阅读说明：本技术 基于柔性衬底的微针阵列干电极及其制备方法 (Microneedle array dry electrode based on flexible substrate and preparation method thereof ) 是由 鲁道欢 李娟� 于 2019-08-28 设计创作，主要内容包括：本发明公开了基于柔性衬底的微针阵列干电极及其制备方法,方法包括：将金属微针的针尖朝下插入在设置有互不相连的多个微通孔的基底上,形成微针阵列；将排布好的微针阵列的针尖朝上放入凹槽中,并将导电预聚体加入所述凹槽中固化成型为柔性导电衬底；将带有微通孔的基底从导电微针阵列上分离,得到基于柔性衬底的微针阵列干电极。本发明的微针阵列干电极包括金属微针电极阵列以及柔性导电衬底,本发明将柔性导电衬底与金属微针结合起来,制备成微针干电极；该制备方法简单、成本低、微针电极强度高,安全性好,利于实现长时高效的信号采集,可广泛应用于医疗器械技术领域。(The invention discloses a microneedle array dry electrode based on a flexible substrate and a preparation method thereof, wherein the method comprises the following steps: inserting a metal microneedle with a needle point facing downwards on a substrate provided with a plurality of unconnected micro through holes to form a microneedle array; placing the arranged microneedle array with the needle tips facing upwards into the groove, adding a conductive prepolymer into the groove, and curing and molding to form a flexible conductive substrate; and separating the substrate with the micro through holes from the conductive micro-needle array to obtain the micro-needle array dry electrode based on the flexible substrate. The micro-needle array dry electrode comprises a metal micro-needle electrode array and a flexible conductive substrate, wherein the flexible conductive substrate is combined with a metal micro-needle to prepare the micro-needle dry electrode; the preparation method is simple, low in cost, high in microneedle electrode strength, good in safety, beneficial to realizing long-term and efficient signal acquisition, and widely applicable to the technical field of medical instruments.)

1. The microneedle array dry electrode based on the flexible substrate is characterized in that: the flexible conductive micro-needle comprises a metal micro-needle electrode array and a flexible conductive substrate, wherein the metal micro-needle comprises a needle body and a needle point; the needle body of the metal micro-needle is implanted into the flexible conductive substrate; the needle tip part of the metal micro-needle is exposed on the surface of the flexible conductive substrate; the needle body of the metal micro-needle is embedded in the flexible conductive substrate, and the needle body of the metal micro-needle is electrically connected with the flexible conductive substrate.

2. A microneedle array dry electrode based on a flexible substrate as claimed in claim 1, characterized in that: the height of the needle tip of the metal microneedle exposed out of the flexible conductive substrate is 200 and 1000 mu m.

3. A microneedle array dry electrode based on a flexible substrate as claimed in claim 1, characterized in that: the array size of the metal microneedle array, the distance between the metal microneedles, the arrangement mode of the metal microneedles and the height of the needle points of the metal microneedles exposed out of the substrate can be adjusted.

4. The preparation method of the microneedle array dry electrode based on the flexible substrate is characterized by comprising the following steps: the method comprises the following steps:

inserting a metal microneedle with a needle point facing downwards on a substrate provided with a plurality of unconnected micro through holes to form a microneedle array;

placing the arranged microneedle array with the needle tips facing upwards into the groove, adding a conductive prepolymer into the groove, and curing and molding to form a flexible conductive substrate; the needle body of the metal micro-needle is fixed in the flexible conductive substrate, and the needle body of the metal micro-needle is electrically connected with the flexible conductive substrate;

and separating the substrate with the micro through holes from the conductive micro-needle array to obtain the micro-needle array dry electrode based on the flexible substrate.

5. The method for preparing a microneedle array dry electrode based on a flexible substrate according to claim 4, wherein: the substrate with the micro-vias may be a flexible substrate or a rigid substrate.

6. The method for preparing a microneedle array dry electrode based on a flexible substrate according to claim 4, wherein: the substrate thickness is less than the length of the metallic microneedles.

7. The method for preparing a microneedle array dry electrode based on a flexible substrate according to claim 4, wherein: the needle point of the metal micro-needle penetrates through the micro-through hole of the substrate.

