Device for guiding plasma-jet-generated species

Abstract

The invention relates to a device for attaching to a plasma source with a housing delimiting a space between a plasma source and the housing. The housing has an outlet opening and an inlet opening. A sealing element is arranged around the inlet opening on which the plasma source is attached. The sealing element closes the space between the plasma source and the inlet opening. There is an applicator on the outlet opening of the housing. An applicator tube is secured at the proximal end of the applicator, which is fluidically connected to the outlet opening of the housing.

Description

DEVICE FOR GUIDING PUASMASTRAHUERZEUGTER SPECIES

[0001] The present invention relates to a device for guiding plasma-jet generated species directly to a treatment site. STATE OF THE ART

[0002] Plasma sources for medical applications are finding increasing use, both in human and veterinary medicine.

[0003] A plasma is a gas containing free electrons, radicals, ions, and neutral particles. Depending on the type of working gas, the plasma generates reactive species, such as reactive oxygen species like ozone (O3). Reactive species can have antimicrobial effects. Therefore, plasma treatment can support wound healing.

[0004] In the current state of the art, various technologies are used to generate medically effective plasmas. A fundamental distinction can be made between dielectrically hindered discharges (DBE) and jet plasmas.

[0005] A dielectrically hindered discharge (DBE) is generated by applying a high voltage between two electrodes, at least one of which is insulated by a dielectric. This insulation prevents the formation of an arc discharge. Instead, many fine plasma filaments typically form between the electrodes. DBEs can be generated at both low and atmospheric pressures, although their special properties are most pronounced at atmospheric pressure. A DBE can therefore be a non-thermal "cold" plasma, in which the electrons are at a high temperature, while the neutral gas and ions are at approximately room temperature.

[0006] In jet plasmas, a plasma can be generated in a discharge chamber within an electromagnetic field. This plasma is then transported out of the device, particularly the discharge chamber, in the form of a plasma beam or jet, accompanied by a gas stream. The application of such jet plasmas is described in the applicant's patent specification "DE 102006". The type described in documents 019 664 Al and EP 2 462 785 Bl is described therein. A handheld RF plasma nozzle is described in which, due to its special design, a separate RF matching network in the form of a matchbox is not required. This makes it possible to realize a handheld RF plasma nozzle as a handheld plasma device that can be operated manually. During plasma treatment using a handheld plasma device, reactive species (radicals) and radiation (VUV / UV) are generated, which are important for the treatment effect. Furthermore, the plasma is heated by loss processes, and the temperature at the peak is approximately 50°C, which is considered "cold" under plasma conditions.

[0007] In cases where the surface being treated is not the counter electrode, dielectrically hindered discharge (DBE) is relatively insensitive to uneven surfaces, but is limited by the available high voltages to material thicknesses on the order of a few centimeters. Therefore, DBEs are often placed directly on the surface, frequently using it as the counter electrode. Jet plasmas, on the other hand, can generally be effective without direct contact with the surface. The advantage of jet plasmas over DBEs thus lies in their pronounced independence from surface geometry. Furthermore, unlike DBEs, jet plasmas are crevice-penetrating, meaning they can also be effective directly in crevices without necessarily generating a saturated plasma atmosphere, as is the case with DBEs.

[0008] The disadvantage of both technologies is that they are both surface-based, meaning the surface or depression must be directly accessible. Hidden or excessively deep treatment areas cannot be treated without specific intervention, such as exposing the treatment area. TASK OF INVENTION

[0009] The present invention therefore aims to create a device for mounting on a plasma source that enables plasma treatment for previously difficult-to-access treatment areas. SOLUTION TO THE TASK

[0010] This problem is solved according to the invention by the features of the independent claim. Advantageous embodiments are the subject of the dependent claims and the following description.

[0011] The solution consists of positioning the device over a plasma source in such a way that it captures the reactive species or plasma-processed gas generated by a plasma beam and directs it to the treatment site via an applicator tube.

[0012] The invention can be advantageous for plasma treatment in hard-to-reach treatment areas in both veterinary and human medicine.

[0013] An inventive device for mounting on a plasma source comprises a housing that defines a space between the plasma source and the housing. The housing includes an outlet opening and an inlet opening. The inlet opening includes a sealing element configured to close the space between the plasma source and the inlet opening. The inlet opening of the housing is designed to fit onto a plasma source. The species generated by the plasma source, or the plasma-processed gas, can thus enter the space between the plasma source and the inlet opening. The housing further comprises an applicator with a proximal end. The proximal end of the applicator includes an applicator tube that is fluidly connected to the outlet opening of the housing.

