Wireless and battery-free iontophoresis patch for skin care

Abstract

According to the wireless and battery-free electroosmosis patch for skin care, sound energy is converted into electric energy through a sound wave patch, and the electric energy is output to a medicine carrying patch below the sound wave patch, so that ion medicine in the medicine carrying patch permeates into the deep layer of skin through the electroosmosis effect, and the skin care effect is achieved. The ion electroosmosis patch is small in size and high in integration level, medicine permeation can be effectively achieved, the ion electroosmosis patch can be attached to non-woven fabric with medicine, separation of the medicine carrying patch and the sound wave patch is achieved, the ion electroosmosis patch can be reused only by replacing the medicine carrying patch after use, and the problems that an existing ion electroosmosis patch is high in cost, poor in portability, insufficient in wearing comfort and the like are solved.

Description

Technical Field

[0001] The utility model belongs to the field of biomedical engineering devices, and in particular relates to a wireless battery-free iontophoresis patch for skin care. Background Art

[0002] Skin is one of the largest organs in the human body. It is not only a barrier between us and the outside environment, but also the body's first line of defense. Therefore, the demand for skin care has always existed. With the continuous development of medicine and technology, methods for improving skin health and solving specific skin problems are constantly emerging. However, in traditional skin care methods, drugs or active ingredients often face challenges when penetrating the skin. The natural barrier function of the skin limits the effective penetration of many chemicals, resulting in unsatisfactory treatment effects of traditional products. Some common skin problems, such as inflammation, eczema, and signs of aging, often require deeper treatment. In addition, some traditional skin treatment methods may require invasive treatments, such as injections or surgery, which may cause discomfort to patients and increase the risks of treatment. Therefore, there is an urgent need for a skin care method that can not only improve the penetration of drugs into the skin, but also be non-invasive.

[0003] In this context, iontophoresis has attracted considerable attention as a promising innovative skin care option. Iontophoresis involves the use of low-intensity electric current (usually <0.5 mA / cm 2 ) transports charged and neutral substances into the skin based on two main mechanisms of action: electromigration and electroosmosis. Electromigration is based on the principle that like charges repel each other. During electromigration, charged molecules move under the influence of an electric field when in contact with electrodes of the same charge. Thus, when an electric current is applied, cations are repelled by the anode and anions by the cathode and enter the skin. In electroosmosis, a bulk flow of fluid, also called solvent flow, is driven by the potential difference across a charged porous membrane. The electric field causes the free counterions of the charged membrane to migrate towards the oppositely charged electrode, carrying water molecules along the way. This results in a solvent flow that in turn carries neutral and charged molecules in the same direction. The direction of the flow depends on the charge in the biological membrane. In the skin, at physiological pH, it occurs in the direction from the anode to the cathode. This mechanism of action is very useful in the case of neutral and / or larger sized water-soluble molecules, such as peptides and small proteins. Electromigration and electroosmosis occur simultaneously, and their relative strengths determine the net flow direction of the drug molecules.

[0004] Currently, there are analgesia, local sweat induction and other applications for systemic and local skin applications on the market. However, given the dependence of traditional patches on power supplies and a variety of complex electrical components, their portability is significantly limited, and there are also deficiencies in comfort during use. In addition, due to the integration of drugs and the entire iontophoresis patch, the traditional iontophoresis patch needs to be replaced after the drug is consumed, resulting in high cost of use. Summary of the invention

[0005] The utility model provides a wireless battery-free iontophoresis patch for skin care. The designed Helmholtz resonant cavity structure can gather the sound wave energy at the bottom of the resonant cavity. Therefore, the patch uses the piezoelectric principle to convert the mechanical energy in the sound wave into electrical energy. Due to the presence of the resonant cavity, the sound / electric conversion effect of the device is improved, and the wireless battery-free power supply of the patch is realized. The obtained electrical signal is processed by the circuit to obtain a current of appropriate size. The potential difference on the two electrodes forms an electric field, which can guide the diffusion of ionic drugs under the drive of the electric field force, so that the patch can actively operate the drug after the sound wave is activated, thereby realizing the iontophoresis function. In addition, the iontophoresis patch provided by the utility model has the advantages of small size and high integration, and it can be attached to any non-woven fabric with drugs, realizing the separation of the drug-loaded patch and the sound wave patch. After use, only the drug-loaded patch needs to be replaced to be used again, solving the problems of high cost, poor portability, and insufficient wearing comfort of the current iontophoresis patch.

