Hollow microneedle and microneedle array chip

Abstract

The application provides a hollow microneedle and a microneedle array chip, and relates to the technical field of medical devices. The hollow microneedle comprises a needle tip, a needle rod and a needle seat, the needle tip, the needle rod and the needle seat are sequentially connected along the axial direction of the hollow microneedle, and a transition chamfer is formed at the connection position of the needle rod and the needle seat. A first liquid flow channel is formed in the needle tip, a second liquid flow channel is formed in the needle rod, and a third liquid flow channel is formed in the needle seat. The first liquid flow channel, the second liquid flow channel and the third liquid flow channel are through. The included angle between the first central axis of the first liquid flow channel and the second central axis of the second liquid flow channel ranges from 0 to 80 degrees. The hollow microneedle provided by the application has good structural strength, can reduce the risk of drug liquid penetration, and improves the drug delivery efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to a hollow microneedle and a microneedle array chip. BACKGROUND

[0002] The human skin includes, from outside to inside, a stratum corneum, a viable epidermis and a dermis. Injection is one of the main administration routes for most drugs at present. Microneedle injection is a new transdermal administration method, which can penetrate the stratum corneum to form an administration channel without stimulating the subcutaneous pain nerves. Compared with traditional subcutaneous injection, microneedle injection can inject drugs directly into the dermis instead of subcutaneous tissue or muscle, reducing patient pain, improving patient compliance, reducing fear of injection, and being relatively safe.

[0003] In the prior art, microneedles used in microneedle injection mainly include solid microneedles, hollow microneedles, dissolvable microneedles, coated microneedles and hydrogel microneedles. Compared with other forms of microneedles, hollow microneedles can provide more drug loading capacity without changing the drug prescription. When the microneedle penetrates the skin, it is subjected to forces from the skin, including axial pressure, lateral pressure, shear force and friction. The thickness of the stratum corneum in the skin is about 10-20 μm, the thickness of the viable epidermis is about 50-100 μm, and the thickness of the dermis is about 1000 μm. Because the dermis contains nerve endings, the length of the microneedle is generally not more than 1000 μm, otherwise the patient will feel pain, and even the needle tip of the microneedle may bleed after penetrating the skin. Multiple microneedles can also be arranged in an array to form a microneedle array chip structure to provide more efficient microneedle injection. The existing microneedles still use the conventional sharp tip bevel opening structure, which is prone to drug liquid leakage from the skin surface, affecting the administration efficiency, and the microneedle is prone to breakage during use, and the structural strength still needs to be improved. SUMMARY

[0004] To solve at least one of the technical problems in the background art, the present application provides a hollow microneedle with good structural strength and reduced risk of drug leakage, improving administration efficiency.

[0005] The present application also provides a microneedle array chip.

[0006] The first aspect of the present application provides a hollow microneedle, comprising:

[0007] a needle tip, a needle shaft and a needle base, which are connected in sequence along the axial direction of the hollow microneedle, and a transition chamfer is formed at the connection between the needle shaft and the needle base;

[0008] The first liquid flow channel is formed in the needle tip, the second liquid flow channel is formed in the needle stem, and the third liquid flow channel is formed in the needle seat;

[0009] The first liquid flow channel, the second liquid flow channel and the third liquid flow channel are through;

[0010] An included angle between a first central axis of the first liquid flow channel and a second central axis of the second liquid flow channel ranges from 0° to 80°.

