Microneedle capsule for delivering injection medicine and application of microneedle capsule

Abstract

The invention provides a microneedle capsule for delivering injection medicine and application thereof, and relates to the technical field of medicine, the microneedle capsule comprises a capsule, a power device arranged in the capsule and a plurality of injection microneedles located between the capsule and the power device; the power device comprises an elastic assembly and a limiting mechanism, and the elastic assembly corresponds to the multiple injection microneedles; the other end of the limiting mechanism is connected with the elastic component; the limiting mechanism is used for limiting the elastic component to be in a contraction state, and the limiting mechanism is made of a material which is degraded in the intestinal tract. The injection microneedle can be delivered to the intestinal tract through capsule wrapping, the limiting mechanism is degraded in the intestinal tract, the elastic assembly pushes the injection microneedle to move in the stretching direction of the elastic assembly, rushes out of the capsule and releases the injection microneedle, the released injection microneedle then penetrates through intestinal wall tissue, and injection medicine carried by the injection microneedle is injected into the intestinal wall tissue. The technical problem that in the prior art, injection drugs are difficult to take orally is solved.

Description

Technical Field

[0001] The present invention relates to the field of medical technology, and in particular to a microneedle capsule for delivering injectable drugs and application thereof. Background Art

[0002] There are several routes of drug administration, oral, intravenous (IV), intramuscular (IM), and subcutaneous (SC). Drugs can also be taken sublingually (sublingual), rectally (rectal), as eye drops, nasal sprays, oral sprays (inhalers), or applied topically (topically) or systemically (transdermally). Each route of administration has its own specific purpose and has its own advantages and disadvantages. However, drug developers and patients strongly prefer oral drugs over injectable drugs. For doctors, they prefer to prescribe oral drugs over injectable drugs, even if the effect is slightly worse. One reason is that patients usually don't like injections, and many medical disputes often evolve. In addition, patients have poor self-management ability for their diseases, and often "miss injections" or "repeated injections", both of which are very dangerous for diabetic patients with severe conditions. Therefore, the study of drug formulations and administration methods has always been an important goal in the field of drug research. It can be generally understood as changing drugs that currently require injections, such as biologics, to more convenient oral administration. However, oral administration is limited to drugs that can survive the acid environment of the stomach, the intestinal mucosa and epithelial barrier, and the enzymatic degradation of the intestine and liver. According to Lipinski's famous "Five Rules" (rules of thumb for judging whether a pharmacologically or biologically active compound can be an oral drug), oral drugs generally need to meet the following conditions, such as molecular weight is generally less than 500da, lipophilic, and without too many hydrogen bond donors or receptors. This makes it impossible to take proteins, genetic material or other macromolecules orally, so almost all biologics are administered by injection. Drug delivery researchers have been trying to take biologics and other high-molecular drugs orally for decades, but with little success.

[0003] In view of this, the present invention is proposed. Summary of the invention

[0004] One of the purposes of the present invention is to provide a microneedle capsule for delivering injectable drugs, so as to solve the technical problem in the prior art that injectable drugs are difficult to be administered orally.

[0005] The second object of the present invention is to provide the use of the above-mentioned microneedle capsule in delivering injectable drugs in the intestine.

[0006] In a first aspect, the present invention provides a microneedle capsule for delivering an injectable drug, comprising a capsule, a power device disposed in the capsule, and a plurality of injectable microneedles disposed between the capsule and the power device;

[0007] The power device comprises an elastic component and a limiting mechanism, wherein the elastic component is arranged correspondingly to a plurality of injection microneedles; one end of the limiting mechanism is connected to the capsule, and the other end is connected to the elastic component;

[0008] The limiting mechanism is used to limit the elastic component to a contracted state, and the limiting mechanism is composed of a material that degrades in the intestine.

[0009] Furthermore, the capsule is provided with a plurality of microneedle launching holes, and the plurality of microneedle launching holes correspond one-to-one to the plurality of injection microneedles respectively.

