WO2015180753A1 - Arrangement and method for testing a measurement medium for the presence of helicobacter pylori - Google Patents

Abstract

In order to test a measurement medium for the presence of Helicobacter pylori, a sensor is used by means of which said measurement medium is tested for the presence of ammonia. Said sensor comprises a measurement arrangement having an electrical contact consisting of silver for monitoring an electrical measurement variable. Said electrical contact is arranged in a chamber that can be closed and/or opened, and said sensor comprises a device by means of which the electrical contact in the chamber can be screened at least from ammonia such that any ammonia that may be present is unable to penetrate the chamber from outside the sensor. Nevertheless, the device allows the screening to be removed such that any ammonia that may be present can enter the chamber. This screening of the sensor therefore allows the electrical contact to be protected up to the time at which the measurement takes place. As a result, the sensor can be brought, initially in an unaltered state, into the vicinity of the site of infection where the concentration of ammonia is at its highest. The measurement can then take place using an unaltered sensor.

Description

description

Arrangement and method for checking a measuring medium for the presence of Helicobacter pylori

The invention relates to an arrangement with a sensor for checking a measuring medium for the presence of

Helicobacter pylori. In particular, the invention relates to a shield of the sensor.

Helicobacter pylori (hereafter HBP) is a rod-shaped bacterium that can colonize the human stomach and be held responsible for a number of gastric diseases. In addition to gastritis, these include gastric ulcers as well as duodenal ulcers. In a chronic form, HBP can also cause stomach cancer. The prevalence of HBP is approximately 50% worldwide. The investigation of an infection with HBP therefore represents today an essential part of the Diag ^¬ nostik of stomach diseases.

An HBP infection can be treated, for example, with the aid of an eradication therapy consisting of a combination of different antibiotics. However, before such a therapy can be started, a reliable diagnosis is first necessary. If necessary, up to two independent proof tests must be positive.

Various direct and indirect detection methods for HBP are known. For example. can HBP infection after biopsy by microscopy or by means of a

Urease tests are detected. Another approach for the detection of HBP infection consists in carrying out a breath test based on the detection of the isotopes 13C and 14C in the breath after the patient specific, 13C or 14C was administered iso- topenmarkiertes agent at EXISTING ^¬ densein of HBP enters certain chemical reactions in the stomach of the patient so that 13C and 14C is formed and is out ^¬ breathes. All these methods of detection as well as other however, a low level of patient acceptance is common.

A concrete possibility of examination of the stomach on egg ne colonization with HBP in WO2010 / 094650A1 is the so-called gastroscopy ( "Ma ^¬ genspiegelung"). Here, such as. Described used a gastroscope, at the end of which two electrodes are located, However, gastroscopy is uncomfortable and potentially painful for the patient.

An alternative to gastroscopy is the use of a

Endoscopy capsule, as shown in more detail in WO2009 / 127528A1, for example. In this case, the endoscopy capsule is guided to a site to be examined in the gastrointestinal tract and a determination for Helicobacter pylori is carried out on site. WO2009 / 127528A1, in which other problems of the current HBP detection methods are explained, describes an approach for the detection of HBP infection based on the introduction of a corresponding sensor in an optionally affected hollow organ of a patient. The sensor is integrated into an easily swallowable endoscopy capsule and thus able to detect a metabolite of the HBP bacterium, for example ammonia, in the hollow organ and thus to identify the bacterium in situ. In one embodiment of WO2009 / 127528A1, the sensor has a superficial sensor layer of silver chloride, which undergoes a measurable change in property upon contact with the bacterium or with its metabolite. The property change is based on the dissolution of the silver chloroiod in the presence of ammonia, so that the corresponding sensor layer is degraded. This degradation of the silver chloride layer leads to a change in an electrical measurement of the sensor, for example, to a change in the electrical potential, the electric current or the electrical resistance. By measuring or monitoring one or more of these parameters, the presence of ammonia can be detected and thus concluded that HBP is present. A similar one Sensor is also used in the above mentioned WO2010 / 094650A1.

The HBP sensor is already fully functionalized when inserted into the measuring area, for example into the stomach of a patient. However, since the conditions in the stomach by Pati ^¬ ent to patient may be significantly different, their influence on the functionalization of measurement to measurement is not reproducible. So you do not know the information available at the time of measurement conditions completely, for example. Can be triggered at a high concentration of ammonia in the stomach of the reduction of silver chloride layer immediately after immersion of the sensor into the gastric juice, oh ^¬ ne that the actual measurement had already begun while in another case you first have to approach the infected area in the stomach. In addition, the conditions, in particular ^¬ sondere the ammonia concentration in the stomach continuously change so that the presence of ammonia does not make might as steep signal edge noticeable, but appears as a gradual slope of the measurement signal and is thus difficult to detect. Possible disturbances of the measurement by other substances contained in the measuring medium can therefore not be excluded. It is therefore an object of the present invention to provide a meaningful and reproducible way of detecting Helicobacter pylori in a hollow organ of a patient. This object is achieved by the ^device described in claim 1 ^¬ direction and by the method described in claim 15. The dependent claims describe advantageous from ^¬ designs. Of the invention is based approach is the sensor or its sensitive elements only at a desired time, for example. For the time of measurement initiation, in mög ^¬ lichst defined composition for the measurement Verfü- tion or to expose it to the test medium to be examined. This can be assumed that the conditions are known to start of measurement so that measurement result ^¬ se are more interpretable and meaningful.