[0006] In order to solve the above technical problems, the specific technical solution of a wireless battery-free iontophoresis patch for skin care of the present invention is as follows:

[0007] Schematic diagram of iontophoresis patch Figure 1 As shown, it consists of two parts: an acoustic wave patch 1 and a drug-loaded patch 2.

[0008] Figure 2 This is a schematic diagram of the composition of the acoustic wave patch: the acoustic wave patch 1 includes a Helmholtz single-hole resonant cavity 1-1, a lead zirconate titanate piezoelectric sheet 1-2, a microcircuit 1-3, and a carbon electrode 1-4.

[0009] The Helmholtz single-hole resonant cavity collects sound waves for the entire device. The resonant cavity is cylindrical in shape, with a circular arc or trapezoidal cross section at the top. A small circular hole is opened in the center of the top of the resonant cavity as the entrance for sound waves. After the sound waves are collected by the Helmholtz single-hole resonant cavity, they vibrate the lead zirconate titanate piezoelectric sheet inside the resonant cavity to provide energy for the entire device.

[0010] Below the Helmholtz single-hole resonant cavity is a lead zirconate titanate piezoelectric sheet, which includes a lead zirconate titanate piezoelectric ceramic, a silver electrode, and a copper substrate. The lower surface of the lead zirconate titanate piezoelectric ceramic is a copper substrate, and the upper surface is a silver electrode, wherein the size of the silver electrode is consistent with that of the lead zirconate titanate piezoelectric ceramic and completely covers the lead zirconate titanate piezoelectric ceramic, and the size of the copper substrate is larger than that of the lead zirconate titanate piezoelectric ceramic;

[0011] There is a microcircuit below the lead zirconate titanate piezoelectric sheet, which converts the current output by the piezoelectric sheet into the current output required for iontophoresis. Two carbon electrodes are connected below the microcircuit, which serve as the positive and negative electrodes of the microcircuit output respectively to accommodate drugs with different electrical properties. An electrical connection is formed between the lead zirconate titanate piezoelectric sheet (1-2), the microcircuit (1-3) and the carbon electrode (1-4).

[0012] Figure 3 The schematic diagram of the composition of the microcircuit is shown. The microcircuit 1-3 includes a polyimide substrate 1-3-1, an upper piezoelectric pad 1-3-2, a lower piezoelectric pad 1-3-3, a rectifier circuit 1-3-4, and a carbon electrode pad 1-3-5. The microcircuit is formed on the polyimide substrate 1-3-1, wherein the polyimide substrate is disc-shaped, and an upper piezoelectric pad is provided at the center of the upper surface of the polyimide substrate 1-3-1, and the size of the upper piezoelectric pad is smaller than that of the polyimide substrate; the lower surface of the polyimide substrate is a carbon electrode pad, a rectifier circuit, and a lower piezoelectric pad. The upper piezoelectric pad is connected to the copper substrate, and the lower piezoelectric pad is connected to the silver electrode of the lead zirconate titanate piezoelectric sheet. The upper piezoelectric pad and the lower piezoelectric pad are connected to the rectifier circuit, so that the current required for ion electroosmosis is output, and the current is output to the drug-loaded patch through the carbon electrodes welded by the two carbon electrode pads.

