Capillary hollow metal microneedle, array chip and application thereof

Abstract

The present invention discloses a capillary hollow metal microneedle, characterized in that it is an eccentric capillary hollow metal microneedle, comprising a needle rod and a needle tip, the upper surface of the needle tip is an elliptical plane section inclined at an acute angle to the axis of the needle rod, the top of the upper surface is a pointed top, and the bottom is a pointed bottom; the inside of the needle rod is provided with a cylindrical through hole that penetrates up and down along the length direction to form a hollow structure, the needle rod and the axial center of the through hole are eccentric, and the axis of the through hole is translated to the side of the pointed bottom to a set distance, so that the wall thickness of the needle rod near the pointed top is not less than 1.2 times the wall thickness of the needle rod near the pointed bottom, so as to significantly improve the axial strength and electrical and thermal conductivity of the wall of the needle rod near the pointed top. The present invention also discloses an array chip using the capillary hollow metal microneedle and its application. The present invention improves the mechanical strength, liquid conduction ability, electrical and thermal conductivity of the microneedle through the eccentric structural design of the needle rod and the center of the through hole, and expands the scope of application.

Description

Technical Field

[0001] The present invention relates to the technical field of medical and cosmetic injection equipment, and in particular to a capillary hollow metal microneedle, an array chip and applications thereof. Background Art

[0002] Human skin consists of three layers of tissue from the outside to the inside: the stratum corneum, the active epidermis and the dermis. The thickness of the stratum corneum is about 30-50 microns, the thickness of the epidermis is about 50-100 microns, and the dermis is the main component of the skin, containing a large number of living cells, nerve tissue and vascular tissue. The outer diameter of the needle used in the traditional subcutaneous injection method is generally 0.4-3.4 mm. When injecting, the needle must penetrate the skin and deep into the muscle, which will undoubtedly touch the blood vessels and damage a large amount of nerve tissue. Therefore, in addition to bleeding, patients often feel more severe pain.

[0003] In order to solve this problem, microneedles and their arrays have emerged. By pressing the needles, a large number of micron-sized channels can be instantly generated in the stratum corneum and epidermis of the skin to significantly improve the permeability of drugs. Since the microneedles of the microneedle device are sharp and short, and there are no nerve tissues and blood vessels in the stratum corneum of the skin, there will be no pain or bleeding when using it, and the minimally invasive holes can heal in a relatively short time. Therefore, microneedle devices are not only widely used in medical drug delivery, but also widely used to promote the absorption and penetration of beauty products. Microneedle drug delivery does not require professional personnel to operate, is flexible and convenient to use, and drug delivery can be interrupted at any time, so it is more easily accepted by patients.

[0004] When users administer drugs through a microneedle device, they generally press the microneedle array, causing the microneedle array to instantly generate a large number of micrometer-sized channels in the stratum corneum and epidermis of the skin. The drug is then administered through the built-in through-holes in the microneedle device, allowing the drug to quickly penetrate and diffuse through the channels in the skin.

[0005] However, in order to ensure drug delivery efficiency and avoid bending or breaking of microneedles, the diameter of the hollow microneedles in the prior art is still relatively large. The diameter of the microneedle tip is generally 5 to 10 μm, and the diameter of the needle base is generally 20 to 300 μm. Due to individual differences in the thickness of human skin, it is impossible to completely avoid contact with the dermis during drug delivery to avoid pain (if it contacts the dermis, it will cause slight pain). The minimally invasive holes formed after piercing the skin also need a certain amount of time to heal. Since the microneedle drug delivery site does not touch the nerve tissue and blood vessels on the body surface, it will not cause pain or bleeding;

[0006] Generally speaking, the smaller the diameter and the sharper the microneedles of a microneedle device are, even if they come into contact with the dermis, the less pain they cause, and the shorter the healing time of the micro-invasive holes formed by the drug administration, and the less bleeding they will cause. However, when the diameter of a microneedle, especially a hollow microneedle, is smaller, its mechanical strength is lower, and it is easy to cause the needle to break and bend; at the same time, the smaller its diameter is, the smaller its conduction capacity for injection drug administration, and the drug administration efficiency is also reduced; because the cross-section of the infusion hole of the needle is too small, it is easy to cause the infusion hole to be blocked at the needle head, affecting the diffusion of the drug and making the efficacy of various places unstable; and if the pressure of drug injection is simply increased, it is easy for the drug to overflow along the needle rod to the outside of the skin, resulting in a waste of liquid medicine. At the same time, the existing microneedles and microneedle devices have poor electrical and thermal conductivity and are not suitable for electric pulse therapy or thermal moxibustion therapy. Summary of the invention

