Biocompatible gel electrode capable of inhibiting deformation signal crosstalk and preparation method thereof

Abstract

The invention discloses a biocompatible gel electrode capable of inhibiting deformation signal crosstalk and a preparation method of the biocompatible gel electrode. The skin electrode comprises a conductive layer composed of high-crystallinity polyvinyl alcohol PVA and MXene, a supporting layer located below the conductive layer and formed by compounding bacterial cellulose and tannic acid, and a gel layer located below the supporting layer and formed by compounding bacterial cellulose and tannic acid, the surface of the conductive layer and the surface of the supporting layer are provided with patterned lines formed by cutting through the nanosecond laser technology, and the patterned lines are used for reducing motion artifacts. The skin electrode has strong deformation resistance, motion artifacts in the signal detection process are effectively reduced, and the accuracy and reliability of signals are improved.

Description

Technical Field

[0001] The invention relates to the technical field of flexible electronic devices, and in particular to a biocompatible gel electrode capable of suppressing deformation signal crosstalk and a preparation method thereof. Background Art

[0002] With the development of medical health monitoring technology, skin electrodes, as an important biosignal acquisition tool, are widely used in the fields of electrocardiogram (ECG), electromyography (EMG), electrooculography (EOG) and electroencephalography (EEG). Traditional skin electrodes mainly use Ag / AgCl gel electrodes. Although they can provide good signal quality, they also have some significant defects. First, the gel electrode is easy to dry, resulting in a decrease in signal quality and cannot meet the needs of long-term monitoring. Secondly, the gel electrode has poor adhesion on the skin, especially when the skin is stretched or compressed, it is easy to produce displacement, causing serious motion artifacts, seriously affecting the accuracy and reliability of the signal. In terms of the structural strength of the electrode itself, the traditional single gel electrode has low structural strength and there is a mismatch between the mechanical behavior of the human body. During continuous wearing monitoring, the gel electrode is prone to fatigue, the signal volatility is large, and the accuracy is reduced.

[0003] In addition, traditional gel materials may cause irritation to the skin or trigger allergic reactions, limiting their application in sensitive people. Therefore, developing a new type of skin electrode that is biocompatible, has strong deformation resistance, and can significantly reduce motion artifacts has become an important research direction. Summary of the invention

[0004] 1. Technical Problems Solved

[0005] The technical problem to be solved by the present invention is the various problems mentioned in the above background technology, and provides a biocompatible gel electrode capable of suppressing deformation signal crosstalk and a preparation method thereof.

[0006] 2. Technical Solution

[0007] In order to solve the above technical problems, the technical solution provided by the present invention is: a biocompatible gel electrode capable of suppressing deformation signal crosstalk, characterized in that the skin electrode includes a conductive layer composed of high-crystallinity polyvinyl alcohol (PVA) and MXene, and a support layer formed by a composite of bacterial cellulose and tannic acid located below the conductive layer, the surfaces of the conductive layer and the support layer have patterned textures cut by nanosecond laser technology, and the patterned textures are used to reduce motion artifacts.

[0008] As an improvement, a method for preparing a biocompatible gel electrode capable of suppressing deformation signal crosstalk comprises the following steps:

[0009] S1. preparing MXene powder;

[0010] S2, preparing a composite support layer of bacterial cellulose and tannic acid;

[0011] S3, mixing MXene powder with PVA solution to form a conductive layer solution;

[0012] S4, applying the conductive layer solution on the support layer by a doctor blade method, and performing chemical treatment after in-situ cross-linking;

[0013] S5. Use nanosecond laser technology to perform anti-deformation structural treatment on the surfaces of the conductive layer and the support layer to form a skin electrode with patterned textures.

[0014] As an improvement, the MXene is prepared by the following steps:

[0015] a1. Dissolve lithium fluoride LiF in hydrochloric acid HCl solution and stir evenly;

[0016] a2. Add aluminum carbide Ti3AlC2 powder gradually into the above mixed solution, stir for 24 hours and centrifuge and wash until the pH value of the supernatant is greater than 6;

[0017] a3. After ice bath ultrasonic treatment and re-centrifugation, the product is freeze-dried to obtain a single-layer MXene powder. The re-centrifugation speed is preferably 3500 r min -1 .