[0010] Furthermore, the injection end of the injection microneedle is placed in the microneedle launching hole, and the non-injection end is connected to the elastic component.

[0011] Furthermore, a stopper is provided in the microneedle emitting hole, the size of the stopper matches the size of the microneedle emitting hole, and the stopper is located above the injection microneedle;

[0012] Preferably, the stopper is composed of a material that degrades in the intestine;

[0013] Preferably, the thickness of the stopper is ≤ 1 / 2 of the depth of the microneedle emitting hole.

[0014] In an optional embodiment, a limiting film is further provided between the injection microneedle and the limiting plug, and the limiting film is used to limit the displacement of the injection microneedle along the microneedle launching hole in a direction away from the elastic component;

[0015] The limiting film includes any one of a polyester film, a polyvinyl alcohol film or a polyimide film.

[0016] Furthermore, the elastic force assembly includes a spring, two push plates arranged opposite to each other, and a plurality of push rods located on the push plates;

[0017] The two ends of the spring are respectively connected to two push plates arranged opposite to each other;

[0018] The push rod corresponds to the injection microneedle one by one;

[0019] The push plate is connected to the limiting mechanism, and one end of the limiting mechanism away from the push plate is connected to the capsule;

[0020] Partition plates are arranged on both sides of the push plate.

[0021] Furthermore, the limiting mechanism comprises a limiting plate, both ends of the push plate are respectively connected to the limiting plates, and one end of the limiting plate away from the push plate passes through the capsule.

[0022] Furthermore, the limiting mechanism includes a limiting plate and a limiting lace, the limiting plate is connected to the lower end of the push plate, the spring is connected to the limiting plate, a limiting groove is provided on the surface of the limiting plate opposite to the push plate, the limiting lace passes through the limiting groove on the limiting plate at one end of the spring, the lace hole at one end of the capsule, the limiting groove on the limiting plate at the other end of the spring and the lace hole at the other end of the capsule in sequence, and then the two ends are connected, the limiting lace and the limiting plate cooperate with each other to limit the spring to be in a contracted state.

[0023] Furthermore, a guide tube is provided in the direction in which the microneedle emission hole extends into the capsule, and the injection microneedle is located in the guide tube;

[0024] Preferably, the vertical distance between the end faces of the guide tube and the push plate opposite to each other is greater than or equal to the displacement distance of the injection microneedle completely out of the capsule.

[0025] Preferably, the injection microneedle is a hollow structure, and the hollow structure contains an injectable drug;

[0026] Preferably, the needle diameter of the injection microneedle is 10 to 100 μm;

[0027] Preferably, the length of the injection microneedle is 0.8 to 1.5 mm, preferably 1 mm.

[0028] Preferably, the injection microneedle comprises at least one of polylactic acid microneedle, polycaprolactone microneedle, chitosan microneedle, collagen microneedle, starch-based microneedle or cellulose microneedle;

[0029] Preferably, the size of the microneedle capsule is suitable for passing through the small intestine and filling the small intestine;

[0030] Preferably, the capsule comprises a supporting layer and an enteric layer, and the enteric layer is located on the inner side of the capsule.

[0031] In a second aspect, the present invention provides the use of the microneedle capsule described in any one of the aforementioned embodiments for delivering injectable drugs in the intestine;

[0032] Preferably, the injectable drug includes a drug preparation that is administered by injection;

[0033] Preferably, the injectable drugs include biological agents.

