Microneedle applicator

Abstract

This invention provides a microneedle applicator that is miniaturized and lightweight with a simple configuration and a small number of parts, offers excellent mass-producibility, allows for easy and proper microneedle puncture, provides user satisfaction, and delivers sufficient drug delivery effects, all while being highly operable. [Solution] The microneedle applicator 10 comprises an applicator body 13, a sliding body 14 slidably held inside the applicator body, a biasing means 15 housed inside the applicator body that biases the sliding body toward the front of the applicator body, and a pickup tool 17 detachably connected to the front of the sliding body. During use, the microneedle array 12, detachably held at the tip of the pickup tool and protruding from the front of the applicator body, is pressed against the surface of the skin 11 and moves toward the base of the applicator body against the biasing force of the biasing means.

Description

Technical Field

[0001] The present invention relates to a microneedle applicator for use when administering medication into the body using a microneedle array instead of conventionally used syringes for medical or cosmetic purposes.

Background Art

[0002] In the future, as the declining birthrate and aging population progress, the role played by medical care will increase, which is expected to lead to a shortage of hospitals, physicians and other medical personnel. Medical practices include medication therapy in addition to surgical treatment, and among medication therapies, intrabodily administration via syringes accounts for a large proportion. Such administration via syringes is normally performed at hospitals by qualified personnel such as physicians and nurses, but some types of administration, such as insulin administration for diabetes, are permitted to be performed by patients themselves at home. Accordingly, if home medication administration based on a physician's prescription can be popularized, the frequency of patients' hospital visits can be reduced, and the burden on physicians and patients (especially the elderly and working people) can be alleviated. For this reason, interest in such home medication administration is growing. In particular, in depopulated areas facing the problems of hospital and physician shortages, demand for home medication administration is large.

[0003] However, while medication administration via syringes has the advantage of enabling direct administration into subcutaneous tissue or blood vessels, it has the drawbacks of being painful and causing skin damage or swelling as the number of administrations increases. Accordingly, the use of a resin microneedle array having a plurality of sharp-tipped microneedles on a flat plate instead of syringes has been proposed. The features of this microneedle array are that, since the microneedles have a length capable of reaching the pain-free depth in subcutaneous tissue, painless medication administration can be performed, and patients can easily perform self-administration simply by applying the array as a patch to the epidermis, so that the burden on patients can be greatly reduced. Such microneedle arrays are expected to be used not only for medical purposes but also for cosmetic purposes. For the reasons described above, various studies have been conducted on applicators used to press microneedle arrays against the skin, with the aim of promoting the widespread use of microneedle arrays. For example, Patent Documents 1 and 2 disclose applicators that press a microneedle array (microneedle device) against the skin by pressing a cylindrical member and an operating button with a finger, thereby moving a plunger and piston toward the front of the applicator against the force of a spring. However, such applicators require considerable force to operate, which presents a problem for women, the elderly, and others who may find them difficult to use. To solve this problem, Patent Document 3, filed by the applicant of the present application, discloses a vibrating applicator for microneedles, in which a head containing a vibrator is attached to the front of the applicator body, and the vibrator is driven to vibrate the microneedle array attached to the tip of the head while it is pressed against the skin. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2018-191702 [Patent Document 2] Japanese Patent Publication No. 2018-102680 [Patent Document 3] Japanese Patent Publication No. 2023-94161 [Overview of the project] [Problems that the invention aims to solve]

[0005] The applicator described in Patent Document 3 can drive a vibrator simply by pressing a switch, thereby vibrating a microneedle array pressed against the skin. This reduces the effort required, making it easy to use even for women and the elderly who may have less strength, and it offers excellent operability. However, it requires a power supply, switch, and wiring to drive the vibrator, resulting in a large number of parts, a complex configuration, reduced mass production capabilities, and an increase in the size of the applicator. On the other hand, if the pressure (pressure force) of cosmetic microneedles is too high, it may damage the skin and cause redness. However, if the pressure is too low, the sensation of using the microneedles may be insufficient, and users may not be satisfied. Therefore, it is necessary to properly manage the pressure of the microneedles (applicators), but there is a problem in that the pain and comfort felt by users vary from person to person, making it difficult to standardize the pressure.

