Biomimetic hydrophobic wet-sticky flexible electrode for urodynamic monitoring and method of making

Abstract

The application discloses a bionic hydrophobic wet adhesion flexible electrode for urodynamic monitoring and a preparation method thereof. The bionic hydrophobic wet adhesion flexible electrode comprises a bionic super-hydrophobic outer layer, a stretchable conductive layer and a hydrogel adhesive layer. The bionic super-hydrophobic outer layer is arranged on the hydrogel adhesive layer, and the stretchable conductive layer is arranged between the bionic super-hydrophobic outer layer and the hydrogel adhesive layer. The bionic hydrophobic wet adhesion flexible electrode can effectively ensure the conformal adhesion of the electrode and human skin, significantly improve the anti-motion artifact performance, isolate the external water stain interference and resist the influence of urine, and will not fall off when the urine seeps and stagnates, so that the urodynamic monitoring can be effectively realized, and the abnormal urination symptoms can be assisted to be monitored.

Description

TECHNICAL FIELD

[0001] The present application relates to a biomimetic hydrophobic wet-adhesion flexible electrode for urodynamic monitoring and a preparation method thereof. BACKGROUND

[0002] The excitation of sympathetic nerves can make the bladder wall relax and the internal sphincter contract, thereby preventing the discharge of urine. Damage to the sympathetic nerves of the human urinary system can cause difficulty or uncontrollable urination. In addition, lower urinary tract obstruction and detrusor dyssynergia can also cause urinary incontinence. The history of urinary incontinence is complex, and the type of urinary incontinence needs to be determined according to symptoms, pelvic ultrasound examination and urodynamic examination to develop a treatment plan. However, traditional rigid electrodes are difficult to collect high-quality electromyographic signals during movement, and may cause skin irritation during long-term measurement, which cannot meet the current needs of medical technology.

[0003] In recent years, the rapid development of flexible electronic technology has solved the above problems to some extent. Flexible electrode sensors can be bent and stretched to some extent, are very thin, can achieve conformal attachment to the skin, and will not produce large relative displacement with the movement of the human body and skin deformation, thereby reducing the corresponding signal interference. Hydrogels have good stretching ability and are commonly used in skin electrodes, but the stretching ability and wet adhesion ability of the commonly used flexible electrodes are not enough, and cannot solve the problems of high strain and easy detachment in urodynamic monitoring.

[0004] In urodynamic monitoring, the skin will deform greatly due to the movement of the patient's limbs. The wet adhesion and hydrophobicity of the electrodes used in hospitals are poor, so the electrodes are often washed off by urine or physiological saline, resulting in detachment or loss of conductivity. Therefore, it is of great significance to develop a flexible electrode with wet adhesion and hydrophobicity for monitoring abnormal urination symptoms, judging patient conditions and assisting treatment. SUMMARY

[0005] The technical problem to be solved by the present application is to provide a biomimetic hydrophobic wet-adhesion flexible electrode for urodynamic monitoring and a preparation method thereof, which can effectively ensure the conformal attachment of the electrode to the human skin, significantly improve the anti-motion artifact performance, and at the same time, isolate external water stains and resist the influence of urine, and will not fall off when urine seeps and stagnates, effectively realizing urodynamic monitoring and assisting in monitoring abnormal urination symptoms.

[0006] The technical solution adopted by the present application to solve the above technical problems is:

[0007] A bionic hydrophobic wet adhesive flexible electrode for urodynamic monitoring, comprising a bionic super-hydrophobic outer layer, a stretchable conductive layer and a hydrogel adhesive layer, the bionic super-hydrophobic outer layer is arranged on the hydrogel adhesive layer, and the stretchable conductive layer is arranged between the bionic super-hydrophobic outer layer and the hydrogel adhesive layer.

[0008] According to the above technical scheme, the hydrogel adhesive layer comprises a wet adhesive hydrogel electrode and a hydrophobic hydrogel outer layer arranged in sequence.