[0018] As an improvement, the support layer is prepared by the following steps:

[0019] b1. Add tannic acid to the bacterial cellulose solution and adjust the pH to 8 using the prepared 1M tris solution. Stir for 24 hours and then filter and dry to form a film.

[0020] As an improvement, the conductive layer is prepared by the following steps:

[0021] c1. Disperse MXene powder in deionized water, add it to the PVA solution, and stir evenly to form a mixed solution. The preferred amount of the MXene powder is 0.5 g, and the preferred amount of the PVA solution is 20 mL;

[0022] c2. Apply the mixed solution on the support layer, dry it naturally, immerse it in 6M sodium hydroxide solution, and finally rinse it with deionized water.

[0023] As an improvement, the patterned design specifically includes grid, wavy line and dot matrix distribution, the purpose of which is to use the patterned texture to resist greater deformation, so as to reduce motion artifacts and reduce signal interference caused by motion.

[0024] As an improvement, the chemical treatment includes soaking the conductive layer in a 6M sodium hydroxide solution for 15 minutes and then rinsing it with deionized water.

[0025] 3. Beneficial Effects

[0026] The advantages of the present invention compared with the prior art are:

[0027] The present invention provides a biocompatible gel electrode capable of suppressing deformation signal crosstalk and a preparation method thereof. The skin electrode finally prepared has the following significant advantages: first, patterned lines are cut on the surfaces of the conductive layer and the support layer by nanosecond laser technology, so that the electrode has strong anti-deformation ability, effectively reduces motion artifacts in the signal detection process, and improves the accuracy and reliability of the signal; second, a specially treated polyvinyl alcohol (PVA), MXene, bacterial cellulose and tannic acid composite material is used, and the bacterial cellulose layer improves the overall strength, and can still maintain a signal stability after multiple bending. At the same time, the addition of the tannic acid composite material makes it skin-friendly, ensuring the biocompatibility of the electrode, performing well in cytotoxicity analysis, and being suitable for long-term wearing without causing skin irritation or allergic reaction; third, the skin electrode can still maintain good signal stability under long-term bending conditions, meeting the needs of long-term monitoring; finally, compared with commercial electrodes on the market and electrodes without special line designs, the skin electrode of the present invention can provide clearer and more stable signal output, greatly improving the quality and efficiency of electrophysiological signal monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The present invention discloses a biocompatible gel electrode capable of suppressing deformation signal crosstalk and a flow chart of its preparation method.

[0029] Figure 2 The present invention is a structural diagram of a biocompatible gel electrode capable of suppressing deformation signal crosstalk.

[0030] Figure 3 It is a PVA gradient stretching data diagram of a biocompatible gel electrode capable of suppressing deformation signal crosstalk according to the present invention.

[0031] Figure 4 The present invention is a biocompatible gel electrode bacterial cellulose gradient stretching data diagram capable of suppressing deformation signal crosstalk.

[0032] Figure 5 The present invention discloses a stress-strain curve diagram of a biocompatible gel electrode PVA, bacterial cellulose and a composite film of the two capable of suppressing deformation signal crosstalk.

[0033] Figure 6This is a comparison chart of the maximum stress, elastic modulus and toughness of three membranes of a biocompatible gel electrode capable of suppressing deformation signal crosstalk in the present invention.

[0034] Figure 7 The figure is a comparison chart of signal monitoring data of a biocompatible gel electrode capable of suppressing deformation signal crosstalk and a commercial electrode of the present invention.

[0035] Figure 8 The figure is a comparison diagram of noise and signal-to-noise ratio between a biocompatible gel electrode capable of suppressing deformation signal crosstalk and a commercial electrode of the present invention. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0037] Embodiment 1

[0038] like Figure 2 As shown, a biocompatible gel electrode capable of suppressing deformation signal crosstalk, the skin electrode includes a conductive layer composed of polyvinyl alcohol (PVA) and MXene, and a support layer formed by a composite of bacterial cellulose and tannic acid located below the conductive layer. The surfaces of the conductive layer and the support layer have patterned lines cut by nanosecond laser technology to reduce motion artifacts. The design of the patterned lines includes grid, wavy lines and dot matrix distribution. The purpose is to resist greater deformation with the help of the patterned lines, so as to reduce motion artifacts and reduce signal interference caused by motion.