[0014] The advantage of the device according to the invention is that the space between the plasma source and the inlet opening of the housing is sealed by means of a sealing element, thus guiding the plasma-processed gas or the species generated by the plasma source through the conically tapered outlet opening of the housing, via the applicator and the applicator tube, to the treatment site. The conically tapered outlet opening enables the axially symmetrical focusing of the plasma-processed gas or the species generated by the plasma source before entering the applicator and the applicator tube. The sealing element minimizes the escape of the plasma-processed gas or the species generated by the plasma source between the plasma source and the inlet opening of the housing. Furthermore, the sealing element prevents the housing of the device from due to back pressure caused by the bundling of the plasma-processed gas or the species generated by the plasma source before entering the applicator, it slips from the plasma source.

[0015] The plasma source can be a device for generating a cold plasma jet. Preferably, the plasma source is a handheld plasma device as described in the applicant's patent specifications "DE 10 2006 019 664 Al" and "EP 2 462 785 Bl".

[0016] The sealing element can be a sealing ring.

[0017] The applicator tube can be detachably attached to the applicator. The proximal end of the applicator can include a plug connection suitable for connecting the applicator to the applicator tube. The plug connection can be a Luer-lock fitting, which is known from the prior art.

[0018] The applicator tube is configured to deliver the reactive species generated by the plasma source to the treatment site. This configuration allows for the treatment of deep or obscured areas. The applicator tube can be a hose or a catheter.

[0019] The problem of reaching difficult-to-access treatment areas is also solved by a device according to the invention that does not include the sealing element described above between the housing and the plasma source. In other words, the sealing element is optional and can be omitted.

[0020] If the sealing element is omitted, a seal between the housing and the plasma source can be achieved by other means.

[0021] For example, the fit between the housing and the plasma source can be chosen to ensure a seal between the plasma source and the housing. For instance, the housing placed on the plasma source can enclose it like a tightly fitting jacket.

[0022] The fit can be chosen, for example, such that the housing deforms plastically when placed on the plasma source, thereby creating a tight connection. The housing and plasma source are ensured. A (strong) elastic deformation of the housing is also conceivable in this context, instead of plastic deformation.

[0023] Alternatively or additionally, the overlap length of the housing with the plasma source can be chosen to be large enough to achieve sufficient sealing of the space inside the housing.

[0024] Alternatively or additionally, the housing can be made entirely or partially from a sealing material, such as an elastomer, so that a separate, i.e., independent sealing element is not required.

[0025] Alternatively or additionally, the plasma source can also include a sealing material, such as an elastomer, on its outer wall, thereby ensuring a seal of the space in the housing.

[0026] Even if the device according to the invention does not include the sealing element, it is suitable to solve the problem by directing the reactive species to the treatment site by means of the applicator tube.

[0027] Preferably, the applicator tube is connected to the housing by means of the applicator tube fixation. Even more preferably, the applicator tube fixation serves to detachably connect the applicator tube to the housing.

[0028] The applicator tube fixation can be, for example, a simple plug connection, a simple screw connection or a Luer connection, as described above.

[0029] In this type of push-fit connection, the detachable connection between the applicator tube and the housing is ensured by friction. For the push-fit connections described here, optional means to reinforce the frictional connection are also conceivable. Such means could be rough surfaces or knurling.

[0030] The screw connection preferably features an internal thread on the applicator tube fixing, which engages with an external thread on the applicator tube in a releasable manner. However, a reverse arrangement of internal and external threads is also possible.

[0031] The Luer connection is a standardized connection and therefore allows the use of existing and / or different (standardized) cannulas, which increases the flexibility of the device's application and reduces costs. The Luer connection can be, for example, a so-called Luer-Slip connection (without threads) or a so-called Luer-Lock connection (with threads).

[0032] In a preferred embodiment, an adapter is provided between the applicator tube fixing and the applicator tube. The adapter allows otherwise incompatible connecting elements of the applicator tube fixing and the applicator tube to engage with each other, preferably in a detachable manner. The adapter can serve to establish a standardized connection between a non-standardized applicator tube fixing and a standardized applicator tube (or vice versa).