[0013] Figure 4 The diagram is a composition diagram of a drug-carrying patch, which includes a non-woven fabric 2-1 soaked in a phosphate buffered saline solution and a non-woven fabric 2-2 soaked in an ionic drug solution. When in use, the non-woven fabric soaked in the ionic drug solution is attached to a carbon electrode having the same electrical properties as the ionic drug, and the non-woven fabric soaked in the phosphate buffered saline solution is attached to another electrode.

[0014] The acoustic patch and the drug-loaded patch can be integrated into one. The Helmholtz single-hole resonant cavity is 3D printed from a hard resin material. The piezoelectric patch is composed of lead zirconate titanate piezoelectric ceramic (about 8.5 mm in diameter and about 120 microns in thickness), a copper substrate (about 12 mm in diameter and about 120 microns in thickness), and a silver electrode (the area is the same as that of the piezoelectric ceramic, just covering the top of the piezoelectric ceramic). The polyimide substrate makes the microcircuit bendable and lightweight. The two pads of the piezoelectric patch are located at the top and bottom of the microcircuit, respectively. The top pad is connected to the copper substrate of the lead zirconate titanate piezoelectric patch through a conductive solder paste, and the bottom pad is connected to the silver electrode of the lead zirconate titanate piezoelectric patch with a soft wire. The bottom part of the microcircuit also includes a rectifier circuit and two carbon electrode pads. After the carbon electrode (a disc with a diameter of 10 mm and a thickness of about 1 mm) is connected to the two pads, the contact area between the electrode and the drug-loaded patch is expanded, which is more conducive to the formation of an electric field, thereby promoting drug release. The integrated microcircuit realizes the electrical connection from the piezoelectric patch to the rectifier circuit and then to the carbon electrode, and is encapsulated with polydimethylsiloxane to enhance the durability of the patch.

[0015] When the sound waves are gathered through the resonant cavity, the lead zirconate titanate piezoelectric sheet is subjected to the sound wave pressure, which triggers internal polarization and generates positive and negative opposite charges on its upper and lower surfaces. After the sound waves stop, the ceramic sheet returns to an uncharged state. Based on this piezoelectric effect, the acoustic patch converts the mechanical energy of the sound waves into an AC piezoelectric signal, providing energy for the entire iontophoresis patch. The rectifier circuit processes the piezoelectric signal to obtain a DC signal, forming a potential difference on the two carbon electrodes and an electric field between the carbon electrodes, thereby promoting the release of drugs on the drug-loaded patch.

[0016] The beneficial effects of the present invention are as follows:

[0017] (1) The utility model collects sound wave energy by designing a Helmholtz single-hole resonant cavity structure, converts the sound wave into an electrical signal based on the piezoelectric effect, and then processes it into an electrical signal that enables the drug-loaded electrode to work normally, thereby realizing wireless battery-free power supply for the entire device.

[0018] (2) The embodiments of the utility model can effectively penetrate drugs. When used to treat a psoriasis mouse model, the dexamethasone in the non-woven fabric penetrates into the diseased area of ​​the mouse, successfully treating psoriasis in the mouse.

[0019] (3) The miniaturization and integration of the device and the design of patch and drug separation solve the current problems of iontophoresis patches, such as high cost, poor portability, and insufficient wearing comfort.

[0020] (4) This wireless multiple electroosmotic drug delivery strategy can also be applied to more skin models, such as scleroderma and pressure bedsore models, and is expected to solve a variety of skin diseases. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic diagram of the iontophoresis patch of the present invention;

[0022] Figure 2 It is a schematic diagram of the composition of the acoustic wave patch of the present invention;

[0023] Figure 3 A schematic diagram of the composition of the microcircuit of the present invention;

[0024] Figure 4 It is a schematic diagram of the composition of the drug-carrying patch of the present invention;

[0025] Figure 5 It is a framework diagram of the iontophoresis patch of the present invention. DETAILED DESCRIPTION

[0026] The schematic diagram of the iontophoresis patch in this embodiment is as follows Figure 1 As shown, it consists of two parts: an acoustic wave patch and a drug-loaded patch.