[0039] like Figure 1 As shown, a method for preparing a biocompatible gel electrode capable of suppressing deformation signal crosstalk comprises the following steps:

[0040] S1. Prepare MXene powder, wherein the MXene is prepared by the following steps:

[0041] a1. Dissolve lithium fluoride LiF in hydrochloric acid HCl solution and stir evenly;

[0042] a2. Add aluminum carbide Ti3AlC2 powder gradually into the above mixed solution, stir for 24 hours and centrifuge and wash until the pH value of the supernatant is greater than 6;

[0043] a3. After ice bath ultrasonic treatment and re-centrifugation, the product is freeze-dried to obtain a single-layer MXene powder. The re-centrifugation speed is preferably 3500 r min -1 .

[0044] S2. Prepare a support layer composed of bacterial cellulose and tannic acid, wherein the support layer is prepared by the following steps:

[0045] b1. Add tannic acid to the bacterial cellulose solution, adjust the pH value to 8, stir for 24 hours, and then filter and dry to form a film.

[0046] S3, mixing MXene powder with PVA solution to form a conductive layer solution, wherein the conductive layer is prepared by the following steps:

[0047] c1. Disperse MXene powder in deionized water, add it to the PVA solution, and stir evenly to form a mixed solution. The preferred amount of the MXene powder is 0.5 g, and the preferred amount of the PVA solution is 20 mL;

[0048] c2. Apply the mixed solution on the support layer, dry it naturally, immerse it in 6M sodium hydroxide solution, and finally rinse it with deionized water.

[0049] S4, applying the conductive layer solution on the support layer by a doctor blade method, and performing a chemical treatment after in-situ crosslinking, wherein the chemical treatment comprises immersing the conductive layer in a 6M sodium hydroxide solution for 15 minutes, and then washing it with deionized water;

[0050] S5. Use nanosecond laser technology to perform anti-deformation structural treatment on the surfaces of the conductive layer and the support layer to form a skin electrode with patterned textures.

[0051] The specific implementation steps of the present invention are as follows:

[0052] Preparation of MXene powder:

[0053] Dissolve 2 g of lithium fluoride (LiF) in 40 mL of hydrochloric acid (HCl) solution and stir well.

[0054] 2 g of titanium aluminum carbide (Ti3AlC2) powder was gradually added, and stirring and centrifugal washing were continued until the pH value of the supernatant was greater than 6.

[0055] After ice bath ultrasonic treatment for 45 minutes, the product was centrifuged again and freeze-dried for 24 hours to obtain a single-layer MXene powder.

[0056] Preparation of support layer:

[0057] Take 50 g of 0.3 wt% bacterial cellulose solution, add 0.45 g of tannic acid, and adjust the pH value to 8 with 1 M Tris solution.

[0058] After stirring for 24 hours, the mixture was filtered and dried to form a film of bacterial cellulose and tannic acid.

[0059] Preparation of conductive layer solution:

[0060] Take 500 mg of the MXene powder prepared above, disperse it in 2-5 g of deionized water, and stir until it is completely dissolved.

[0061] Add 20 mL of pre-prepared polyvinyl alcohol (PVA) solution and continue stirring to form a uniform conductive layer solution.

[0062] Coating and chemical treatment of conductive layer:

[0063] The conductive layer solution is evenly coated on the supporting layer film prepared in step 2 and dried naturally.

[0064] The dried film was immersed in 6M sodium hydroxide solution for 15 minutes and then rinsed with deionized water.

[0065] Patterning of special textures:

[0066] Using nanosecond laser technology, the surfaces of the conductive layer and the supporting layer are precisely cut according to the designed special patterns (such as grid, wavy lines or dot distribution) to form skin electrodes with special patterns.