[0034] The present invention provides a microneedle capsule for delivering injectable drugs. The injectable microneedle can carry the injectable drug, which can be delivered to the intestine by being wrapped in a capsule. The limiting mechanism in the intestine degrades, thereby contacting the limiting effect of the elastic component. The elastic component is stretched by its own elastic force in the contracted state, thereby pushing the injectable microneedle to move along the stretching direction of the elastic component and rushing out of the capsule, thereby achieving the purpose of releasing the injectable microneedle. The released injectable microneedle then penetrates the intestinal wall tissue and injects the injectable drug it carries into the intestinal wall tissue. The technical problem that injectable drugs are difficult to be administered orally in the prior art is solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 This is a schematic diagram of the overall structure of a microneedle capsule for delivering injectable drugs provided in Example 1 of the present invention;

[0037] Figure 2 A schematic side view of the structure of a microneedle capsule for delivering injectable drugs provided in Example 1 of the present invention;

[0038] Figure 3 for Figure 2 Schematic diagram of the cross-sectional structure along the AA direction;

[0039] Figure 4 A schematic diagram of the top view of the microneedle capsule for delivering injectable drugs provided in Example 1 of the present invention;

[0040] Figure 5 for Figure 4 Schematic diagram of the cross-sectional structure along the BB direction;

[0041] Figure 6 for Figure 5 The enlarged structural diagram at A in the middle;

[0042] Figure 7 A schematic diagram of the overall structure of a microneedle capsule for delivering injectable drugs provided in Example 2 of the present invention;

[0043] Figure 8 A schematic side view of the structure of a microneedle capsule for delivering injectable drugs provided in Example 2 of the present invention;

[0044] Fig. 9 for Figure 8 Schematic diagram of the cross-sectional structure in the CC direction;

[0045] Fig.10 This is a schematic diagram of the cross-sectional structure of a top view of a microneedle capsule for delivering injectable drugs provided in Example 2 of the present invention.

[0046] Icons: 10-capsule; 11-microneedle launching hole; 12-limiting plug; 13-limiting membrane; 14-guide tube; 15-support layer; 16-enteric layer;

[0047] 20-Microneedle injection;

[0048] 31-limiting mechanism; 311-limiting plate; 312-limiting lace; 313-limiting groove; 314-lace hole; 32-spring; 33-push plate; 34-push rod; 35-partition. DETAILED DESCRIPTION

[0049] Unless otherwise defined herein, scientific and technical terms used in conjunction with the present invention shall have the meanings commonly understood by those of ordinary skill in the art. The meaning and scope of the terms should be clear, however, in the case of any potential ambiguity, the definitions provided herein take precedence over any dictionary or external definitions. In this application, unless otherwise stated, the use of "or" means "and / or". In addition, the use of the term "including" and other forms is non-limiting.

[0050] The methods and techniques of the present invention are generally performed according to conventional methods well known in the art and as described in various general and more specific references that are cited and discussed throughout the present specification unless otherwise indicated.

[0051] In one aspect, the present invention provides a microneedle capsule for delivering an injectable drug, comprising a capsule 10, a power device disposed in the capsule 10, and a plurality of injection microneedles 20 disposed between the capsule 10 and the power device;

[0052] The power device includes an elastic component and a limiting mechanism 31, and the elastic component is arranged corresponding to a plurality of injection microneedles 20; one end of the limiting mechanism 31 is connected to the capsule 10, and the other end is connected to the elastic component;

[0053] The limiting mechanism 31 is used to limit the elastic component to a contracted state, and the limiting mechanism is composed of a material that degrades in the intestine.

[0054] The injection microneedle 20 can carry the injection drug, which can be delivered to the intestine by being wrapped in the capsule 10. The limiting mechanism 31 in the intestine degrades, thereby contacting the limiting effect on the elastic component. The elastic component is stretched by its own elastic force in the contracted state, thereby pushing the injection microneedle 20 to move along the stretching direction of the elastic component and rushing out of the capsule 10, thereby achieving the purpose of releasing the injection microneedle 20. The released injection microneedle 20 then penetrates the intestinal wall tissue and injects the injection drug it carries into the intestinal wall tissue. The technical problem that injectable drugs are difficult to be administered orally in the prior art is solved.

[0055] The power device corresponds to the positions of the injection microneedles 20. The capsule 10 can contain one group of power devices and the corresponding injection microneedles 20, or multiple groups of power devices and the corresponding injection microneedles 20.

