Direct current stimulation hydrogel dressing

Abstract

The utility model discloses a direct current stimulation hydrogel dressing plaster, which comprises a substrate layer, a conducting layer and a hydrogel layer from bottom to top in sequence, the substrate layer is a polymer flexible substrate layer, the conducting layer is a circular interdigital structure formed by electrode materials, the electrode materials comprise a working electrode and a counter electrode, and the working electrode is a flexible electrode. The lower end part of the working electrode and the lower end part of the counter electrode extend to the lower end of the substrate layer, the upper end part of the working electrode is provided with a working electrode interdigital strip, and the upper end part of the counter electrode is provided with a counter electrode interdigital strip; the working electrode interdigital strips and the counter electrode interdigital strips are arranged on the substrate layer in the form of concentric circles surrounding each other. The hydrogel dressing is combined with an exogenous electric field for intervention, so that wound healing is accelerated.

Description

Technical Field

[0001] The utility model belongs to biomedical engineering, and particularly relates to a direct current stimulated hydrogel dressing patch. Background Technique

[0002] The skin is the largest organ of the human body, accounting for about 15% of the total body weight. It is the first barrier for the human body to contact the external environment and an important barrier for the human body to resist external stimuli. According to statistics, tens of millions of people worldwide suffer from skin trauma due to accidents, surgeries or diseases every year. Skin wound healing, as a highly dynamic and complex process, its healing speed depends on the orderly activation and interaction of various cells in a temporal and spatial order. In most cases, skin wounds can heal on their own. However, in some populations, such as the elderly, obese people, and diabetic patients, abnormal metabolism often leads to abnormal wound healing due to their own metabolic abnormalities. Such wounds that cannot heal on their own for a long time are called chronic wounds. The existence of chronic wounds means an increased risk of infection, and in severe cases, serious consequences such as amputation will also be faced, seriously affecting the quality of life of patients.

[0003] Currently, the treatment measures for such chronic wounds mainly include rapid debridement, local dressings, negative pressure treatment, hyperbaric oxygen treatment, bioengineering therapy, decellularization therapy, and stem cell therapy, etc. Among them, hydrogel dressings have attracted much attention from researchers because they can provide a moist healing environment for wounds, are not easily adhered to new tissues, and prevent bacterial infections. However, most of the current hydrogel dressings on the market only act as a physical protection during the wound repair process and cannot effectively stimulate the endogenous cells around the wound to promote wound healing.

[0004] In the normal skin barrier, there is an endogenous electric field of 10 - 60 mV between the epidermis and the subepidermis, which is called the transepithelial potential (TEP). This transepithelial potential difference mainly maintains the frequent depolarization and repolarization of epidermal cells through ion exchange on the cell membrane of epidermal cells. The transepithelial potential difference plays an important role in the process of wound re-epithelialization. When the skin is damaged, this transepithelial potential (TEP) will increase greatly around the wound, and the damaged epithelial cells cannot maintain the normal TEP, resulting in a short circuit of TEP, thus generating a positive current flowing towards the wound. Currently, many in vitro and in vivo experiments have proved that an externally applied electric field can simulate this endogenous electric field around the wound and promote wound healing. Its specific mechanism mainly includes promoting epithelialization around the wound, fibroblast migration, and an increase in blood vessel distribution.

[0005] However, there are the following disadvantages in using hydrogel patches alone and electrical stimulation alone: (1) Using hydrogel patches alone cannot actively regulate the behavior of endogenous cells to promote wound healing, resulting in passive repair of the wound. (2) It is difficult to completely cover the wound with electrical stimulation alone, and some damaged tissues will still be exposed to the air, unable to effectively protect the wound from external environmental interference, and prone to subsequent infection of the wound, affecting the wound healing effect. (3) When electrical stimulation is applied to the wound, the long-term direct contact between the electrode and the skin at the wound site may cause chemical reactions at both ends of the electrode, resulting in secondary damage to skin cells and tissues. Summary of the Invention

[0006] To solve the deficiencies in the prior art, the objective of the present invention is to provide a direct current stimulated hydrogel dressing patch.

