Magnesium-containing hydrogel patch and preparation method thereof

Abstract

The magnesium-containing hydrogel patch and the preparation method thereof are characterized in that the magnesium-containing hydrogel patch comprises a hydrogel layer and a backing layer. The main component of the hydrogel layer is a polydopamine-polyacrylic acid copolymer, the hydrogel layer contains magnesium ions, and the concentration of the magnesium ions is 40 wt%-45 wt%; the hydrogel layer is uniformly coated on the back lining layer. The preparation method of the hydrogel patch comprises the following steps: preparing an acrylic acid aqueous solution from sodium acrylate and dopamine hydrochloride, preparing magnesium-containing hydrogel, and coating the hydrogel.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and particularly to a magnesium-containing hydrogel patch and a preparation method thereof. Background Art

[0002] Magnesium sulfate at a concentration of 50% is a hypertonic solution for tissue fluid. Local wet compress can produce a high osmotic pressure, causing the tissue edema fluid at the swollen site to be sucked out and the swelling to subside in a short time. Clinically, 50% magnesium sulfate gauze is commonly used for wet compress to treat phlebitis. However, when using 50% magnesium sulfate gauze for wet compress, the water evaporates relatively quickly, the effective wet compress time is short, and the operation is troublesome. Abroad, magnesium chloride aqueous solution is also known as magnesium oil health product, and is often made into magnesium oil paste and applied to the skin to absorb magnesium ions through the skin to supplement the magnesium ions required by the human body. However, it is difficult for magnesium ions to be absorbed through the skin. It is difficult to penetrate the stratum corneum of the skin and mainly absorbs through hair follicles. And the magnesium oil health product stays on the skin surface for a short time, and the magnesium ions absorbed through the skin are limited.

[0003] Due to its high water content, good water retention, excellent biocompatibility, and microstructure similar to the extracellular matrix, hydrogel materials are considered to be the biological functional materials closest to living tissues. Among them, polyacrylic acid hydrogel is one of the most widely studied hydrogels. Polyacrylic acid hydrogel contains abundant carboxyl groups, has a strong interaction with water molecules, has an extremely high swelling rate in water, has high water absorption performance, and can be applied to the skin for a long time.

[0004] Adding a magnesium salt solution to the acrylic acid hydrogel system and preparing a hydrogel patch can extend the time of transdermal absorption of magnesium ions. However, high-concentration magnesium sulfate has very poor compatibility with sodium polyacrylate hydrogel and is difficult to crosslink. Once crosslinked, the reaction is rapid and it cannot be coated, so production cannot be carried out. On the other hand, polyacrylic acid hydrogel is sensitive to pH and has poor salt tolerance. Therefore, introducing a high-concentration magnesium salt solution will cause the network structure of the hydrogel to be damaged, the elasticity of the gel to become poor, and the water absorption to become poor. Eventually, magnesium salt crystals will precipitate, so that the functions of reducing swelling, anti-inflammatory, pain relief, and supplementing magnesium ions cannot be exerted. Summary of the Invention

[0005] In view of the deficiencies of the prior art, the present invention provides a magnesium-containing hydrogel patch that can be applied to the skin for a long time, which is characterized in that it includes:

[0006] A hydrogel layer, the main component of the hydrogel layer is a polydopamine-polyacrylic acid copolymer, the hydrogel layer contains magnesium ions, and the concentration of the magnesium ions is 40wt% - 45wt%; a backing layer, and the hydrogel layer is uniformly coated on the backing layer.

[0007] Further, for the magnesium-containing hydrogel patch as described above, the thickness range of the hydrogel layer is 5 - 10mm.

[0008] Further, the magnesium-containing hydrogel patch as described above, wherein the backing layer is non-woven fabric.

[0009] Further, the magnesium-containing hydrogel patch as described above, wherein the magnesium-containing hydrogel patch includes a release layer, the release layer is attached to the hydrogel layer, and the release layer is a release film coated with silicone oil.

[0010] Further, the magnesium-containing hydrogel patch as described above, wherein the material of the release film is thermoplastic polyurethane.

[0011] Further, the magnesium-containing hydrogel patch as described above, wherein the thickness of the release film is 1 mm.

[0012] The present invention also relates to a preparation method of the above-mentioned magnesium-containing hydrogel patch, which is characterized by including:

[0013] Prepare an acrylic acid aqueous solution, add sodium acrylate to deionized water, adjust the pH to 6.0 - 7.0, and then add auxiliary materials, dopamine hydrochloride and magnesium salt powder; wherein the mass ratio of sodium acrylate is 2 - 5 wt%, the mass ratio of dopamine hydrochloride is 2 - 5 wt%, and the mass of deionized water is the same as the mass of the magnesium salt powder;

[0014] Prepare a hydrogel, add a cross-linking agent and an initiator to the acrylic acid aqueous solution, stir under the condition of 35°C - 45°C, and let it stand and age after stirring to obtain a stable hydrogel with the main component of polydopamine-polyacrylic acid copolymer. The hydrogel contains magnesium ions, and the concentration of the magnesium ions is 40 wt% - 45 wt%.