[0027] Figure 2 This is a schematic diagram of the composition of the acoustic patch: including a Helmholtz single-hole resonant cavity 1-1, a lead zirconate titanate piezoelectric sheet 1-2, a microcircuit 1-3, and a carbon electrode 1-4. The Helmholtz single-hole resonant cavity collects sound waves for the entire device. The resonant cavity is cylindrical as a whole, and the top cross-section is arc-shaped or trapezoidal. A small circular hole is opened in the center of the top of the resonant cavity as the entrance of the sound wave. After the sound wave is collected by the Helmholtz single-hole resonant cavity, it vibrates the lead zirconate titanate piezoelectric sheet inside the resonant cavity to provide energy for the entire device.

[0028] The lead zirconate titanate piezoelectric sheet is divided into three parts, the middle part is the lead zirconate titanate piezoelectric ceramic (diameter of about 8.5 mm, thickness of about 120 μm), the lower surface of the lead zirconate titanate piezoelectric ceramic is a copper substrate (diameter of about 12 mm, thickness of about 120 μm), and the upper surface is a silver electrode, wherein the size of the silver electrode is consistent with the lead zirconate titanate piezoelectric ceramic, completely covering the lead zirconate titanate piezoelectric ceramic, and the size of the copper substrate is larger than the lead zirconate titanate piezoelectric ceramic;

[0029] There is a microcircuit underneath the lead zirconate titanate piezoelectric sheet, which converts the current output by the piezoelectric sheet into the current output required for iontophoresis. Two carbon electrodes are connected below the microcircuit, which serve as the positive and negative poles of the microcircuit output to accommodate drugs with different electrical properties.

[0030] The Helmholtz single-hole resonant cavity, piezoelectric sheet, microcircuit, carbon electrode and drug-loaded patch are integrated into one. The single-hole resonant cavity is 3D printed by hard resin material, and the microcircuit is encapsulated by polydimethylsiloxane.

[0031] Figure 3The schematic diagram of the composition of the microcircuit is shown, including a polyimide substrate 1-3-1, an upper piezoelectric pad 1-3-2, a lower piezoelectric pad 1-3-3, a rectifier circuit 1-3-4, and a carbon electrode pad 1-3-5. The microcircuit is formed on the polyimide substrate 1-3-1, wherein the polyimide substrate is disc-shaped, and an upper piezoelectric pad is provided at the center of the upper surface of the polyimide substrate 1-3-1, and the size of the upper piezoelectric pad is smaller than that of the polyimide substrate; the lower surface of the polyimide substrate is a carbon electrode pad, a rectifier circuit, and a lower piezoelectric pad, the upper piezoelectric pad is connected to the copper substrate of the lead zirconate titanate piezoelectric sheet through a conductive solder paste, and the lower piezoelectric pad is connected to the silver electrode of the lead zirconate titanate piezoelectric sheet with a soft wire; the upper piezoelectric pad and the lower piezoelectric pad are connected to the rectifier circuit, so that it outputs the current required for ion electroosmosis, and the current is output to the drug-loaded patch through the carbon electrodes welded by the two carbon electrode pads. The carbon electrode (10 mm diameter disc, about 1 mm thick) is connected to the two pads to expand the contact area between the electrode and the drug-loaded patch, which is more conducive to the formation of an electric field, thereby promoting drug release. An electrical connection is formed between the piezoelectric sheet, the microcircuit, and the carbon electrode.

[0032] Figure 4 2 is a schematic diagram of the composition of the drug-carrying patch, including a non-woven fabric 2-1 soaked in a phosphate buffered saline solution and a non-woven fabric 2-2 soaked in an ionic drug solution. When in use, the non-woven fabric soaked in the ionic drug solution is attached to a carbon electrode with the same electrical properties as the ionic drug, and the non-woven fabric soaked in the phosphate buffered saline solution is attached to another electrode. In this embodiment, since the released drug dexamethasone is electronegative, the non-woven fabric soaked in the dexamethasone solution is placed on the negative electrode, and the non-woven fabric soaked in the phosphate buffered saline solution is placed on the positive electrode to balance the charge.