[0007] In view of the above shortcomings, the purpose of the present invention is to provide a capillary hollow metal microneedle, which mainly solves the problems of reduced mechanical strength, easy needle breakage, low conduction capacity, and inapplicability to electric pulse therapy or thermal moxibustion therapy when the diameter of the microneedle is reduced through the eccentric structural design of the needle rod and the center of the through hole;

[0008] The present invention also aims to provide an array chip using oriented capillary hollow metal microneedles to solve the problem of reduced drug delivery efficiency when the diameter of the microneedles is reduced;

[0009] The present invention also aims to use the array chip to prepare a treatment unit, and further make it into an application of a directional subcutaneous drug delivery treatment device or a beauty device to solve the pain caused by the operation process and further shorten the time required for minimally invasive small holes to heal and improve safety.

[0010] In order to achieve the above object, the technical solution adopted by the present invention is:

[0011] A capillary hollow metal microneedle, characterized in that it is an eccentric capillary hollow metal microneedle, comprising a cylindrical metal needle rod and a needle tip arranged at the front section of the needle rod, the upper surface of the needle tip is an elliptical plane section inclined at an acute angle to the axis of the needle rod, the top of the upper surface is a pointed top, and the bottom end is a pointed bottom; the interior of the needle rod is provided with a cylindrical through hole that passes through from top to bottom along the length direction to form a hollow structure, the needle rod and the axial center of the through hole are eccentric, the axis of the through hole is translated to the side of the pointed bottom to a set distance, so that the wall thickness of the needle rod near the pointed top is not less than 1.2 times the wall thickness of the needle rod near the pointed bottom, so as to significantly improve the axial strength and electrical and thermal conductivity of the wall of the needle rod near the pointed top.

[0012] The upper surface of the needle tip is set to have an acute angle of 15 to 45 degrees with respect to the axis of the needle bar.

[0013] Assuming that the diameter of the needle rod is D1, the diameter of the through hole is D2, the wall thickness of the needle rod near the tip is T1, and the wall thickness of the needle rod near the tip is T2, then:

[0014] T1≥(D1-D2)*6 / 11 (Formula 1),

[0015] T2≤(D1-D2)*5 / 11 (Formula 2),

[0016] Assuming that the distance between the needle bar and the axis of the through hole, that is, the distance between the two centers, is L, then:

[0017] L = (D1 - D2) / 2 - T2 (Formula 3).

[0018] The value range of D1 is 0.5 to 150 microns, the diameter D2 of the through hole is 0.2 to 100 microns, and the height is 50 to 1000 microns.

[0019] The cylindrical metal needle rod is a conical column that is wide at the bottom and narrow at the top, with a bottom diameter D3 of 20 to 30 microns, a top diameter D1 of 0.5 to 10 microns, a through hole diameter D2 of 0.2 to 5 microns, and a height of 50 to 500 microns.

[0020] The tip bottom of the needle tip is also provided with a lateral opening which is communicated with the through hole and extends toward the needle rod.

[0021] An array chip using the capillary hollow metal microneedles is characterized in that it includes a plurality of eccentric capillary hollow metal microneedles and an equilateral substrate, wherein the bottoms of the microneedles are arranged on the substrate in a rectangular array, and the upper parts are parallel to each other to form a microneedle array; the inclination direction of the elliptical plane section on the upper surface of each microneedle tip is toward the geometric center of the substrate, so that the through-hole sections on the microneedle tips are centered on the geometric center point of the substrate, are centrally symmetrical, and are distributed at equal distances; the distance between the centers of the microneedles is 100 to 300 microns.

[0022] The outer contours of the substrate and the array are rectangular, circular, triangular or regular hexagonal.

[0023] Each microneedle in the array includes an eccentric capillary hollow metal microneedle, a non-eccentric capillary hollow metal microneedle and a solid capillary metal microneedle, and the inclination direction of the elliptical plane section on the upper surface of the needle tip of each eccentric capillary hollow metal microneedle is toward the geometric center of the substrate, so that the through-hole section on each needle tip is centered on the geometric center point of the carrier, is centrally symmetrical, and is distributed at equal distances; the eccentric capillary hollow metal microneedles, the non-eccentric capillary hollow metal microneedles and the solid capillary metal microneedles are arranged and combined in a set manner to implement local treatment.