The arrangement according to the invention has an HBP sensor for checking a measuring medium for the presence of

Helicobacter pylori by checking the medium for the presence of a specific substance in the medium. The particular substance is preferably a metabolite of HBP, ie especially ammonia. In this case, the measuring medium is the medium in which the measurement for the detection of HBP is carried out, i. in particular the gastric juice or, if it is an in-situ measurement, a nutrient solution. The HBP sensor now has:

- a measuring arrangement with at least one electrical contact, the electrical contact comprises silver, and where at ^¬ for detecting the specific substance on the measurement arrangement, an electrical measurement such as an electric potential, an electric current and / or electric.

Resistance is measured; The measuring arrangement is, for example, an electrode arrangement with a measuring electrode as electrical contact and a counter electrode. The counter electrode is preferably made of one of an acid, insbesonde- re hydrochloric acid HCl, unchanging metal and the measuring ^¬ electrode is made of silver;

 a closable and / or openable space in which the electrical contact is arranged; and

- a device with which the electrical contact in a first operating state of the sensor from a certain substance potentially having components of the medium being measured is at least shielded, so that the component of the measuring medium not from outside of the sensor ge ^¬ long in the space, even if the sensor is located in the measuring medium), so that a contact of the component with the measuring ^¬ electrode can be prevented, and with which the shield can be canceled and thus the component from outside the sensor can enter the room, so that the electric If necessary, contact in a second operating state of the sensor at least with the component of the medium to be brought into contact.

The shielding of the sensor, which protects the sensor until the time of measurement, is advantageously removed at the desired time of commencement of the measurement. In this way, the sensor can first be brought into the vicinity of the center of infection unchanged, at which the ammonia concentration is highest. Here, the measurement can be done on an unchanged sensor. Since the influence of ammonia on the sensor now sharply increases, is expected as before a possibly slow and so bad he ^¬ discernible change for the measurement signal and for the electrical measurement of a sudden change in place. Accordingly, the presence of ammonia and an HBP infection with RESIZE ^¬ ßerer security can be detected.

The device may be specifically designed for closing and / or opening of the space such that the component of the sample medium, in the first Be ^¬ operating state in the closed space, at least not enter from the outside of HBP sensor in the room, and so that in the second operating state If the space is open, at least the component of the measuring medium can enter the room from outside the HBP sensor and come into contact with the electrical contact.

The device may comprise a movable cover, which is arranged in the first operating state such that the space is closed, so that the measuring medium can not enter the room from outside the sensor, and which is movable such that the space by moving the cover is openable, so that at least the component of Messmedi ^¬ ums get into the room and can come into contact with the electrical contact.

The electrical contact as well as optionally present further elekt ^¬ generic contacts in the form of flat strip electrodes or layer electrodes is applied to an outer surface of a sen ^¬ sorkörpers the sensor, wherein the movable cover is arranged such that it forms the space in the first operating ^¬ state in cooperation with the outer surface of the senors in the region of the electrical contact and closes.

Alternatively, the space may be a chamber extending into the interior of a sensor body of the sensor in which the electrical contact is located, so that the electrical contact is arranged inside the sensor body, wherein

the chamber has a chamber opening which can be closed and / or opened with the movable cover,

 - The chamber opening in the open state represents a connection of the chamber with an environment of the sensor, so that the measuring medium located in the vicinity of the sensor can pass through the chamber opening into the chamber and can come into contact there with the electrical contact, and

 - The movable cover is arranged such that it closes the chamber opening in the first operating state and opens the chamber opening in the second operating state.

The sensor thus has a sensor body with an outer surface, wherein the space inside the sensor body is arranged below the outer surface, so that the outer surface of the sensor is largely flat. This results in the advantage that the sensor is better swallowable or insertable for examination.

Advantageously, at least prior to the start of the test of the measuring medium, ie before the first measurement, a chloride solution is in the room, which is in contact with the electrical contact, so that a silver chloride layer forms on the surface of the electrical contact. This ensures that the sensor is in a defined state before the start of the measurement, since it is ensured that a silver chloride layer is present. Furthermore, the sensor may include a reservoir for a chloride solution, wherein the reservoir is connected to the space such that the chloride solution from the reservoir into the room is conductive, so that the electrical contact with the chloride solution comes into contact. This allows the

Sensor or the electrical contact in the meantime, for example. Between two individual measurements to functionalize again.

Before starting the test of the medium to be measured, the HBP sensor is functionalized such that the room is closed and there is a chloride solution in the room.

Preferably, the device is suitable ^¬ takes to open the space again and to close and alternately to place the sensor several times in the first and second Betriebszu ^¬ stand. This makes it possible to carry out several measurements, for example at different measuring locations.

The cover is preferably made of a material, which

 - at least for the particular substance impermeable and

- At least for a chloride solution, in particular for Salzsäu ^¬ re and possibly other, non-interfering substances, is permeable.

This ensures that even with shielded electrical contact, the chloride solution can act on the electrical contact, so that forms a silver chloride layer.

Alternatively or additionally, the cover is made of a material which

 - at least for the particular substance impermeable and

- Is soluble in the measuring medium.

In this case, the electrical contact for a bestimm ^¬ te time, which is required for the dissolution of the cover, effectively shielded from the particular substance. The shield is automatically released when the cover is released. A dedicated mechanism that will open the room is not needed. In a further development can also be a further electrical contact, for example., The counter electrode, are also arranged in the space on ^¬, so that the further electrical contact in the second operating state in conjunction with the electrical contact can be shielded.

