WO2002042755A2

WO2002042755A2 - Tubular electrode

Info

Publication number: WO2002042755A2
Application number: PCT/EP2001/013839
Authority: WO
Inventors: Jochen Eshold; Guido Schwartenbeck; Michael Borchardt
Original assignee: Institut für Chemo- und Biosensorik Münster E.V.
Priority date: 2000-11-27
Filing date: 2001-11-27
Publication date: 2002-05-30
Also published as: WO2002042755A3; DE10058746A1; AU2002216061A1

Abstract

The invention relates to an electrochemical sensor comprising at least one electrode and one tubular plastic sheathing that forms an inner volume. The sheathing is electrically conductive at least in areas along the periphery thereof and/or along the longitudinal direction of the tube between its inner side that delimits the inner volume and its outer side. The electrically conductive areas of the inner side or of the outer side form the electrode.

Description

Tubular electrode

The present invention relates to an electrode like this. for example in the field of sensors, in particular bio and chemical sensors.

Such electrodes or sensors are disclosed for example in EP 265 072 AI. In this publication, the electrode consists of a porous tube with a diameter of approximately 100 μm, the pores of which are filled with an ion-selective cocktail. The signal is picked up as a discharge contact by means of a wire that is wound around the electrode.

Tubularly arranged PVC membranes are also used in biosensors in "Biomedical Engineering" Volume 36, Issue 11/1991, pages 271-284. However, the membranes only serve as carriers, while the signals are obtained via a silver chloride-cement fixed section. ω ω → o cπ o Cπ o cπ

rt vp T) rt P- φ 0 P- 3 p ⁾ M H- rt α α CΛ <φ rt Hi t? s: 3 CΛ T3 - ¹ σ

H 0 P- CD üi r → 0 01 Φ 0 H 0 Φ Φ 0. H- rt φ 01 H- P> 0 H- 0 Ω φ φ Φ H- Φ

P- 0 0 H rt Φ rt 0 CΛ Hi H 0 01 Φ Φ HO Ω φ Hi Φ 3 rt 0 ^J H H- W φ P-

01 ιP ri "CΛ? T H- er TS 01 3 Hi> 0" w iQ H- H- 01 rt rt rt

O Φ P- O rt CΛ 0 tr Φ 0 Φ H- iQ H Φ .fD 0: 0 Φ Φ rt P ⁾ Q 01 Ω "φ H- ö 0 ¹ 0 0 H φ 0 H- H- 0 φ 0 sQ Hi 0 H er H- I- ¹ Ω 0 ¹ 0 <l H 0

P- P- P- P- 0 t- ¹ 0 0 P, 3 Ω P ⁾ 0 IQ> O Φ Φ 0 0 ^* rt α P- Φ ιP t → P- o CD Φ ω 0 3 & Φ 0 P ⁾ 0 pj: 0 '0 0 0 P ⁾ H CΛ H- φ Cü

Φ ω P- CΛ Ω φ φ Φ 3 «3 er 0 & α Hi Hi IQ er 0 rt φ Φ W H- 0 Φ 3 M o Φ

P- rr ^J H 0 ^{^} rt 01 0 ^{^} IQ r → IQ Φ H Φ (- ^■ O: 01 0 H et H P- ^ H CΛ ιQ pi: Φ T) P ⁾ Φ N Ω 0 NH Φ H rt 01 cn Φ t → Hi

Hl P. Ω 0 -> Ω Φ 0 0 P> 01 er H- 0 α 0 ^J 0 0 ^ 13 Φ HW o O pj: CD ^ 0 ^J 0 Φ 0 0 0 ^J 3 ιq et O Φ 0 Φ iQ H rt Φ 0 ^{^} φ 3 0 rt ^* H o Φ 0 P- EP D. α pj: H- ü Φ s: Hi CΛ H Φ o HH H- H- 01 H ιq