[0011] According to the hollow microneedle provided by the embodiment of the first aspect of the present application, the overall structural strength of the hollow microneedle is improved by optimizing the connection structure between the needle stem and the needle seat, and the risk of drug liquid exosmosis is reduced by optimizing the liquid outlet angle of the first liquid flow channel in the needle tip. Specifically, the hollow microneedle comprises a needle tip, a needle stem and a needle seat, which are connected in sequence along the axial direction of the hollow microneedle. A transition chamfer is formed at the connection between the needle stem and the needle seat, so that the connection between the needle stem and the needle seat is smoothly transitioned, the stress concentration at the connection between the needle stem and the needle seat is reduced, and the fracture phenomenon of the connection between the needle stem and the needle seat during the process of the hollow microneedle penetrating into the skin is avoided, the risk of needle breakage is reduced, and the structural strength of the hollow microneedle is enhanced. The first liquid flow channel is formed in the needle tip, the second liquid flow channel is formed in the needle stem, and the third liquid flow channel is formed in the needle seat, and the first liquid flow channel, the second liquid flow channel and the third liquid flow channel are through, so as to facilitate the circulation of the drug liquid. The drug liquid passes through the third liquid flow channel, the second liquid flow channel and the first liquid flow channel in sequence and flows out from the first liquid flow channel. An included angle between a first central axis of the first liquid flow channel and a second central axis of the second liquid flow channel ranges from 0° to 80°. The emission angle of the drug liquid flowing through the first liquid flow channel is diversified designed, the liquid flow direction is changed, the flow speed is reduced, the pressure is reduced, and the risk of exosmosis is reduced, so that the drug liquid can be better released into the skin tissue. In summary, the hollow microneedle provided by the embodiment of the present application has good structural strength, can reduce the risk of drug exosmosis, and can improve the drug efficiency.

[0012] According to one embodiment of the present application, the tip of the needle tip is formed as a pointed top, the tip of the needle tip is formed as a pointed bottom, and the radial cross-sectional area of the needle tip decreases from the pointed bottom to the pointed top;

[0013] A connecting surface is formed between the pointed top and the pointed bottom, and the liquid outlet of the first liquid flow channel is formed on the connecting surface.

[0014] According to one embodiment of the present application, the connecting surface comprises a bevel, a first annular side surface, a first side plane and a second side plane, the first side plane and the second side plane intersect at a first intersection line, the liquid outlet is formed on the bevel, the angle between the bevel and the first intersection line ranges from 20° to 80°, and the angle between the bevel and the axis of the hollow microneedle ranges from 20° to 80°.

[0015] Alternatively, the connecting surface comprises a bevel, a first annular side surface, a first side plane and a second side plane, a first transition connecting surface is formed at the intersection of the first side plane and the second side plane, the angle between the bevel and the first transition connecting surface ranges from 20° to 80°, and the angle between the bevel and the axis of the hollow microneedle ranges from 20° to 80°.

[0016] Alternatively, the connecting surface is a tapered surface, and the liquid outlet is formed on the tapered surface.

[0017] According to one embodiment of the present application, the length of the second liquid flow channel is greater than or equal to 100 μm.

[0018] The total volume of the first liquid flow channel and the second liquid flow channel accounts for 30%-80% of the total volume of the needle tip and the needle shaft.

[0019] According to one embodiment of the present application, the first end of the needle shaft is directed towards the needle holder, the second end of the needle shaft is directed towards the needle tip, and the radial cross-sectional area of the needle shaft decreases from the first end of the needle shaft to the second end of the needle shaft.

[0020] According to one embodiment of the present application, the needle shaft is a cone structure, and the cone comprises a second annular side surface, a third side plane and a fourth side plane connected in a surrounding manner.

[0021] The third side plane and the fourth side plane intersect at a second intersection line, the second intersection line is parallel to the axis of the hollow microneedle, and the second annular side surface is inclined towards the second intersection line.

[0022] Alternatively, a second transition connecting surface is formed at the intersection of the third side plane and the fourth side plane, the second transition connecting surface is parallel to the axis of the hollow microneedle, and the second annular side surface is inclined towards the second transition connecting surface.

[0023] According to one embodiment of the present application, the needle shaft comprises at least two body portions.

[0024] The rate of change of the radial cross-sectional area of at least one of the body portions is different from the rate of change of the radial cross-sectional area of the other body portions, or the rate of change of the radial cross-sectional area of all the body portions is the same.

[0025] According to one embodiment of the present application, the first end of the needle holder is away from the needle stem, and the second end of the needle holder is towards the needle stem.

[0026] The radial cross-sectional area of the first end of the needle holder is greater than or equal to the radial cross-sectional area of the second end of the needle holder.

[0027] The radial cross-sectional area of the second end of the needle holder is greater than or equal to the radial cross-sectional area of the first end of the needle stem.

[0028] The diameter of the first end of the needle holder is greater than or equal to 200 μm, and the distance between the first end of the needle holder and the second end of the needle holder is greater than or equal to 100 μm.