Before the start of the review of the measurement medium of HBP sensor is functionalized such that the electrical contact to be ^¬ ner surface has a silver chloride layer, already before the checking of the measured medium is started or is before the electrical contact with the measuring medium in contact ge ^¬ introduced ,

The arrangement may, for example, be a catheter, a gastroscope, an endoscopy capsule or a biopsy forceps.

In a method for checking a measuring medium for the presence of Helicobacter pylori by checking the measuring medium for the presence of a specific substance in the measuring medium with the inventive arrangement wiord first spent the HBP sensor of the arrangement with shielded electrical contact to a first desired location in the medium , The shield of the electrical contact is released at a given time for a first measuring ^¬ phase, so that the desired measurement location on befind ^¬ Liche measuring medium can only come into contact from the desired time with the electrical contact. The electrical measurement is monitored at least in the first measuring phase ^¬ and from the monitored electrical measurement variable is closed for the presence of Helicobacter pylori in the measurement medium at the measurement location.

In a second measuring phase, after the first measurement phase, the shielding of the measuring electrode is restored, so that at least ^¬ component of the measuring medium in the second measurement phase ^¬ can not come into contact with the electrical contact. For a third measuring phase after the second measuring phase, the shielding of the measuring electrode is canceled, so that the measuring medium located at the measuring location can come into contact with the electrical contact in the third measuring phase.

Preferably, the electrical measurement is not only during odd-numbered measurement phases, but also in one

monitored even-numbered measuring phase.

An even measurement phase can be used to pass the HBP sensor to a different location from the first location.

In an even measurement phase, with shielded electrical contact, a chloride solution is passed into the room to form a new silver chloride layer on the surface of the electrical contact for later measurement.

In the following the invention and exemplary embodiments will be explained in more detail with reference to a drawing.

Show it:

1 shows an arrangement for detecting Helicobacter pylori in a first embodiment in a first operating state,

 2 arrangement for the detection of Helicobacter pylori in a first embodiment in a second operating state,

 3 arrangement for the detection of Helicobacter pylori in a second embodiment in the first operating state,

4 shows an arrangement for the detection of Helicobacter pylori in a second embodiment in the second operating state, 5 shows an arrangement for the detection of Helicobacter pylori in a third embodiment in the first operating state,

 6 shows an arrangement for the detection of Helicobacter pylori in a third embodiment in the second operating state.

Like reference numerals in different figures indicate like components.

1 shows a schematic diagram of an inventive

Helicobacter pylori (HBP) sensor 100 for checking a measuring medium 10 for the presence of Helicobacter pylori 20 by detecting a specific substance 30 in the measuring medium 10. The measuring medium 10 is preferably the medium in which the measurement for the detection of HBP 20 is carried out , In a specific application, the measuring medium 10 is the gastric juice in the stomach of a patient, and the specific substance 30 is a metabolite of Helicobacter pylori 20, ie in particular ammonia. If it is an in vitro measurement, the measuring medium 10 may be a suitable nutrient solution.

The HBP sensor 100 is a component of an arrangement 1 sensitive to HBP or ammonia 30 with which a patient can be examined. The arrangement 1 can, for example, a

Endocapsule, a biopsy forceps, a stomach catheter or even a gastroscope. FIGS. 1 to 4 show by way of example the design of the arrangement 1 as an endoscopy capsule. In this case, only the components are shown that are of interest for the invention, while those for a Endoskopiekapsel ty ^¬ cal components such as, for example, a permanent magnet or a camera, etc. are not shown. The same applies to Figu ^¬ ren 5 and 6, in which the arrangement 1 as the ones shown, provides gastroscope is.

The HBP sensor 100 has a measuring arrangement 110 for measuring an electrical measured variable with a first electrical Contact 115 and a second electrical contact 111. For example. the measuring arrangement 110 may be an electrode assembly, wherein the first electrical contact 115, a Messelekt ^¬ rode 115 and the second electrical contact 111 is a counter electrode. Other embodiments of the measuring arrangement 110, which allow a measurement of an electrical measurement, are also conceivable.

The electrode assembly 110 or the measuring electrode 115 and the counter electrode 111 are electrically connected to an integrated Kontrollein ^¬ 120 of the sensor 100th The control unit 120 can in turn be connected to an evaluation unit 190 of the arrangement 1.

The control unit 120 is used on the one hand in order to measure an electrical measured variable on the electrode arrangement 110. The electrical measured variable is, for example, an electrical potential, an electrical current or an electrical resistance. For the measurement, it may also be necessary for the control unit 120 to provide an electrical current or an electrical voltage to the electrode arrangement 110. On the other hand, the control unit 120 serves to ^receive the measured electrical measured variable and transmit it to the evaluation unit 190. Alternatively or additionally, the control unit 120 may, for example, the measured values. For later evaluation by the evaluation unit 190 spei ^¬ manuals. The evaluation unit 190 provides a desired Wei ^¬ terverarbeitung these data, which may consist, for example, in the extreme case. That a statement on the presence or absence of Helicobacter pylori is made at each measurement location.

