Microneedle and method for manufacturing the same

Abstract

The invention relates to a microneedle (10), in particular for transdermal and / or intradermal active ingredient delivery, having a support structure (12) and having at least one needle structure (14) arranged on the support structure (12) for penetrating the keratinocyte layer of human and / or animal skin. The invention is characterized in that at least the needle structure (14) is produced by 3D screen printing. The invention also relates to a microneedle with a drug and a production method using 3D screen printing.

Description

Technical Field

[0001] The present invention relates to a microneedle, in particular for transdermal and / or intradermal active ingredient delivery. Similarly, the present invention relates to a microneedle device, a medical patch and a method for manufacturing a microneedle. Background Art

[0002] Transdermal therapeutic systems or transdermal patches can provide active ingredients to the whole body after penetrating the skin. However, there are active ingredients that cannot be absorbed by the body only by applying them through the skin. In particular, some drugs cannot overcome the main diffusion barrier of the skin, the so-called stratum corneum or corneous cell layer. For this reason, so-called microneedle patches or microarray patches have been developed. Such microneedle patches or microarray patches have a large number of very small needles that penetrate the upper layers of the skin and thus improve drug delivery.

[0003] For the production of microneedles, for example, micromolding processes or lithography processes (soft lithography or drawing lithography) can be used. Another well-known process is the so-called droplet born airblowing method and the electrospinning pillar array process. These processes are only suitable for mass production to a limited extent. In addition, due to the high processing temperatures, there is a risk of material stress. In addition, during the casting process, due to the casting channel structure, the material consumption can be high and thus the active ingredient can also be wasted. Finally, there are also limitations in the choice of carrier materials. Summary of the invention

[0004] In view of the above background, the object of the present invention is to specify a microneedle that can be manufactured in large quantities with limited effort and greater flexibility or wider application possibilities. Similarly, the object of the present invention is to disclose a microneedle device and a medical patch containing such a microneedle. Finally, the object also includes specifying a method for manufacturing such a micropatch.

[0005] Regarding microneedles, this purpose has been solved by the technical solutions defined in the embodiments of the present application. Advantageous implementation schemes are given in the preferred embodiments of the present application.

[0006] The microneedles according to the present invention are particularly suitable for transdermal and / or intradermal active ingredient delivery. Therefore, such microneedles can be used to administer active ingredients through the skin and / or into the skin. This allows greater flexibility in the administration of active ingredients.

[0007] To this end, the microneedle according to the invention has a support structure and at least one needle structure arranged on the support structure for penetrating the keratinocyte layer of human and / or animal skin. According to the invention, at least the needle structure is manufactured by 3D screen printing.

[0008] In particular, the needle structure can be fixedly arranged on the support structure. Thus, the support structure can be designed to hold the needle structure, thereby simplifying the handling of the needle structure for the corresponding active ingredient administration.

[0009] The production of the needle structures by additive manufacturing, in particular 3D screen printing, allows a higher degree of flexibility in terms of the material composition and shape of the needle structures. At the same time, using additive manufacturing, in particular 3D screen printing, a large number of microneedles or needle structures can be easily produced. By using additive manufacturing techniques, in particular 3D screen printing, needle structures with very low material or temperature stresses can also be produced. In this way, restrictions on the choice of materials and / or active ingredients to be processed can be reduced.

[0010] In this context, three-dimensional screen printing is particularly preferably understood as an additive manufacturing process in which a powder-based suspension is transferred to a substrate by means of a doctor blade through a fixed printing mask, in particular a printing screen and / or a printing template, and dried. This step can be repeated several times until the respective desired component height or component shape is achieved. This can produce a screen-printed workpiece.

[0011] In this context, the term screen printing workpiece may preferably be understood as a workpiece that is to be subjected to a drying and / or sintering step or has been subjected to such a step. This applies in particular to workpieces made of metal, ceramic, glass material and / or polymer material. In addition, printed products made of polymeric materials and / or materials containing or consisting of cellulose may be referred to as "three-dimensional screen printing workpieces". In particular, it is also possible to subject a printed workpiece layer made of polymeric material to a sintering step. A screen printing workpiece may also be understood as a workpiece made of a non-sinterable material or without a sintering step.

[0012] In the context of the present invention, a screen-printed workpiece is, in particular, a workpiece which is produced at least partially by three-dimensional screen printing.