[0024] An application of the array chip is characterized in that a plurality of array chips are arranged on a carrier board to form a treatment unit including a plurality of array chips, which is further made into a subcutaneous treatment device; and the subcutaneous treatment device is further made into a subcutaneous drug delivery, electricity delivery or heat delivery treatment or beauty device.

[0025] The material for preparing the capillary hollow metal microneedles of the present invention is medical metal or alloy; the material for preparing the array chip carrier is one of single crystal silicon, medical metal, alloy and polymer resin.

[0026] The beneficial effects of the present invention are:

[0027] 1. The capillary hollow metal microneedle provided by the present invention has an eccentric hollow structure design. While greatly reducing the overall diameter of the microneedle, the mechanical strength is greatly enhanced by increasing the thickness of the needle shaft on the side of the needle tip, thereby solving the problems of reduced mechanical strength of the microneedle when the diameter is reduced, easy needle breakage, and low conduction capacity. Since the wall thickness on the side of the tip is more than 1.2 times the wall thickness on the side of the tip, the axial mechanical strength (especially the axial bending strength) is increased by more than 3 times compared with the conventional thickness, and the thermal and electrical conductivity are increased by more than 2 times compared with the conventional thickness. At the same time, the increase in the side wall thickness also improves the mechanical strength of the tip during puncture. Combined with the set acute angle of the elliptical plane section of the upper surface of the needle tip and the inclination of the needle shaft axis, the sharpness of the tip is greatly improved, the puncture capacity is further improved, and the occurrence of needle breakage or bending is avoided. When the metal microneedle is combined with pulse current therapy or pulse heat moxibustion therapy, due to the larger wall thickness on the side of the tip, it is beneficial to introduce the pulse current or heat into a deeper position in the skin, thereby enhancing the therapeutic effect.

[0028] 2. The eccentric capillary hollow metal microneedle provided by the present invention, based on the inclined opening of the traditional needle, further provides a lateral opening at the tip, thereby improving the ability of the drug to conduct, effectively avoiding the phenomenon of skin blocking the infusion hole, and is more conducive to the rapid diffusion and absorption of the drug, with significant therapeutic effects; at the same time, the direction of drug outlet is accurately determined to be just in front of the side of the needle rod with increased wall thickness, so that the reverse thrust generated when the drug is injected directly acts on the side of the needle rod with increased wall thickness.

[0029] 3. The orientation array chip provided by the present invention makes the cross-section of the through holes on each microneedle tip centered on the geometric center point of the substrate, symmetrically distributed at equal distances, so that during the injection process, when the drug solution enters the skin, it is injected toward the geometric center point of the substrate, and the reaction force generated thereby is directed toward the side of the microneedle shaft with a reinforced wall thickness. On the one hand, the drug solution can penetrate in a specific direction, improve its penetration uniformity, and make the therapeutic effect consistent everywhere. On the other hand, the reaction force generated when the drug solution is injected can act on the side of the eccentric microneedle shaft with a reinforced wall thickness. Since the deformation resistance of this side is enhanced, the deformation and tilt of the microneedle shaft caused by the reverse thrust of the drug solution during injection can be avoided, and the microneedle breakage or bending caused thereby can be avoided;

[0030] 4. The oriented array chip provided by the present invention has an eccentric structural design and reduces the diameter of each microneedle, thereby improving the mechanical strength in specific parts and directions. The substrate area occupied by each microneedle is reduced. Therefore, on an existing substrate of the same area, a larger number of capillary hollow metal microneedles can be arranged to form an array to improve the conduction capacity and conduction efficiency of liquid medicine, electric current or heat, while achieving the effects of preventing needle breakage, safety, and painlessness.

[0031] 5. The subcutaneous injection device provided by the present invention is made of the above-mentioned eccentric capillary hollow metal microneedles and oriented array chips, and the further made subcutaneous drug delivery treatment or beauty device. Due to its microneedle, its diameter is smaller, the needle tip is sharper and more resistant to deformation. Even if it contacts the dermis, it will not cause obvious pain. Moreover, the diameter of the minimally invasive hole formed by its drug delivery is smaller, the healing time is shorter, and it will not cause bleeding, so it is safer and easier to operate.

