推定し電極部までの補正を行っ
たところ第５図に示すように電極特性を改善することが
できた。なおインダクタンス成分の補正には周波数300K
Hzでの値を用いて行った。これから周波数300KHzにおい
て電気容量の測定をおこなえば、本電極をもちいて培養
液中のイオン濃度が変化しても生物濃度の計測が可能で
あることが明かとなった。Figures 4 and 5 show that this electrode is used for 20mM, 40mM, 60mM, 80mM, 0.1
The frequency characteristic at the time of measuring M and 0.15M NaCl solution is shown. When measuring the capacitance of a sample having a high electric conductivity such as a culture solution of an organism, the influence of the inductance component due to the lead wire from the measuring device to the electrode becomes large. FIG. 4 shows the measurement results when the portion from the electrode connection terminal to the shield connection portion shown in FIG. 2 is corrected. As the ion concentration increases, the measured value becomes significantly negative in the frequency band above 100 KHz. It is presumed that this is because the inductance was not corrected sufficiently, and when the correction up to the electrode portion was performed, the electrode characteristics could be improved as shown in FIG. The frequency of 300K is used to correct the inductance component.
This was done using the values in Hz. From this, it was clarified that if the electric capacity was measured at a frequency of 300 KHz, the biological concentration could be measured even if the ion concentration in the culture solution was changed by using this electrode.
第３図は、本発明に係る生物量測定用電極の一実施例を
図示したものである。本実施例においては、基材32に装
着した各電極31に、（第２図のようにリード線23を各１
本ずつ接続するのではなく）リード線33を２本ずつ（電
流用コード、電圧用コード）接続するとともに、リード
線33（本実施例には全部で４本のリード線が図示されて
いる）はシールド線34とし、しかも各リード線33のシー
ルド34は基材内で電気的に接続した。第２図に図示した
実施例においては、シールド接続部25を基材22の外部に
設けたが、本実施例においては、シールド接続部35は、
基材32内のしかも電極31に近い位置に設けた。基材内に
おいて電極に可及的近い位置ですべてのコードのシール
ドをしっかりと接続するほうが特性がよくなることが判
明したからである。なお、36は接続端子を示す。FIG. 3 illustrates an embodiment of the electrode for measuring a biomass according to the present invention. In this embodiment, each electrode 31 mounted on the base material 32 is attached to each electrode 31 (each lead wire 23 as shown in FIG. 2).
Two lead wires 33 (rather than connecting them one by one) are connected (two current cords and one voltage cord), and lead wires 33 (four lead wires in total are shown in this embodiment). Is a shield wire 34, and the shield 34 of each lead wire 33 is electrically connected in the base material. In the embodiment shown in FIG. 2, the shield connecting portion 25 is provided outside the base material 22, but in this embodiment, the shield connecting portion 35 is
It was provided in the base material 32 and at a position close to the electrode 31. This is because it has been found that the properties are better when the shields of all the cords are firmly connected to the electrodes as close as possible to the electrodes in the substrate. Reference numeral 36 indicates a connection terminal.
第３図に示した生物量測定用電極を用いて、20mM,40mM,
60mM,80mM,0.1M,0.15MのNaCl溶液を測定したときの周波
数特性を第６図に示した。第６図から明らかなように、
測定したすべてのイオン濃度において電極分極の影響が
ないとみなせる300KHzより高周波側においてほぼ一定値
をしめし、上記の電極にくらべ電極特性が非常に改善さ
れることがわかった。Using the biomass measuring electrodes shown in Fig. 3, 20mM, 40mM,
The frequency characteristics when measuring 60 mM, 80 mM, 0.1 M, 0.15 M NaCl solutions are shown in FIG. As is clear from FIG.
It was found that the electrode characteristics were significantly improved compared to the above electrodes by showing a nearly constant value at a high frequency side above 300 KHz, which can be regarded as having no effect of electrode polarization at all measured ion concentrations.
このように、本電極をもちいれば生物培養槽等のように
イオン濃度が高く、かつイオン濃度が変動する場合にも
生物を含む培養液の電気容量を安定に測定できることが
明かとなった。また複数の周波数で、測定結果から生物
濃度の算出が可能となり測定精度の向上がはかれること
がわかった。As described above, it was revealed that the use of this electrode makes it possible to stably measure the electric capacity of the culture solution containing organisms even when the ion concentration is high and the ion concentration fluctuates as in a biological culture tank. Moreover, it was found that the biological concentration can be calculated from the measurement results at a plurality of frequencies, and the measurement accuracy can be improved.