[0013] According to a preferred embodiment, the support structure can also be manufactured by 3D screen printing or additive manufacturing. In this way, the production flexibility can be further increased. In this way, the entire microneedle can be provided in large quantities with only a small effort. In addition, in this way, the needle structure and the support structure can be produced using the same material or the same substrate, which can further reduce the production workload. Therefore, the entire microneedle can be manufactured by 3D screen printing or additive manufacturing.

[0014] According to another preferred embodiment, the needle structure and the support structure can be formed as one piece. By forming the needle structure and the support structure as one piece, it can be ensured in particular that the needle structure is arranged on the support structure with a sufficiently high strength, thereby avoiding undesired detachment. Similarly, the needle structure and the support structure can be manufactured by an uninterrupted process sequence. In particular, the needle structure and the support structure can be manufactured by using three-dimensional screen printing in an uninterrupted process sequence. To this end, for example, the support structure can be manufactured from one or more layers, and the needle structure can be applied to the support structure by a further printing sequence. Between the individual printing steps, the printed material can be dried. After the printing sequence, thermal bonding can be performed, for example by using UV light.

[0015] According to another preferred embodiment, the support structure can be generated separately from the needle structure. The needle structure can be arranged and / or attached to the support structure by 3D screen printing. Thus, the needle structure can be applied layer by layer to the separately generated support structure, in particular by layer by layer construction in a 3D screen printing process.

[0016] In particular, the support structure can be generated in a different way relative to the pin structure, i.e. without using additive manufacturing or 3D screen printing. The pin structure can then be applied to this alternatively generated support structure by 3D screen printing and thus connected to the support structure. Depending on the way the support structure is generated, the production effort can be further reduced in this way.

[0017] According to another preferred embodiment, the needle structure can be at least partially cylindrical and / or have a constant and / or circular cross section at least partially along its longitudinal extent. The entire needle structure can also be cylindrical and / or have a constant and / or circular cross section along its longitudinal extent. Such a geometric design can be manufactured by additive manufacturing with only a little effort, which means that the production costs can be reduced, especially for large-scale production.

[0018] The circular cross section can be produced in particular by production steps of limited complexity.The cross-sectional shape remains constant at least partially along its length, for example so that production parameters can be kept constant along the length or when producing a plurality of layers arranged one above the other.

[0019] Other cross-sectional shapes, not just circular or annular cross-sections, can be realized. For example, the needle structure can at least partially have an elliptical, rectangular, in particular square, or triangular, pentagonal or hexagonal cross-section. Such a cross-sectional shape can also be formed at least partially in a constant manner, i.e. in a constant manner in the longitudinal direction or longitudinal extent of the needle structure.

[0020] It may be further advantageous if the needle structure has a varying cross section along its longitudinal extension and / or has different cross-sectional dimensions and / or a constant or varying cross-sectional shape. This can further increase the flexibility of the shaping. Different parts of the needle structure extending along the longitudinal extension can be specifically designed according to functional requirements regarding the external dimensions and the external shaping, for example, regarding the penetration of the keratinocyte layer of human or animal skin, or the application or delivery of the corresponding desired active ingredient into or through the corresponding skin.

[0021] In a particularly preferred manner, the needle structure can be stepped along its longitudinal extension and / or have a constant cross section, in particular a constant cross-sectional shape and / or cross-sectional size, between at least two steps. Through such a design of the needle structure, on the one hand, a change in the longitudinal extension of the needle structure can be achieved, while at the same time the effort to produce a corresponding change can be limited. For example, in this way a relatively small tip area of ​​the needle structure can be produced, through which the various keratinocyte layers can be easily penetrated. At the same time, areas of the needle structure adjacent to the support structure can be created with a greater thickness or a larger outer dimension, respectively, through which a good connection with the support structure can be achieved and better drug delivery can be achieved. Therefore, the use efficiency of the corresponding microneedles can be improved.

[0022] According to another preferred embodiment, the needle structure has, at least partially, a cross-sectional diameter along its longitudinal extension of at least 30 μm, preferably at least 50 μm, preferably at least 70 μm, more preferably at least 80 μm or more than 90 μm, in particular more than 100 μm, even more preferably more than 150 μm, even more preferably more than 200 μm, even more preferably more than 250 μm or more preferably more than 300 μm. This dimensioning of the needle structure dimensions can ensure, on the one hand, sufficient mechanical rigidity in order to ensure that the keratinocyte layer of human and / or animal skin can be penetrated with a high degree of safety. At the same time, this dimensioning can ensure that the active ingredient content in or on the needle structure is sufficiently high.