[0033] When the sound wave passes through the single-hole resonant cavity, the lead zirconate titanate piezoelectric ceramic is subjected to the sound wave pressure in a specific direction, which triggers internal polarization and generates positive and negative opposite charges on its upper and lower surfaces. After the sound wave stops, the piezoelectric piece returns to an uncharged state. Based on this effect, the lead zirconate titanate piezoelectric ceramic piece converts the mechanical energy of the sound wave into electrical energy, providing energy for the entire iontophoresis patch.

[0034] In this embodiment, the patch is powered by playing sound through a mobile phone. The frequency of the audio signal programmed by the mobile phone is 3660 Hz and the sound intensity is 140 decibels. The piezoelectric sheet converts the audio signal into a piezoelectric signal. The frequency of the piezoelectric signal is the same as the frequency of the audio signal. The voltage amplitude of the piezoelectric signal is about 3.2 volts and the current is about 1.2 milliamperes. The rectifier circuit processes the piezoelectric signal to obtain a direct current signal, which forms a potential difference on the two carbon electrodes and an electric field between the carbon electrodes.

[0035] Figure 5The framework diagram of the iontophoresis patch is shown. In this embodiment, sound is transmitted to the piezoelectric patch through a single-hole resonant cavity, and the piezoelectric patch converts the sound signal into an electrical signal, which can be processed by a microcircuit to activate the carbon electrode and the drug-loaded patch to form an osmotic current, thereby promoting drug penetration.

[0036] This example was applied to a psoriasis mouse model, and the experiment was divided into two groups, in vitro and in vivo:

[0037] 1. In vitro experiments:

[0038] ① Soak a 2.5cm×2.5cm nonwoven fabric in 60μmol·L -1 A drug-loaded patch was obtained from a solution of rhodamine 6G.

[0039] ②Cover the drug-loaded patch on the pig skin.

[0040] ③Put the sound wave patch on the drug-loaded patch to integrate them into a whole, namely the iontophoresis patch, play the sound, and activate the device.

[0041] After the experiment, it was found that 30 minutes after activating the electroosmotic patch, the penetration depth of the experimental group with the iontophoresis patch was 3 to 4 times that of the control group, and the drug release amount in the electroosmotic group was also greater.

[0042] 2. In vitro experiments

[0043] ① Soak a 2.5 cm × 2.5 cm nonwoven fabric in 0.5 mg mL –1 The dexamethasone solution is obtained in the drug-loaded patch.

[0044] ② Cover the drug-loaded patch on the psoriasis skin area of ​​the mouse.

[0045] ③ Place the sonic patch on the drug-loaded patch to form a whole, namely the iontophoresis patch, play the sound, and activate the device for 30 minutes.

[0046] After five days of cycling, the mice in the experimental group with the iontophoresis patch returned to normal, while the mice in the control group still showed obvious symptoms of psoriasis.

[0047] The following is the preparation method of the iontophoresis patch:

[0048] Step 1: Microcircuit preparation: First, design a circuit template, then use etching technology to etch the required circuit on a polyimide substrate, exposing pads for subsequent soldering of electronic components.

[0049] Step 2: Fabrication of Helmholtz single-hole resonant cavity. Design the structure of the single-hole resonant cavity and use hard resin material for 3D printing. The resonant cavity is cylindrical as a whole, with a slightly arched top to better receive the sound waves. The top section is trapezoidal to better collect the sound waves. There is a circular through hole on the top to concentrate the sound wave energy on the lead zirconate titanate piezoelectric sheet. At the same time, the base of the resonant cavity reserves a circuit card slot to integrate the microcircuit in the resonant cavity.