[0056] The injection microneedle 20 is a hollow structure, in which an injectable drug is preset; the needle diameter of the injection microneedle 20 can be set to 10-100 μm; the length of the injection microneedle 20 can be set to 0.8-1.5 mm, preferably 1 mm.

[0057] The injection microneedle 20 includes at least one of polylactic acid microneedle, polycaprolactone microneedle, chitosan microneedle, collagen microneedle, starch-based microneedle or cellulose microneedle. After the injection of the preset drug is completed, the injection microneedle 20 can be degraded in the small intestine.

[0058] In order to avoid the situation that the release of the injection microneedles 20 is blocked due to the effect of the capsule 10, the microneedle launching holes 11 can be prefabricated on the capsule 10. In some specific embodiments, the capsule 10 is provided with a plurality of microneedle launching holes 11, and the plurality of microneedle launching holes 11 correspond to the plurality of injection microneedles 20 respectively.

[0059] In order to enable the injection microneedle 20 to be accurately released along the microneedle launching hole 11 to the outside of the capsule 10 during the release process, in some specific embodiments, the injection end of the injection microneedle 20 is placed in the microneedle launching hole 11, and the non-injection end is connected to the elastic component.

[0060] In some specific embodiments, a stopper 12 is provided in the microneedle launch hole 11, the size of the stopper 12 matches the size of the microneedle launch hole 11, and is located above the injection microneedle 20. The stopper can prevent tissue fluid from entering the capsule 10 along the microneedle launch hole before reaching the intestine.

[0061] When the microneedle capsule reaches the intestine, in order to prevent the stopper 12 from hindering the release of the injection microneedle 20, in some specific embodiments, the stopper 12 is made of a material that degrades in the intestine, and degrades in the intestinal environment to form a microneedle launch hole 11. The degradation speed of the stopper 12 is faster than the degradation speed of the stopper mechanism 31.

[0062] Experiments have found that the thickness of the stopper 12 affects its degradation time. In order not to affect the release of the injection microneedle, the thickness of the stopper 12 is ≤ 1 / 2 of the depth of the microneedle launching hole 11 to ensure that the microneedle launching hole 11 is in an unobstructed state when the limiting mechanism 31 releases the limiting effect.

[0063] In some specific embodiments, a limiting film 13 is further provided between the injection microneedle 20 and the limiting plug 12 , and the limiting film 13 is used to limit the displacement of the injection microneedle 20 along the microneedle launching hole 11 in a direction away from the elastic component.

[0064] Among them, when the limiting plug 12 degrades, the limiting membrane 13 is exposed to the intestinal environment. The limiting membrane 13 is a thin film material with good biocompatibility and is difficult to dissolve in the small intestine environment. It has a certain stability. The limiting membrane 13 can keep the position of the injection microneedle 20 relatively stable.

[0065] Specifically, the limiting film 13 can be selected from any one of polyester film, polyvinyl alcohol film or polyimide film, and other film materials with good biocompatibility and poor dissolution in the small intestine environment can also be selected.

[0066] In some specific embodiments, the elastic component includes a spring 32, two oppositely arranged push plates 33 and a plurality of push rods 34 located on the push plates 33; the two ends of the spring 32 are respectively connected to the two oppositely arranged push plates 33; the push rods 34 correspond one-to-one to the injection microneedles 20; the push plate 33 is connected to the limiting mechanism 31, and the end of the limiting mechanism 31 away from the push plate 33 is connected to the capsule 10.

[0067] The limiting mechanism 31 is connected to the capsule 10 to limit the push plate 33, so as to limit the spring 32 in a compressed state. When the limiting mechanism 31 connected to the capsule 10 is degraded, the limiting effect fails. During the extension of the spring 32, the push plate 33 is pushed, thereby driving the push rod 34 to move, so as to push the injection microneedle 20 in contact with the push rod to the outside of the capsule 10, and release the injection microneedle.

[0068] Wherein, the spring 32 is preferably a spring with two ends tapered, which can make it occupy less space in a compressed state and form a larger pushing distance. A spring with unchanged diameter can also be selected according to the situation to meet the pushing distance and force.