8. The method for preparing a microneedle array dry electrode based on a flexible substrate according to claim 4, wherein: the needle point of the metal microneedle is flush with the upper surface of the substrate or is exposed out of the upper surface of the substrate.

9. The method for preparing a microneedle array dry electrode based on a flexible substrate according to claim 8, wherein: the exposed lengths of the needle points of the metal microneedles are the same or different; the needle body part of the metal micro-needle is wholly or partially remained outside the substrate.

10. The method for preparing a microneedle array dry electrode based on a flexible substrate according to claim 4, wherein: the conductive prepolymer is a mixed solution of a conductive filler and a high-molecular polymer solution, the conductive prepolymer added into the groove submerges the needle bodies of the metal microneedles, and the liquid level of the conductive prepolymer does not exceed the lower surface of the substrate.

Technical Field

The invention relates to the technical field of medical instruments, in particular to a microneedle array dry electrode based on a flexible substrate and a preparation method thereof.

Background

The physiological electric signals mainly comprise myoelectricity, electrocardio, electroencephalogram, electrooculogram and other signals, can directly reflect the physical health condition of people, and have an important position in the aspect of medical diagnosis. Is the basis of main monitored objects and physiological indexes in the clinical medical diagnosis process, and has important guiding significance for the diagnosis and treatment of clinical diseases such as cardiovascular and cerebrovascular diseases, muscle dysfunction and the like. The physiological electric signals belong to weak electric signals, and are about 1-100 mu V especially for electrocardio signals, so that the electrocardio signals are easily influenced by noise, motion and the like in the measurement process. Therefore, the biomedical electrode for recording biopotential is a key device for determining signal quality, and how to better collect and monitor bioelectric signals becomes a hot spot of domestic and foreign research in recent years.

In the traditional physiological electric signal acquisition system, a wet electrode or a non-contact dry electrode is utilized, so that certain limitation exists. Before the wet electrode is used, the skin needs to be abraded and the conductive gel needs to be used, the preparation of the skin is time-consuming, inconvenient and short in continuous use time, and the use of the conductive gel is easy to stimulate the skin and cause allergy. Although the non-contact electrode does not use conductive gel, the non-contact electrode cannot penetrate through the stratum corneum of the skin, so that the non-contact electrode is easily interfered by skin impedance and influences the signal acquisition precision. The micro-needle dry electrode does not need conductive gel, and the needle electrode can painlessly puncture the cuticle and penetrate into the conductive epidermis (hair growth layer), so that the electrode-skin impedance is reduced, and the defects of the traditional bioelectrode are overcome. Compared with the traditional bioelectrode, the microneedle dry electrode can reduce the contact impedance between the electrode and the skin, does not need skin preparation and conductive gel, and can realize continuous, long-term and efficient physiological electric signal monitoring. Accordingly, microneedle dry electrodes have received increasingly extensive research and attention.

With the increasing application of the microneedle dry electrode in the aspect of recording physiological electric signals, the safety, effectiveness and comfort of the microneedle dry electrode are gradually paid attention. The microneedle dry electrode currently studied generally uses silicon, metal, polymer, etc. Although the Si microneedle is developed earlier and the manufacturing process is mature, the Si material is brittle and is easy to break when penetrating into the skin, so that certain potential safety hazards exist. Compared with Si microneedles, the polymer microneedles are simpler in preparation process and lower in cost, but the strength of the polymer microneedles is far lower than that of the Si microneedles or the metal microneedles, and the polymer microneedles are broken in the using process. Thus, microneedle dry electrodes are beginning to gradually develop toward metal microneedles. In addition, most of the microneedle dry electrodes prepared at present are rigid substrates, cannot be well attached to human skin, and the electrodes move and rub against the skin in the measurement process, so that motion artifacts are introduced into acquired electric signals. The invention patent of the prior art (with the patent application number of CN201910027078.5) discloses a flexible microneedle electrode array device and a preparation method, wherein a flexible substrate and a flexible microneedle electrode in the technology are made of polyimide with the same material, but polymer microneedles are lower in strength compared with metal microneedles and are not easy to penetrate through the skin.

Disclosure of Invention

In view of this, embodiments of the present invention provide a microneedle array dry electrode based on a flexible substrate with low cost and high microneedle strength, and a method for manufacturing the same.