P- t P rt Φ CD P> ÖD iQ Φ 0 H- s: P> rt Hi S! H H- Φ 0 s O CTi rt iQ ^ er Hi 0 00 P) 0 φ H rt Φ H- Ω Φ 0: Φ Φ l- ^J 01 0 H Φ Φ 0 •

0 CD 3 Φ pi: 01 0 Ω er 0 P> H 0 ^J O 0 ^J H- H H- Ω 0 er 3 Ö3 0 Φ

0 0 0 Φ. ¹ φ - & 01 0 'Φ Φ 0 Ω, α φ! - ^■ HH 01 Hi Φ ^{^} α Φ ι P. 0

0 01 cn et CΛ P- P- Φ ⁾ 01 ΪJJ H 01 H- Φ (- ^■ rt Φ 0: iP Φ H- H- 0 h- ¹ o. Rt- rf J 13 <P rt H? =! H rt Hi T3 Φ 23 0 H- iQ Φ α o rt φ 3 o OP "P- Φ 0 rt Φ 01 H- H 0 φ Φ s: CΛ 0 0« Φ H- 0 H- H- o er rt Hi ffi s 0 H- T3 0 0 <H H- iQ H- 0 - O 3 0 Φ N 0 rt Hi

P- o Hl P- N 0 ⁾ CΛ IÖ et H Ω Φ Ω 01 3 Φ H ιQ iQ Φ 0 01 0 0 Φ Hi → Mi fl CΛ g 0 rt Φ 0: 0 0 'H - Φ H- 0 0 0 rt H- he 01 ιP H Φ Φ

Hi CD Ω X \ 3 rt CΛ 0 & Ω 0 s: rt Φ JN ⁾ O Φ φ Φ H- 0

CD 01 H Φ O P- ω rt H- 0 ¹ SO, J α H Φ 0 i → 0 M? , 0 01 (- ^■ s: - 0 er rf O Hi P- 0 OK Φ Φ CΛ M 0 H- Φ 0 (0 H rt. Φ o φ 0 H- Φ 0

0 ^J O 0 CΛ Φ fi Hi P ⁾ 0 iQ Ω. φ P> φ? CΛ Hi H- 0 0 0 Φ 3 H

P "P" Φ H Φ N Hi 0 t? D Φ IQ 0 0 M O: iQ rt H- 01 P, et rt

P> 0 ιq ^ is; rt \ → ιQ 9 Φ t? H- φ H 0 Φ Φ 0 H φ Φ H- rt o Q v 0 CD: Φ rt H- r Φ φ Φ P>: (- ^■ ιq (- ^■ 01 0 Hi. 0 s: P, 0 \ - > H <er p.

Φ o 0 p- P "CΛ φ? T £! & O O: φ φ ^' H- H- Φ o 0 0 φ Φ Φ H- Φ 0 φ

H 0 ^J • H φ P- Ω CΛ _^ rt Φ Φ ω 0? Φ iQ 0 0 0 Φ 0 iQ w 0 01 H 01 3

0 Ω? 0 0 ^J rt H er 0 rt rt H ⁾ P. 0 0 ιp rt P. rt Hi K ι ιP 0 σ 0 0 ^J rt Φ Φ O Φ • H rt 0 0 Φ H- H- - _* → O: φ → ιQ H ι-3 0 0f Φ 0 - WON 0 H 0 H- Φ <! Φ 0 pj: H v

Φ oi H Φ ω o Φ rt H Φ. l- ¹ <! H s: Φ iQ 0 3 CΛ 01 φ 0 er o Tf φ

P- o 0 Φ Ω P- 01 • Φ o P> Φ oi o H- rt 0 i? he rt ϊö 0 w 01 Φ 0 ^J Φ 0 ^•

Ω S P- ^J P "Φ Φ 0? THHH rt p. Φ H 0:

^ 0 ⁾ s: 3 φ er H- Kl H- 0 rt rt rt IQ α K Φ φ Φ o «Hl 01 Φ er

N 0 P- φ 3 φ 0 0 0 rt H Φ H- Φ Φ φ 01 H P- 01 - 0 rt rt Ω P. 0 Φ

CD rf- P- Φ 0 P- H Φ rt Φ O H- iQ 3 ^■ 0 Φ o Φ H 0 0 ow φ 0 H

P- D CD ιp CΛ Φ H Λ H Φ PJ: et t 0 JH Φ 01 0 "j Φ 01 01 rr \ → oi CΛ Φ Ω P- Ω 0 φ 0" H & α? H rt 0 P ⁾ CΛ rt iQ Hi 0 P-

P- CD P- 0 0 "Ω 0 0 J ⁾ O: OH Φ Ω ⁾ 0T. 01 cn o ιp CD P ^{1 ^} 0 Φ Φ 0 X Hi M TJ 0 OH - 0 Φ rt N Φ O 0

P ¹ ω er <1 0 Φ 0 H- 0 φ rt (- ^■ PJ 0 Φ α Φ Hi HOX d 0 0 φ ω CD CD Φ 0 P Φ P, J Φ H. Φ CD rt. Φ 0 φ - W Hi H- ü ω (D 13

O t τ P- H 0 rt 0 Φ o H Φ 0 oi 0 H- ω Φ Hi ω ow 0 01 s: 1 3 «P- 1 0 φ Φ S! et 0 • • 01 P ⁾ H- φ Ω er O: φ o CD! 0 ö Φ H et 1 N rt ^ r- 0 H- 01 0- H 1

0 1 H- O 1 0 1 1 0 O Φ Φ 1

1 1 1 1 n Φ 1 0 1

the carrier material as well as the discharge contact for material-selective plastic membranes on the inside (in the case of fixed drainage to the outside) or on the outside (in the case of liquid drainage inside the hose). The plastic tube itself can also be impregnated with material-selective material, so that it directly represents a material-selective electrode. For example, a silicone tube made electrically conductive by means of embedded metallic particles is suitable for such an electrode.

An advantage of the inventive hose-like jacket is that a co-extrusion with other membranes membrane which are to be applied to its outside or inside and are also made of plastic, is possible, so that a strong covalent bond between the membrane and the ^• tubular support material ^' arises.

In particular, any connections of different hose pieces, for example by gluing or suitable connecting pieces, are possible using the hose-like jacket according to the invention. The hoses can differ in terms of their diameter or length, among other things. This enables each piece of tubing to have its own function, for example as a reference electrode, for pre-oxidation or the like. A multi-sensor unit is therefore possible that has no dead volume, has short response times and does not interfere with the measurement depending on the flow behavior.

By using different electrodes at different distances. or with different lengths used, the time sequences such as reaction times, incubation times, measuring times and the like can be determined, recorded and controlled. Such a microelectrode array consisting of pieces of tubing connected in series constitutes a "lab-in-tube".

The plastic of the jacket can be made electrically conductive and / or electrochemically active by means of electrically, conductive and / or electrochemically active additives, such as, for example, metallic particles and the like. By varying the additional quantities, it is possible to provide a layer with a defined number of particles over the thickness of a particle monolayer on the inner or outer side of the hose, the layer thickness of the layer then corresponding to the particle diameter, i.e. it is possible to define a layer in particle size layer thickness.

The incorporated electrically conductive and / or electrochemically active additives or particles each represent a type of microelectrode, so that there is a microelectrode effect with the better response behavior of the sensors known from this. If a further layer with a greatly reduced particle content is applied to the inside or outside of the jacket, this microelectrode effect can be further enhanced.

Silver particles are suitable, for example, for the solid derivation of ion-selective membranes applied from the outside or inside, while platinum as a carrier or pre-oxidation electrode for amperometric sensors or also as a carrier and working electrode for enzyme layers applied inside or outside with cυ ω t → cπ o Cπ o Cπ o Cπ

The signal (tapping) on the transducer can therefore be dispensed with. It is possible, however, to enable the clamping, for example, a particularly extruded ^'tab on the hose.