[0069] In some specific implementations, partitions 35 are provided on both sides of the push plate 33 to prevent the push plate 33 from being displaced and to enable the push plate 33 to move outward within a certain range.

[0070] In some specific embodiments, the limiting mechanism 31 includes a limiting plate 311 , both ends of the push plate 33 are respectively connected to the limiting plates 311 , and one end of the limiting plate 311 away from the push plate passes through the capsule 10 .

[0071] The limiting plate 311 is made of a material that degrades in the intestine. After penetrating the capsule 10 , the limiting plate 311 is exposed to the small intestine environment, degrades, and separates from the capsule 10 , thereby releasing its limiting effect on the push plate 33 .

[0072] In some specific embodiments, the limiting mechanism 31 includes a limiting plate 311 and a limiting lace 312, the limiting plate 311 is connected to the lower end of the push plate 33, the spring 32 is connected to the limiting plate 311, and a limiting groove 313 is provided on the surface of the limiting plate 311 opposite to the push plate 33, the limiting lace 312 passes through the limiting groove 313 on the limiting plate 311 at one end of the spring, the lace hole 314 at one end of the capsule 10, the limiting groove 313 on the limiting plate 311 at the other end of the spring and the lace hole 314 at the other end of the capsule 10 in sequence, and then the two ends are connected, the limiting lace 312 cooperates with the limiting plate 311 to limit the spring 32 to be in a contracted state. At this time, in order to keep the spring in a contracted state, the limiting lace 312 is in a tight state, and the limiting lace 312 located at the lace hole is partially exposed to the small intestine environment. The limiting lace 312 is composed of a material that degrades in the intestine, and degrades, causing the limiting lace 312 here to break, thereby releasing the tight state of the limiting lace 312 and releasing the limitation.

[0073] In some specific embodiments, a guide tube 14 is provided in the direction in which the microneedle emitting hole 11 extends into the capsule 10, and the injection microneedle 20 is located in the guide tube 14. The guide tube 14 is provided to guide the release path of the injection microneedle to ensure that it is released along a preset path.

[0074] In some specific embodiments, the vertical distance between the opposite end faces of the guide tube 14 and the push plate 33 is ≥ the displacement distance of the injection microneedle 20 completely out of the capsule 10 to ensure that the push rod can completely push the injection microneedle 20 to the outside of the capsule 10 to complete the release.

[0075] In some specific embodiments, the size of the microneedle capsule is suitable for passing through the small intestine and filling the small intestine; the injection microneedle for easy release penetrates the small intestinal wall tissue and injects the pre-set drug into the tissue.

[0076] In some specific embodiments, the capsule 10 includes a support layer 15 and an enteric layer 16, and the enteric layer 16 is located on the inner side of the capsule 10. The support layer 15 is composed of a material that is not decomposed by gastric acid and intestinal fluid, and the enteric layer is composed of a material that is not decomposed by gastric acid but is degradable in the small intestine environment. After the injection microneedle 20 is released, the small intestinal fluid will enter the capsule 10 along the degraded gap, causing the enteric layer 16 to degrade, making the capsule 10 smaller and easier to be discharged from the body.

[0077] Among them, each structure inside the capsule 10 can be composed of materials that are degradable in the intestine. Specifically, materials with different degradation rates can be selected in sequence according to the functions of each part. After the release is completed, the small intestinal fluid enters the capsule 10 and degrades, and finally the supporting layer 15 remains and is excreted from the body.

[0078] According to another aspect of the present invention, there is also provided the use of the above-mentioned microneedle capsule in delivering injectable drugs in the intestine;

[0079] Among them, the injectable drugs include drug preparations that are administered by injection; specific injectable drugs may include biological preparations, such as insulin.