[0029] According to one embodiment of the present application, the diameter D of the first end of the needle stem ranges from 10 μm to 200 μm, and the total length L of the needle tip and the needle stem ranges from 200 μm to 1000 μm, with L / D≥2.

[0030] The second aspect of the embodiments of the present application provides a microneedle array chip, comprising:

[0031] a base, wherein a containing cavity adapted to contain a liquid is formed in the base;

[0032] and at least two hollow microneedles according to any one of the embodiments of the first aspect above.

[0033] The hollow microneedles are arranged in the base, and the containing cavity is connected to the third liquid channel. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without any creative effort.

[0035] Figure 1 is a structural schematic diagram of the hollow microneedle provided by the embodiments of the present application Figure One ;

[0036] Figure 2 is a structural cross-sectional view of the hollow microneedle shown in Figure 1 ;

[0037] Figure 3 is a structural schematic diagram of the hollow microneedle provided by the embodiments of the present application Figure Two ;

[0038] Figure 4 is a structural cross-sectional view of the hollow microneedle shown in Figure 3Axonometric diagram of the hollow microneedle shown Figure One ;

[0039] Figure 5 yes Figure 3 Axonometric diagram of the hollow microneedle shown Figure Two ;

[0040] Figure 6 This is a schematic diagram of the structure of the microneedle array chip provided by an embodiment of the present invention. Figure One ;

[0041] Figure 7 This is a schematic diagram of the structure of the microneedle array chip provided by an embodiment of the present invention. Figure Two ;

[0042] Figure 8 This is a schematic diagram of the structure of the microneedle array chip provided by an embodiment of the present invention. Figure Three .

[0043] Reference numerals:

[0044] 1. Hollow microneedles; 2. Microneedle array chip;

[0045] 10. Needle tip; 101. First liquid flow channel; 1011. Liquid outlet; 102. Connecting surface; 1021. Beveled surface; 1022. First annular side surface; 1023. First side plane; 1024. Second side plane; 1025. First intersection line; 1026. First transition connecting surface; 11. Needle shaft; 111. Second liquid flow channel; 113. Transition chamfer; 114. Second annular side surface; 115. Third side plane; 116. Fourth side plane; 117. Second intersection line; 118. Second transition connecting surface; 12. Needle seat; 121. Third liquid flow channel;

[0046] 20. Base. DETAILED DESCRIPTION

[0047] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0048] In the description of the embodiments of the present application, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the present application. In addition, the terms "first", "second", "third" are only for the purpose of description and cannot be understood as indicating or implying relative importance.

[0049] In the description of the embodiments of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "connected", "connected" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0050] In the embodiments of the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0051] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in the present application and the features of different embodiments or examples without contradiction.

[0052] As Figures 1 to 5As shown, the first aspect embodiment of the present application provides a hollow microneedle 1, which comprises a needle tip 10, a needle shaft 11 and a needle base 12. The needle tip 10, the needle shaft 11 and the needle base 12 are sequentially connected along the axial direction of the hollow microneedle 1. The connection between the needle shaft 11 and the needle base 12 forms a transition chamfer 113. The needle tip 10 forms a first liquid channel 101, the needle shaft 11 forms a second liquid channel 111, and the needle base 12 forms a third liquid channel 121. The first liquid channel 101, the second liquid channel 111 and the third liquid channel 121 are through. The included angle between the first central axis of the first liquid channel 101 and the second central axis of the second liquid channel 111 ranges from 0° to 80°.

[0053] The needle tip 10 is the part of the hollow microneedle 1 used to pierce the skin, and the drug solution also flows out from the needle tip 10. The needle base 12 can also be called a cutoff part. When the hollow microneedle 1 pierces the skin, the needle base 12 contacts the skin and prevents the hollow microneedle 1 from continuing to pierce the deep skin, especially the subcutaneous tissue, thereby avoiding bleeding and pain. The first liquid channel 101, the second liquid channel 111 and the third liquid channel 121 are integrally connected to form a channel. The drug solution flows through the third liquid channel 121, the second liquid channel 111 and the first liquid channel 101 in sequence. The second liquid channel 111 can have a variable diameter feature, and the diameter of the second liquid channel 111 gradually decreases towards the needle tip 10. The first liquid channel 101 can also have a variable diameter feature, and the diameter change rate of the first liquid channel 101 is consistent with that of the second liquid channel 111. The included angle between the first central axis of the first liquid channel 101 and the second central axis of the second liquid channel 111 ranges from 0° to 80°. Within this range, the specific included angle value can be determined according to the actual situation, so that the structure design of the hollow microneedle 1 is more diversified, and the application scenarios are more extensive. Based on the above-mentioned included angle value range, in the embodiment of the present application, the included angle between the first central axis of the first liquid channel 101 and the second central axis of the second liquid channel 111 can be determined to range from 0° to 50°.