[0023] According to another preferred embodiment, the needle structure may have a cross-sectional diameter of less than 300 μm, preferably less than 250 μm, preferably less than 200 μm, more preferably less than 150 μm or less than 100 μm or less than 90 μm or less than 80 μm at least partially along its longitudinal extension. This geometric design of the needle structure can ensure that the needle structure penetrates the keratinocyte layer of human and / or animal skin safely and with little or no pain. In particular, a small cross-sectional diameter can be advantageous in the tip region of the needle structure, which is formed at the end of the needle structure, which faces away from the support structure. Penetration of the keratinocyte layer can be easily accomplished using a relatively small cross-sectional diameter.

[0024] In the case of an angular or rectangular cross-sectional shape, the above dimensions may refer to the length of the diagonal. In general, the above dimensions may refer to the maximum possible distance between two points on the periphery of the cross-sectional plane. For example, this may be the length of the diagonal of a rectangular cross section.

[0025] It may be more advantageous if the needle structure has a total length of at least 200 μm, at least 300 μm, at least 400 μm, at least 500 μm, at least 600 μm or at least 700 μm. Such a length dimension can ensure that the needle structure safely penetrates the keratinocyte layer of human and / or animal skin. Similarly, the total length of the needle structure can be less than 1000 μm, less than 900 μm, less than 800 μm, less than 700 μm, less than 600 μm, less than 500 μm or less than 400 μm. This can prevent the needle structure from penetrating too deeply into the corresponding tissue and can also prevent undesirable deformation of the needle structure. By appropriately limiting the length of the needle structure, mechanical stability can be promoted in particular, and in turn, the corresponding desired penetration of the keratinocyte layer can be ensured with high security.

[0026] According to a further preferred embodiment, the needle structure can have at least one longitudinally extending needle structure portion which is located between two steps and has a length of less than 200 μm, less than 150 μm, less than 100 μm or less than 50 μm. By limiting the length of such a needle structure portion, a desired change in the cross-sectional dimensioning or cross-sectional shape can be produced in or along a further needle structure portion.

[0027] According to another preferred embodiment, the needle structure may have at least one needle structure portion extending longitudinally between two steps with a length of at least 20 μm, at least 50 μm, at least 100 μm, at least 150 μm, at least 200 μm or at least 250 μm. Such dimensioning of the needle structure between two adjacent steps enables the needle structure to be produced with relatively little effort. In particular, the cross-sectional shape or cross-sectional dimensioning can be maintained between two adjacent steps so that manufacturing parameters can be maintained to generate the corresponding needle structure portion. For example, when using three-dimensional screen printing, the same printing screen or printing template can be used to generate the corresponding needle structure portion. Therefore, multiple printed layers can be produced by the same printing screen or printing template so that the processing workload in the manufacture of the corresponding needle structure portion can be reduced to a minimum.

[0028] According to another preferred embodiment of the microneedle of the present invention, the needle structure may contain at least one active ingredient or several active ingredients. The active ingredient provided in the needle structure can be released highly safely after penetrating the keratinocyte layer of human and / or animal skin, enter the corresponding organism, and can therefore be used systemically. The needle structure may also be free of active ingredients and is only suitable for perforating the keratinocyte layer of human and animal skin. After the corresponding perforation, the corresponding active ingredient can be applied through the perforated area through a patch.

[0029] In a further preferred embodiment, the needle structure can be designed to deliver the active ingredient by dissolving the material. By dissolving the material, a particularly precise application or dosage of the active ingredient can be ensured. If the corresponding needle structure is designed for complete dissolution of the material, there is no need to subsequently remove the needle structure from the corresponding tissue. Therefore, user-friendliness is improved.

[0030] According to another preferred embodiment, the needle structure can have different active ingredient densities along its longitudinal extension. The needle structure can also have different active ingredients along its longitudinal extension, or provide corresponding active ingredients in different densities or quantities along the longitudinal extension. Therefore, the application of active ingredients to different skin layers can be accurately adjusted or controlled. Therefore, different active ingredients can be applied at different levels or layers of the skin, further improving the function of the microneedles.

[0031] By varying the density of the active ingredient along the length of the needle structure, the temporal profile of the active ingredient administration can also be controlled or adjusted in a suitable manner. Depending on the tissue depth of the active ingredient release, systemic delivery of the corresponding active ingredient can take place at different speeds.

[0032] A variation of the active ingredient or active ingredient density along the length of the needle structure can be achieved with particularly little effort by three-dimensional screen printing. To this end, different layers of the needle structure can be produced by different printing pastes or printing pastes of different compositions. In this way, an active ingredient gradient or an active ingredient variation along the length of the needle structure can be achieved without any effort.