[0080] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0081] Example 1

[0082] Combination Figure 1 to Figure 6 To illustrate, a microneedle capsule for delivering an injectable drug includes a capsule 10, a power device placed in the capsule 10, and an injection microneedle 20 located between the capsule 10 and the power device. In this embodiment, two groups of power devices and 36 corresponding injection microneedles 20 are provided, and the 36 corresponding injection microneedles 20 in each group are evenly arranged relative to each other. The capsule 10 includes a support layer 15 and an enteric layer 16, and the enteric layer 16 is located on the inner side of the capsule 10.

[0083] The power device comprises an elastic component and a limiting mechanism 31, and the limiting mechanism 31 is used to limit the elastic component to be in a contracted state.

[0084] The capsule 10 is provided with microneedle launching holes 11 corresponding to the injection microneedles 20 one by one, the injection end of the injection microneedle 20 is placed in the microneedle launching hole 11, and the non-injection end is connected to the elastic component. A stopper 12 is provided in the microneedle launching hole 11, the size of the stopper 12 matches the size of the microneedle launching hole 11, and is located above the injection microneedle 20; the stopper 12 is made of a material that degrades in the intestine; the thickness of the stopper 12 is 1 / 2 of the depth of the microneedle launching hole 11.

[0085] A limiting membrane 13 is also provided between the injection microneedle 20 and the limiting plug 12 .

[0086] The elastic component includes a spring 32, two push plates 33 arranged opposite to each other, and a plurality of push rods 34 located on the push plates 33; both ends of the spring 32 are respectively connected to the two push plates 33 arranged opposite to each other;

[0087] The push rods 34 correspond to the injection microneedles 20 one by one; partitions 35 are provided on both sides of the push plate 33 .

[0088] The limiting mechanism 31 includes a limiting plate 311 . Both ends of the push plate 33 are respectively connected to the limiting plates 311 . One end of the limiting plate 311 away from the push plate passes through the capsule 10 .

[0089] A guide tube 14 is provided in the direction of the microneedle emitting hole 11 extending into the capsule 10, and the injection microneedle 20 is located in the guide tube 14. The vertical distance between the end surfaces of the guide tube 14 and the push plate 33 facing each other is equal to the displacement distance of the injection microneedle 20 completely leaving the capsule 10.

[0090] The injection microneedle 20 is a hollow structure, in which the thymosin solution is pre-filled; the needle tip of the injection microneedle 20 has a diameter of 30 μm and a length of 1 mm.

[0091] In this embodiment, the size of the microneedle capsule is suitable for passing through the small intestine and filling the small intestine.

[0092] Example 2

[0093] Combination Figure 7 to Figure 10 To illustrate, unlike Example 1, the needle of the injection microneedle 20 is made of nearly 100% compressed freeze-dried insulin, which can penetrate the intestinal wall, dissolve the needle, and the remaining part of the capsule is discharged from the body through the intestine.

[0094] The limiting mechanism 31 includes a limiting plate 311 and a limiting lace 312, wherein the limiting plate 311 is connected to the lower end of the push plate 33, the spring 32 is connected to the limiting plate 311, and a limiting groove 313 is provided on the surface of the limiting plate 311 opposite to the push plate 33, the limiting lace 312 sequentially penetrates the limiting groove 313 on the limiting plate 311 at one end of the spring, the lace hole 314 at one end of the capsule 10, the limiting groove 313 on the limiting plate 311 at the other end of the spring, and the lace hole 314 at the other end of the capsule 10, and then the two ends are connected, and the limiting lace 312 cooperates with the limiting plate 311 to limit the spring 32 to a contracted state. The limiting lace 312 is composed of a material that degrades in the intestine.

[0095] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A microneedle capsule for delivering an injectable drug, characterized in that: It comprises a capsule (10), a power device placed in the capsule (10), and a plurality of injection microneedles (20) located between the capsule (10) and the power device; The power device comprises an elastic component and a limiting mechanism (31), wherein the elastic component is arranged corresponding to a plurality of injection microneedles (20); one end of the limiting mechanism (31) is connected to the capsule (10), and the other end is connected to the elastic component; The limiting mechanism (31) is used to limit the elastic component to a contracted state, and the limiting mechanism is composed of a material that degrades in the intestine.