[0054] According to the hollow microneedle 1 provided by the embodiment of the first aspect of the present application, the overall structural strength of the hollow microneedle 1 is improved by optimizing the connection structure between the needle shaft 11 and the needle base 12, and the risk of drug liquid exosmosis is reduced by optimizing the liquid outlet angle of the first liquid flow channel 101 in the needle tip 10. Specifically, the hollow microneedle 1 comprises a needle tip 10, a needle shaft 11 and a needle base 12, which are connected in sequence along the axial direction of the hollow microneedle 1. The transition chamfer 113 is formed at the connection between the needle shaft 11 and the needle base 12, so that the smooth transition between the needle shaft 11 and the needle base 12 is realized, the stress concentration at the connection between the needle shaft 11 and the needle base 12 is reduced, and the fracture phenomenon of the connection between the needle shaft 11 and the needle base 12 during the process of the hollow microneedle 1 penetrating into the skin is avoided, thereby reducing the risk of needle breakage and enhancing the structural strength of the hollow microneedle 1. The first liquid flow channel 101 is formed in the needle tip 10, the second liquid flow channel 111 is formed in the needle shaft 11, and the third liquid flow channel 121 is formed in the needle base 12. The first liquid flow channel 101, the second liquid flow channel 111 and the third liquid flow channel 121 are through, so as to facilitate the flow of drug liquid. The drug liquid sequentially passes through the third liquid flow channel 121, the second liquid flow channel 111 and the first liquid flow channel 101, and flows out from the first liquid flow channel 101. The included angle between the first central axis of the first liquid flow channel 101 and the second central axis of the second liquid flow channel 111 ranges from 0° to 80°. The ejection angle of the drug liquid flowing through the first liquid flow channel 101 is diversifiedly designed, the liquid flow direction is changed, the flow speed is reduced, the pressure is reduced, and the risk of exosmosis is reduced, so that the drug liquid can be better released into the skin tissue. In summary, the hollow microneedle 1 provided by the embodiment of the present application has good structural strength, can reduce the risk of drug exosmosis, and can improve the drug efficiency.

[0055] As shown in the drawings, Figure 1 In the embodiment of the present application, the end of the needle tip 10 away from the needle shaft 11 forms a pointed top, and the end of the needle tip 10 towards the needle shaft 11 forms a pointed bottom. The radial cross-sectional area of the needle tip 10 decreases from the pointed bottom to the pointed top. The connecting surface 102 is formed between the pointed top and the pointed bottom, and the liquid outlet 1011 of the first liquid flow channel 101 is formed on the connecting surface 102. The radial cross-sectional area of the needle tip 10 decreases, which means that the needle tip 10 is in a contraction state when it extends from the pointed bottom to the pointed top. Further, the needle tip 10 can be sharply contracted or gently contracted. The connecting surface 102 is the side surface of the needle tip 10, connecting the pointed top and the pointed bottom, and the liquid outlet 1011 of the first liquid flow channel 101 is formed on the connecting surface 102.

[0056] As shown in the drawings, Figures 3 to 5As shown, in the embodiment of the present application, the connecting surface 102 comprises an oblique surface 1021, a first annular side surface 1022, a first side plane 1023 and a second side plane 1024 which are connected in intersection, the first side plane 1023 and the second side plane 1024 intersect at a first intersection line 1025, the liquid outlet 1011 is formed on the oblique surface 1021, the included angle between the oblique surface 1021 and the first intersection line 1025 ranges from 20° to 80°, and the included angle between the oblique surface 1021 and the axis of the hollow microneedle 1 ranges from 20° to 80°; or, the connecting surface 102 comprises an oblique surface 1021, a first annular side surface 1022, a first side plane 1023 and a second side plane 1024 which are connected in intersection, a first transition connecting surface 1026 is formed at the intersection of the first side plane 1023 and the second side plane 1024, the included angle between the oblique surface 1021 and the first transition connecting surface 1026 ranges from 20° to 80°, and the included angle between the oblique surface 1021 and the axis of the hollow microneedle 1 ranges from 20° to 80°; or, the connecting surface 102 is a tapered surface, and the liquid outlet 1011 is formed on the tapered surface. The connecting surface 102 can have various shapes, and correspondingly, the shape of the needle tip 10 can also have various shapes.