[0050] Step 3: Assembling: The piezoelectric sheet, microcircuit and carbon electrode were integrated by reflow soldering technology, packaged by PDMS, and cured at 80°C for 2 hours to obtain an acoustic wave patch.

[0051] Step 4: Integration: The drug to be released is prepared into a solution, and the non-woven fabric is soaked to obtain a drug-loaded patch. The acoustic wave patch is exposed on the drug-loaded patch to obtain an iontophoresis patch.

[0052] It is to be understood that the present invention is described by some embodiments, and it is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims

1. A wireless battery-free iontophoresis patch for skin care, characterized in that: The iontophoresis patch comprises an acoustic wave patch (1) and a drug-carrying patch (2); The acoustic wave patch (1) comprises a Helmholtz single-hole resonant cavity (1-1), a lead zirconate titanate piezoelectric sheet (1-2), a microcircuit (1-3), and a carbon electrode (1-4); the Helmholtz single-hole resonant cavity (1-1) is cylindrical in shape as a whole, the top cross-section is arc-shaped or trapezoidal, and there is a circular hole in the center of the top; below the Helmholtz single-hole resonant cavity (1-1) is the lead zirconate titanate piezoelectric sheet (1-2), and the lead zirconate titanate piezoelectric sheet (1-2) comprises lead zirconate titanate piezoelectric ceramics, a silver electrode , copper substrate, the lower surface of the lead zirconate titanate piezoelectric ceramic is a copper substrate, and the upper surface is a silver electrode, wherein the size of the silver electrode is consistent with that of the lead zirconate titanate piezoelectric ceramic, and the size of the copper substrate is larger than that of the lead zirconate titanate piezoelectric ceramic; a microcircuit is located below the lead zirconate titanate piezoelectric sheet, and two carbon electrodes (1-4) are connected below the microcircuit, serving as the positive and negative electrodes of the microcircuit output respectively; an electrical connection is formed between the lead zirconate titanate piezoelectric sheet (1-2), the microcircuit (1-3), and the carbon electrode (1-4); The drug-carrying patch (2) comprises a non-woven fabric (2-1) soaked in a phosphate buffered saline solution and a non-woven fabric (2-2) soaked in an ionic drug solution. When in use, the non-woven fabric soaked in the ionic drug solution is attached to a carbon electrode having the same electrical properties as the ionic drug, and the non-woven fabric soaked in the phosphate buffered saline solution is attached to another carbon electrode.

2. A wireless battery-free iontophoresis patch for skin care according to claim 1, characterized in that: The microcircuit (1-3) comprises a polyimide substrate (1-3-1), an upper piezoelectric pad (1-3-2), a lower piezoelectric pad (1-3-3), a rectifier circuit (1-3-4), and a carbon electrode pad (1-3-5); the microcircuit is formed on the polyimide substrate (1-3-1), and an upper piezoelectric pad is provided at the center of the upper surface of the polyimide substrate (1-3-1), and the size of the upper piezoelectric pad is smaller than the size of the polyimide substrate; the lower surface of the polyimide substrate is provided with two carbon electrode pads, a rectifier circuit, and a lower piezoelectric pad; the upper piezoelectric pad is connected to the copper substrate, the lower piezoelectric pad is connected to the silver electrode of the lead zirconate titanate piezoelectric sheet, the upper piezoelectric pad and the lower piezoelectric pad are connected to the rectifier circuit, and the carbon electrode pads are respectively connected to two carbon electrodes.

3. A wireless battery-free iontophoresis patch for skin care according to claim 2, characterized in that: The microcircuit is encapsulated with polydimethylsiloxane.

4. A wireless battery-free iontophoresis patch for skin care according to claim 2, characterized in that: The upper piezoelectric pad is connected to the copper substrate of the lead zirconate titanate piezoelectric sheet through a conductive solder paste, and the lower piezoelectric pad is connected to the silver electrode of the lead zirconate titanate piezoelectric sheet through a wire.

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