[0033] It may be more advantageous if the needle structure has a coating on which at least one active ingredient for dissolution is formed. Therefore, a needle structure having a needle core and a coating formed thereon may be provided. In this regard, the coating may be formed to dissolve in living tissue, and the core of the needle structure may be retained after the coating dissolves. The core of the needle structure may be created together with the coating of the needle structure by additive manufacturing, in particular 3D screen printing. Similarly, the core of the needle structure may also be formed to dissolve in living tissue, in particular to dissolve in a defined time sequence after the coating.

[0034] In a further preferred embodiment, the needle structure may have a cavity in which at least one active ingredient is arranged. After penetrating the keratinocyte layer of human and / or animal skin, the corresponding active ingredient can be released from the cavity of the needle structure and can therefore be used for the whole body in the corresponding organism. Therefore, the needle structure for active ingredient delivery can be formed by the cavity of the needle structure. The active ingredient can therefore be applied independently of the dissolution of the needle structure or the complete dissolution of the needle structure or the corresponding coating, and can therefore be achieved in a relatively short time.

[0035] It may be more advantageous if the needle structure and / or the support structure are made of polyvinyl pyrrolidone (PVP) or a material containing polyvinyl pyrrolidone (PVP). Generally, the needle structure and / or the support structure may be made of a polymer and / or may be made of a material containing a polymer. The needle structure and / or the support structure may also be generated from a variety of material components and / or material ingredients, such as glycerol, polysorbate 80, trehalose, disodium hydrogen phosphate dodecahydrate, disodium hydrogen phosphate monohydrate and / or distilled water (or generally "pure water") or a solvent. In a further preferred embodiment, the material used to generate the needle structure and / or the support structure may contain a viscosity-increasing component, in particular to improve the processability of the material by additive manufacturing, in particular 3D screen printing.

[0036] In a further preferred embodiment, a material comprising at least one of the following components, in particular as a matrix material, can be used to create the needle-like structure and / or support structure: hyaluronic acid, carboxymethylcellulose, polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVO), PVM / MA copolymer, lactide-glycolide copolymer (PLGA), polylactide (PLA) and / or polyglycolic acid (PGA). The use of these components can further increase the production flexibility and application flexibility of the corresponding microneedles.

[0037] Another aspect of the present invention relates to a microneedle, in particular for transdermal and / or intradermal active ingredient delivery, having a support structure and having at least one needle structure arranged on the support structure, for penetrating the keratinocyte layer of human and / or animal skin, wherein at least the needle structure is produced by additive manufacturing.

[0038] In a preferred manner, the needle structure can be arranged and / or attached to the support structure by additive manufacturing. In particular, the support structure can be generated differently from the needle structure, i.e. without additive manufacturing. The needle structure can then be applied to this alternatively generated support structure by additive manufacturing and thus connected to the support structure. Depending on the way in which the support structure is generated, the manufacturing effort can be further reduced in this way.

[0039] Another aspect of the present invention relates to a microneedle, in particular for transdermal and / or intradermal active ingredient delivery, having a support structure, having at least one needle structure arranged on the support structure, for penetrating the keratinocyte layer of human and / or animal skin, wherein the needle structure has a constant cross-section along its longitudinal extension.

[0040] Another aspect of the present invention relates to a microneedle, in particular for transdermal and / or intradermal active ingredient delivery, having a support structure on which is arranged at least one needle structure for penetrating the keratinocyte layer of human and / or animal skin, wherein the needle structure is stepped along its longitudinal extent.

[0041] Another aspect of the present invention relates to a microneedle, in particular for transdermal and / or intradermal active ingredient delivery, having a support structure and having at least one needle structure arranged on the support structure for penetrating the keratinocyte layer of human and / or animal skin, wherein the needle structure has different active ingredient densities and / or different active ingredients along its longitudinal extent.

[0042] Another aspect of the present invention relates to a microneedle device, in particular for transdermal and / or intradermal active ingredient delivery, comprising a plurality of microneedles as described above. In this case, the microneedles may preferably form a so-called needle array. In this context, a needle array is intended to refer to a regular or irregular arrangement of microneedles along a spatially defined area. For example, a needle array may be circular or rectangular and / or contain a defined number of microneedles.

[0043] According to another preferred embodiment, the support portions of the microneedles may be integrally formed or connected to each other to form an integral support structure. The microneedles may thus have and also maintain a defined arrangement relative to each other in order to improve the manageability and user-friendliness of the microneedle device.