In one aspect, the embodiment of the invention provides a microneedle array dry electrode based on a flexible substrate, which comprises a metal microneedle electrode array and a flexible conductive substrate, wherein the metal microneedle comprises a needle body and a needle point; the needle body of the metal micro-needle is implanted into the flexible conductive substrate; the needle tip part of the metal micro-needle is exposed on the surface of the flexible conductive substrate; the needle body of the metal micro-needle is embedded in the flexible conductive substrate, and the needle body of the metal micro-needle is electrically connected with the flexible conductive substrate.

Further, the height of the needle tip of the metal microneedle exposed out of the flexible conductive substrate is 200-1000 μm.

Furthermore, the array size of the metal microneedle array, the distance between the metal microneedles, the arrangement mode of the metal microneedles and the height of the needle points of the metal microneedles exposed out of the substrate can be adjusted.

On the other hand, the embodiment of the invention also provides a preparation method of the microneedle array dry electrode based on the flexible substrate, which comprises the following steps:

inserting a metal microneedle with a needle point facing downwards on a substrate provided with a plurality of unconnected micro through holes to form a microneedle array;

placing the arranged microneedle array with the needle tips facing upwards into the groove, adding a conductive prepolymer into the groove, and curing and molding to form a flexible conductive substrate; the needle body of the metal micro-needle is fixed in the flexible conductive substrate, and the needle body of the metal micro-needle is electrically connected with the flexible conductive substrate;

and separating the substrate with the micro through holes from the conductive micro-needle array to obtain the micro-needle array dry electrode based on the flexible substrate.

Further, the substrate with the micro-via may be a flexible substrate or a rigid substrate.

Further, the substrate thickness is less than the length of the metallic microneedles.

Further, the needle tip of the metal microneedle penetrates through the micro through hole of the substrate.

Further, the needle point of the metal microneedle is flush with or exposed out of the upper surface of the substrate.

Further, the exposed lengths of the needle points of the metal microneedles are the same or different; the needle body part of the metal micro-needle is wholly or partially remained outside the substrate.

Further, the conductive prepolymer is a mixed solution of a conductive filler and a high molecular polymer solution, the conductive prepolymer added into the groove submerges the needle bodies of the metal microneedles, and the liquid level of the conductive prepolymer does not exceed the lower surface of the substrate.

One or more of the above-described embodiments of the present invention have the following advantages: the micro-needle array dry electrode comprises a metal micro-needle electrode array and a flexible conductive substrate, wherein the flexible conductive substrate and a metal micro-needle are combined to prepare the micro-needle dry electrode; the preparation method is simple, low in cost, high in microneedle electrode strength and good in safety.

Further, the array size of the metal microneedle array, the distance between the metal microneedles, the arrangement mode of the metal microneedles and the height of the needle points of the metal microneedles exposed out of the substrate can be adjusted, namely, the arrangement mode of the microneedle array, the height of the microneedles and the like can be flexibly adjusted according to different skin parts acted by the electrodes so as to achieve good fit between the electrodes and the skin.

Drawings

FIG. 1 is a schematic view of a PDMS substrate according to example 1 of the present invention;

fig. 2 is a schematic structural view of a metallic microneedle according to example 1 of the present invention;

fig. 3 is a schematic structural view of a metallic microneedle insertion substrate according to example 1 of the present invention;

FIG. 4 is a schematic structural view of a flexible substrate according to embodiment 1 of the present invention;

fig. 5 is a schematic diagram of a flexible substrate-based microneedle array dry electrode according to example 1 of the present invention;

FIG. 6 is a schematic view of a substrate with micro-vias according to example 2 of the present invention;

fig. 7 is a schematic diagram of a flexible substrate-based microneedle array dry electrode according to example 2 of the present invention;

fig. 8 is a schematic view of a microneedle electrode according to example 3 of the present invention;

FIG. 9 is a flowchart illustrating the overall steps of the present invention.

Detailed Description

The invention will be further explained and explained with reference to the drawings and the embodiments in the description. The step numbers in the embodiments of the present invention are set for convenience of illustration only, the order between the steps is not limited at all, and the execution order of each step in the embodiments can be adaptively adjusted according to the understanding of those skilled in the art.