[0057] Specifically, the two sides of the first annular side surface 1022 are connected with the first side plane 1023 and the second side plane 1024 respectively, the first side plane 1023 and the second side plane 1024 intersect at the first intersection line 1025, and the oblique surface 1021 intersects with the first annular side surface 1022, the first side plane 1023 and the second side plane 1024, at this time, the projection shape of the needle tip 10 on the horizontal plane is in the shape of a water drop; the first transition connecting surface 1026 can also be formed at the intersection of the first side plane 1023 and the second side plane 1024, which can reduce the difficulty of processing technology; the connecting surface 102 can also be a tapered surface, which can include a triangular pyramid surface, a quadrangular pyramid surface, a pentagonal pyramid surface, a circular cone surface, etc., at this time, the needle tip 10 correspondingly forms the structure of a triangular pyramid, a quadrangular pyramid, a pentagonal pyramid or a circular cone, and the projection shape of the needle tip 10 on the horizontal plane is a triangle or a polygon. By limiting the included angle between the oblique surface 1021 and the first intersection line 1025 or the first transition connecting surface 1026 to range from 20° to 80°, and limiting the included angle between the oblique surface 1021 and the axis of the hollow microneedle 1 to range from 20° to 80°, the angle of the liquid ejected from the liquid outlet 1011 can be ensured to be within a reasonable range, and the risk of liquid penetration can be reduced.

[0058] In the embodiment of the present application, the length of the second liquid flow channel 111 is greater than or equal to 100 μm; the total volume of the first liquid flow channel 101 and the second liquid flow channel 111 accounts for 30%-80% of the total volume of the needle tip 10 and the needle shaft 11. Through the above-mentioned limitation of the flow channel structure, the delivery amount of the drug solution is effectively ensured to be within a reasonable range, avoiding the phenomenon of liquid leakage caused by excessive delivery amount of the drug solution due to the excessively large volume of the flow channel, and also avoiding the phenomenon of insufficient delivery amount of the drug solution due to the excessively small volume of the flow channel.

[0059] As shown in Figures 1 to 3 , in the embodiment of the present application, the first end of the needle shaft 11 faces the needle holder 12, the second end of the needle shaft 11 faces the needle tip 10, and the radial cross-sectional area of the needle shaft 11 decreases from the first end to the second end. This structure can reduce the initial contact area of the needle shaft 11 with the skin, increase the pressure, and be more beneficial to piercing the skin. The needle shaft 11 can be a one-piece structure or a combined structure composed of multiple parts.

[0060] As shown in Figures 3 to 5 , in the embodiment of the present application, the needle shaft 11 is a conical structure, the cone includes a second annular side surface 114, a third side surface 115 and a fourth side surface 116 connected around, the third side surface 115 and the fourth side surface 116 intersect at a second intersection line 117, the second intersection line 117 is parallel to the axis of the hollow microneedle 1, and the second annular side surface 114 is inclined toward the second intersection line 117; or, the third side surface 115 and the fourth side surface 116 intersect to form a second transition connecting surface 118, the second transition connecting surface 118 is parallel to the axis of the hollow microneedle 1, and the second annular side surface 114 is inclined toward the second transition connecting surface 118. The frustum structure of the needle shaft 11 is a one-piece structure, and the trend of the decreasing radial cross-sectional area is relatively gentle. The two sides of the second annular side surface 114 are connected with the third side surface 115 and the fourth side surface 116 respectively, the third side surface 115 and the fourth side surface 116 intersect at the second intersection line 117, in this way, the second annular side surface 114, the third side surface 115 and the fourth side surface 116 form a conical surface, and the third side surface 115 and the fourth side surface 116 can also form the second transition connecting surface 118, which can reduce the difficulty of processing technology. The second intersection line 117 or the second transition connecting surface 118 is parallel to the axis of the hollow microneedle 1, and the second annular side surface 114 is inclined toward the second intersection line 117 or the second transition connecting surface 118, the whole needle shaft 11 has a structure feature of being thick at the bottom and thin at the top. Further, the included angle between the second annular side surface 114 and the axis of the hollow microneedle 1 is not more than 80°.

