CN217793074U

CN217793074U - Flexible micro-needle structure

Info

Publication number: CN217793074U
Application number: CN202220393390.3U
Authority: CN
Inventors: 黄立; 黄晟; 王凡; 陈志刚
Original assignee: Wuhan Zhonghua Brain Computer Integration Technology Development Co Ltd
Current assignee: Wuhan Zhonghua Brain Computer Integration Technology Development Co Ltd
Priority date: 2022-02-25
Filing date: 2022-02-25
Publication date: 2022-11-15
Anticipated expiration: 2032-02-25

Abstract

The application discloses a flexible micro-needle which is used for being implanted into human tissue or animal tissue, and comprises at least one micro-needle body and at least one integrated circuit chip, wherein the integrated circuit chip is electrically connected with the micro-needle body; the micro needle body is rigid in a first direction along the length direction of the micro needle body, and the micro needle body is flexible in a second direction. The flexible micropin of this application has fully considered vascular flexible deformation, the rigidity micropin of traditional all-round rigidity has been abandoned, do not adopt all-round flexible micropin yet, but set up the micropin body to be the rigidity along its length direction's first direction, set up the second direction that is on a parallel with the first direction to flexibility, make it both can maintain certain intensity, so that implant in human or animal tissue, can guarantee certain flexibility again, make it can carry out the adaptability according to vascular flexible state and warp, reduce implantation nature damage.

Description

Flexible micro-needle structure

Technical Field

The present application relates to the field of microelectrodes. More particularly, the present application relates to a flexible microneedle structure.

Background

Microelectrode means an electrode with at least one dimension of the electrode being of micrometer or nanometer scale (i.e. <100 micrometer). Has been widely used in the fields of analytical chemistry, medical research, and the like.

Various physiological functions of human and animals are directly or indirectly regulated and controlled by a neural network in the brain, and recording the discharge frequency change of a single neuron requires a microelectrode to acquire a stronger electric signal and carry out long-time observation and research. Among them, microelectrodes implantable for long-term use in the Central Nervous System (CNS) have a wide range of applications.

The common microelectrode comprises metal and glass, the metal microelectrode is a high-strength metal fine needle, and the part except the tip is insulated by paint or glass. The metal electrode wire is formed by electrolytic corrosion of stainless steel, platinum-iridium alloy or tungsten carbide wire in an acid solution, various finished products can be selected, and the metal electrode wire has the defect that the geometric shape and the insulation state of the microelectrode are difficult to keep consistent. The glass microelectrode is drawn by a user with a rigid capillary tube as required. When the probe is used for measuring the resting potential and the action potential in the cell, the tip of the probe needs to be less than 0.5 micrometer; for measuring the potential of the inactive site of the extracellular active region, the tip may be 1-5 microns.

The micro-needles of the two micro-electrodes are rigid micro-needles, and cannot be deformed adaptively along with the expansion and contraction of blood vessels when being implanted, so that human tissues or animal tissues are easily damaged.

At present, researches on micro-needles of micro-electrodes on the market mainly focus on the application and the preparation method thereof, and little researches on the rigidity performance of the micro-needles are carried out, and how to reduce the damage of the micro-needles when the micro-needles are implanted into human tissues or animal tissues is not involved.

Therefore, it is highly desirable to develop a microneedle which causes less damage when implanted into human tissue or animal tissue.

Disclosure of Invention

To achieve these objects and other advantages in accordance with the purpose of the present application, in one aspect, a preferred embodiment of the present application provides a flexible microneedle for implantation into human or animal tissue, the flexible microneedle comprising at least one microneedle body; the micro needle body is rigid in a first direction along the length direction of the micro needle body, the micro needle body is flexible in a second direction, and the second direction is inclined to the first direction, or the second direction is perpendicular to the first direction.

Furthermore, at least one slit is arranged on the micro needle body; when the micro needle body is provided with at least two slits, the slits are arranged at intervals along the first direction, the two adjacent slits are staggered, and the slits are perpendicular to or inclined to the first direction.

Further, the projections of two adjacent slits in the first direction at least partially overlap.