[0009] According to the above technical scheme, the wet adhesive hydrogel electrode comprises CHI-GA monomers, 2-(2-phenoxyethoxy) ethyl acrylate (PDEA) monomers, quaternary ammonium salt (QDM) cation monomers, a-ketoglutaric acid, N,N'-methylene bisacrylamide (MBAA), and the above components are mixed with DMSO solvent, ultrasonically shaken for a period of time T, degassed, and cured under ultraviolet light to obtain the adhesive layer, and then soaked in deionized water to replace the DMSO solvent.

[0010] According to the above technical scheme, the hydrophobic hydrogel outer layer is prepared by pouring the hydrogel prepolymer solution into a bionic lotus leaf negative mold and curing under ultraviolet light, and then soaking in deionized water to replace the DMSO solvent, thereby obtaining the hydrophobic hydrogel outer layer.

[0011] According to the above technical scheme, the stretchable conductive layer is formed by curing a conductive paste, and the myoelectric signals generated during urination are collected through the ion channels at the interface of the hydrogel adhesive layer. The bionic hydrophobic layer combines the bionic lotus leaf microstructure surface and the hydrophobic groups in the hydrogel, which can prevent external water stains from interfering with the electrode, hydrogel swelling, and interface detachment.

[0012] The biomimetic hydrophobic wet-adhesion flexible electrode not only can collect high-quality electrical signals when the skin is deformed, but also can resist the influence of urine seepage and immersion, and is suitable for urodynamic monitoring. The hydrogel adhesion layer realizes wet adhesion by combining covalent bond, electrostatic bond and hydrophobic interaction; the biomimetic super-hydrophobic outer layer realizes excellent hydrophobic performance by combining hydrophobic benzene ring molecular chain and biomimetic lotus leaf microstructure. Wet adhesion is realized based on covalent coupling of pyrogallol groups to chitosan succinimide; and the hydrophobicity of the interface is improved by the synergistic effect of the biomimetic super-hydrophobic lotus leaf microstructure and the benzene ring hydrophobic group in the 2-(2-phenoxyethoxy)ethyl acrylate (PDEA) monomer. The wet adhesion principle based on covalent coupling of pyrogallol groups to chitosan succinimide is as follows: the PDEA hydrophobic π bond breaks the hydration layer, the CHI-GA and QDM molecular chains increase the number of quaternary ammonium salt cation monomers under the action of acid, the electrostatic coupling effect between the skin interface is strengthened, and the Schiff base Michael addition reaction occurs between the GA pyrogallol group and the interface, realizing tight adhesion.

[0013] The synthesis of the biomimetic super-hydrophobic outer layer includes the following steps:

[0014] In step a, CHI-GA monomer, 2-(2-phenoxyethoxy)ethyl acrylate (PDEA) monomer, quaternary ammonium salt (QDM) cation monomer, a-ketoglutaric acid and N,N'-methylene bisacrylamide (MBAA) are sequentially added to 10 ml of DMSO solvent, ultrasonically oscillated for 30 min to obtain a uniform mixed hydrogel pre-polymer solution, the hydrogel pre-polymer solution is added to a lotus leaf microstructure negative film, and photopolymerization is performed for 1 hour;

[0015] In step b, after polymerization is completed, the product is immersed in deionized water, and a dilute hydrochloric acid solution is added dropwise to make the pH acidic;

[0016] In step c, the product is soaked for 24 hours to reach equilibrium, and a biomimetic super-hydrophobic outer layer with a biomimetic lotus leaf structure is obtained.