[0015] Coat the magnesium-containing hydrogel on the backing.

[0016] Further, in the preparation method as described above, when preparing the acrylic acid aqueous solution, the mass ratio of the magnesium salt powder is 40 wt% - 45 wt%.

[0017] Further, in the preparation method as described above, the cross-linking agent is sodium hyaluronate and methylene bisacrylamide, and the initiator is ammonium persulfate; after the cross-linking agent and the initiator are added to the acrylic acid aqueous solution, the total mass ratio of the cross-linking agent and the initiator is 1 - 2 wt%.

[0018] Further, in the preparation method as described above, the mass ratio of sodium hyaluronate, methylene bisacrylamide and ammonium persulfate is 1:1:2.

[0019] The advantages of the present invention are:

[0020] 1. The magnesium-containing hydrogel patch of the present invention can be applied to the skin for a long time, effectively retaining moisture, enabling magnesium ions to dissolve in the hydrogel for a long time and exist on the skin surface, thus prolonging the transdermal absorption time of magnesium ions.

[0021] 2. The present invention uses dopamine hydrochloride to modify acrylic hydrogel to obtain a stable hydrogel with the main component of poly(dopamine-acrylic acid) copolymer. Utilizing the chelating ability of dopamine with magnesium ions, the hydrogel can crosslink smoothly with high-concentration magnesium sulfate, maintaining the network structure of the hydrogel and ensuring its water absorption. At the same time, the hydrogel provides a solution environment for magnesium salts, enabling magnesium elements to exist in the hydrogel in the form of magnesium ions, and the concentration of magnesium ions reaches 40wt% - 45wt%.

[0022] 3. In summary, the magnesium-containing hydrogel patch of the present invention not only increases the concentration of magnesium ions but also prolongs the transdermal absorption time of magnesium ions. Therefore, it can significantly increase the total amount of transdermally absorbed magnesium ions and fully exert the functions of detumescence, anti-inflammation, pain relief, and magnesium ion supplementation. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a flow chart of the preparation method of the magnesium-containing hydrogel patch of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0025] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "one side", "one end", "one side", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present invention. In addition, in the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0026] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] It should also be understood that the terms used in the description of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the description of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms.

[0028] It should be further understood that the term " / and" used in the description of the present invention and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0029] The present invention discloses a magnesium-containing hydrogel patch, which is characterized by comprising a hydrogel layer and a backing layer, and the hydrogel layer is uniformly coated on the backing layer.

[0030] The main component of the hydrogel layer is a poly-dopamine-polyacrylic acid copolymer. The hydrogel layer contains magnesium ions, and the concentration of the magnesium ions is 40 wt% - 45 wt%. The thickness range of the hydrogel layer is 5 - 10 mm.

[0031] The backing layer is non-woven fabric.

[0032] Preferably, the magnesium-containing hydrogel patch includes a release layer, which is attached to the hydrogel layer to protect the adhesiveness of the hydrogel layer in the unused state. The release layer is a silicone oil-coated release film, the material of the release film is thermoplastic polyurethane, and the thickness of the release film is 1 mm.

[0033] Furthermore, the present invention also provides a preparation method for the above-mentioned magnesium-containing hydrogel patch, as Figure 1 shown, including the following steps:

[0034] Prepare an aqueous acrylic acid solution, add sodium acrylate to deionized water, adjust the pH to 6.0 - 7.0, and then add auxiliary materials, dopamine hydrochloride, and magnesium salt powder; wherein the mass ratio of the sodium acrylate is 2 - 5 wt%, the mass ratio of the dopamine hydrochloride is 2 - 5 wt%, the mass of the deionized water is the same as the mass of the magnesium salt powder; the auxiliary materials include glycerol, menthol, lavender oil, and methyl salicylate.

[0035] To prepare a magnesium-containing hydrogel, a crosslinking agent and an initiator are added to an aqueous acrylic acid solution, and the mixture is stirred under the condition of 35°C to 45°C. After stirring, it is allowed to stand and age to obtain a stable hydrogel mainly composed of a polydopamine-polyacrylic acid copolymer. The hydrogel contains magnesium ions, and the concentration of the magnesium ions is 40 wt% to 45 wt%. The crosslinking agent is sodium hyaluronate (HA) and N,N'-methylenebisacrylamide (MBA), but not limited thereto; the initiator is ammonium persulfate, but not limited thereto.

[0036] Coat the magnesium-containing hydrogel by coating the hydrogel on a backing.

[0037] The following combines specific examples to detail the magnesium-containing hydrogel of the present invention and its preparation method.