Such an arrangement allows, for example, an ion-selective electrode with an enzyme membrane to be easily produced in any layer sequence. A microelectrode array can also be implemented using a plastic layer containing a few conductive particles in layer thickness. A plastic hose that is normally made electrically conductive with particles then serves as a carrier and drain. A combination of different electrodes, for example for sodium, potassium, pH, as reference electrode and the like, is also possible. These can be connected to one another via connecting pieces without dead volume or using adhesive technology.

Some examples of electrodes according to the invention are given below.

Show it:

Fig.- 1 the structure and use; a conventional ion selective electrode;

2 shows the structure of an electrode according to the invention; and

FIGS. 3 to 10 further electrodes according to the invention.

1 shows a conventional ion-selective electrode 1, in which an ion-selective layer 3 and an immobilized layer are placed on a metallic electrode 2 Layer 4 containing enzymes is applied. The analyte 5 contacts the enzyme layer 4, while the signal is derived from the metal electrode 2 via a conductor 6.

2 shows an electrode 1 according to the invention. The usual lateral layer sequence as shown in FIG. 1 is replaced by a hollow cylindrical structure. As the outer jacket made of plastic, the electrode 1 has a hose 2, on the inside of which an ion-sensitive layer 3 and an immobilized enzyme-containing layer 4 is applied. The inner volume 7 of the electrode 1, through which, for example, analytes or analyte solutions can flow, is enclosed within the enzyme layer 4. The arrangement consequently forms a flow electrode. This is shown in FIG. 2A, while in FIG. 2B the individual layers 2, 3 and 4 are drawn separately from one another.

Here, as in the following, corresponding reference symbols are used throughout for corresponding elements.

3 shows a further ion-selective electrode with an enzyme membrane. The jacket 2 consists of a silicone tube which is filled with silver particles in the plastic. A silicon layer 3 with ion-sensitive components, which are embedded therein, follows as the ion-selective layer. The innermost part is a silicone foam layer 4, which contains immobilized enzymes.

FIG. 4 shows a multi-electrode array in which a jacket 2a consists of a silicone tube which is coated with electrically conductive particles in the plastic. ω o P ¹ p>

Cπ o cπ o cπ o cπ

P- 01 <! ^ s; s: M φ P- φ P- Φ 0

H 0 f3 ιp P- H Φ er • CΛ P. fr

<. P- φ φ rt o p. σs H

P "P- P- 0 0

P "Φ 0 0 S3 P-

01 0 N iP φ Φ rt Φ iP X φ P- 0 p>: P- oi P- o rt

0 0 01 01 13 φ r → p. N rt Ω H Ω

P- Φ 0: 0 Φ ιp P ¹ Ω φ Φ 0

Φ 0 fT 0 rt M 0

0 Φ Φ P-

0 P- s: Φ

£ CD φ φ for W

CΛ 0 0 H rt Φ o rt P ^, H Hi

H: he φ φ o Φ

P- Ω N P- 0 P. 13

0? R X 0 • Φ Φ

0 Φ N 0 0

0 Φ P) N iP 01 00 P ¹ 0 for 0 O:

Φ 0 Φ er P- 0 P- 0 fV

Φ 0 φ φ rt

P- 13 iP H CΛ 0 H

01 Φ P "φ O

T3 Φ o Φ 3 P- P.

P- Oi H fr 0 Φ φ rt P. rt tu 0 → Φ 0 H φ φ

01 Φ o P- 0 P>

XP ¹ rt P, CΛ rt P. φ rt • Φ ^» ö 01

P- 0 P- Ή P.