[0032] 6. The eccentric capillary hollow metal microneedles provided by the present invention form an oriented array chip, an oriented subcutaneous injection device made of the same, and a further oriented subcutaneous drug administration treatment or beauty device, which can accurately guide the outflow direction of the drug solution during injection so that the reaction force of the drug solution received by the microneedles at each location acts vertically on the side of the needle shaft with increased wall thickness, thereby avoiding deformation of the needle shaft and making the drug solution penetrate evenly and having a consistent therapeutic effect at each location; by increasing the number of microneedles on the array chip per unit area, the conduction capacity of the drug solution is improved and the drug administration efficiency is improved, so there is no need to increase the injection pressure during injection, which can avoid the drug from overflowing along the needle shaft to the outside of the skin due to excessive pressure, causing waste of drug solution and pollution of the treatment environment.

[0033] 7. The eccentric capillary hollow metal microneedles provided by the present invention, the oriented array chip composed of them, together with the non-eccentric capillary hollow metal microneedles and solid capillary metal microneedles, form a mixed array, which can be applied to subcutaneous injection, pulse electrotherapy, pulse heat treatment, etc. The oriented subcutaneous composite therapeutic device made of it, and the further oriented subcutaneous drug delivery, electricity supply, heat supply treatment or beauty device, are accurately improved according to the analysis of the injection, electrical conduction and heat conduction processes. The eccentric structure and oriented array are used to form an array of a set shape together with non-eccentric capillary hollow metal microneedles and solid capillary metal microneedles, which can reasonably match the force, stress and mechanical strength of each place, as well as the uniformity of electrical conduction and thermal conduction, so that the array and its chip have good robustness, stable structure, reliable operation, good consistency, flexible and diverse design, can meet different actual needs, and make the therapeutic effect of each place have good consistency.

[0034] The above is an overview of the technical solution of the invention. The present invention will be further described below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of the main structure of the capillary hollow metal microneedle in Example 1 of the present invention;

[0036] Figure 2 Schematic diagram of the top view of the capillary hollow metal microneedle in Example 1 of the present invention;

[0037] Figure 3 This is a schematic diagram of the three-dimensional appearance structure of the capillary hollow metal microneedle in Example 2 of the present invention;

[0038] Figure 4 This is a schematic diagram of the main structure of the capillary hollow metal microneedle according to Example 2 of the present invention;

[0039] Figure 5 This is a schematic diagram of the full cross-sectional structure of the capillary hollow metal microneedle according to Example 2 of the present invention;

[0040] Figure 6 Schematic diagram of the top view of the capillary hollow metal microneedle according to Example 2 of the present invention;

[0041] Figure 7 It is a schematic diagram of the three-dimensional appearance structure of the orientation array chip of the present invention;

[0042] Figure 8 Schematic diagram of the top view of the orientation array chip of the present invention;

[0043] Fig. 9 It is a schematic diagram of the overall cross-sectional structure of the orientation array chip of the present invention along the transverse midline.

[0044] Fig.10This is a schematic diagram of the three-dimensional appearance structure of the mixed array chip of Example 3 of the present invention;

[0045] Fig.11 Schematic diagram of the top view of the mixed array chip according to Embodiment 3 of the present invention;

[0046] Fig.12 It is a schematic diagram of the overall cross-sectional structure of the mixed array chip taken along the horizontal midline of Example 3 of the present invention.

[0047] In the figure, 1, microneedle needle rod; 11, needle tip; 2, flat section; 21, pointed top; 22, pointed bottom; 3, through hole; T1, thickened side wall; T2, reduced thickening side wall; 4, lateral opening; 5, substrate; D1, needle rod top diameter; D2, through hole diameter; D3 needle rod bottom diameter; L, distance between the center of the needle rod top and the center of the through hole; 6, non-eccentric capillary hollow metal microneedle; 7, solid capillary metal microneedle. DETAILED DESCRIPTION

[0048] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined purpose, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0049] Example 1

[0050] See also Figure 1-Figure 9 The capillary hollow metal microneedle provided in this embodiment is an eccentric capillary hollow metal microneedle, which includes a cylindrical metal needle rod 1 and a needle tip 11 arranged at the front section of the needle rod, the upper surface of the needle tip 11 is an elliptical plane section 2 inclined at an acute angle to the axis of the needle rod, the top of the upper surface is a pointed top 21, and the bottom end is a pointed bottom 22; the interior of the needle rod 1 is provided with a cylindrical through hole 3 penetrating up and down along the length direction to form a hollow structure, the needle rod 1 is eccentric to the axial center of the through hole 3, and the axis of the through hole 3 is translated to the side of the pointed bottom 22 to a set distance, so that the wall thickness T1 of the needle rod 1 on the side close to the pointed top 21 is not less than 1.2 times the wall thickness T2 on the side close to the pointed bottom 22 of the needle rod, so as to significantly improve the axial strength of the wall of the needle rod 1 on the side close to the pointed top 21, as well as the electrical and thermal conductivity.