[0017] A preparation method of a biomimetic hydrophobic wet-adhesion flexible electrode for urodynamic monitoring is provided, which includes the following steps:

[0018] In step 1, a PDMS pre-polymer solution is spin-coated on a glass substrate, and the substrate is placed in an oven for solidification to obtain a PDMS base layer;

[0019] In step 2, a laser is used to engrave a patterned PVC electrode mask, the mask is attached to the PDMS base layer, and conductive paste is scraped onto the electrode mask, which is then placed in an oven for solidification to form a conductive paste electrode layer;

[0020] In step 3, the conductive paste electrode layer is laser-engraved to form a patterned flexible substrate;

[0021] Step 4, immerse the above electrode in a benzophenone solution for soaking;

[0022] Step 5, after soaking is completed, place the above electrode into a PMMA mold with the electrode layer facing up, pour the hydrogel prepolymer solution to form a pre-crosslinked hydrogel layer;

[0023] Step 6, irradiate the above pre-crosslinked hydrogel layer with ultraviolet light, and obtain a hydrogel adhesive interface layer after crosslinking is completed;

[0024] Step 7, treat the back of the above hydrogel electrode with a benzophenone solution;

[0025] Step 8, after treatment is completed, pour the hydrogel prepolymer solution, cover the PDMS negative mold containing the lotus microstructure, and perform photopolymerization;

[0026] Step 9, immerse the above electrode in deionized water to obtain a final biomimetic hydrophobic wet-adhesive flexible electrode.

[0027] According to the technical scheme, in the step 5, the preparation method of the hydrogel prepolymer solution comprises the following steps: uniformly mixing CHI-GA monomers, 2-(2-phenoxyethoxy)ethyl acrylate (PDEA) monomers, quaternary ammonium salt (QDM) cationic monomers, a-ketoglutaric acid and N,N'-methylene bisacrylamide (MBAA) in a DMSO solution to obtain a hydrogel prepolymer solution.

[0028] According to the technical scheme, the CHI-GA monomer refers to a chitosan succinimide covalently coupled pyrogallol group.

[0029] According to the technical scheme, the preparation method of the CHI-GA monomer comprises the following steps:

[0030] Step 5.1, degas 5mmol-15mmol CHI into a MES solution with a pH of 5.0-6.0; (in this embodiment, the optimal pH of the MES solution is 5.4)

[0031] Step 5.2, after the above solution is degassed, 3mmol-5mmol EDC and 3mmol-5mmol NHS are added and mixed with magnetic stirring and degassing;

[0032] Step 5.3, after the above solution is degassed, 3mmol-5mmol GA gallic acid is added and sealed for stirring;

[0033] Step 5.4, after the above solution is stirred, dialysis is performed for 48 hours, and freeze-drying is performed to obtain CHI-GA monomers.

[0034] According to the technical scheme, in the step 8, the preparation method of the lotus leaf microstructure mold comprises the following steps: pouring the uncured PDMS on fresh lotus leaves, and then placing the lotus leaves on a heating table to solidify the uncured PDMS; after solidification, uniformly spraying a release agent on the surface of the uncured PDMS, and drying to obtain the PDMS negative mold containing the lotus leaf microstructure.

[0035] The present application has the following advantages:

[0036] The flexible electrode can effectively ensure the conformal attachment of the electrode to the human skin, significantly improve the motion artifact resistance, isolate the external water stain interference and resist the influence of urine, overcome the defect that the traditional hydrophilic hydrogel is invalid due to water absorption and swelling, and still be able to collect high-quality physiological signals without falling off when urine seeps and stagnates, thereby effectively realizing the urodynamic monitoring and having broad prospects in the aspects of auxiliary monitoring of urination abnormal symptoms and quantitative evaluation of patient conditions. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 is an exploded schematic view of the bionic hydrophobic wet-adhesion flexible electrode for urodynamic monitoring in the embodiment of the present application;

[0038] Figure 2 is a network structure diagram of the hydrogel adhesion layer in the embodiment of the present application;

[0039] Figure 3 is a preparation process diagram of the bionic hydrophobic wet-adhesion flexible electrode for urodynamic monitoring in the embodiment of the present application;

[0040] Figure 4 is a front view of the super-hydrophobic outer layer with a bionic lotus leaf structure in the embodiment of the present application;

[0041] Figure 5 is a perspective view of the super-hydrophobic outer layer with a bionic lotus leaf structure in the embodiment of the present application;

[0042] Figure 6 is a working schematic view of the bionic hydrophobic wet-adhesion flexible electrode for urodynamic monitoring in the embodiment of the present application;