[0044] In a further preferred embodiment, at least two adjacent microneedles of the microneedle device can be spaced apart by at least 100 μm, at least 200 μm, at least 300 μm, at least 350 μm, at least 400 μm, at least 500 μm, at least 600 μm, at least 700 μm, at least 800 μm or at least 1000 μm. Similarly, at least two mutually adjacent needle structures can have a distance of less than 1000 μm, less than 900 μm, less than 800 μm, less than 700 μm, less than 600 μm, at least less than 500 μm or less than 400 μm. The above dimensions can particularly refer to the longitudinal axis or longitudinal center axis of the corresponding needle structure. This geometric arrangement of multiple microneedles can ensure a dense needle arrangement and thus a relatively large delivery of active ingredients on a relatively small skin area. In this way, the user-friendliness of this microneedle device can be further improved.

[0045] Another independent aspect of the present invention relates to a medical patch, in particular for transdermal and / or intradermal active ingredient delivery. Such a patch has a plurality of microneedles as described above and / or a microneedle as described above. In addition, such a patch can be provided with an adhesive means, such as an adhesive tape layer, by which the corresponding microneedles or microneedle devices can be firmly adhered to the skin and ensure safe active ingredient application.

[0046] Another aspect of the present invention relates to a method for manufacturing microneedles, in particular microneedles for transdermal and / or intradermal active ingredient delivery, wherein a support structure is provided and at least one needle structure is produced by 3D screen printing, which is arranged on the support structure for penetrating the keratinocyte layer of human and / or animal skin.

[0047] Another aspect of the present invention relates to a method for producing microneedles, in particular microneedles for transdermal and / or intradermal active ingredient delivery, wherein a support structure is provided and at least one needle structure is manufactured by additive manufacturing, which is arranged on the support structure for penetrating the keratinocyte layer of human and / or animal skin.

[0048] The foregoing details also apply to other independent aspects of the microneedle, the microneedle device, the medical patch, and the method of making a microneedle. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The present invention is explained in more detail below by way of examples with reference to the accompanying drawings.

[0050] A schematic diagram of each case is shown below:

[0051] Figure 1 is a perspective view of a microneedle according to a first embodiment of the present invention,

[0052] Figure 2 is a perspective view of a microneedle according to another embodiment of the present invention,

[0053] Figure 3A is a perspective view of a microneedle according to yet another embodiment of the present invention,

[0054] Figure 3B is based on Figure 3A Longitudinal cross section of the microneedle,

[0055] Figure 4A is a perspective view of a microneedle according to yet another embodiment of the present invention,

[0056] Figure 4B yes Figure 4A The longitudinal cross section of the microneedle shown in

[0057] Figure 5 is a perspective view of a microneedle device according to an embodiment of the present invention, and

[0058] Figure 6 is a perspective view of a medical patch according to one embodiment of the present invention. DETAILED DESCRIPTION

[0059] Figure 1 A microneedle 10 according to an embodiment of the present invention is shown. The microneedle 10 has a support structure 12 and at least one needle structure 14 disposed on the support structure 12 for penetrating the keratinocyte layer of human and / or animal skin. In particular, the needle structure 14 can be sized to penetrate the keratinocyte layer of human and / or animal skin, or can therefore have a suitable geometric shape.

[0060] According to the invention, the needle structure 14 can be manufactured by additive manufacturing, in particular 3D screen printing. To this end, for example, the needle structure 14 can be built up in layers. Between the various steps of layer-by-layer manufacturing, a drying step can be performed to ensure drying of the corresponding previously printed layers.

[0061] The support structure 12 can also be produced by additive manufacturing, in particular 3D screen printing. The pin structure 14 and the support structure 12 can also be formed and / or manufactured in one piece by an uninterrupted process sequence. In particular, both the support structure 12 and the pin structure 14 can be manufactured by 3D screen printing, and for this purpose an uninterrupted process sequence of layer-by-layer construction is used.

[0062] Furthermore, the support structure 12 may be produced separately from the needle structure 14 , and the needle structure 14 may be arranged and / or attached to the support structure 12 by additive manufacturing, in particular 3D screen printing.

[0063] from Figure 1 It can be seen that the needle structure 14 can be at least partially cylindrical or at least partially have a constant and / or circular cross section along its longitudinal extent. In particular, the entire needle structure 14 can be cylindrical or have a uniform and / or circular cross section along its longitudinal extent.