[0061] As shown in Figure 3 and Figure 4 , in the embodiment of the present application, the first intersection line 1025 is collinear with the second intersection line 117.

[0062] AsFigure 5 As shown, in an embodiment of the present invention, the first transition connection surface 1026 and the second transition connection surface 118 can be connected to form a whole surface.

[0063] like Figure 1 As shown, in an embodiment of the present invention, the needle bar 11 includes at least two main bodies; at least one main body has a different rate of change in radial cross-sectional area than the other main bodies, or all main bodies have the same rate of change in radial cross-sectional area. The needle bar 11 can be composed of a plurality of main bodies, each of which has a varying radial cross-sectional area, and the rates of change in radial cross-sectional area between the main bodies can be the same or different.

[0064] In an embodiment of the present invention, the radial cross-sectional area of ​​the main body portion may also remain unchanged. The main body portion may be a truncated cone, a cylinder, a polygonal pyramid, or a combination of the above shapes. Figure 1 The structure of the needle rod 11 shown in FIG. 1 includes a truncated cone with a varying radial cross-sectional area and a prism with a constant radial cross-sectional area.

[0065] like Figures 1 to 3 As shown, in an embodiment of the present invention, the first end of the needle hub 12 faces away from the needle rod 11, and the second end of the needle hub 12 faces the needle rod 11; the radial cross-sectional area of ​​the first end of the needle hub 12 is greater than or equal to the radial cross-sectional area of ​​the second end of the needle hub 12; the radial cross-sectional area of ​​the second end of the needle hub 12 is greater than or equal to the radial cross-sectional area of ​​the first end of the needle rod 11; the diameter of the first end of the needle hub 12 is greater than or equal to 200 μm, and the distance between the first end of the needle hub 12 and the second end of the needle hub 12 is greater than or equal to 100 μm. The overall shape of the needle hub 12 is a boss shape, which may include structures such as a cylinder, a truncated cone, a prism, and a truncated pyramid, which is not specifically limited in the embodiment of the present invention. The distance between the first end of the needle hub 12 and the second end of the needle hub 12 is the height of the needle hub 12, and the height is greater than or equal to 100 μm to ensure the structural strength of the needle hub 12.

[0066] Furthermore, a transition portion may be provided between the needle hub 12 and the needle shaft 11, wherein the radial cross-sectional area of ​​the transition portion decreases smoothly in a curved manner toward the needle shaft 11. The maximum diameter of the transition portion is less than or equal to the radial cross-sectional area of ​​the second end of the needle hub 12, and the minimum diameter of the transition portion is greater than or equal to the radial cross-sectional area of ​​the first end of the needle shaft 11. The needle shaft 11, transition portion, and needle hub 12 may be directly integrally formed.

[0067] When hollow microneedle 1 penetrates the skin, the contact between needle hub 12 and the skin prevents it from penetrating deeper into the skin, particularly the subcutaneous layer, after reaching a certain depth. This prevents bleeding and pain. Furthermore, when hollow microneedle 1 penetrates the skin, the skin's force on hollow microneedle 1 is transmitted sequentially from needle tip 10 and needle shaft 11 to needle hub 12. Furthermore, the presence of the transition connection also forms a transition chamfer 113, creating a smooth transition. This reduces stress concentration and the risk of needle breakage, increases the structural strength of hollow microneedle 1, and protects the skin.

[0068] In an embodiment of the present invention, the diameter D of the first end of the needle rod 11 is in the range of 10-200 μm, the total length L of the needle tip 10 and the needle rod 11 is in the range of 200-1000 μm, and L / D≥2.

[0069] Furthermore, in one embodiment of the present invention, the total length L of the needle tip 10 and the needle shaft 11 is in the range of 300-800 μm, and the diameter D of the first end of the needle shaft 11 is in the range of 50-150 μm.