[0043] In the figure, 1 is a hydrogel prepolymer, 2 is a PDMS base layer, 3 is a PVC electrode mask, 4 is a conductive paste electrode layer, 5 is a PMMA mold, 6 is a viscous hydrogel, 7 is a bionic hydrophobic outer layer, 8 is a stretchable conductive layer, 9 is a hydrogel adhesion layer, 10 is skin, 11 is a benzophenone solution, 12 is a PDMS negative mold, 13 is deionized water, and 14 is a bionic hydrophobic wet-adhesion flexible electrode. DETAILED DESCRIPTION

[0044] The present application will be described in detail below in combination with the drawings and embodiments.

[0045] Referring to Figures 1-2 As shown in FIG. 1, the present application provides a biomimetic hydrophobic wet adhesive flexible electrode for urodynamic monitoring in embodiment 1, characterized in that it comprises a biomimetic super-hydrophobic outer layer, a stretchable conductive layer and a hydrogel adhesive layer, the biomimetic super-hydrophobic outer layer is arranged on the hydrogel adhesive layer, and the stretchable conductive layer is arranged between the biomimetic super-hydrophobic outer layer and the hydrogel adhesive layer.

[0046] Further, the hydrogel adhesive layer comprises a wet adhesive hydrogel electrode and a hydrophobic hydrogel outer layer arranged in sequence, the wet adhesive hydrogel electrode directly contacts the skin, and the stretchable conductive layer is arranged between the wet adhesive hydrogel electrode and the hydrophobic hydrogel outer layer; the hydrogel adhesive layer serves as an adhesive layer to form a hydrogel wet adhesive flexible interface, which can promote the entire electrode to maintain conformal contact with the human skin and has the ability to resist motion artifacts.

[0047] Further, the wet adhesive hydrogel flexible electrode comprises CHI-GA monomers, 2-(2-phenoxyethoxy)ethyl acrylate (PDEA) monomers, quaternary ammonium salt (QDM) cationic monomers, a-ketoglutaric acid, N,N'-methylene bisacrylamide (MBAA), and the above components are mixed with DMSO solvent, ultrasonically shaken for a period of time T=30 min to obtain a hydrogel pre-polymer solution, degassed and cured under ultraviolet light for 1 h to obtain the adhesive layer, and soaked in deionized water for 24 h to replace the DMSO solvent.

[0048] Further, the hydrophobic hydrogel outer layer is prepared by pouring the hydrogel pre-polymer solution into a biomimetic lotus leaf negative mold and curing under ultraviolet light for 1 h, and soaking in deionized water for 24 h to replace the DMSO solvent, i.e. the hydrophobic hydrogel outer layer is obtained.

[0049] Further, the stretchable conductive layer realizes the collection of myoelectric signals generated during urination through the ion channels at the interface of the hydrogel adhesive layer, and the biomimetic hydrophobic layer combines the lotus leaf microstructure surface and the hydrophobic groups in the hydrogel, which can prevent external water stains from interfering with the electrode, hydrogel water absorption and swelling, interface detachment and other problems (ions existing in the hydrogel adhesive layer form ion channels, which constitute a conductive path when the electrode collects electrophysiological signals, promoting signal transmission).

[0050] Further, the stretchable conductive layer is in the shape of a snake, forming a snake-shaped electrode layer.

[0051] The biomimetic hydrophobic wet-adhesive flexible electrode not only can collect high-quality electrical signals when the skin is deformed, but also can resist the influence of urine seepage and immersion, and is suitable for urodynamic monitoring. The hydrogel adhesive layer realizes wet adhesion by combining covalent bond, electrostatic bond and hydrophobic interaction; the biomimetic super-hydrophobic outer layer realizes excellent hydrophobic performance by combining hydrophobic benzene ring molecular chain and biomimetic lotus leaf microstructure. Wet adhesion is realized based on covalent coupling of catechol groups to chitosan succinimide; and the hydrophobicity of the interface is improved by the synergistic effect of the biomimetic super-hydrophobic lotus leaf microstructure and the benzene ring hydrophobic group in the 2-(2-phenoxyethoxy) ethyl acrylate (PDEA) monomer. The wet adhesion principle based on covalent coupling of catechol groups to chitosan succinimide is as follows: the PDEA hydrophobic π bond breaks the hydration layer, the CHI-GA and QDM molecular chains increase the number of quaternary ammonium salt cation monomers under the action of acid, and the electrostatic coupling effect between the skin interface is strengthened, and at the same time, the GA catechol group and the interface occur Schiff base Michael addition reaction to realize tight adhesion.