Furthermore, one end of the slit penetrates through one side of the substrate, and the other end of the slit does not penetrate through the other side of the substrate.

Furthermore, both ends of the slit do not penetrate through both side edges of the substrate.

Further, the slit is filled with a biocompatible material, and the biocompatible material is degradable.

Furthermore, each micro needle body is provided with at least one body electrode point, and the body electrode points are used for collecting nerve signals.

Further, the integrated circuit chip is electrically connected with the micro needle body, the integrated circuit chip is bonded with the tail part of the micro needle body to form electric connection, and the integrated circuit chip receives, analyzes and processes the neural signals acquired by the body electrode points.

Further, the forming material of the micro needle body comprises silicon, polyimide, PDMS or bacterial cellulose.

Further, the micro-needle body is coated with biodegradable films, and the biodegradable films are used for balancing the stress of different regions of the micro-needle body.

The application at least comprises the following beneficial effects:

the utility model provides a flexible micropin has fully considered vascular flexible deformation, traditional all-round rigid's rigidity micropin has been abandoned, do not adopt all-round flexible micropin yet, but set up the micropin body into the first direction along its length direction for the rigidity, set up the second direction that is not on a parallel with the first direction into flexible, make it both can maintain certain intensity, so that implant in human or animal tissue, can guarantee certain flexibility again, make it can carry out the adaptability according to vascular flexible state and warp, reduce implantation nature damage.

Additional advantages, objects, and features of the application will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the application.

Drawings

Fig. 1 is a schematic structural view of a flexible microneedle according to an embodiment of the present application.

Fig. 2 is a schematic structural diagram of a microneedle body according to an embodiment of the present application.

Fig. 3 is a schematic view of a microneedle body according to another embodiment of the present application.

Detailed Description

The present application is described in further detail below with reference to the attached drawings so that those skilled in the art can implement the invention by referring to the description.

The following description is presented to disclose the application and to enable any person skilled in the art to practice the application. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art. The underlying principles of the application, as defined in the following description, may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the application.

It will be understood by those skilled in the art that in the present disclosure, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for ease of description and simplicity of description, and do not indicate or imply that the referenced devices or components must be constructed and operated in a particular orientation and thus are not to be considered limiting.

It is understood that the terms "a" and "an" should be interpreted as meaning that a number of one element or element is one in one embodiment, while a number of other elements is one in another embodiment, and the terms "a" and "an" should not be interpreted as limiting the number.

In view of the fact that the microneedles on the market at present are all traditional rigid microneedles, when the microneedles are implanted into human tissues or animal tissues, the microneedles cannot be deformed adaptively along with the expansion and contraction of blood vessels, and accordingly implantation damage is caused.

In order to overcome the above problems, a preferred embodiment of the present application provides a flexible microneedle for implantation into human or animal body tissue, as shown in fig. 1 to 3, the flexible microneedle comprising at least one microneedle body 1 and at least one integrated circuit chip 2, the integrated circuit chip 2 being electrically connected to the microneedle body 1; each micro needle body 1 is provided with at least one body electrode point, and the body electrode points are used for collecting nerve signals. The integrated circuit chip 2 receives, analyzes and processes the neural signals collected by the body electrode points.

The micro needle body 1 is rigid in a first direction along the length direction of the micro needle body, the micro needle body 1 is flexible in a second direction, and the second direction is inclined to the first direction, or the second direction is perpendicular to the first direction.

Above-mentioned micro needle body 1 sets up to the rigidity along its length direction's first direction for make micro needle body 1 possess certain rigidity like this, can be convenient for like this the operator implant micro needle body 1 in human or animal's soft tissue, and in order to overcome traditional all-round rigid micro needle and implant the harm that causes human soft tissue or animal soft tissue, therefore above-mentioned embodiment sets up micro needle body 1's second direction to flexibility, the second direction slope is in the first direction, or, the second direction perpendicular to first direction, in other words, the second direction is not parallel to first direction, and the flexible deformation of second direction has the embodiment at the length direction and the width direction of micro needle body this moment, is convenient for micro needle body suitable deformation along with the flexible state of blood vessel.