（発明の効果） 本発明における電極を用いることにより、従来サンプリ
ングすることなく測定することが不可能であった。培養
槽内の生物量オンライン計測を可能とするという従来な
しえなかった新規にして卓越した効果がえられた。(Effects of the Invention) By using the electrode of the present invention, it has been impossible to perform measurement without sampling conventionally. A new and outstanding effect, which was previously unattainable, was obtained by enabling online measurement of the biomass in the culture tank.
したがって本発明によれば、微生物、動物細胞および植
物細胞量を非破壊的に測定することができ、バイオテク
ノロジー、ワクチン製造、微生物、動物細胞および植物
細胞を用いる実験、研究の技術用野、その他各方面にお
いて広く本発明を利用することができる。Therefore, according to the present invention, the amount of microorganisms, animal cells and plant cells can be nondestructively measured, and biotechnology, vaccine production, experiments using microorganisms, animal cells and plant cells, technical fields for research, etc. The present invention can be widely used in various fields.
第１図は、金属電極材料の相違による電気容量の周波数
特性の変化を図示したものである。 第２図及び第３図は、本発明に係る生物量計測用電極の
参考例及び一実施例をそれぞれ図示したものである。 第４図及び第５図は、第２図に図示した生物量計測用電
極を用いて、各種濃度の食塩水溶液を測定して得られた
周波数特性を示し、そして第６図は、第３図に図示した
生物量計測用電極を用いて同様に測定した周波数特性を
示したものである。FIG. 1 illustrates a change in frequency characteristic of electric capacity due to a difference in metal electrode material. FIG. 2 and FIG. 3 respectively show a reference example and an embodiment of the biological amount measuring electrode according to the present invention. FIGS. 4 and 5 show frequency characteristics obtained by measuring saline solutions of various concentrations using the biomass measuring electrode shown in FIG. 2, and FIG. 6 shows FIG. FIG. 7 shows frequency characteristics similarly measured by using the biological amount measuring electrode shown in FIG.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 昭55−138397（ＪＰ，Ａ) 特開 昭61−202122（ＪＰ，Ａ) 特開 昭63−191046（ＪＰ，Ａ) 実開 昭63−135172（ＪＰ，Ｕ) 実開 昭57−48465（ＪＰ，Ｕ) ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-55-138397 (JP, A) JP-A-61-202122 (JP, A) JP-A-63-191046 (JP, A) Actual development Sho-63- 135172 (JP, U) Actual development Sho 57-48465 (JP, U)
Claims (1)
属電極を電極相互の位置関係が固定された状態で装着
し、それぞれの電極にはリード線を２本取り付け、リー
ド線はシールド線とするとともに基材内を通すことによ
って液体媒質と電気的及び／又は物理的に分離する一
方、各リード線のすべてのシールドを基材内で電気的に
接続せしめ、且つリード線の電極と反対の端末に接続端
子を取り付けてなることを特徴とする生物量計測用電
極。1. At least a pair of metal electrodes are mounted on a base material which is a dielectric in a state where the positional relationship between the electrodes is fixed, and two lead wires are attached to each electrode, and the lead wires are shielded wires. While being electrically and / or physically separated from the liquid medium by passing it through the base material, all shields of each lead wire are electrically connected in the base material, and are opposite to the lead wire electrodes. An electrode for measuring a biological amount, characterized in that a connection terminal is attached to the terminal of.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63293671A JPH0663999B2 (en) | 1988-11-22 | 1988-11-22 | Biomass measurement electrode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63293671A JPH0663999B2 (en) | 1988-11-22 | 1988-11-22 | Biomass measurement electrode |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02140650A JPH02140650A (en) | 1990-05-30 |
| JPH0663999B2 true JPH0663999B2 (en) | 1994-08-22 |
Family
ID=17797733
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63293671A Expired - Fee Related JPH0663999B2 (en) | 1988-11-22 | 1988-11-22 | Biomass measurement electrode |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0663999B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0740009B2 (en) * | 1990-10-09 | 1995-05-01 | 株式会社神戸製鋼所 | Biomass measurement electrode |
| JPWO2007034550A1 (en) | 2005-09-22 | 2009-03-19 | ヒューレット−パッカード デベロップメント カンパニー エル．ピー． | Moving image distribution apparatus and method |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55138397A (en) * | 1979-04-13 | 1980-10-29 | Fujisawa Pharmaceut Co Ltd | Method of measurement of bacterium growth rate and device therefor |
| JPS61202122A (en) * | 1985-03-06 | 1986-09-06 | Tokyo Tatsuno Co Ltd | Liquid level/quantity measuring apparatus |
| JPH07117511B2 (en) * | 1987-02-04 | 1995-12-18 | 株式会社神戸製鋼所 | Method of measuring bacterial cell amount |
-
1988
- 1988-11-22 JP JP63293671A patent/JPH0663999B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02140650A (en) | 1990-05-30 |
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