[0052] The synthesis of the biomimetic super-hydrophobic outer layer includes the following steps:

[0053] In step a, CHI-GA monomer, 2-(2-phenoxyethoxy) ethyl acrylate (PDEA) monomer, quaternary ammonium salt (QDM) cationic monomer, a-ketoglutaric acid, and MBAA are sequentially added to 10 ml of DMSO solvent, and ultrasonic oscillation is performed for 30 min to obtain a uniform mixed hydrogel pre-polymer solution, wherein the mass fraction of CHI-GA monomer, 2-(2-phenoxyethoxy) ethyl acrylate (PDEA) monomer, quaternary ammonium salt (QDM) cationic monomer, a-ketoglutaric acid, and MBAA in the total mass of the hydrogel pre-polymer solution is 5-15 wt%, 2-5 wt%, 5-10 wt%, 0.1 wt%, and 0.02 wt%, respectively. The above hydrogel pre-polymer solution is added to a negative film with lotus leaf microstructure, and photopolymerization is performed for 1 hour.

[0054] In step b, after polymerization is completed, the product is immersed in deionized water, and a dilute hydrochloric acid solution is added dropwise to make the pH acidic.

[0055] In step c, the product is soaked for 24 hours, and a biomimetic lotus leaf structure biomimetic super-hydrophobic outer layer is obtained after reaching equilibrium.

[0056] A preparation method of a biomimetic hydrophobic wet-adhesive flexible electrode for urodynamic monitoring is provided, and the preparation method includes the following steps:

[0057] In step 1, a PDMS pre-polymer solution is spin-coated on a glass substrate, and the glass substrate is placed in an oven for 90-degree curing for half an hour to obtain a PDMS base layer.

[0058] Step 2, laser engraving patterned PVC electrode mask, paste the mask on the PDMS base layer, and coat the conductive paste on the electrode mask, put it into the oven, cure at 120 degrees for 1 hour, form the conductive paste electrode layer;

[0059] Step 3, laser engraving patterned flexible substrate for the above conductive paste electrode layer;

[0060] Step 4, immerse the above electrode in a 10% benzophenone (benzophenone: ethanol = 1:9) solution for 10 minutes;

[0061] Step 5, after soaking, put the above electrode into a PMMA mold, with the electrode layer facing up, pour the hydrogel prepolymer solution to form a pre-crosslinked hydrogel layer;

[0062] Step 6, irradiate the above pre-crosslinked hydrogel layer with 365 nm ultraviolet light for 30 min, and obtain the hydrogel adhesive interface layer after crosslinking is completed;

[0063] Step 7, treat the back of the above hydrogel electrode with a benzophenone solution;

[0064] Step 8, after treatment, pour the hydrogel prepolymer solution, cover the PDMS negative mold containing the lotus microstructure, and perform photopolymerization;

[0065] Step 9, immerse the above electrode in deionized water for 24 hours, and replace DMSO to obtain the final biomimetic hydrophobic wet adhesive flexible electrode.

[0066] Further, in the steps 5 and 8, the preparation method of the hydrogel prepolymer solution comprises the following steps: adding CHI-GA monomer, 2-(2-phenoxyethoxy) ethyl acrylate (PDEA) monomer, quaternary ammonium salt (QDM) cationic monomer, a-ketoglutaric acid, and MBAA into 10 ml of DMSO solvent in sequence, ultrasonic oscillation for 30 min, and uniformly mixing in the DMSO solution to obtain the hydrogel prepolymer solution, wherein the mass fraction of CHI-GA monomer, 2-(2-phenoxyethoxy) ethyl acrylate (PDEA) monomer, quaternary ammonium salt (QDM) cationic monomer, a-ketoglutaric acid, and MBAA is 5-15wt%, 2-5wt%, 5-10wt%, 0.1wt%, and 0.02wt% of the total mass of the hydrogel prepolymer solution, respectively.