Considering that the traditional integrated circuit chip 2 and the micro pin body 1 are connected by a wire, the information collected by the micro pin body can be transmitted to the integrated circuit chip by an electric wire, the transmission speed is low, and the efficiency is low, therefore, in some embodiments of the application, the following improvement is carried out, the integrated circuit chip 2 and the tail part of the micro pin body 1 are bonded to form electric connection between the integrated circuit chip and the micro pin body, the transmission path of the information is reduced, and the information transmission efficiency is improved.

A preferred embodiment of the present application provides a specific structure of the micro needle body, realizes that the micro needle body 1 is rigid in the first direction along its length direction, the micro needle body 1 is flexible in the second direction, the flexible micro needle in, the micro needle body 1 includes the base plate 110 and distributes a plurality of slits 120 on the base plate, a plurality of slits 120 along the first direction interval sets up, staggers the setting between two adjacent slits 120, just the slit 120 perpendicular or inclined to the first direction. The slit 120 may be perpendicular to the length direction of the microneedle body (i.e. the first direction), or may be oblique to the length direction of the microneedle body, and the slit 120 disposed on the substrate may reduce the rigidity of the entire microneedle body 1 to a certain extent, but the size of the slit 120 needs to be controlled within a certain range, which is not too large, otherwise the rigidity of the microneedle body is reduced too much, which causes implantation difficulty, and is not too small, otherwise the flexibility is insufficient.

Here, the shape of the slit is not particularly limited, and may be a long strip, a wave, a zigzag, or the like.

The slit may be penetrated or not penetrated along the thickness direction of the substrate, and specifically, the penetration or not penetration may be determined according to actual conditions, and is not specifically limited herein, generally, under the penetration condition, the overall flexibility is stronger, under the non-penetration condition, the flexibility is weakened to a certain extent, and the rigidity is enhanced.

Considering that, normally, the material in the middle of the rigid substrate is the position that is least likely to deform under external stretching and compressing, the following design is made, and the projection between two adjacent slits 120 in the first direction at least partially overlaps, so that the flexibility of the material in the middle of the rigid substrate can be improved, and the flexibility of the micro-needle body in the second direction can be further improved.

In one embodiment, a slit penetrates through a side of a substrate, one end of the slit penetrates through one side of the substrate, and the other end of the slit does not penetrate through the other side of the substrate, for example, in two adjacent slits 120, one end of one slit 120 penetrates through one side of the substrate, and the other end of the slit does not penetrate through the other side of the substrate, and one end of the other slit 120 penetrates through the other side of the substrate 110, and the other end of the slit does not penetrate through one side of the substrate 110. The micro needle body with the structure reduces the restriction of the rigid material on the side edge, so that the rigid material has stronger flexibility in the second direction, and under the condition, the micro needle body 1 can deform adaptively according to the expansion state of the blood vessel, and the implantation damage is reduced.

In another embodiment, a case where the slit does not penetrate through the side edge of the substrate is provided, specifically, both ends of the slit do not penetrate through both side edges of the substrate, in this case, it is preferable that the sum of the lengths of two adjacent slits is greater than the width of the substrate, so that the flexibility can be further enhanced.

According to a preferred embodiment of the present application, in the flexible microneedle, the microneedle body 1 is made of a rigid material, which provides a base strength for the microneedle body, and ensures that the microneedle body can be implanted into the soft tissue of a human body or an animal. For example, silicon material can be used to fabricate the micro-needle body.

Because the rigidity of the silicon material is higher, after the micro needle body made of the material is provided with the slit, the micro needle body is easy to break. To avoid the foregoing, in other embodiments, the microneedle body is made of a material with a slightly lower rigidity, such as polyimide, PDMS, or bacterial cellulose.

In one practical scenario, the slit 120 may be filled with a biocompatible material, which is degradable. In the process of implanting the micro needle body into the target part, because the slit is filled with the biocompatible material, the rigidity of the micro needle body in the first direction can be enhanced, after the micro needle body is implanted into the target part, the biocompatible material can be degraded after a period of time (about 30 minutes), the material in the slit is released, the flexibility of the micro needle body in the second direction can be enhanced, and the micro needle body can be adaptively deformed according to the expansion state of a blood vessel, so that the implantation damage is reduced.