The control unit 120 may, like the electrode ^arrangement 110, be arranged on or in the sensor 100. This is especially in the case of the formation of the arrangement 1 as

Endoscopic capsule conceivable. Generally, it is advantageous if the control unit 120 such remote ^¬ classified by the sensor 100 that it for example. In the investigation of the stomach a patient must be introduced to the sensor 100 in the patient's body not, but remains outside the Kör ^¬ pers. In such a case, the electrode assembly 110 can be connected to the control unit 120, for example via a cable. Depending on the design of the arrangement 1, such a cable may, for example, be guided over a catheter tube, a gastroscope tube or an actuating line for a biopsy forceps. The evaluation unit 190 may also independent and ent ^¬ removed from the sensor 100 may be arranged, in which case the communication between the control unit 120 and evaluation unit 190 for transmitting the data from the measurement of the electrode assembly 110 according to the arrangement of the control unit 120 via radio or via a cable.

The basic principle of the detection of Helicobacter pylori 20 is based on the fact that it is checked whether as a specific substance 30 a characteristic for HBP 20 metabolite in the measuring medium 10 is present. As mentioned, the characteristic metabolite 30 or, in the case of the specific substance 30, is ammonia. Ammonia 30 comes under normal circumstances in a hollow organ of the

 Gastrointestinal tract such as, for example, the stomach or only in very small quantities before. However, since ammonia 30 is a metabolic product of HBP 20, its detection suffices as a strong indication of the presence of HBP 20. Colonization of the stomach with HBP 20 can therefore be detected by measuring the ammonia content of the gastric juice or the ammonia content in the gastric mucosa becomes.

A possible, general measuring principle for the detection of ammonia 30 is based on the fact that the measuring electrode 115 a

Silver chloride layer has (not shown in detail), which in the presence of ammonia 30 enters into a chemical reaction with this. As a result, the

Silver chloride layer, since the salt AgCl of the silver chloride layer is converted by ammonia 30 into a well-hydrated soluble silver-diamine complex [AG (H3) ₂ ] and cleaved in chlorine Cl ^~ . The silver chloride is then removed from the electrode. For the detection of the particular substance 30 or of ammonia 30 in the vicinity of the sensor 100, the mentioned electrical measured variable is measured at the electrode arrangement 110. For this purpose, an electrical voltage U is applied to the electrode arrangement 110, ie between the measuring electrode 115 and the counterelectrode 111, with the aid of the control unit 120. In the event that ammonia 30 is present in the measuring medium 10 at least in the vicinity of the measuring electrode 115, this will cause the silver chloride layer to be degraded. This degradation of

Silver chloride layer leads to a change in the electrical measurement of the electrode assembly 110, for example, to a change in the electrical potential, the electric current or the electrical resistance, as soon as the

Silver chloride layer is at at least one point so far abge ^¬ builds that a layer lying below the silver chloride layer is exposed with a different electrical potential. In the case of the figures shown here, this would be the surface of the measuring electrode 115. By measuring or monitoring one or more of these measured variables with the aid of the control unit 120, the presence of ammonia 30 can be detected by determining a significant change in the measured variable and thus to the Presence of HBP 20 closed.

As explained in the introduction, the problem arises that at the beginning of the measurement, the measurement conditions are not necessarily sufficiently clear, so that the measurement results are subject to a certain degree of uncertainty. For measurement, the sensor 100 should be positioned at a certain position in the stomach. If now the sensor 100, for example, with the help or in the form of a

Endoscopy capsule, at the tip of a catheter or with biopsy forceps in the stomach and in the gastric juice ver ^¬ is introduced, can not be ruled out that the

Silver chloride layer 117 is damaged. Also, not enough shut, the sensor 100 and thus, in particular, the silver chloride layer 117 on the way to the measuring position in Ma ^¬ gene already at lower concentrations of ammonia comes into contact such that the silver chloride layer as partially 117 is reduced before the actual measurement starts. Furthermore, it is possible that by various

Chloride concentrations on the way to the site of potential shifts are caused, which has a similar effect on the measurement as the presence of ammonia. All this causes the measurement results to be falsified. A silver chloride layer 117 which has already been partially removed at the time of the actual beginning of the measurement can cause, even in the presence of ammonia 30, the corresponding change in the measurement signal due to a lower amplitude not or only poorly recognizable.

The sensor 100 therefore has a device 130 with which the measuring electrode 115 can be shielded by the measuring medium 10 or at least by a component of the measuring medium 10 potentially containing the specific substance 30 in a first operating state of the sensor 100, and in particular if the sensor 100 is located in the measuring medium 10. In shielded measuring electrode 115 at least the Components ^¬ te of the measured medium 10 to the specific substance 30, the measuring electrode 115 ^¬ therefore can not reach, so that the silver chloride layer is not attacked ^¬ 117th The device 130 allows besides the measuring electrode 115 as needed with the measuring medium 10 or at least with the component of the measurement Medi ^¬ around 10 and thus with the particular substance 30 or with the ammonia to bring 30 in contact by the shield in a second Operating state of the sensor 100 is canceled.

The possibility of shielding ensures that a contact of the measuring medium 10 and thus possibly a contact of the Ammoni ^¬ aks 30 is prevented with the measuring electrode 115, so that in the sequence, the silver chloride layer 117 can not unintentionally abge ^¬ builds, as long as the shield exists is. Also For example, it becomes possible to control other parameters influencing the measurement, such as, for example, the conductivity between the measuring electrode and the ^{counterelectrode} . Consequently, the state of the functionalized measuring electrode 115 and thus the measuring conditions are known. On the other hand, the possibility of eliminating the shielding when required allows targeted measurements under known conditions at certain positions in the measuring medium 10. To achieve this, the sensor 100 is initially connected to the desired measuring electrode 115 with a shielded measuring electrode

Location, for example, spent in the stomach. Once there, the device 130 is actuated and thus the shield aufgeho ^¬ ben. The measuring medium 10 then comes abruptly into contact with the measuring electrode 115, so that in the presence of ammonia 30, the degradation of the silver chloride layer 117 begins abruptly and a corresponding measurement signal can be detected.