[0033] If, for example, the applicator tube fixing has a thread and the applicator tube has a push-fit connection, an adapter with a complementary thread or push-fit connection can be used for the preferably detachable mounting of the applicator tube to the device housing. This increases the flexibility and expands the range of applications for the device, as it can be operated with different applicator tubes without replacing any parts, simply by using the adapter.

[0034] If, for example, the applicator tube fixing has a simple thread and the applicator tube has a Luer-lock connection, an adapter with a complementary simple thread or Luer-lock connection can be used for the detachable mounting of the applicator tube to the device housing. This allows the device to be used with standardized applicator tubes, offering logistical and cost advantages.

[0035] If, for example, the applicator tube fixing has a simple thread and the applicator tube has a Luer-slip connection, an adapter with a complementary simple thread or a complementary Luer-lock connection can be used for the detachable mounting of the applicator tube to the device housing. This allows the device to be used with standardized applicator tubes, offering logistical and cost advantages.

[0036] The applicator tube can be a standardized (mass-produced) item. It can be reusable or intended for single use as a disposable item.

[0037] The applicator tube can be, for example, an infusion tube, a cannula, or any other (medical) attachment, such as an ear attachment. Examples of implementation: The invention is explained in detail with the following drawings shown in the figures. Fig. 1 shows a schematic section through the device according to the invention. Fig. 2 shows a schematic section through another embodiment of the device according to the invention. Fig. 3 shows various inventive variants of the applicator tube fixation and of applicator tubes in a disassembled state. Fig. 4 shows the variants of the applicator tube fixing and applicator tubes shown in Fig. 3 according to the invention in an assembled state. Fig. 5 shows another example of a detachable connection between the applicator tube and the housing. Fig. 6 shows yet another example of a detachable connection between applicator tube and housing, along with another variant of the applicator tube. The following reference symbols are used to identify the individual elements of the device's structure: Reference symbol list: Fig. 1 shows by way of example the basic structure of the device according to the invention which is mounted on a plasma beam or plasma jet source 5. The plasma source 5 generates a plasma jet or effluent 7, which in turn generates reactive species 6. Because the plasma source 5 is operated with a process gas and the space between the plasma source 5 and the housing 3 is sealed by an optional sealing element 4, the plasma-processed gas is guided through the conically tapered outlet opening of the housing 3, over the applicator and the applicator tube 1, and preferably the applicator tube fixing 2, to the treatment site. The applicator tube fixing 2 can be detachably mounted to the housing 3, for example, by means of a thread (not shown). In the arrangement shown, an external thread on the applicator tube fixing 2 would engage with an internal thread in the housing 3. A connection using an external thread on the housing 3 and an internal thread on the applicator tube fixing 2 is also conceivable. The detachable connection allows for easy replacement of the applicator tube fixing 2 if it is defective or needs to be replaced by a different applicator tube fixing 2 that offers a different type of connection to the applicator tube 1. The applicator tube fixing 2 can also be connected to the housing, preferably detachably, by means of a simple plug connection (as shown in Fig. 1). However, a virtually non-detachable plug connection using a press or shrink fit can also be provided. This type of connection is permanent and avoids the use of failure-prone joining methods and joints that may deteriorate over time. The applicator tube fixing 2 can also be permanently connected to the housing, for example by means of an adhesive bond or a (plastic) welding connection. The non-removable connection between applicator tube fixing 2 and housing 3 can preferably ensure a better seal than a removable connection. In the embodiment shown in Fig. 1, the applicator tube 1 and housing 3 are detachably mounted by means of a simple plug connection. The applicator tube 1 is inserted into the applicator tube holder 2 and is held in place by friction. Alternatively, the applicator tube 1 could also be attached to the applicator tube holder 2 from the outside. The embodiment shown in Fig. 2 differs from the device shown in Fig. 1 in the type of connection between applicator tube 1 and housing 3. The connection between applicator tube fixation 2 and housing 3 can be the same as described in connection with Fig. 1. In the illustrated embodiment, the connection between applicator tube fixation 2 and applicator tube 1 is made by means of an adapter 8. The adapter 8 is positioned between applicator tube fixation 2 and applicator tube 1. This allows a Luer-lock connection to be established between applicator tube 1 and applicator tube fixation 2. In this way, the device can be used with applicator tubes commonly used in medical applications, such as infusion tubing or cannulas. Instead of the simple threaded connection shown between applicator tube fixing 2 and adapter 8, a plug connection would be conceivable in this case, for example. Additionally, the plug connection could be supplemented by a positive locking component, in which a projection on the adapter 8 engages in recesses in the applicator tube fixing 2. Such a plug connection with positive locking would be similar in the sectional view to the simple thread shown. A reversed arrangement of internal and external threads (or projections / steps and grooves) on the applicator tube fixing 2 and on the adapter 8 is also possible. Fig. 3 shows three examples of applicator tubes 1, each of which can be mounted differently on the housing 3 of the device. In the upper part of Fig. 3, the applicator tube 1 is an infusion tube with a Luer-lock connection. The applicator tube fixation 2 has a complementary Luer-lock connection, so that the infusion tube can be mounted directly onto the applicator tube fixation 2. In the central part of Fig. 3, the applicator tube 1 is a cannula. In the example shown, the cannula is detachably connected to the applicator tube fixation 2 via a simple push-fit connection. In the lower part of Fig. 3, the applicator tube 1 is a snap-on ear tip. The applicator tube holder 2 has a simple internal thread. In this example, the ear tip cannot be attached to the applicator tube holder 2. Therefore, an adapter 8 is used. This adapter has an external thread on one side that is compatible with the internal thread of the applicator tube holder 2. The ear tip can be attached to the other side, or end, of the adapter 8. To increase the frictional connection between the adapter 8 and the ear tip, the adapter 8 has annular serrations at the end onto which the ear tip is to be attached. In all three parts of Fig. 3, a sealing element, exemplified as an O-ring, is provided on the applicator tube fixing 2 to seal the connection to the applicator tube 1 or to the adapter 8. Figure 4 shows exemplary embodiments of the device shown in Figure 3 in an assembled state. In particular, the intermediate adapter 8, which is arranged between the ear attachment and the applicator tube fixation 2, is visible in the lower part of Figure 4. In contrast, in the upper or middle part of Figure 4, the applicator tube fixation 2 and the infusion tubing or cannula are directly connected to each other without an intermediate adapter. Figure 5 shows another embodiment in an assembled state. In this exemplary embodiment, an applicator tube 1 is connected to an adapter 8 via a Luer-lock connection, which in turn is connected to an applicator tube fixation 2. Figure 6 shows another embodiment in an almost assembled state. Here, an applicator tube 1 consisting of several parts is almost completely screwed into the applicator tube fixation 2 of a housing 3 via a Luer-lock connection. The proximal part of the applicator tube 1 is an infusion tube. The distal part of the applicator tube 1 is connected to the infusion tube via an adapter onto which it is pushed. Such combinations of compound applicator tubes 1, which can be mounted to the applicator tube fixation 2 and thus to the housing 3 in different ways, increase the flexibility of the device according to the invention and enable the reaching of treatment locations that are difficult to access.