[0070] like Figures 6 to 8 As shown, a second embodiment of the present invention provides a microneedle array chip 2, comprising a base 20 and at least two hollow microneedles 1 according to any of the first embodiments. A cavity suitable for containing a liquid medicine is formed within the base 20, and the hollow microneedles 1 are disposed on the base 20, with the cavity communicating with a third liquid flow channel 121.

[0071] The base 20 can be any carrier capable of supporting the hollow microneedles 1, or a container for storing drugs, with its cavity containing the drug solution. The base 20 can be integrally formed with the hollow microneedles 1, which are fixed to the base 20 via the needle holder 12. Multiple hollow microneedles 1 are arranged in an array on the base 20. When piercing the skin, the skin will sag due to surface tension. Therefore, the center-to-center spacing between adjacent hollow microneedles 1 should be greater than the size of the skin sag; otherwise, the hollow microneedles 1 will have difficulty piercing the skin. Accordingly, in the embodiment of the present invention, the center-to-center spacing between adjacent hollow microneedles 1 is greater than 1.5 mm. When the hollow microneedle 1 penetrates the skin, the force exerted by the skin on the hollow microneedle 1 is transmitted from the needle tip 10, the needle rod 11, the needle seat 12 to the base 20 in sequence. The size from the needle rod 11 to the needle seat 12 and then to the base 20 will not increase suddenly, and the existence of the transition connection part can also form a transition chamfer structure, which provides a smooth transition, reduces hazards such as stress concentration, reduces the risk of needle breakage, increases the structural strength of the hollow microneedle 1 on the base 20, and also protects the skin.

[0072] According to the micro-needle array chip 2 provided by the embodiment of the second aspect of the present application, the hollow micro-needle 1 on the base 20 comprises a needle tip 10, a needle rod 11 and a needle seat 12, the needle tip 10, the needle rod 11 and the needle seat 12 are sequentially connected along the axial direction of the hollow micro-needle 1, a transition chamfer 113 is formed at the connection between the needle rod 11 and the needle seat 12, so that the transition between the needle rod 11 and the needle seat 12 is smooth, the stress concentration at the connection between the needle rod 11 and the needle seat 12 is reduced, so that the fracture phenomenon at the connection between the needle rod 11 and the needle seat 12 during the process of penetrating the skin can be avoided, the risk of needle breakage is reduced, and the structural strength of the hollow micro-needle 1 is enhanced; the first liquid flow channel 101 is formed in the needle tip 10, the second liquid flow channel 111 is formed in the needle rod 11, and the third liquid flow channel 121 is formed in the needle seat 12, and the first liquid flow channel 101, the second liquid flow channel 111 and the third liquid flow channel 121 are through, so as to facilitate the flow of the drug liquid, the drug liquid sequentially passes through the third liquid flow channel 121, the second liquid flow channel 111 and the first liquid flow channel 101, and flows out from the first liquid flow channel 101, wherein the included angle between the first central axis of the first liquid flow channel 101 and the second central axis of the second liquid flow channel 111 ranges from 0° to 80°, the exit angle of the drug liquid flowing through the first liquid flow channel 101 is diversified, the liquid flow direction changes, the flow speed is reduced, the pressure is reduced, and the risk of liquid penetration is reduced, so that the drug liquid can be better released into the skin tissue. In summary, the micro-needle array chip 2 provided by the embodiment of the present application has good overall structural strength of the hollow micro-needle 1, and can reduce the risk of drug liquid penetration and improve the drug delivery efficiency.