[0006] This invention has been made in view of the above circumstances, and aims to provide a microneedle applicator with a small number of parts, a simple structure, miniaturization and weight reduction, excellent mass-producibility, easy and proper microneedle puncture, user satisfaction, and excellent operability for achieving sufficient drug delivery effects. [Means for solving the problem]

[0007] A microneedle applicator according to the present invention, which is used to press a microneedle array onto the surface of the target skin, is a microneedle applicator used for the above purpose, The applicator comprises an applicator body, a sliding body slidably held inside the applicator body, a biasing means housed inside the applicator body that biases the sliding body toward the front end of the applicator body, and a pickup tool detachably connected to the front end of the sliding body. During use, the microneedle array, detachably held at the tip of the pickup tool and protruding from the front end of the applicator body, moves toward the base end of the applicator body against the biasing force of the biasing means while pressed against the surface of the skin.

[0008] Here, by changing the pickup tool according to the size or shape of the substrate portion of the microneedle array, a single microneedle applicator can be used to handle various types of microneedle arrays.

[0009] In the microneedle applicator according to the present invention, it is preferable that the applicator body has a pressure guide, and during use, the leading end face of the pressure guide comes into contact with the surface of the skin, thereby limiting the amount of movement of the microneedle array, and so that the microneedle array is pressed against the surface of the skin with a pressure of less than or equal to a set upper limit.

[0010] In the microneedle applicator according to the present invention, it is preferable that the set upper limit of the pressing force can be changed by adjusting the initial protrusion amount of the microneedle array protruding from the front of the applicator body and / or the biasing force of the biasing means.

[0011] In the microneedle applicator according to the present invention, it is preferable that the initial protrusion amount of the microneedle array can be adjusted by changing the axial length of the pickup tool.

[0012] In the microneedle applicator according to the present invention, it is preferable that the pickup tool is held by the sliding body by magnetic force.

[0013] In the microneedle applicator according to the present invention, it is preferable that a fitting recess is formed on the tip side of the sliding body, and a fitting projection that can be inserted into and removed from the fitting recess of the sliding body is formed on the base side of the pickup tool. [Effects of the Invention]

[0014] The microneedle applicator according to the present invention moves a pickup tool holding a microneedle array together with a sliding body against the biasing force of a biasing means, thereby pressing the microneedle array against the skin surface with a predetermined pressing force. Despite its simple configuration, it can provide the user with satisfaction and an appropriate drug delivery effect.

[0015] In the microneedle applicator according to the present invention, the applicator body has a pressure guide, and when in use, the leading end face of the pressure guide comes into contact with the surface of the skin, thereby limiting the amount of movement of the microneedle array. As a result, when the microneedle array is pressed against the surface of the skin with a pressure below a set upper limit, it is possible to prevent the skin from becoming overloaded and to perform microneedle puncture properly.

[0016] In the microneedle applicator according to the present invention, if the upper limit of the setting of the pressing force can be changed by adjusting the initial protrusion amount of the microneedle array protruding from the tip of the applicator body and / or the biasing force of the biasing means, then medication can be administered with an appropriate pressing force according to the user's preference, the purpose of treatment, or the type of microneedle or drug.

[0017] In the microneedle applicator according to the present invention, if the initial protrusion amount of the microneedle array can be adjusted by changing the axial length of the pickup tool, then by preparing multiple pickup tools with different axial lengths in advance, the initial protrusion amount of the microneedle array can be easily adjusted and the pressing force changed simply by changing the pickup tool.

[0018] In the microneedle applicator according to the present invention, when the pickup tool is held on the sliding body by magnetic force, the pickup tool can be replaced easily.

[0019] In the microneedle applicator according to the present invention, when a fitting recess is formed on the distal side of the sliding body, and a fitting projection that can be inserted into and removed from the fitting recess of the sliding body is formed on the proximal side of the pickup tool, positional displacement and inclination of the pickup tool can be prevented, and the microneedle can be reliably pressed against a predetermined position of the skin. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] [Figure 1] It is a fragmentary cross-sectional front view showing the structure of a microneedle applicator according to an embodiment of the present invention. [Figure 2] It is a fragmentary cross-sectional front view showing the usage state of the same microneedle applicator. MODES FOR CARRYING OUT THE INVENTION