[0067] The following is an experimental data description of the gel electrode of the present invention:

[0068] like Figure 3 This is the PVA gradient stretching data graph. Figure 4 This is a graph of bacterial cellulose gradient stretching data. The following is an example of a composite test using 100 mg / mL PVA and 0.3 wt% BC. Figure 5 The stress-strain curves of PVA, bacterial cellulose and their composite membranes are shown in the attached figure. Figure 6 By comparing the maximum stress, elastic modulus and toughness of the three films, it can be concluded that the composite film has strong anti-deformation ability.

[0069] like Figure 7 As shown in the figure, by comparing with the commercial electrode signal monitoring data, it can be seen that the prepared composite film can still maintain good signal stability under various bending conditions. Figure 8 The noise and signal-to-noise ratio comparison chart with commercial electrodes shows that the prepared composite film can provide clearer and more stable signal output, greatly improving the quality and efficiency of electrophysiological signal monitoring.

[0070] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0071] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

[0072] The present invention and its embodiments are described above, and such description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design a structure and embodiment similar to the technical solution without creativity, which should belong to the protection scope of the present invention.

Claims

1. A biocompatible gel electrode capable of suppressing deformation signal crosstalk, characterized in that: The skin electrode includes a conductive layer composed of high-crystallinity polyvinyl alcohol (PVA) and MXene, and a supporting layer formed by a composite of bacterial cellulose and tannic acid located below the conductive layer. The surfaces of the conductive layer and the supporting layer have patterned textures cut by nanosecond laser technology, and the patterned textures are used to reduce motion artifacts.

2. The method for preparing a biocompatible gel electrode capable of suppressing deformation signal crosstalk according to claim 1, characterized in that: The following steps are involved: S1. preparing MXene powder; S2, preparing a composite support layer of bacterial cellulose and tannic acid; S3, mixing MXene powder with PVA solution to form a conductive layer solution; S4, applying the conductive layer solution on the support layer by a doctor blade method, and performing chemical treatment after in-situ cross-linking; S5. Use nanosecond laser technology to perform anti-deformation structural treatment on the surfaces of the conductive layer and the support layer to form a skin electrode with patterned textures.

3. The method for preparing a biocompatible gel electrode capable of suppressing deformation signal crosstalk according to claim 2, characterized in that: The MXene is prepared by the following steps: a1. Dissolve lithium fluoride LiF in hydrochloric acid HCl solution and stir evenly; a2. Add aluminum carbide Ti3AlC2 powder gradually into the above mixed solution, stir for 24 hours and centrifuge and wash until the pH value of the supernatant is greater than 6; a3. After ice bath ultrasonic treatment and re-centrifugation, the product is freeze-dried to obtain a single-layer MXene powder. The re-centrifugation speed is preferably 3500 r min -1 .

4. The method for preparing a biocompatible gel electrode capable of suppressing deformation signal crosstalk according to claim 2, characterized in that: The support layer is prepared by the following steps: b1. Add tannic acid to the bacterial cellulose solution and adjust the pH to 8 using the prepared 1M tris solution. Stir for 24 hours and then filter and dry to form a film.

5. The method for preparing a biocompatible gel electrode capable of suppressing deformation signal crosstalk according to claim 2, characterized in that: The conductive layer is prepared by the following steps: c1. Disperse MXene powder in deionized water, add it to the PVA solution, and stir evenly to form a mixed solution. The preferred amount of the MXene powder is 0.5 g, and the preferred amount of the PVA solution is 20 mL; c2. Apply the mixed solution on the support layer, dry it naturally, immerse it in 6M sodium hydroxide solution, and finally rinse it with deionized water.

6. A method for preparing a biocompatible gel electrode capable of suppressing deformation signal crosstalk, a skin electrode with biocompatibility and low motion artifacts according to claim 2, characterized in that: The patterned design specifically includes grid, wavy lines and dot matrix distribution, and its purpose is to use the patterned texture to resist greater deformation, so as to reduce motion artifacts and reduce signal interference caused by motion.

7. The method for preparing a biocompatible gel electrode capable of suppressing deformation signal crosstalk according to claim 2, characterized in that: The chemical treatment includes soaking the conductive layer in 6M sodium hydroxide solution for 15 minutes and then rinsing it with deionized water.

Images