[0067] Further, the CHI-GA monomer refers to a chitosan succinimide covalently coupled o-benzotriazolyl group; PDMS is polydimethylsiloxane; Figure 1 DMSO is dimethyl sulfoxide; PMMA is polymethyl methacrylate

[0068] Further, the preparation method of the CHI-GA monomer comprises the following steps:

[0069] Step 5.1, 5mmol-15mmol chitosan (CHI) was added into the morpholine ethanesulfonic acid (MES) solution with pH 5.0-6.0 and degassed for half an hour; (the optimal pH of the MES solution in this embodiment is 5.4)

[0070] Step 5.2, after the above solution was degassed, 3mmol-5mmol 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) and 3mmol-5mmol n-hydroxysuccinimide (NHS) were added and mixed and magnetically stirred for half an hour, and degassed for 15 minutes;

[0071] Step 5.3, after the above solution was degassed, 3mmol-5mmol GA gallic acid was added and sealed and stirred for 6 hours;

[0072] Step 5.4, after the above solution was stirred, it was dialyzed for 48 hours and freeze-dried to obtain CHI-GA monomer.

[0073] Further, in the step 8, the preparation method of the lotus leaf microstructure mold comprises the following steps: pouring the uncured PDMS on a fresh lotus leaf, then placing it on a 90-degree heating table to make it solidify for one hour; after solidification, evenly spraying a release agent on the surface, and drying to obtain a PDMS negative mold containing lotus leaf microstructure.

[0074] The working principle of the present application is: 1. The bionic hydrophobic wet adhesive flexible electrode provided by the present application is a skin-attached hydrogel electrode, which has good tensile deformation ability on the basis of realizing high-quality collection of electrical signals. The flexible electrode has excellent wearability, and at the same time realizes continuous monitoring of the urodynamic electrical signals of patients during urination, assisting in judging the condition of patients. The flexible skin electrode can make patients free from the discomfort during the wearing process of rigid electrodes, and at the same time avoid the trouble caused to patients during the frequent replacement of electrodes, further improving the wearing comfort of the flexible device. 2. The bionic hydrophobic wet adhesive flexible electrode combines the synergistic effect of lotus leaf surface microstructure and PDEA hydrophobic π bond, which can significantly improve the hydrophobicity of the hydrogel interface layer, avoid the performance degradation or electrical leakage of the electrode under external urine immersion and flushing, and ensure the stable work of the electrode in a humid environment, so that it is suitable for urodynamic detection process. 3. The bionic hydrophobic wet adhesive flexible electrode has good wet adhesion. The chemical adhesion of the coating is improved by combining the Schiff base and Michael addition reaction of the catechol group, and the adhesion is enhanced by the electrostatic coupling effect of the cationic monomer and the amino and carboxyl groups of the skin, which can prevent the electrode from falling off due to the flushing of external liquid, help to reduce the interference of external factors, improve the measurement accuracy and the stability of the electrode, and prolong the service life of the electrode in a humid environment. 4. The preparation process of the bionic hydrophobic wet adhesive flexible electrode is simple and efficient, which simplifies the complexity of the preparation process and reduces the manufacturing cost, and can realize large-area preparation and batch processing.

[0075] Example 2

[0076] Referring to Figure 3 and ​ , the present application provides a bionic hydrophobic wet adhesive flexible electrode manufacturing process diagram, and the preparation process of the hydrophobic wet adhesive flexible electrode is described below in conjunction with examples.

[0077] 1) Put CHI into the MES solution, mix and degas. Preferably, the amount of substance of CHI is 5-15 mmol, the pH value of the MES solution is 5.4, and the degassing time is half an hour.