[0064] The needle structure 14 may extend along its longitudinal direction, at least partially, and have a cross-sectional diameter of at least 30 μm, preferably at least 50 μm, preferably at least 70 μm, more preferably at least 80 μm or greater than 90 μm. The needle structure 14 may also have a cross-sectional diameter of greater than 100 μm, even more preferably greater than 150 μm, even more preferably greater than 200 μm, even more preferably greater than 250 μm, even more preferably greater than 300 μm, at least partially, along its longitudinal extent.

[0065] Furthermore, along its longitudinal extension, the needle structure 14 may at least partially have a cross-sectional diameter of less than 300 μm, preferably less than 250 μm, preferably less than 200 μm, more preferably less than 150 μm or less than 100 μm or less than 90 μm or less than 80 μm.

[0066] The needle structure 14 may also have a total length of at least 200 μm, at least 300 μm, at least 400 μm, at least 500 μm, at least 600 μm, at least 700 μm, or less than 1000 μm, less than 900 μm, less than 800 μm, less than 700 μm, less than 600 μm, less than 500 μm, or less than 400 μm. In particular, the length of the needle structure 14 may extend between the support structure 12 and the free end 16 facing away from the support structure 12.

[0067] In accordance with Figure 1 In an embodiment example, the needle structure 14 can have a cross-sectional shape and a cross-sectional size that remain constant along the longitudinal extension. The outer periphery 15 of the needle structure 14 thus remains constant along the longitudinal extension. Such a geometric design can be manufactured by additive manufacturing, in particular by 3D screen printing, with little effort.

[0068] Figure 2 Another embodiment of the microneedle 10 according to the present invention is shown. Figure 2 The microneedle 10 is different from the geometric design of the needle structure 14 in Figure 1 Therefore, Figure 2 The needle structure 14 has a variable cross section along its longitudinal extension. In particular, Figure 2 The needle structure 14 has different cross-sectional dimensions along its longitudinal extent. For this reason, for example, the needle structure 14 can be designed in a stepped manner along its longitudinal extension.

[0069] In accordance with Figure 2 In the example of the embodiment, four steps 18a, 18b, 18c and 18d are provided as examples only. Between the steps 18a and 18b, 18b and 18c, and 18c and 18d, the needle structure 14 can have a constant cross-section or a cross-sectional shape that is continuous along its longitudinal extent. Similarly, the cross-sectional size can have a constant design between two steps 18a and 18b or 18b and 18c or 18c and 18d. Finally, the cross-sectional size and / or the cross-sectional shape can be designed to be constant between the support structure 12 and the step 18a and / or between the step 18d and the free end 16.

[0070] The steps 18a, 18b, 18c and 18d can divide the needle structure 14 into a total of five needle structure parts 20a, 20b, 20c, 20d and 20e. Here, the needle structure part 20a is adjacent to the support structure 12, and the needle structure part 20e forms the free end 16. The cross-sectional shapes of the needle structure parts 20a to 20e can be the same, but the cross-sectional sizes can be different. As the distance from the support structure 12 increases, the corresponding cross-sectional diameters of each of the needle structure parts 20a to 20e may decrease. Therefore, the cross-sectional sizes of the needle structure parts 20a to 20e can gradually decrease starting from the support structure 12.

[0071] The above about Figure 1 The dimensions of the embodiment in the embodiment can also be applied to each of the needle structure parts 20a to 20e. Figure 2 The specification of the total length of the needle structure 14 in may refer to the sum of the individual lengths of the needle structure portions 20a to 20e.

[0072] The needle structure portions 20b, 20c and 20d extending between two steps 18a and 18b, 18b and 18c and 18c and 18d may have a length of less than 200 μm, less than 150 μm, less than 100 μm or less than 50 μm. Such needle structure portions may also have a length of at least 20 μm, at least 50 μm, at least 100 μm, at least 150 μm, at least 200 μm or at least 250 μm. The aforementioned dimensions may further extend to the needle structure portion 20a extending between the support structure 12 and the step 18a. Similarly, the aforementioned dimensions may apply to the needle structure portion 20e extending between the step 18d and the free end 16.

[0073] according to Figure 1 and 2 The needle structure 14 may have at least one active ingredient. Likewise, the needle structure 14 may have different active ingredients. The active ingredient or active ingredient density of the needle structure 14 may be different along the longitudinal extension or vary along the longitudinal extension.