In a first embodiment according to FIG. 1, the counter electrode 111 and the measuring electrode 115 are applied to the outer surface of the sensor body 101 in the form of flat strip electrodes or layer electrodes. The device 130 may, for example, comprise a movable cover 131 is also mounted in the closed state flat on the measuring electrode 115, so that between the Abde ^¬ ckung 131 and the sensor 100 and the outer surface 102 of the sensor 100, a thin space 140 forms, in which the measuring ^¬ electrode 115 is arranged. The space 140 is created accordingly causes 101 with a closed cover 131. A sealed cover 131, that the measuring medium 10 may not reach the measurement electric ^¬ de 115 by the cooperation of the cover 131 with the outer surface of the sensor 100 and the sensor body. Depending on the adaptation of the shape of the cover 131 to the underlying surface 102 of the sensor ^¬ body 101 and to the now located between the cover and the sensor body 101 measuring electrode 115, the volume of the cavity 140 may be more or less pronounced. In the extreme case, the cover 131 rests directly on the measuring electrode 115 and / or on the outer surface 102, ^{see also FIG} that the space 140 with closed cover 131 comprises only a minimum volume.

The movable cover 131 can, if necessary, be displaced, folded down or completely removed with the aid of corresponding devices (not shown), so that the space 140 is opened and the shielding is released and the measuring electrode 115 is exposed, so that the measuring electrode 115 has a contact point the medium 100 surrounding the sensor 100 comes into contact. This is shown in FIG 2, wherein the cover 131 has been folded down as shown in FIG. Such devices for corresponding actuation of a cover 131 are well known and will therefore not be explained in detail at this point.

The cover 131 may be a flexible membrane in an advantageous development that can be adapted ideally to the Oberflä ^¬ chenstruktur of the sensor body 101 and thus unfolds fewer disruptive influences during an investigation.

In a variant of the first embodiment, the cover 131 or the membrane 131 may be formed such that the counter electrode 111 can be shielded together with the measuring electrode 115 (not shown). The above-explained variant of the first embodiment relates only to the fact that the measuring electrode 115 can be shielded, since the counter electrode 111 is anyway insensitive with appropriate choice of material and shielding, for example. Against ammonia is accordingly not necessary. Nevertheless, the variant that the counterelectrode 111 is shieldable, for example. The advantage that it can be protected against any external physical influences ^¬ .

FIGS. 3 and 4 show a second embodiment of the sensor, FIG. 3 showing the sensor 100 in a first operating state with a shielded measuring electrode 115 and FIG. 4 the sensor 100 in a second operating state with the shielding of the measuring electrode 115 removed. The measuring electrode 115 is located in a chamber 132 which is arranged in the interior of the sensor body 101 of the sensor 100 and accordingly extends from the outer surface 102 of the sensor 100 into the interior of the sensor 100. The chamber 132 is a component of the device 130 with which the measuring electrode 115 can be shielded by the measuring medium 10 or at least by a component of the measuring medium 10 potentially containing the specific substance 30.

The chamber 132 has a closable chamber opening 133, which in the opened state represents a connection of the chamber 132 to the surroundings of the sensor 100, so that a medium 10 located in the vicinity of the sensor 100, for example the measuring medium, enters the chamber 132 where it can come into contact with the measuring electrode 115. In the closed state of the chamber 132, ie of the sensor 100 in the first operating state, the befind- in the vicinity of the sensor 100 Liehe medium 10 is prevented from entering the chamber 132, so that the measuring electrode therein 115 at ^¬ least from one the particular substance 30 is potentially shielded aufwei ^¬ send component of the measuring medium 10. For closing and opening the chamber 132 or the chamber opening 133, the device 130 has a cover 134, which can be moved as needed so that the chamber 132 is opened. For this purpose, the cover can be moved with the aid of 134 ent ^¬ speaking devices, folded or removed completely, so that the shield removed and the measurement electrode 115 is exposed so that the surrounding and having a sensor 100 medium 10 comes into contact. In the embodiments of FIGS. 3 and 4, the cover 134 is slidable into and out of a receiving slot 137 of the device 130.

In a variant of the second embodiment, as shown in FIG. 3 and FIG. 4, in addition to the measuring electrode 115 Also, the counter electrode 111 may be disposed in the chamber 160. Thus, would be achievable that the counter electrode 111 can be shielded ge ^¬ jointly with the measuring electrode 115th Alternatively, the counter electrode as in the first exemplary example, can 111th be approximate shape arranged as a flat strip electrode on the outer upper surface 102 of the sensor ^¬ 100th

In a third embodiment according to FIG. 5, the arrangement 1 is designed by way of example as a gastroscope. The Vorrich- tung 130 has an openable and closable lung encapsulation 135, which (not visible in FIG 5) shields the sensor 100 as a whole and not only, as in the two herein are subject ^¬ membered Ausführungeformen, the measuring electrode 115 and possibly the Counter electrode 111. The encapsulation 135 thus has the same function as the covers 131 and 134 described above.