[0051] The upper surface plane section 2 of the needle tip 1 is an ellipse, and the acute angle between the ellipse and the axis of the needle rod 1 is set to be 15 to 45 degrees. In this embodiment, 45 degrees is selected, and in other embodiments, other values ​​can be specifically selected within this range according to actual needs.

[0052] Assuming that the cylindrical diameter of the needle bar 1 is D1, the diameter of the through hole is D2, the wall thickness of the needle bar 1 close to the tip is T1, and the wall thickness of the needle bar close to the tip is T2, then:

[0053] T1≥(D1-D2)*6 / 11; T2≤(D1-D2)*5 / 11.

[0054] The value range of D1 is 0.5 to 150 microns, the diameter D2 of the through hole is 0.2 to 100 microns, and the height is 20 to 1000 microns.

[0055] In this embodiment, D1=75 microns, D2=20 microns, and the height is 200 microns, then: T1≥30 microns; T2≤(D1-D2)*5 / 11, then T2≤25 microns; specifically, in this embodiment, T1=30 microns, T2=25 microns.

[0056] Assuming that the distance between the axis of the needle rod 1 and the through hole 2, that is, the distance between the two centers of the circle is L, then: L = (D1-D2) / 2-T2. In this embodiment, L = (75-20) / 2-25 = 2.5 microns, and the eccentricity between the through hole 2 and the microneedle needle rod is 2.5 microns.

[0057] In other embodiments, T1, T2, D1, D2, and L can select other values ​​within the above range according to actual needs, and the technical effects recorded in the present invention can be achieved.

[0058] Example 2

[0059] See also Figure 3-Figure 9 The capillary hollow metal microneedle provided in this embodiment is basically the same as that in embodiment 1, except that:

[0060] The capillary hollow metal microneedle provided in this embodiment includes a conical cylindrical metal needle rod 1 with a large bottom and a small top, that is, the cylindrical metal needle rod is a conical cylinder with a wide bottom and a narrow top, and its bottom diameter D3 is 20 to 150 microns, the top diameter D1 is 0.5 to 10 microns, the through hole diameter D2 is 0.2 to 5 microns, and the height is 50 to 500 microns.

[0061] In this embodiment, the diameter of D1 is 10 microns, the diameter of the through hole is D2 is 4.5 microns, and D3 is 25 microns.

[0062] The tip of the needle tip is provided with a lateral opening 4 which is connected to the through hole and extends toward the needle rod. In this embodiment, the axial length of the opening 4 is 3 microns and the width is 0.9 microns.

[0063] An array chip using the aforementioned capillary hollow metal microneedles comprises a plurality of eccentric capillary hollow metal microneedles 1 and an equilateral substrate 5, wherein the bottoms of the microneedles 1 are arranged on the substrate 5 in a rectangular array, and the upper parts are mutually parallel to form a microneedle array, and the inclination direction of the elliptical plane section 2 on the upper surface of each microneedle needle tip 11 is all toward the geometric center of the substrate 5, so that the cross-section of the through hole 2 on each microneedle needle tip 11 is centered on the geometric center point of the substrate 5, is centrally symmetrical, and is distributed at equal distances; the distance between the centers of the microneedles is 100 to 300 microns.

[0064] The outer contours of the substrate and the microneedle array may be rectangular, circular, triangular or regular hexagonal, or other suitable shapes.

[0065] In this embodiment, the substrate 5 of the array chip and the microneedle array are both rectangular in shape.

[0066] In the array chip, the distance between the centers of the microneedles 1 in the microneedle array is 100-150 microns, and the microneedles are equidistant and evenly distributed in the length and width directions.

[0067] An application of the aforementioned array chip is to place a plurality of array chips on a carrier board (not shown in the drawings) to form an injection unit including a plurality of array chips, and further to form a subcutaneous injection device.