01 H φ 13 0 φ X 0 et → φ 13

P- Φ Ω Ω

Φ ^ P- "tr

0 P- P- Φ iP

CΛ iP s: 0 0 φ p- p- • φ α P, Hl tr Φ P- Φ:

13 σs 01 P- 13 tr

Φ P- ω φ 0 H

0 rt

ω ω [\ 3 t → p> cπ o cπ o Cπ o Cπ

3 t? 01 H t → oi g fr X P- 0 3 ^ er P. oi r → rt rt H φ 13 ^ p, rt CΛ N CΛ XHM φ P ¹ rt 0 P- T3 φ O: φ 0 0: p- 0 P- T3 0 P- 0 S P- φ P- Φ Ω 0 P- 0: t → P- 0

0 φ 0 r P- EP 0 H tr P- EP vp rt Φ p- O 0 0 P- ^ P 0 0 tr 01 0 tr Φ ιp P.

CΛ f \ → ^ o φ 1 0 rt. Φ • P- 01 φ er 0 ιp 0 N φ • 01 \ → 0: H fr Φ

Ω et et P- 0 \ → Φ Φ Ό O φ H P- Cfl • 0 Φ <l Ω 0 rt φ et 0 tr K 0 P φ 01 0 <! P. tr M CD 0 φ 01 1 ot → 0 co tr 0 N 0 13 -J t → O 0 • X 0 Φ φ ^ → 01 l_J. '0 ^ tr ¹ 0 0 0 01 Ω l → ω P- o 3

0 ιp! φ Q. H 13 01 Φ N 1 φ → 0: CΛ Φ rt N rt tr P- rt P. N P-

0 Φ → φ P- s! Hi P- fr Φ X 01 Φ H 0 01 0 φ Φ H 01 Ω 0 p. φ Φ rt

Ω ^■ P. O 13 oi Φ 0 g et P- o φ P- 0 10 0 P- Φ rt tr rt P- P- Φ T Φ X φ 0 P- tr Φ 0 H iP P- 0 P- p ^ - φ *; CΛ <P Ω 0: rt φ t → ιp P-

»P. n P- φ 01 rt H EP O et Φ → P- 0 0 H 01 Ω te rt f Ω N 0 rt 0

0 01 0 Hi X Φ Φ 01 P- H 01 er Φ tr e Φ s "0 Φ M er H φ rt P- 0: φ H rt 01 Φ 0 o P ¹ t → Φ 0 Φ P- t → Φ

Φ vP 13 φ H 13 tr H Ω P- g 0 φ Φ et CΛ 0 0 = P- Φ φ P-

P- φ Hi φ rt et P- 0 Φ φ Φ 0 s; P- Φ Φ 0 0 0 o 0 P- φ fr H. 0 Φ

CΛ P- P- P. Φ t → Ω φ H EP rt Φ o H Ω Hi Φ P. 0 Φ H rt Φ H rt 0 X P- <! 01 fr 0 X N Φ P- P, 0 3 tr Φ φ Ω 01 H <!

Φ Φ P. φ φ Φ Φ P- Φ O X Φ H P "H oi Φ Hi CΛ 0 H tr φ <! O o

P- CΛ 01 Φ 1 0 = rt Φ H o P, H → 0 - Φ P- rt Ω P- rt 13 0: H tr H H φ o O g <!

3 \ → 0 H H CΛ er Φ φ s: P. CΛ Hi rt * P H

P- et iQ Φ Ω 0 0 p P- et Φ er 0 ι tr 0 o Φ Ω 0 0 0 0 ^ O 0 13 fr

H • 01 P- 0 tr tr Φ 0 Φ Φ 0 P- 0 P- g WHH Hi fr O: P- P- t → φ sQ rt → 13 01 1 rt P. H Φ rt 0 Φ Hi Φ Φ Ω rt rt 0 0 P- → 0 Φ

P- ^ 1 Φ Φ O 0 Φ P- Φ 01

0 3 0 0 Φ Φ Φ H: EP • tr P- er 0 0- er 0 0 er

P- 3 13 0 H Ω H 13 H tr 01 iP l → Φ 0 rt 0 rt s: iP 0: Φ Φ Ω O: 1 01 tr Ω Dd N P- 01 P- g H rt σ Φ rt 0 rt P - 10th

0. EP H tr N sQ ι-3 tr φ Φ Ω o sQ Φ Φ P- P- t → o 0 Ω 0 H • P- 0 01

01 g 01 0 t → er tr Hi P- 0 tr tr • EP 0 Φ Φ H V. Φ o O Ω 0 <!