The sensor 100 is located in a space 136 within the encapsulation 135. If necessary, the encapsulation 135 can be opened and thus the shield can be removed, so that the measurement medium 10 can come into contact with the electrode arrangement 110 and in particular with the measurement electrode 115. Likewise, the encapsulation 135 can close again and thus restore the shielding of the measuring electrode 115. Preferably, the third embodiment is applied when the assembly 1 is not formed as endoscopy capsule. In the case of training as a gastroscope 1, for example. As described in WO2010 / 094650A1 described and as shown in FIG 5, a suitable encapsulation can at the Gastroskopspitze 2, where the sensor 100 is arranged to be attached 135, NEN by ei ^¬ opened in a working channel 3 of an insertion tube 5 of the gastroscope 1 guided guide wire 4 and ge ^¬ can be closed. The Figure 5 shows the arrangement with a closed encapsulation, so the sensor 100 in the first mode, the FIG 6 shows the same arrangement with geöff ^¬ neter encapsulation 135, that in the second operating state of the sensor 100th The inspection unit 120 and the evaluation unit 190 may be disposed away from the sensor 100 in the third embodiment. The connection between electrode arrangement 110 and control unit 120 can be realized via the working channel 3.

In each of the three embodiments, the cover 131, 134 or 135 in the closed state, ie in the first operating state of the sensor 100, prevents the measuring medium 10 from reaching the measuring electrode 115. In a typical measurement in these two embodiments, the sensor 100 is first moved to the desired measuring location with the cover 131, 134 or 135 closed. This may, for example, be a specific location in the stomach of a patient. Only there is the cover 131, 134 or 135 opened at the start of measurement, so that the measuring medium 10 located there in the now second operating state of the sensor 100, abruptly in the room 140, 132 and 136 reach and there with the measuring electrode 115 in Can contact. At the same time, the electrical measured variable is monitored with the measuring device 120. In the event that the limited hours ^¬ te substance is in the measured medium 10 30, the reduction of silver chloride layer 117 of the measuring electrode 115. begins This is reflected in a corresponding measurement signal to the meter 120th

Advantageously, the cover 131, 134 and 135 as ^¬ spent in the closed position and thus the Sen ^¬ sor 100 are placed in the second operating state in which it causes a shielding of the measuring electrode 115, so that a previously abolished shield restored becomes. In a specific application of this variant, the sensor 100 is first spent with such a cover positioned 131, 134 and 135 to the measurement location, that a ^trailing shield for the measuring electrode is achieved 115th At the start of measurement, the cover 131, 134 or 135 will be operated to open or to be released and the Abschir ^¬ mung in a first measuring phase in that the measuring medium present at the measuring location 10, possibly including the ammonia, 30, into the space 140, 132 and 136 reach and can contact the measuring electrode 115 in con ^¬ tact. At the same time, the electrical measured variable at the electrode arrangement 110 is monitored by the measuring device 120. After completion of the first measurement phase the cover is moved 131, 134 and 135 in a second measuring phase, back into the original closed position, in which it provides shielding of the measuring electrode 115, and hold it there ge ^¬. In a third measurement phase, which corresponds functionally to the first measurement phase, the cover 131, 134 or 135 is again removed and thus the shielding of the measuring electrode 115 is canceled. At the same time, the electrical measured variable is again monitored by the measuring device 120. Following the third phase of measurement, a fourth measurement phase may follow functionally corresponds to the second measurement phase, that is, the shielding of the measuring electrode 115 is restored, in ^¬ which the cover is moved to the closed posi ^¬ tion 131, 134 and 135 ,

This sequence of measuring phases with alternating shielded and unshielded measurement electrode 115 can be continued accordingly, so that the thus configured Cover B ^¬ ckung 131, 134 and 135, a multiple measurement by the sensor 100 allowed. According to the above nomenclature, the measuring electrode 115 is shielded at even-numbered measuring phases and at

odd-numbered measuring phases not shielded.

It is advantageous for all embodiments if, prior to the beginning of the measurement and before the first measurement phase, ie when the sensor 100 is functionalized, there is a chloride solution in the space 140, 132 or 136 in which the measurement electrode 115 is arranged. This ensures that the measuring electrode 115 has a defined silver chloride layer 117 on its surface at the beginning of the measurement. Also, especially for the first and the second exporting ^¬ approximate shape advantageous if the sensor 100 has as an additional development of the invention in its interior a reservoir 150 for a chloride solution 151, for example. For hydrochloric acid HCl, which is connected to the space 140, 132 and 136 via a Zulei ^¬ tion 152. Preferably, with a closed cover 131, 134 or 135, or during the corresponding measurement phases chloride solution from the reservoir 150 may be in the room 140, 132 and 136 are routed, so that the currency ^¬ rend a previous measurement phase possibly degraded silver ^¬ chloride layer 117 of the measuring electrode 115 builds up again. Since ^¬ with it is achieved that the measuring electrode 115 and thus the sensor 100 for multiple measurements can be used, without the sensor 100 must be removed from the measuring medium 10 in the meantime, since in the meantime, possibly degraded in a measuring phase silver chloride layer 117 subsequently ^¬ ßend in a subsequent measurement phase with shielded measuring electrode 115 can be rebuilt. With this, the sensor 100 can be brought back into a defined initial state between two measurements. In the case of the embodiment of the arrangement 1 according to FIGS. 5 and 6, the reservoir can be arranged outside the sensor and the working channel 3 of the gastroscope 1 serves as the feed line 152 for the chloride solution 151 to the space 136.