[0068] The array chip is used to further manufacture the subcutaneous injection device into a therapeutic or cosmetic device for subcutaneous drug administration.

[0069] The material for preparing the capillary hollow metal microneedle 1 of the present invention can be a medical metal or alloy; the material for preparing the array chip substrate or carrier can be one of single crystal silicon, medical metal, alloy, and polymer resin.

[0070] In the application of the array chip, the elliptical plane sections 2 on the upper surfaces of the needle tips of the microneedles 1 on the array chips constituting the injection unit are inclined toward the geometric center of the carrier, so that the through-hole sections 2 on the needle tips of the microneedles are centered on the geometric center point of the carrier, are centrally symmetrical, and are distributed at equal distances, so as to converge the liquid, current or heat introduced by each microneedle in the same direction, thereby enhancing the therapeutic effect.

[0071] In other embodiments, the cross-sectional shape of the microneedle 1 may also be a cone, a polygonal cone or other shapes.

[0072] Example 3

[0073] See also Figure 10-12 The capillary hollow metal microneedles, arrays and applications thereof provided in this embodiment are substantially the same as those in embodiments 1 and 2, except that:

[0074] Each microneedle in the microneedle array includes an eccentric capillary hollow metal microneedle, a non-eccentric capillary hollow metal microneedle and a solid capillary metal microneedle, and the inclination direction of the elliptical plane section on the upper surface of the needle tip of each eccentric capillary hollow metal microneedle is toward the geometric center of the substrate, so that the through-hole section on each needle tip is centered on the geometric center point of the carrier, is centrally symmetrical, and is distributed at equal distances; the eccentric capillary hollow metal microneedles, the non-eccentric capillary hollow metal microneedles and the solid capillary metal microneedles are arranged and combined in a set manner to implement local treatment.

[0075] An application of the array chip is to arrange multiple array chips on a carrier board to form a treatment unit including multiple array chips, which is further made into a subcutaneous treatment device; and the subcutaneous treatment device is further made into a subcutaneous drug, electricity or heat treatment or beauty device.

[0076] Specifically, in the present embodiment, the array chip is a mixed array chip, which is an oriented array chip composed of eccentric capillary hollow metal microneedles 1, and together with non-eccentric capillary hollow metal microneedles 6 and solid capillary metal microneedles 7, it forms a mixed array, which can be applied to subcutaneous injection, pulse electrotherapy, pulse heat treatment, etc.; the oriented subcutaneous composite therapeutic device made thereof, and the further oriented subcutaneous drug delivery, electricity supply, heat supply treatment or beauty device, are precisely improved according to the analysis of the injection, electrical conduction and heat conduction processes, and the eccentric structure and oriented array are used to form an array of a set shape together with non-eccentric capillary hollow metal microneedles and solid capillary metal microneedles, which can reasonably match the force, stress and mechanical strength of each place, as well as the uniformity of electrical conduction and thermal conduction, so that the array and its chip have good firmness, stable structure, reliable operation, good consistency, flexible and diverse design, can meet different practical needs, and make the therapeutic effect of each place have good consistency.

[0077] The shape of the microneedle in this embodiment is a truncated cone, the top of the needle is a platform, and all the microneedles on the array chip (wafer) are of the same height, with the advantages of specific orientation, anti-needle breakage, no scratches, safety and painlessness, etc. The microneedles of each microneedle array unit of the present invention are arranged in an array uniformly and equidistantly, so they can be cut into rectangles (squares or rectangles) of various sizes in units of square millimeters without cutting the needles, which effectively protects the integrity of each microneedle, is conducive to mass production, and can reduce the defective rate of products.

[0078] The invention improves the mechanical strength, fluid conduction capacity, electrical conductivity and thermal conductivity of the microneedle through the eccentric structural design of the needle rod and the center of the through hole, as well as the mixed design of the array, so that it can be used in pulse current therapy or pulse thermal moxibustion therapy, expanding its application range and significantly improving its therapeutic effect.

[0079] The microneedle array chip and the eccentric metal microneedles provided by the present invention have a unique eccentric design, a strong structure and will not break; the needle tip is sharp and easy to puncture; the maximum penetration depth of the microneedles is easy to adjust and control; the microneedles in the array have good consistency and are safe and reliable to use; the hollow microneedles have side openings, which can effectively avoid the phenomenon of skin blocking the infusion hole and avoid the drug overflowing to the outside of the skin to cause drug solution waste and treatment environment pollution; when subcutaneous injection and pulse current and pulse heat therapy are used for combined treatment, it is more conducive to the rapid diffusion and absorption of the drug to improve the efficacy.