Claims

PATENT CLAIMS 1. Device for mounting on a plasma source, comprising a housing (3) which defines a space between a plasma source (5) and the housing (3), wherein the housing (3) comprises an outlet opening and an inlet opening, and wherein a sealing element is provided around the inlet opening on which the plasma source (5) is mounted. (4) is arranged to be configured to close off the space between the plasma source (5) and the inlet opening (3); and an applicator having a proximal end, the proximal end of the applicator comprising an applicator tube (1) and being fluidly connected to the outlet opening of the housing (3).

2. Device according to claim 1, wherein the plasma source (5) is a device for generating a cold plasma jet, preferably wherein the device is a handheld plasma device.

3. Device according to claim 1 or 2, wherein the sealing element (4) is preferably a sealing ring.

4. Device according to claims 1-3, wherein the applicator tube (1) is detachably attached to the applicator.

5. Device according to claims 1-4, wherein the proximal end of the applicator comprises an applicator tube fixation (2) suitable for connecting to the applicator tube (1).

6. Device according to claim 5, wherein the applicator tube fixation (2) is preferably a Luer-Lock connection.

7. Device according to claim 5 or 6, wherein the applicator tube (1) is connected to the applicator tube fixing (2) by means of an adapter (8), and is preferably detachably connected.

8. Device according to claims 1-7, wherein the applicator tube (1) is suitable for directing the reactive species (6) generated by the plasma source (5) to the treatment site.

9. Device according to claim 8, wherein the applicator tube (1) is configured to achieve deep or hidden treatment sites.

10. Device according to claims 1-9, wherein the applicator tube (1) is a hose, a cannula or a catheter.

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