[0078] 2) Add EDC and NHS to the above degassed solution, mix with magnetic stirring and then degas. Preferably, the amount of substance of EDC and NHS is 3 mmol each, the magnetic stirring time is half an hour, and the degassing time is 15 minutes.

[0079] 3) Add GA gallic acid to the above degassed solution, seal and stir. Preferably, the amount of substance of GA gallic acid is 3 mmol, and the sealed stirring time is 6 hours.

[0080] 4) The solution after the stirring is completed is dialyzed, and CHI-GA monomers are obtained by freeze-drying after dialysis. Preferably, the dialysis time is 48 hours.

[0081] 5) The uncured polydimethylsiloxane is cast on a fresh lotus leaf, and then placed on a heating table to cure, preferably, the heating temperature is 90 degrees, and the heating time is 1 hour.

[0082] 6) The mold obtained after curing is uniformly sprayed with a release agent, and a lotus leaf microstructure mold is obtained after drying.

[0083] The CHI-GA monomers obtained in step (4) are mixed with 2-(2-phenoxyethoxy)ethyl acrylate (PDEA) monomers, quaternary ammonium salt (QDM) cationic monomers, a-ketoglutaric acid, and MBAA in a DMSO solution to obtain a hydrogel prepolymer 1. Preferably, the mass percentage of CHI-GA monomers, PDEA monomers, QDM cationic monomers, a-ketoglutaric acid, and MBAA is 5-15wt%, 2-5wt%, 5-10wt%, 0.1wt%, and 0.02wt%, respectively.

[0084] The above is only a preferred embodiment of the present application, of course, cannot limit the scope of the patent rights of the present application, therefore, equivalent changes made in the scope of the patent application of the present application, still belongs to the protection scope of the present application.

Claims

1. A biomimetic hydrophobic wet-sticky flexible electrode for urodynamic monitoring, characterized in that, The biomimetic super-hydrophobic outer layer, the stretchable conductive layer and the hydrogel adhesive layer are arranged in sequence. The hydrogel adhesive layer comprises a wet-adhesion hydrogel electrode and a hydrophobic hydrogel outer layer arranged in sequence. The wet-adhesion hydrogel electrode comprises CHI-GA monomers, 2-(2-phenoxyethoxy)ethyl acrylate monomers and quaternary ammonium salt cation monomers. The CHI-GA monomers refer to chitosan succinimide covalently coupled pyrogallol groups. The preparation method of the CHI-GA monomers comprises the following steps: The chitosan CHI is added into a morpholine ethanesulfonic acid (MES) solution for degassing; After the degassing of the solution is completed, EDC and NHS are added for mixing, stirring and degassing, and then GA gallate is added for sealing and stirring; After the stirring of the solution is completed, the CHI-GA monomers are obtained through dialysis and freeze-drying.

2. The bionic hydrophobic wet-sticky flexible electrode for urodynamic monitoring according to claim 1, characterized in that, The components of the CHI-GA monomers, the 2-(2-phenoxyethoxy)ethyl acrylate monomers, the quaternary ammonium salt cation monomers, the a-ketoglutaric acid and the N,N'-methylene bisacrylamide in the wet-adhesion hydrogel electrode are mixed with DMSO solvent, and then ultrasonic oscillation is performed for a period of time T to obtain a hydrogel pre-polymer solution, which is degassed and cured under ultraviolet light to obtain the adhesive layer, and then the adhesive layer is soaked in deionized water to replace the DMSO solvent.

3. The bionic hydrophobic wet-sticky flexible electrode for urodynamic monitoring according to claim 1, characterized in that, The hydrophobic hydrogel outer layer is prepared by pouring a hydrogel pre-polymer solution into a biomimetic lotus leaf negative mold and curing under ultraviolet light, and then the hydrophobic hydrogel outer layer is obtained by soaking in deionized water to replace the DMSO solvent.

4. The bionic hydrophobic wet-sticky flexible electrode for urodynamic monitoring according to claim 1, characterized in that, The stretchable conductive layer is formed by curing a conductive paste, and the myoelectric signals generated in the urination process are collected through the ion channels of the hydrogel adhesive layer.