[0007] The specific technical solutions are as follows:

[0008] The present utility model provides a direct current stimulated hydrogel dressing patch, which sequentially includes a base layer, a conductive layer, and a hydrogel layer from bottom to top. The base layer is a polymer flexible base layer. The conductive layer is a circular interdigital structure formed by electrode materials. The electrode materials include a working electrode and a counter electrode. The lower ends of the working electrode and the counter electrode extend to the lower end of the base layer. The upper end of the working electrode is provided with working electrode interdigital bars, and the upper end of the counter electrode is provided with counter electrode interdigital bars. The working electrode interdigital bars and the counter electrode interdigital bars are arranged on the base layer in the form of concentric circles that surround each other.

[0009] Further, the base layer is a polyimide base layer.

[0010] Further, the conductive layer is successively a copper layer, a nickel layer, and a gold layer from bottom to top.

[0011] Further, the thickness of the conductive layer is 0.1 - 0.2 mm.

[0012] Further, the diameter of the circular interdigital structure is 0.9 cm.

[0013] Further, the hydrogel layer is a square structure with dimensions of 1.0 - 1.2 cm × 1.0 - 1.2 cm.

[0014] The beneficial effects of the present utility model are:

[0015] The direct current-stimulated hydrogel dressing patch provided by the present utility model combines a hydrogel dressing with an exogenous electric field intervention to accelerate wound healing. On the one hand, the hydrogel layer can isolate the wound from the external environment, playing a role in protecting the wound, antibacterial, and promoting wound healing. On the other hand, the direct current stimulation generated by the circular interdigitated electrodes formed by the base layer and the conductive layer can enhance the endogenous electric field distribution around the wound, improve the function of cells, and accelerate cell migration and wound healing. Compared with the control group using only the hydrogel dressing, the treatment with the electro-stimulated hydrogel dressing significantly accelerates the wound healing rate. Brief Description of the Drawings

[0016] Figure 1 It is a schematic cross-sectional layer diagram of the direct current-stimulated hydrogel dressing patch of the present utility model. Among them, 1 is the base layer, 2 is the conductive layer, and 3 is the hydrogel layer.

[0017] Figure 2 It is a schematic diagram of the circular interdigitated electrode of the present utility model. Among them, 1 is the base layer, 4 is the counter electrode, 5 is the working electrode, 6 is the counter electrode finger bar, 7 is the working electrode finger bar, and 8 is the gasket. Detailed Embodiments

[0018] To better understand the present utility model, the present utility model will be further described with reference to the following embodiments and drawings. The embodiments are only for explanation and do not limit the present utility model in any way. In the embodiments, all the original reagent materials can be obtained commercially. The experimental methods without specific conditions are the conventional methods and conventional conditions well known in the art, or the conditions recommended by the instrument manufacturer.

[0019] Embodiment 1

[0020] This embodiment provides a direct current-stimulated hydrogel dressing patch. The schematic cross-sectional layer diagram is as Figure 1 shown. The direct current-stimulated hydrogel dressing patch sequentially includes a base layer 1, a conductive layer 2, and a hydrogel layer 3 from bottom to top. Among them, the base layer 1 is a polymer flexible base layer, and the conductive layer 2 is a circular interdigitated structure formed by electrode materials. The electrode materials include a working electrode and a counter electrode. The circular interdigitated electrode formed by the base layer 1 and the conductive layer 2 is as Figure 2 shown. The lower ends of the working electrode 5 and the counter electrode 4 extend to the lower end of the base layer 1. The upper end of the working electrode 5 is provided with a working electrode finger bar 7, and the upper end of the counter electrode 4 is provided with a counter electrode finger bar 6. The working electrode finger bar and the counter electrode finger bar are arranged on the base layer 1 in a concentric circle form surrounding each other.

[0021] In a specific embodiment, gaskets 8 are provided at the lower ends of the working electrode 5 and the counter electrode 4.

[0022] In a specific embodiment, the base layer 1 is a polyimide base layer.

[0023] In a specific embodiment, the conductive layer 2 is, from bottom to top, a copper layer, a nickel layer, and a gold layer in sequence.

[0024] In a specific embodiment, the thickness of the conductive layer 2 is 0.1 - 0.2 mm.

[0025] In a specific embodiment, the diameter of the circular interdigital structure is 0.9 cm.

[0026] In a specific embodiment, the hydrogel layer is a square structure with dimensions of 1.0 - 1.2 cm × 1.0 - 1.2 cm.