2. The microneedle capsule according to claim 1, characterized in that The capsule (10) is provided with a plurality of microneedle emitting holes (11), and the plurality of microneedle emitting holes (11) correspond one-to-one to the plurality of injection microneedles (20), respectively.

3. The microneedle capsule according to claim 2, characterized in that: The injection end of the injection microneedle (20) is placed in the microneedle emission hole (11), and the non-injection end is connected to the elastic component.

4. The microneedle capsule according to claim 3, characterized in that A stopper (12) is provided in the microneedle emitting hole (11), the size of the stopper (12) matches the size of the microneedle emitting hole (11), and the stopper (12) is located above the injection microneedle (20); Preferably, the stopper (12) is made of a material that degrades in the intestine; Preferably, the thickness of the limiting plug (12) is ≤ 1 / 2 of the depth of the microneedle emitting hole (11).

5. The microneedle capsule according to claim 4, characterized in that: A limiting film (13) is also provided between the injection microneedle (20) and the limiting plug (12), and the limiting film (13) is used to limit the displacement of the injection microneedle (20) along the microneedle emission hole (11) in a direction away from the elastic component.

6. The microneedle capsule according to claim 5, characterized in that The elastic force component comprises a spring (32), two push plates (33) arranged opposite to each other, and a plurality of push rods (34) located on the push plates (33); The two ends of the spring (32) are respectively connected to two push plates (33) arranged opposite to each other; The push rod (34) corresponds one to one with the injection microneedle (20); The push plate (33) is connected to the limiting mechanism (31), and one end of the limiting mechanism (31) away from the push plate (33) is connected to the capsule (10); The push plate (33) is provided with partition plates (35) on both sides.

7. The microneedle capsule according to claim 6, characterized in that The limiting mechanism (31) comprises a limiting plate (311), and both ends of the push plate (33) are respectively connected to the limiting plate (311), and one end of the limiting plate (311) away from the push plate passes through the capsule (10).

8. The microneedle capsule according to claim 6, characterized in that The limiting mechanism (31) comprises a limiting plate (311) and a limiting lace (312), wherein the limiting plate (311) is connected to the lower end of the push plate (33), and the spring (32) is connected to the limiting plate (311). A limiting groove (313) is provided on the surface of the limiting plate (311) opposite to the push plate (33). The limiting lace (312) sequentially penetrates the limiting groove (313) on the limiting plate (311) at one end of the spring, the lace hole (314) at one end of the capsule (10), the limiting groove (313) on the limiting plate (311) at the other end of the spring, and the lace hole (314) at the other end of the capsule (10), and then the two ends are connected, and the limiting lace cooperates with the limiting plate to limit the spring (32) to be in a contracted state.

9. The microneedle capsule according to claim 7 or 8, characterized in that: A guide tube (14) is provided in the direction in which the microneedle emission hole (11) extends into the capsule (10), and the injection microneedle (20) is located in the guide tube (14); Preferably, the vertical distance between the end surfaces of the guide tube (14) and the push plate (33) facing each other is greater than or equal to the displacement distance of the injection microneedle (20) completely leaving the capsule (10); Preferably, the injection microneedle (20) is a hollow structure, and the hollow structure contains an injectable drug; Preferably, the needle diameter of the injection microneedle (20) is 10 to 100 μm; Preferably, the length of the injection microneedle (20) is 0.8 to 1.5 mm, preferably 1 mm; Preferably, the size of the microneedle capsule is suitable for passing through the small intestine and filling the small intestine; Preferably, the capsule (10) comprises a supporting layer (15) and an enteric layer (16), and the enteric layer (16) is located on the inner side of the capsule (10).

10. Use of the microneedle capsule according to any one of claims 1 to 9 for delivering injectable drugs in the intestine; Preferably, the injectable drug includes a drug preparation that is administered by injection; Preferably, the injectable drugs include biological agents.

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