In a practical application scenario, due to the difference in the size of the slit, the stress levels of the regions of the microneedle body are not completely the same, and in practical use, under the same acting force, the region with higher stress may not deform, the flexibility of the microneedle body is poor, and the region with lower stress may deform excessively and break. Wherein, the biodegradable film can be coated on the whole surface of the micro needle body (including the slit), and the biodegradable film can also be coated only on the place outside the slit.

In this embodiment, the stress of the slits can be determined according to the area of the single region between the slits, and the biodegradable film is coated according to the stress difference of each region, specifically, the larger the area of the single region is, the larger the corresponding stress is, and the thinner the coated biodegradable film is; the smaller the area of the individual regions, the lower the corresponding stress, and the thinner and thicker the coated biodegradable film. Wherein the biodegradable film may be coated by a hot-melt coating process.

Wherein the biodegradable film comprises biodegradable polyester and/or copolyester and/or starch-based material, and the thickness of the biodegradable film is less than 20 μm.

In another aspect, a preferred embodiment of the present application provides a method for preparing the flexible microneedle, including the steps of:

step S1, micro needle body preparation:

forming a slit mask pattern on the substrate, exposing, transferring the slit mask pattern to the photoresist, selectively etching, and reserving the region covered by the photoresist layer to obtain a micro-needle body,

the etching solution used for etching comprises the water-soluble acid, and specifically comprises a combined acid mode of collocation of a strong acid and a weak acid, or the weak acid, wherein the strong acid is nitric acid or sulfuric acid, and the weak acid is at least one of phosphoric acid, HF acid, formic acid, acetic acid, citric acid, isocitric acid and glycolic acid. The strong acid and the weak acid are matched, so that the reaction speed can be slowed down, and the silicon-based surface structure is prevented from being influenced by the too high etching speed.

And S2, bonding the integrated circuit chip to the tail part of the micro pin body to form electric connection. The tail of the micro needle body is provided with a welding spot, the body electrode point is arranged close to the needle point of the micro needle body, and the body electrode point is connected with the corresponding welding spot through a connecting line, wherein the connecting line bypasses each slit.

While embodiments of the present application have been described above, it is not limited to the applications set forth in the description and the embodiments, which are fully applicable to a variety of fields suitable for this application, and it will be readily apparent to those skilled in the art that additional modifications may be made, and the application is not limited to the details shown and described herein, without departing from the general concept as defined by the claims and their equivalents.

Claims

1. A flexible microneedle for implantation in human or animal body tissue, comprising at least one microneedle body; the micro needle body is rigid in a first direction along the length direction of the micro needle body, the micro needle body is flexible in a second direction, and the second direction is inclined to the first direction, or the second direction is perpendicular to the first direction.

2. A flexible microneedle according to claim 1, wherein said microneedle body is provided with at least one slit; when the micro needle body is provided with at least two slits, the slits are arranged at intervals along the first direction, the two adjacent slits are staggered, and the slits are perpendicular to or inclined to the first direction.

3. A flexible microneedle according to claim 2, wherein projections of two adjacent slits in the first direction at least partially coincide.

4. A flexible microneedle according to claim 2, wherein one end of the slit extends through one side of the substrate, and the other end does not extend through the other side of the substrate.

5. A flexible microneedle according to claim 4, wherein both ends of said slit do not extend through both sides of said base plate.

6. A flexible microneedle according to claim 2, wherein said slit is filled with a biocompatible material, said biocompatible material being degradable.

7. A flexible microneedle according to any one of claims 1 to 6, wherein each of said microneedle bodies has at least one body electrode point for collecting a neural signal.

8. The flexible microneedle according to claim 7, further comprising at least one integrated circuit chip, wherein said integrated circuit chip is electrically connected to said microneedle body, said integrated circuit chip is bonded to the tail of said microneedle body to form an electrical connection, and said integrated circuit chip receives and analyzes the neural signals collected by said body electrode points.

9. A flexible microneedle according to any one of claims 1 to 6, wherein said microneedle body is coated with a biodegradable film for balancing the stresses in different regions of said microneedle body.