[0027] Example 2

[0028] This example provides a direct current-stimulated hydrogel dressing patch. The schematic cross-sectional layer diagram is as Figure 1 shown. The direct current-stimulated hydrogel dressing patch sequentially includes a base layer 1, a conductive layer 2, and a hydrogel layer 3 from bottom to top. Among them, the base layer 1 is a polymer flexible base layer, and the conductive layer 2 is a circular interdigital structure formed by electrode materials. The electrode materials include a working electrode and a counter electrode. The circular interdigital electrode formed by the base layer 1 and the conductive layer 2 is as Figure 2 shown. The lower end of the working electrode 5 and the lower end of the counter electrode 4 extend to the lower end of the base layer 1. The upper end of the working electrode 5 is provided with working electrode interdigital strips 7, and the upper end of the counter electrode 4 is provided with counter electrode interdigital strips 6. The working electrode interdigital strips and the counter electrode interdigital strips are arranged on the base layer 1 in the form of concentric circles that surround each other. The lower ends of the working electrode 5 and the counter electrode 4 are provided with gaskets 8. The base layer 1 is a polyimide base layer. The conductive layer 2 is one or several of copper, nickel, and gold. The thickness of the conductive layer 2 is 0.15 mm. The diameter of the circular interdigital structure is 0.9 cm. The hydrogel layer is a square structure with dimensions of 1.0 cm × 1.0 cm.

[0029] The direct current-stimulated hydrogel dressing patch of this example is used to treat the full-thickness wounds of the skin of SD rats, and a hydrogel dressing identical to the dressing patch is used as a control. The specific steps are as follows:

[0030] Ten male SD rats (age: 7 - 9 weeks) were used and raised in a standardized environment. They were anesthetized by inhaling isoflurane (1.0 L / min, concentration: 3%). The hair on the back area of the rats was shaved off, and the skin was disinfected with povidone iodine and alcohol cotton pads. Two full - thickness wounds with an area of approximately 10×10 mm were made on each side (left and right) of the back of the SD rats using autoclaved ophthalmic scissors. The ten rats were randomly divided into two groups (n = 5): the control group (hydrogel dressing) and the hydrogel dressing with direct current stimulation of this example (covering the wound with the dressing and simultaneously giving direct current stimulation treatment, the electric stimulation intensity was 200 mV / mm). The wound areas were recorded on the 0th, 3rd, 6th, 9th, 12th, 15th, and 18th days, and the healing conditions of the wounds in the two groups were compared. The wound recovery process was measured and statistically analyzed. The experimental results showed that the use of hydrogel wound dressings combined with electrical stimulation could accelerate wound healing, indicating that the hydrogel could form an external electric field around the wound by applying electrical stimulation, effectively simulating the physiological internal electric field for epidermal cell healing.

[0031] Obviously, the above - mentioned embodiments are only examples clearly described and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the creation of the present utility model.

Claims

1. A direct current stimulation hydrogel dressing, characterized in that: The direct current stimulation hydrogel dressing patch includes a base layer, a conductive layer and a hydrogel layer from bottom to top, wherein the base layer is a polymer flexible base layer, the conductive layer is a circular interdigitated structure formed by electrode material, the electrode material includes a working electrode and a counter electrode, the lower end of the working electrode and the lower end of the counter electrode extend to the lower end of the base layer, the upper end of the working electrode is provided with a working electrode interdigitated strip, the upper end of the counter electrode is provided with a counter electrode interdigitated strip, and the working electrode interdigitated strip and the counter electrode interdigitated strip are arranged on the base layer in the form of concentric circles surrounding each other.

2. The direct current stimulation hydrogel dressing according to claim 1, characterized in that: The base layer is a polyimide base layer.

3. The direct current stimulation hydrogel dressing according to claim 1, characterized in that: The conductive layers are copper layer, nickel layer and gold layer from bottom to top.

4. The direct current stimulation hydrogel dressing according to claim 1, characterized in that: The thickness of the conductive layer is 0.1-0.2 mm.

5. The direct current stimulation hydrogel dressing according to claim 1, characterized in that: The diameter of the circular interdigitated structure is 0.9 cm.

6. The direct current stimulation hydrogel dressing according to claim 1, characterized in that: The hydrogel layer is a square structure with a size of 1.0-1.2 cm×1.0-1.2 cm.

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