In a further variant, the cover 131, 134 or 135 may consist of a layer of a material which is soluble in the measurement medium 10, for example gelatin. As soon as the correspondingly equipped sensor 100 is located in the measuring medium 10, the dissolution process of the layer 131, 134 or 135 begins, so that the sensor 100 only after a certain time, that for the dissolution of the layer 131, 134 and 135, respectively is needed for the measurement is used, since the measuring medium 10 previously did not enter the room 140, 132 and 136 and with the

Measuring electrode 115 can come into contact. Until then, the measuring electrode 115 is thus exposed to no disturbing or harmful influences. In a further variant of the cover 131, 134 or 135 may be formed such by appropriate material ^¬ optionally in all embodiments is that they only for the ammonia 30, or more generally only for the particular sub- punch 30, is impermeable, but no shielding for a chloride solution such as hydrochloric acid HCl and possibly other, non-interfering substances. Thus, it is sufficient ^¬ enough that even with shielded measuring electrode 115, the chloride solution from the measuring medium 10 can reach the measuring electrode 115, so that the silver chloride layer 117 is constructed or, if the layer 117 is already fully built, the silver chloride layer 117 in this constructed state is obtained. Only with abolished shield also the potentially present ammonia 30 reaches the measuring electrode 115 and in turn causes a detectable degradation of the

Silver chloride layer 117.

Advantageously, the monitoring of the electrical measured variable with the measuring device 120 can also be continued during those measuring ^phases during which the space 140, 132 or 136 is closed and the measuring electrode 115 is shielded. As mentioned in the introduction, the electrode arrangement 110 also has a counterelectrode 111 ^adjacent the measuring electrode 115, the electrical measured variable being determined with the aid of these two

Electrodes 111, 115 is monitored or measured. The counterelectrode 111 preferably consists of one of an acid, in particular hydrochloric acid HCl, invariable metal, for example. Of stainless steel, gold, platinum or other suitable noble metal. Alternatively, the counter electrode 111 may also be made of silver. In order to prevent a silver chloride layer from forming on such a silver counterelectrode 111 in this case, the electrode 111 can be set to a corresponding potential by means of the control unit 120.

For the functionalization of the sensor 100 for the detection of HBP-silver sensing electrode 115 may be before the measurement and before the introduction of the sensor 100 in the measuring medium 10 by means of ei ^¬ ner chloride solution, eg. Hydrochloric acid HCl, etched, so at the beginning of the measurement, a silver chloride layer 117 is available on the measuring electrode 115.

The HBP sensor 100 may, for example, be accommodated in an endocapsule as described in WO2009 / 127528A1. In such an embodiment, the above-mentioned sensor body 101 may be the housing of the endocapsule or the endocapsule itself. In another implementation, the HBP sensor 100 may be disposed on the tip of a catheter insertable into a body to be examined. As soon as the catheter tip with the sensor 100 is at the desired measuring position, a mechanism is activated, for example via a cable pull of the catheter, which causes the cover 131, 134 or 135 to be actuated and thus generates the shielding of the measuring electrode 115 or canceled.

Furthermore, the HBP sensor 100 can also be used as in the DE

102013227086 described on the head of a biopsy forceps be angeord ^¬ net. DE 102013227086 describes a biopsy forceps for removing a tissue sample from a cavity of a human or animal body, the biopsy forceps having a head for separating the tissue sample from the cavity and an operating device. Furthermore, the

 Biopsy forceps on the head of an electrode assembly, with the presence of Helicobacter pylori can be detected. The HBP sensor 100 can thus also be designed as such a head of a biopsy forceps. The operating device of the biopsy forceps can then be adapted so that an actuation of the cover 131, 134 and 135 is possible.

Furthermore, the HBP sensor 100 may be attached to a gastroscope as described in WO2010094650A1.

In addition to these embodiments, the inventive HBP sensor 100 with shieldable measuring electrode 115 can also be integrated into other corresponding devices.