5. The bionic hydrophobic wet-sticky flexible electrode for urodynamic monitoring according to claim 1, wherein, The synthesis of the biomimetic super-hydrophobic outer layer comprises the following steps: In step a, the CHI-GA monomers, the 2-(2-phenoxyethoxy)ethyl acrylate monomers, the quaternary ammonium salt cation monomers, the a-ketoglutaric acid and the N,N'-methylene bisacrylamide are sequentially added into a DMSO solvent, and then ultrasonic oscillation is performed to obtain a uniformly mixed hydrogel pre-polymer solution, which is added into a lotus leaf microstructure negative film for photo-induced polymerization. In step b, after the polymerization is completed, the biomimetic super-hydrophobic outer layer is obtained by immersing in deionized water and adding a dilute hydrochloric acid solution to make the PH acidic. In step c, the biomimetic super-hydrophobic outer layer with a biomimetic lotus leaf structure is obtained by soaking to reach equilibrium.

6. A method of making the biomimetic hydrophobic wet-sticky flexible electrode for urodynamic monitoring of claim 1, characterized by, The method comprises the following steps: In step 1, a PDMS pre-polymer solution is spin-coated on a glass substrate, and then the glass substrate is placed in an oven for curing to obtain a PDMS base layer. In step 2, a laser is used to engrave a patterned PVC electrode mask, the mask is attached to the PDMS base layer, and a conductive paste is scraped onto the electrode mask, which is then placed in an oven for curing to form a conductive paste electrode layer. In step 3, the conductive paste electrode layer is laser-engraved to pattern a flexible substrate. In step 4, the conductive paste electrode layer is immersed in a benzophenone solution for soaking. Step 5, after soaking is completed, the conductive paste electrode layer is placed in a PMMA mold, the electrode layer faces up, the hydrogel prepolymer solution is poured to form a pre-crosslinked hydrogel layer; Step 6, the pre-crosslinked hydrogel layer is irradiated with ultraviolet light, and a hydrogel adhesive interface layer is obtained after crosslinking is completed; Step 7, the back of the hydrogel adhesive interface layer is treated with a benzophenone solution; Step 8, after the treatment is completed, the hydrogel prepolymer solution is poured, the PDMS negative mold containing the lotus microstructure is covered, photopolymerization is performed, and a flexible electrode is formed; Step 9, the flexible electrode is immersed in deionized water to obtain a final biomimetic hydrophobic wet-adhesive flexible electrode.

7. The production method according to claim 6, wherein In steps 5 and 8, the preparation method of the hydrogel prepolymer solution comprises the following steps: uniformly mixing CHI-GA monomers, 2-(2-phenoxyethoxy) ethyl acrylate monomers, quaternary ammonium salt cation monomers, a-ketoglutaric acid and N,N'-methylene bisacrylamide in a DMSO solution to obtain a hydrogel prepolymer solution.

8. The preparation method according to claim 7, characterized in that, The preparation method of the CHI-GA monomer comprises the following steps: Step 5.1, 5mmol-15mmol CHI is added to a MES solution with a pH of 5.0-6.0 and degassed; Step 5.2, after the solution is degassed, 3mmol-5mmol EDC and 3mmol-5mmol NHS are added and mixed with magnetic stirring and degassing; Step 5.3, after the solution is degassed, 3mmol-5mmol GA gallic acid is added and stirred under seal; Step 5.4, after the solution is stirred, dialysis is performed for 48 hours, and freeze-drying is performed to obtain CHI-GA monomers.

9. The preparation method according to claim 7, characterized in that, In step 8, the preparation method of the lotus microstructure mold comprises the following steps: pouring uncured PDMS on a fresh lotus leaf, then placing the PDMS poured on the fresh lotus leaf on a heating table to cure the PDMS; after curing is completed, a release agent is uniformly sprayed on the surface of the PDMS, and a PDMS negative mold containing a lotus microstructure is obtained after drying.

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