Q. P> 0 O: rt P- P- rt 01 10 P- N Ω CΛ P- Φ 0 0 O O

0 σ iP P- 0: H Ω Φ__ φ Φ P- T3 Φ \ → Φ CO Φ P- ^ 0 0 Hi 01 H CΛ 0 φ 0 13

0 CΛ P ¹ Φ Ω Φ tr P. 0 Φ P- 0 0 P- 0 Φ P- rt t → 0 01 Ω Φ 0 P- iP ip N Ω P- 01 f 0 | -jl → φ • P "rt er 0 CΛ P- P- P "rt 0 't → α 0 M Φ φ φ tr Ω .Φ Φ t → φ P- CP" iP P- 0 Φ Φ rt O CΛ P "H Φ φ t → 01

0 P- \ → tr P- O 0 Ω φ 0 φ φ Ω H P- <! 0 P- Φ φ Φ ^. t → H Φ Φ ιp 0 fr * 1 O CΛ r tr 13 H tr iP • o er Φ ^' 0 Ω 0 et P. tr

P »rt 0 Φ Φ O P- rt P * Φ P- Hl V φ N 0 Φ α 13 fr rt H g et Φ p> Ω P- et Φ P- 01 CΛ 0 0: φ t → CΛ ö 0 P - φ 0 H Φ 01 O g φ H 0

0 Φ tr rt 01 P- H üi P- g Ω rt H 0 rt P- 10 01 H 0 Φ> Ö ς Φ EP O p- CΛ rt 01 Φ Ω φ Φ tr P- fr Φ φ t → H ü 10 0 H Φ EP 01 er 0 rt IS! Φ Ω 0 tr EP → O Φ rt 10 r → 0: O P- tr "t → Φ Φ O: Φ P-

P- Φ 0: - 0 P. tr Φ 1 0 0 H P- ^ H M 0 EP φ 0 = <! P- H Ω t → P- 01 0 0

CΛ 0 Ω 13 0 Hi o rt P ¹ <P Φ → 0 o. 01 O tr 0 Φ 0 T 0 P- 0 0 Ω <l P- 01 Φ Φ Φ H 01 <P 0 P- 0 Φ fr 0 t → g Φ 's 0 t → 0 0 Φ 0 tr O 0 oi o 0 for 13 X Φ Φ Φ 0 o rt 10 X r → 0 0 Hi 0 P- p P. 01 0 0- 1 rt Φ ω φ 0 NH 0 P- H o

Ω t → 0 01 s: H Φ rt 0 & LxJ H 0 Φ P- Φ rt 0 Φ Φ O P. er et P ¹ £! CD 3 pj CD J3 ^ P PJ CD 0 01 - - 1 E → 1 & H- D

P- p- oi Φ P- 0 0 0 Ω O ιq 1 P- P- P

P- W α φ Φ rt X CΛ Φ Φ P- φ → 1 01 CΛ er P. oi fr H 01 0 1 Φ Φ 0 H t → Φ 1 0 0 0

0 0 φ P- Φ φ 1 Φ 3 sQ fr 0 0 1 er P- H 0 rt P-

1 0 1 P- 13 Φ 0 for Φ Ω 1 Ω P- 1 Φ 1 1 1 P- tr tr φ

Divide the interior of the jacket 10 into three compartments 12a to 12c. Different liquids can now flow through these compartments or different measurements or reactions can also be carried out in each of the compartments through different design of the membrane layers 3a to 3c. In this case, only the regions 2a to 2c are configured to be electrically conductive along the circumference of the jacket 10, so that otherwise the three compartments are electrically insulated from one another. However, it should be noted here that the walls 11a to 11c can of course be provided in greater or lesser numbers and can also be designed to be permeable in order to enable new ways for simple integration of otherwise complex measuring devices.