Claims

claims 1. An arrangement (1) with a HBP-sensor (100) for checking a measured medium (10) on presence of Helicobacter pylori (20) by verifying the measurement medium (10) on Before ^¬ handensein a particular substance (30) (in the measuring medium 10), wherein the HBP sensor (100) comprises:  - A measuring arrangement (110) with at least one electrical contact (115), wherein the electrical contact (115) comprises silver and wherein for the detection of the particular substance (30) an electrical measured variable is measured on the measuring arrangement (110),  - A closable and / or openable space (140, 132, 136), in which the electrical contact (115) is arranged, and  - A device (130) with which the electrical contact  (115) in a first operating state of the HBP sensor (100) at least one of the certain substance (30) potentially having component of the measuring medium (10) is shielded, so that the component of the measuring medium (10) not from outside the HBP sensor (100) into the space (140, 132, 136) can pass, and with the shield is canceled and thus the component from outside the HBP sensor (100) in the space (140, 132, 136) can pass, so that the electrical contact (115) in a second Operating condition of the sensor at least with the component of the measuring medium (10) is to bring into contact. 2. Arrangement (1) according to claim 1, characterized in that the device (130) for closing and / or opening the space (140, 132, 136) is formed, so that in the first operating state in a closed space (140, 132 , 136) at least may overall long, the component of the measurement medium (10) not from the outside ^¬ (ßerhalb of HBP sensor 100) into the space (140, 132, 136) and so that (in the second operating state at geöff ^¬ NetEm space 140 , 132, 136) at least the component of the measuring ^¬ medium (10) from outside the HBP sensor (100) in the room (140, 132, 136) and can come into contact with the electrical contact (115). 3. Arrangement (1) according to claim 1 or 2, characterized marked, that the device (130) has a movable cover (131, 134, 135), which is arranged in the first operating state of the ^¬ art, that the space (140, 132, 136) is ^{verschlos ¬} sen, so that the measuring medium (10) not from outside the HBP sensor (100 ) in the space (140, 132, 136), and which is movable so that the space (140, 132, 136) by movement of the cover (131, 134, 135) is openable, so that at least the component of Measuring medium (10) into the space (140, 132, 136) and can come into contact with the electrical contact (115). 4. Arrangement (1) according to claim 3, characterized in that the electrical contact (115) on an outer surface (102) of a sensor body (101) of the HBP sensor (100) is placed on ^¬ , wherein the movable cover (131 ) is arranged in such a manner reasonable to act in the first operating state in conjunction ^¬ forms the space (140) with the outer surface (102) of the HBP-sensor (100) in the region of the electrical contact (115) and closes. 5. Arrangement (1) according to claim 3, characterized in that the space (132) is in the interior of a sensor body (102) of the HBP sensor (100) ersteckende chamber (132), in which the electrical contact ( 115), where ^¬ at - the chamber (132) closable by a movable cover (134) and / or openable chamber opening (133) has ^¬,  - The chamber opening (133) in the open state, a connection of the chamber (132) with an environment of the HBP sensor (100), so that in the vicinity of the HBP Sensor (100) located measuring medium (10) through the chamber ^¬ opening (133) into the chamber (132) and there can come into contact with the electrical contact (115), and - The movable cover (134) is arranged such that it ver ^¬ closes the chamber opening (133) in the first operating state and in the second operating state, the chamber opening (133) opens. 6. Arrangement (1) according to one of claims 2 to 5, characterized in that at least before the beginning of the over ^¬ examination of the measuring medium (10) in the space (140, 132, 136) is a chloride solution, which with the electrical Contact (115) is in contact. 7. Arrangement (1) according to one of claims 2 to 6, characterized in that the HBP sensor (100) has a reservoir (150) for a chloride solution (151), wherein the reservoir (150) with the space (140, 132, 136) is connected such that the chloride solution (151) from the reservoir (150) into the space (140, 132, 136) is conductive. 8. Arrangement (1) according to one of claims 2 to 7, characterized in that the HBP sensor (100) before the beginning of Checking the measuring medium (10) is functionalized such that the space (140, 132, 136) is closed and a chloride solution in the space (140, 132, 136) is located. 9. Arrangement (1) according to one of claims 2 to 8, characterized in that the device (130) is adapted to repeatedly open the space (140, 132, 136) and close and the HBP sensor (100) with it several times alternately put into the first and the second operating state. 10. Arrangement (1) according to one of claims 3 to 9, characterized in that the cover (131, 134, 135) consists of a material which - at least impermeable to the particular substance (30) and - at least permeable to a chloride solution. 11. Arrangement (1) according to one of claims 3 to 10, characterized in that the cover (131, 134, 135) consists of a material in which  - at least impermeable to the particular substance (30) and - is soluble in the measuring medium (10). 12. Arrangement (1) according to one of claims 2 to 11, characterized in that the measuring arrangement (110) has at least one further electrical contact (111), wherein the electrical measured variable between the electrical contact (115) and the further electrical Contact (111) is determined, wherein the further electrical contact (111) is also arranged in the space (140, 132, 136), so that the further electrical contact (111) in the second operating state together with the electrical contact ( 115) is shielded. 13. Arrangement (1) according to one of the preceding claims, characterized in that the HBP sensor (100) is functionalized prior to the start of the examination of the measuring medium (10) such that the electrical contact (115) has a defined silver chloride layer on its surface , 14. Arrangement (1) according to one of the preceding claims, wherein the assembly (1) is a catheter, a gastroscope, an endoscopy capsule or a biopsy forceps. 15. Method for checking a measuring medium (10) for the presence of Helicobacter pylori (20) by checking the measuring medium (10) for the presence of a specific substance (30) in the measuring medium (10) with an arrangement (1) according to one of the preceding claims , in which  - The HBP sensor (100) of the arrangement (1) with shielded electrical contact (115) is moved to a first desired location in the measuring medium (10), - The shield of the electrical contact (115) is released at a certain time for a first measurement phase, so that the measuring medium located at the first location (10) can only come in contact with the electrical contact (115) from the desired time, in which  - The electrical parameter is monitored at least in the first measurement phase and is closed from the monitored electrical parameter to a presence of Helicobacter pylori (20) in the measuring medium (10) at the measuring location. 16. The method according to claim 15, characterized in that in a second measurement phase after the first measurement phase, the shielding of the electrical contact (115) is restored, so that at least the component of the measuring medium (10) in the second measurement phase not with the electrical contact (115) can come into contact. 17. The method according to claim 16, characterized in that for a third measurement phase, the shielding of the electrical contact (115) is canceled, so that the measuring medium located at the measuring (10) in the third measuring phase with the electrical contact (115) in contact can occur. 18. The method according to any one of claims 16 to 17, characterized in that the electrical measured variable is also monitored in an even measuring phase. 19. The method according to any one of claims 16 to 18, character- ized in that the HBP sensor (100) in a even measuring phase to a location different from the first location. 20. The method according to any one of claims 16 to 19, characterized in that in an even measuring phase with abge ^¬ shielded electrical contact (115) a chloride solution in the space (140, 132, 136) is passed to a new Silver chloride layer on the surface of the electrical Kon ^¬ takts (115) to form.