[0073] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A hollow microneedle (1) characterized in that, The hollow microneedle (1) comprises: a needle tip (10), a needle shaft (11) and a needle base (12), which are sequentially connected along the axial direction of the hollow microneedle (1), and a transition chamfer (113) is formed at the connection between the needle shaft (11) and the needle base (12); a first liquid flow channel (101) is formed in the needle tip (10), a second liquid flow channel (111) is formed in the needle shaft (11), and a third liquid flow channel (121) is formed in the needle base (12); the first liquid flow channel (101), the second liquid flow channel (111) and the third liquid flow channel (121) are through; the included angle between the first central axis of the first liquid flow channel (101) and the second central axis of the second liquid flow channel (111) ranges from 0° to 80°; a pointed top is formed at the end of the needle tip (10) away from the needle shaft (11), a pointed bottom is formed at the end of the needle tip (10) toward the needle shaft (11), and the radial cross-sectional area of the needle tip (10) decreases from the pointed bottom to the pointed top; a connecting surface (102) is formed between the pointed top and the pointed bottom, and a liquid outlet (1011) of the first liquid flow channel (101) is formed on the connecting surface (102); the connecting surface (102) comprises an oblique cutting surface (1021), a first annular side surface (1022), a first side plane (1023) and a second side plane (1024) which are connected in intersection, the first side plane (1023) and the second side plane (1024) intersect at a first intersection line (1025), the liquid outlet (1011) is formed on the oblique cutting surface (1021), the included angle between the oblique cutting surface (1021) and the first intersection line (1025) ranges from 20° to 80°, and the included angle between the oblique cutting surface (1021) and the axis of the hollow microneedle (1) ranges from 20° to 80°; alternatively, the connecting surface (102) comprises an oblique cutting surface (1021), a first annular side surface (1022), a first side plane (1023) and a second side plane (1024) which are connected in intersection, a first transition connecting surface (1026) is formed at the intersection of the first side plane (1023) and the second side plane (1024), the included angle between the oblique cutting surface (1021) and the first transition connecting surface (1026) ranges from 20° to 80°, and the included angle between the oblique cutting surface (1021) and the axis of the hollow microneedle (1) ranges from 20° to 80°; the length of the second liquid flow channel (111) is greater than or equal to 100 μm.

2. The hollow microneedle (1) according to claim 1, characterized in that the total volume of the first liquid flow channel (101) and the second liquid flow channel (111) accounts for 30%-80% of the total volume of the needle tip (10) and the needle shaft (11).

3. Hollow microneedle (1) according to any one of claims 1 to 2, characterized in that The first end of the needle stem (11) faces the needle base (12), the second end of the needle stem (11) faces the needle tip (10), and the radial cross-sectional area of the needle stem (11) decreases from the first end to the second end of the needle stem (11).

4. The hollow microneedle (1) according to claim 3, characterized in that The needle stem (11) is a conical structure, and the conical structure comprises a second annular side surface (114), a third side surface (115) and a fourth side surface (116) connected in sequence; The third side surface (115) and the fourth side surface (116) intersect at a second intersection line (117), the second intersection line (117) is parallel to the axis of the hollow microneedle (1), and the second annular side surface (114) is inclined towards the second intersection line (117); Or, the third side surface (115) and the fourth side surface (116) form a second transition connecting surface (118) at the intersection, the second transition connecting surface (118) is parallel to the axis of the hollow microneedle (1), and the second annular side surface (114) is inclined towards the second transition connecting surface (118).

5. The hollow microneedle (1) according to claim 3, characterized in that The needle stem (11) comprises at least two body portions; The rate of change of the radial cross-sectional area of at least one of the body portions is different from the rate of change of the radial cross-sectional area of another body portion, or the rates of change of the radial cross-sectional areas of all the body portions are the same.

6. The hollow microneedle (1) according to claim 3, characterized in that The first end of the needle base (12) faces away from the needle stem (11), and the second end of the needle base (12) faces the needle stem (11); The radial cross-sectional area of the first end of the needle base (12) is greater than or equal to the radial cross-sectional area of the second end of the needle base (12); The radial cross-sectional area of the second end of the needle base (12) is greater than or equal to the radial cross-sectional area of the first end of the needle stem (11); The diameter of the first end of the needle base (12) is greater than or equal to 200 μm, and the distance between the first end of the needle base (12) and the second end of the needle base (12) is greater than or equal to 100 μm.

7. The hollow microneedle (1) according to claim 3, characterized in that The diameter D of the first end of the needle stem (11) ranges from 10 μm to 200 μm, the total length L of the needle tip (10) and the needle stem (11) ranges from 200 μm to 1000 μm, and L / D≥2.

8. A microneedle array chip (2) characterized by, It comprises: a base (20) in which a containing cavity adapted to contain a liquid medicine is formed; and at least two hollow microneedles (1) according to any one of claims 1 to 7; The hollow microneedle (1) is arranged in the base (20), and the containing cavity is in communication with the third liquid flow channel (121).

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