[0021] Next, embodiments embodying the present invention will be described with reference to the accompanying drawings. A microneedle applicator 10 (hereinafter simply referred to as applicator 10) according to an embodiment of the present invention shown in FIG. 1 and FIG. 2 is used when pressing a microneedle array 12 against the surface of the skin 11 of a target patient or the like. As shown in Figures 1 and 2, the applicator 10 includes an applicator body 13, a sliding body 14 slidably held inside the applicator body 13, and a biasing means 15 housed inside the applicator body 13 that biases the sliding body 14 toward the front of the applicator body 13. The applicator 10 also has a pickup tool 17 detachably connected to the front of the sliding body 14. When in use, a microneedle array 12, detachably held at the tip of the pickup tool 17 and protruding from the front of the applicator body 13, moves toward the base of the applicator body 13 against the biasing force of the biasing means 15 while pressed against the surface of the skin 11. In other words, by bringing the applicator body 13 closer to the surface of the skin 11, the biasing means 15 sandwiched between the applicator body 13 and the sliding body 14 is compressed, and the microneedle array 12 held by the pickup tool 17 moves relative to the base side of the applicator body 13 together with the sliding body 14.

[0022] The sliding body 14 has a head portion 18 that detachably holds the pickup tool 17, a shaft portion 19 extending from the base side of the head portion 18, and a base end portion 20 formed at the base end of the shaft portion 19 that is larger in diameter than the shaft portion 19. The applicator body 13 has a cylindrical pressing guide 22 that guides the sliding of the head portion 18 of the sliding body 14 at the front, a guide hole 23 formed in communication with the base side of the pressing guide 22 that guides the sliding of the shaft portion 19 of the sliding body 14, and a guide recess 24 formed in communication with the base side of the guide hole 23 that guides the sliding of the base end portion 20 of the sliding body 14. The biasing means 15 using a coil spring is externally fitted onto the shaft portion 19 of the sliding body 14 and held inside the applicator body 13 (pressing guide 22) so as to be sandwiched between the base side of the head portion 18 and the bottom of the pressing guide 22.

[0023] In the initial state, as shown in Figure 1, the base end 20 of the sliding body 14 is engaged with and held by the front end (in this case, the lower end) of the guide recess 24, thereby maintaining a constant initial protrusion amount of the microneedle array 12. Then, when using the device, moving the applicator body 13 from the state shown in Figure 1 towards the skin 11 (in this case, pushing it downwards) causes the microneedle array 12, which is pressed against the surface of the skin 11, to move toward the base of the applicator body 13, together with the pickup tool 17 and the sliding body 14, against the biasing force of the biasing means 15, resulting in the state shown in Figure 2. In this way, the leading end face 25 of the pressure guide 22 contacts the surface of the skin 11, limiting the movement of the microneedle array 12, so that the microneedle array 12 is pressed against the surface of the skin 11 with a pressure below the set upper limit. Therefore, it is possible to prevent the skin 11 from becoming overloaded and to press the microneedle array 12 against the skin 11 with an appropriate pressure.

[0024] In this embodiment, the pressure guide 22 is integrated with the applicator body 13 (a part of the applicator body 13 (the tip side) is the pressure guide 22), but it may also be detachably (replaceable) attached to the applicator body 13. When the pressure guide is detachably (replaceable) attached to the applicator body, the amount of movement of the microneedle array 12 (= initial protrusion amount of the microneedle array 12) can be adjusted and the pressing force (set upper limit) can be changed by replacing it with a pressure guide of different dimensions (axial length). Alternatively, the amount of movement of the microneedle array 12 can also be adjusted by making the pressure guide itself length-adjustable or by making the attachment position of the pressure guide to the applicator body changeable.

[0025] In this embodiment, the applicator body 13 is formed in a circular shape that is easy to grip, but the shape and dimensions of the applicator body can be selected as appropriate. Furthermore, the sliding body only needs to be slidably held inside the applicator body and movable toward the base side of the applicator body against the biasing force of the biasing means. The shape of the sliding body, the internal structure of the applicator body, and the arrangement of the biasing means are not limited to this embodiment and can be selected as appropriate.

[0026] In this applicator 10, the upper limit of the setting of the pressing force can be changed by adjusting the initial protrusion amount of the microneedle array 12 that protrudes from the front of the applicator body 13 and / or the biasing force of the biasing means 15. As a method of adjusting the initial protrusion amount of the microneedle array 12, in addition to changing the length or mounting position of the pressing guide 22 as described above, there is also a method of changing the axial length of the pickup tool 17. If multiple pickup tools with different axial lengths are prepared in advance, it is possible to easily adjust the initial protrusion amount of the microneedle array 12 and change the pressing force simply by changing the pickup tool. Furthermore, as a method of adjusting the biasing force of the biasing means 15, it is convenient to prepare biasing means with different biasing forces in advance and change the biasing means itself. The biasing force can be easily adjusted (controlled) by the spring constant (length or material of the spring) of the coil spring used as the biasing means 15.