Claims

claims

1. Electrochemical sensor (1) with at least one electrode and a tubular jacket

(2) made of plastic, which forms an internal volume, characterized by the fact that the jacket (2) at least in regions along its circumference and / or the longitudinal direction of the

Hose between its inner volume (7) delimiting inside and its outside is electrically conductive, the electrically conductive areas of the inside or the outside forming the electrode.

2. Sensor (1) according to the preceding claim, characterized in that the plastic of the jacket (2) contains electrically conductive and / or electro- ^' emically active additives.

3. Sensor (1) according to the preceding claim, characterized in that on the inside or on the outside of the jacket (2) at least partially a plastic layer is applied which contains electrically conductive and / or electrochemically active additives, the concentration the additives in the plastic layer is much lower than in the jacket.

4. Sensor (1) according to one of the two preceding claims, characterized in that the electrically conductive and / or electrochemically ac tive additives are electrically conductive or electrochemically active particles.

Sensor (1) according to the preceding claim, characterized in that the electrically conductive and / or electrochemically active particles at least partially consist of metals such as silver or platinum or of carbon.

6. Sensor (1) according to one of the preceding claims, characterized in that the jacket (1) additionally contains material-selective material.

7. Sensor (1) according to the preceding claim, characterized in that the jacket (1) additionally contains ion-selective material.

8. Sensor (1) according to one of the preceding claims, characterized in that a substance-selective membrane (3) is applied at least in regions on the inside or on the outside of the jacket (2).

9. Sensor (1) according to one of the preceding claim, characterized in that the substance-selective membrane (3) contains plastic as the matrix material.

10. Sensor (1) according to one of the two preceding claims, characterized in that the substance-selective membrane (3) is an ion-selective membrane.

11. Sensor (1) according to one of the preceding claims, characterized in that an enzyme layer (4) is applied at least in regions to the inside or outside of the jacket (2).

12. Sensor (1) according to the preceding claim, characterized in that the enzyme layer (4) contains plastic as the matrix material.

13. Sensor (1) according to one of the two preceding claims, characterized in that the enzyme layer (4) contains enzymes immobilized in plastic.

14. Sensor (1) according to one of the preceding claims, characterized in that the jacket (2) on the inside or ^' the outside is at least partially coated with silver chloride or platinum.

15. Sensor (1) according to one of the preceding claims, characterized in that the sensor (1) in the inner volume (7) and / or on its outside at least in sections contains a chloride-containing solution or a chloride-containing solution flows through or flows around.

16. Sensor (1) according to one of the preceding claims, characterized in that the jacket (2) is coated on the inside or the outside at least in regions with a plastic foam.

17. Sensor (1) according to the preceding claim, characterized in that the plastic foam contains metal particles.

18. Sensor (1) according to one of the preceding claims, characterized in that the jacket (2) has an electrically conductive tab.

19. Sensor (1) according to one of the preceding claims, characterized in that the interior (7) of the tubular jacket (2) at least two by at least one in the longitudinal direction of the tubular jacket (2) extending separating. wall (11a - 11c) formed, separate compartments (12a - 12c).

20. Sensor (1) according to the preceding claim, characterized in that at least one partition (11a - 11c) is at least partially semi-permeable or permeable and / or contains substance-recognizing substances.

^'21. Sensor (1) according to any preceding Ansprü- before, characterized in that the tubular _sheath. (2) has a round, rectangular, square or any other cross-section.

22: Use of a sensor (1) according to one of the preceding claims as an amperometric or potentiometric sensor, for example as a chemosensor, bipsensor or in particular as an ion-selective sensor.

23. Use of at least two sensors (1) according to one of claims 1 to 21 as an amperoiaetri see and / or potentiometric sensor arrangement, the at least two sensors being joined or glued directly or indirectly to one another.

24. Use according to the preceding claim, characterized in that the at least two sensors are bonded to one another at each of the adjacent ends in such a way that their tubular jackets form a common inner volume.