[0080] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, technical features that are the same or similar to those of the above-mentioned embodiments of the present invention are within the protection scope of the present invention.

Claims

1. A capillary hollow metal microneedle, characterized in that: It is an eccentric capillary hollow metal microneedle, which includes a cylindrical metal needle rod and a needle tip arranged at the front section of the needle rod, the upper surface of the needle tip is an elliptical plane section inclined at an acute angle to the axis of the needle rod, the top of the upper surface is a pointed top, and the bottom is a pointed bottom; the inside of the needle rod is provided with a cylindrical through hole that passes through from top to bottom along the length direction to form a hollow structure, the needle rod and the axial center of the through hole are eccentric, the axis of the through hole is translated to the side of the pointed bottom to a set distance, so that the wall thickness of the needle rod near the pointed top is not less than 1.2 times the wall thickness of the needle rod near the pointed bottom, so as to significantly improve the axial strength and electrical and thermal conductivity of the wall of the needle rod near the pointed top; The upper surface of the needle tip is set at an acute angle of 15 to 45° with respect to the axis of the needle bar; Assuming that the diameter of the needle rod is D1, the diameter of the through hole is D2, the wall thickness of the needle rod near the tip is T1, and the wall thickness of the needle rod near the tip is T2, then: T1≥(D1-D2)*6 / 11 (Formula 1), T2≤(D1-D2)*5 / 11 (Formula 2), Assuming that the distance between the needle bar and the axis of the through hole, that is, the distance between the two centers of the circle is L, then: L = (D1-D2) / 2-T2 (Formula 3).

2. A capillary hollow metal microneedle according to claim 1, characterized in that: The value range of D1 is 0.5 to 150 microns, the diameter D2 of the through hole is 0.2 to 100 microns, and the height is 50 to 1000 microns.

3. A capillary hollow metal microneedle according to claim 1, characterized in that: The cylindrical metal needle rod is a conical column that is wide at the bottom and narrow at the top, with a bottom diameter D3 of 20 to 30 microns, a top diameter D1 of 0.5 to 10 microns, a through hole diameter D2 of 0.2 to 5 microns, and a height of 50 to 500 microns.

4. The capillary hollow metal microneedle according to claim 1, characterized in that: The tip bottom of the needle tip is also provided with a lateral opening which is communicated with the through hole and extends toward the needle rod.

5. An array chip using the capillary hollow metal microneedles according to any one of claims 1 to 4, characterized in that: The invention comprises a plurality of eccentric capillary hollow metal microneedles and an equilateral substrate. The bottoms of the microneedles are arranged on the substrate in a rectangular array, and the upper parts are mutually parallel to form a microneedle array. The inclination direction of the elliptical plane section on the upper surface of each microneedle tip is toward the geometric center of the substrate, so that the through-hole section on each microneedle tip is centered on the geometric center point of the substrate, is centrally symmetrical, and is distributed at equal distances. The distance between the centers of the microneedles is 100 to 300 microns.

6. The array chip according to claim 5, characterized in that: The outer contours of the substrate and the array are rectangular, circular, triangular or regular hexagonal.

7. The array chip according to claim 5, characterized in that: Each microneedle in the array includes an eccentric capillary hollow metal microneedle, a non-eccentric capillary hollow metal microneedle and a solid capillary metal microneedle, and the inclination direction of the elliptical plane section on the upper surface of the needle tip of each eccentric capillary hollow metal microneedle is toward the geometric center of the substrate, so that the through-hole section on each needle tip is centered on the geometric center point of the carrier, is centrally symmetrical, and is distributed at equal distances; the eccentric capillary hollow metal microneedles, the non-eccentric capillary hollow metal microneedles and the solid capillary metal microneedles are arranged and combined in a set manner to implement local treatment.

8. An application of the array chip according to any one of claims 5 to 7, characterized in that: A plurality of array chips are arranged on a carrier to form a treatment unit including the plurality of array chips, which is further made into a subcutaneous treatment device; and the subcutaneous treatment device is further made into a subcutaneous drug, electricity or heat treatment or beauty device.

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