[0027] In this embodiment, a fitting recess 26 is formed on the tip side of the head portion 18 of the sliding body 14, and a fitting projection 27 that can be inserted into and removed from the fitting recess 26 of the sliding body 14 is formed on the base side of the pickup tool 17, with a magnet 28 embedded in the bottom of the fitting recess 26. The fitting projection 27 of the pickup tool 17 is made of a ferromagnetic material such as iron, so that the pickup tool 17 is held to the sliding body 14 by magnetic force. This prevents displacement and tilting of the pickup tool 17, improving its fixing stability and enabling the microneedles to be reliably pressed against the predetermined position on the skin 11, while also facilitating the attachment and detachment of the pickup tool 17, thereby simplifying the replacement work of the microneedle array 12 and the pickup tool 17.

[0028] Here, the fitting recess and fitting projection only need to be formed to be able to insert and remove from each other, and their shape and size can be selected as appropriate. Furthermore, if the pickup tool can be held (fixed) to the sliding body simply by fitting the fitting projection of the pickup tool into the fitting recess of the sliding body, magnetic retention may be omitted. When the pickup tool is held to the sliding body by magnetic force, instead of forming the entire fitting projection out of a ferromagnetic material, a ferromagnetic material may be attached to the leading end of the fitting projection, or the entire pickup tool may be formed out of a magnetic material. Alternatively, a magnet may be attached to the leading end of the fitting projection of the pickup tool, and a ferromagnetic material such as iron may be embedded in the bottom of the fitting recess of the sliding body. Furthermore, the fitting recess of the head and the fitting projection of the pickup tool may be omitted, and the pickup tool may be directly attracted to the tip surface of the head by magnetic force, or a fitting projection may be formed on the head and a fitting recess may be formed on the pickup tool.

[0029] Although embodiments of the present invention have been described above, the present invention is not limited in any way to the configurations described in the embodiments described above, and includes other embodiments and modifications that can be considered within the scope of the matters described in the claims. For components of the applicator that do not have a specific material designation, synthetic resins such as polyethylene, polystyrene, and polypropylene are preferably used, but are not limited to these and can be selected as appropriate. [Explanation of symbols]

[0030] 10: Microneedle applicator, 11: Skin, 12: Microneedle array, 13: Applicator body, 14: Sliding body, 15: Biasing means, 17: Pickup tool, 18: Head part, 19: Shaft part, 20: Base end, 22: Pressing guide, 23: Guide hole, 24: Guide recess, 25: End face, 26: Fitting recess, 27: Fitting protrusion, 28: Magnet

Claims

1. A microneedle applicator used when pressing a microneedle array onto the surface of the target skin, A microneedle applicator comprising an applicator body, a sliding body slidably held inside the applicator body, a biasing means housed inside the applicator body and biasing the sliding body toward the front of the applicator body, and a pickup tool detachably connected to the front of the sliding body, wherein, during use, the microneedle array, detachably held at the tip of the pickup tool and protruding from the front of the applicator body, moves toward the base of the applicator body against the biasing force of the biasing means while pressed against the surface of the skin.

2. The microneedle applicator according to claim 1, characterized in that the applicator body has a pressure guide, and when in use, the leading end face of the pressure guide comes into contact with the surface of the skin, thereby limiting the amount of movement of the microneedle array, and so that the microneedle array is pressed against the surface of the skin with a pressure of less than or equal to a set upper limit.

3. The microneedle applicator according to claim 2, characterized in that the set upper limit of the pressing force can be changed by adjusting the initial protrusion amount of the microneedle array protruding from the front of the applicator body and / or the biasing force of the biasing means.

4. The microneedle applicator according to claim 3, characterized in that the initial protrusion amount of the microneedle array can be adjusted by changing the axial length of the pickup tool.

5. The microneedle applicator according to claim 1, characterized in that the pickup tool is held by the sliding body by magnetic force.

6. The microneedle applicator according to claim 1, characterized in that a fitting recess is formed on the tip side of the sliding body, and a fitting projection that can be inserted into and removed from the fitting recess of the sliding body is formed on the base side of the pickup tool.

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