[0074] In addition, according to Figure 1 and Figure 2 The needle structure 14 can be designed to deliver the active ingredient by dissolving the material. In particular, the needle structure 14 can be completely dissolved to deliver the active ingredient. Therefore, it is unnecessary to remove the needle structure 14 after the active ingredient is administered.

[0075] Figure 3A and 3B Another embodiment of the microneedle 10 according to the present invention is shown. Figure 1The embodiment of the present invention is different in that the needle structure 14 has a coating formed to dissolve at least one active ingredient. The coating 22 may be formed on or arranged around the core structure 24. The core structure 24 may also not be designed for dissolution, or may be formed of a dissolution-resistant material different from the material of the coating 22.

[0076] In addition, both the coating 22 and the core structure 24 can be configured to deliver active ingredients by dissolution, wherein the coating 22 contains one or more active ingredients different from the core structure 24, so that a corresponding desired active ingredient delivery profile can be achieved. In the embodiment shown in FIG. 3 , the above-mentioned size specification regarding the cross-sectional diameter can refer to the total cross-sectional diameter formed by the core structure 24 and the coating 22.

[0077] Figure 4A and 4B Another embodiment of a microneedle 10 according to the present invention is shown. Figure 4A and 4B Examples and Figure 1 The embodiment in FIG. 1 differs in that the needle structure 14 has a cavity 26 in which at least one active ingredient is arranged. Figure 4A and 4B The needle structure 12 may be configured to deliver an active ingredient from the cavity 26 of the needle structure 14 .

[0078] The cavity 26 may be a channel extending along the longitudinal extent, which ends at the free end 16 of the needle structure 14. The cavity 26 may further extend into an active ingredient reservoir 28, which is at least partially formed by the support structure 12 or is recessed in the support structure 12. The active ingredient reservoir 28 may also be formed only in the needle structure 14, which is not shown in greater detail here.

[0079] After penetrating the keratinocyte layer of human and / or animal skin, the active ingredient delivery from the cavity 26 to the corresponding organism can be carried out, thereby also enabling the emptying or partial emptying of the active ingredient reservoir 28. In addition, the needle structure 14 may be designed to resist dissolution in a living organism. Similarly, the needle structure 14 according to FIG. 4 may also be designed to deliver active ingredients by dissolution. In this case, the dissolution of the needle structure 14 can occur after the active ingredient is delivered from the cavity 26, so that, for example, different active ingredients can be released continuously in time into the corresponding organism.

[0080] Figure 5 A microneedle device 30 according to an embodiment of the present invention is shown. The microneedle device 30 includes a Figure 1 Similarly, the microneedle device 30 can be composed of Figure 2 The microneedle 10 of any further embodiment shown in Fig. 4 is formed. It is not shown in detail here.

[0081] according to Figure 5 , the individual microneedles 10 are arranged in the microneedle device 30 in a specific arrangement relative to each other, or form a predefined or also random arrangement pattern. In this case, the support structures 12 of the microneedles 10 can be connected to each other or formed integrally. Thus, the support structures 12 of the microneedles 10 can form an overall support structure 32, to which the individual needle structures 12 are arranged or attached.

[0082] The needle structures 12 of the individual microneedles 10 may have a defined distance from each other. Purely by way of example, the spacing of the needle structures 12 of two directly adjacent microneedles 10 may be greater than 300 μm or less than 500 μm, and purely by way of example, the spacing is about 350 μm. Depending on the specific application, the number of individual microneedles 10 of the microneedle device 30 may be changed or selected as desired. The microneedles 10 of the microneedle device 30 thus form a needle array 34.

[0083] Figure 6 A medical patch 36 is shown. Such a medical patch 36 may include a microneedle device 30 or a plurality of microneedles 10. The microneedle device 30 or the microneedles 10 may be arranged or attached to an adhesive tape 38 or medical tape material. The adhesive tape 38 is particularly suitable for adhering to human or animal skin, thereby ensuring highly safe delivery of active ingredients through the microneedles 10 over a period of time.

[0084] Reference numerals list

[0085] 10. Microneedling

[0086] 12 Support structure

[0087] 14-pin structure

[0088] 15 Periphery

[0089] 16 Free end

[0090] 18a-18d stairs

[0091] 20a-20e Needle structure

[0092] 22 Coating

[0093] 24 core structure

[0094] 26 Cavity

[0095] 28 Active ingredient reservoir

[0096] 30 Microneedle Device

[0097] 32 Overall support structure

[0098] 34-pin array

[0099] 36 Medical plaster

[0100] 38 Adhesive tape

Claims

1. A method for manufacturing a microneedle (10) for transdermal and / or intradermal active ingredient delivery, wherein a support structure (12) is provided and wherein at least one needle structure (14) and the support structure (12) are manufactured layer by layer by 3D screen printing, the needle structure (14) being arranged on the support structure (12) for penetrating the keratinocyte layer of human and / or animal skin, wherein between the individual steps for layer by layer manufacturing the support structure (12) and the needle structure (14), a drying step is performed, the drying step ensuring drying of the corresponding previously printed layers, and wherein the needle structure (14) and the support structure (12) are integrally formed and manufactured by an uninterrupted process sequence.

2. The method according to claim 1, characterized in that The needle structure (14) is formed at least partially cylindrical and / or with an at least partially constant and / or circular cross section along its longitudinal extent.

3. The method according to claim 1, characterized in that The entire needle structure (14) is formed cylindrically and / or has a constant and / or circular cross section along its longitudinal extension.

4. The method according to claim 1, characterized in that: The needle structure (14) is formed to have a varying cross section along its longitudinal extension.

5. The method according to claim 1, characterized in that The needle structure (14) is formed to have different cross-sectional dimensions and / or a constant cross-sectional shape along its longitudinal extension.

6. The method according to claim 1, characterized in that The needle structure (14) is formed to extend in a step-like shape along its longitudinal direction.

7. The method according to claim 6, characterized in that The needle structure (14) is formed to have a constant cross-section between at least two steps (18).

8. The method according to claim 6, characterized in that The needle structure (14) is formed to have a constant cross-sectional shape and / or cross-sectional size between at least two steps (18).

9. The method according to claim 1, characterized in that: The needle structure (14) is formed to have a cross-sectional diameter of at least 30 μm at least partially along its longitudinal extension.

10. The method according to claim 1, characterized in that The needle structure (14) is formed to have a cross-sectional diameter of at least 50 μm at least partially along its longitudinal extension.

11. The method according to claim 1, characterized in that: The needle structure (14) is formed to have a cross-sectional diameter exceeding 300 μm at least partially along its longitudinal extension.

12. The method according to claim 1, characterized in that The needle structure (14) is formed to have a cross-sectional diameter of less than 300 μm at least partially along its longitudinal extension.

13. The method according to claim 1, characterized in that The needle structure (14) is formed to have a cross-sectional diameter of less than 200 μm at least partially along its longitudinal extension.

14. The method according to claim 1, characterized in that The needle structure (14) is formed to have a cross-sectional diameter of less than 80 μm at least partially along its longitudinal extension.

15. The method according to claim 1, characterized in that The needle structure (14) is formed with a total length of at least 200 μm, at least 300 μm, at least 400 μm, at least 500 μm, at least 600 μm, at least 700 μm, or less than 1000 μm, less than 900 μm, less than 800 μm, less than 700 μm, less than 600 μm, less than 500 μm, or less than 400 μm.

16. The method according to claim 1, characterized in that The needle structure (14) is formed with a length extending between the support structure (12) and a free end (16) facing away from the support structure (12).

17. The method according to claim 1, characterized in that The needle structure (14) is formed with at least one needle structure portion (20) which extends longitudinally between two steps (18) and has a length of less than 200 μm, less than 150 μm, less than 100 μm or less than 50 μm.

18. The method according to claim 1, characterized in that The needle structure (14) is formed with at least one needle structure portion (20) which extends longitudinally between two steps (18) and has a length of at least 20 μm, at least 50 μm, at least 100 μm, at least 150 μm, at least 200 μm or at least 250 μm.

19. The method according to claim 1, characterized in that The needle structure (14) is configured to include at least one active ingredient.

20. The method according to claim 1, characterized in that The needle structure (14) is configured to include a plurality of active ingredients.

21. The method according to claim 1, characterized in that The needle structure (14) is configured to have different active ingredient densities along its longitudinal extension.

22. The method according to claim 1, characterized in that The needle structure (14) is configured to have different active ingredients along its longitudinal extension.

23. The method according to claim 1, characterized in that The needle structure (14) is designed to deliver the active ingredient by dissolution of the material.

24. The method according to claim 1, characterized in that The needle structure (14) is configured to have a coating (22) formed for dissolution, the coating having at least one active ingredient.

25. The method according to claim 1, characterized in that The needle structure (14) is formed with a cavity (26) in which at least one active ingredient is disposed and / or the needle structure (14) is configured for delivering the active ingredient from the cavity (26) of the needle structure (14).

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