[0038] Example 1:

[0039] In the hydrogel layer of the magnesium-containing hydrogel patch of this example, the concentration of magnesium ions is 40 wt% to 45 wt%. The detailed preparation method of Example 1 is as follows:

[0040] Step 1, prepare an aqueous acrylic acid solution:

[0041] Weigh acrylate sodium with a mass ratio of 2 wt% to 5 wt%, deionized water with a mass ratio of 40 wt% to 45 wt%, glycerol with a mass ratio of 0.001 wt% to 0.01 wt%, menthol with a mass ratio of 0.01 wt% to 0.02 wt%, lavender oil with a mass ratio of 0.02 wt% to 0.05 wt%, methyl salicylate with a mass ratio of 0.05 wt% to 0.1 wt%, and dopamine hydrochloride with a mass ratio of 2 wt% to 5 wt%. Finally, weigh anhydrous magnesium chloride powder or anhydrous magnesium sulfate powder with the same mass as the deionized water. First, add the weighed acrylic acid to the deionized water and stir evenly; then slowly drop 5 - 10 mol / L sodium hydroxide solution until the pH is 6.0 - 7.0; then add glycerol, menthol, lavender oil, methyl salicylate, and dopamine hydrochloride in sequence. Finally, add the magnesium salt powder with the same mass as the deionized water to prepare the aqueous acrylic acid solution. The magnesium salt powder is anhydrous magnesium chloride or anhydrous magnesium sulfate.

[0042] Step 2, prepare the hydrogel. Add HA, MBA, and APS with a mass ratio of 1:1:2 to the aqueous acrylic acid solution, and the total mass of the three after addition accounts for 1% - 2% of the total mass of the solution. Stir the aqueous acrylic acid solution added with HA, MBA, and APS within the temperature range of 35 - 45°C for 2 - 6 h, and after stirring, allow it to stand and age for 24 h to obtain a hydrogel containing magnesium ions, where the mass percentage of magnesium ions is 40% - 45%.

[0043] Step 3: Coating the magnesium-containing hydrogel. Coat the magnesium-containing hydrogel on the backing layer with a coating thickness of 5 - 10 mm. Finally, attach a release film on the hydrogel as protection. The release film is a silicone-coated release film made of thermoplastic polyurethane with a thickness of 1 mm.

[0044] Example 2:

[0045] In this example, when preparing the aqueous acrylic acid solution, the mass ratios of the raw materials weighed are as follows: the mass ratio of sodium acrylate is 4 wt%, the mass ratio of deionized water is 45 wt%, the mass ratio of glycerol is 0.01 wt%, the mass ratio of menthol is 0.02 wt%, the mass ratio of lavender oil is 0.05 wt%, the mass ratio of methyl salicylate is 0.05 wt%, the mass ratio of dopamine hydrochloride is 4 wt%, and the mass ratio of anhydrous magnesium chloride powder or anhydrous magnesium sulfate powder is 45 wt%. The concentration of the sodium hydroxide solution used to adjust the pH when preparing the aqueous acrylic acid solution is 10 mol / L.

[0046] In the preparation of the hydrogel in this example, the total mass of HA, MBA, and APS added accounts for 1.87% of the total mass of the solution. The aqueous acrylic acid solution added with HA, MBA, and APS is stirred at a temperature of 40°C for 6 h, and after stirring, it is aged for 24 h to obtain a hydrogel containing 45 wt% magnesium ions.

[0047] In this example, the coating thickness of the hydrogel is 8 mm.

[0048] The rest are the same as in Example 1.

[0049] Example 3:

[0050] In this example, the mass ratio of acrylic acid added when preparing the aqueous acrylic acid solution is 3 wt%, and the mass ratio of dopamine hydrochloride is 5 wt%. The rest are the same as in Example 2.

[0051] The magnesium ion concentration in the hydrogel layer of the finally prepared magnesium-containing hydrogel patch is 45 wt%.

[0052] The advantages of the present invention are as follows:

[0053] 1. The magnesium-containing hydrogel patch of the present invention can be applied to the skin for a long time, effectively retaining moisture, enabling magnesium ions to dissolve in the hydrogel for a long time and exist on the skin surface, thus prolonging the transdermal absorption time of magnesium ions.

[0054] 2. The present invention uses dopamine hydrochloride to modify acrylic hydrogel to obtain a stable hydrogel with the main component being poly-dopamine-polyacrylic acid copolymer. By utilizing the chelating ability of dopamine with magnesium ions, the hydrogel can crosslink smoothly with high-concentration magnesium sulfate, maintaining the network structure of the hydrogel and ensuring its water absorption. At the same time, the hydrogel provides a solution environment for the magnesium salt, enabling magnesium elements to exist in the hydrogel in the form of magnesium ions, and the concentration of magnesium ions reaches 40wt% - 45wt%.

[0055] 3. In summary, the magnesium-containing hydrogel patch of the present invention not only increases the concentration of magnesium ions but also prolongs the transdermal absorption time of magnesium ions. Therefore, it can significantly increase the total amount of transdermally absorbed magnesium ions, giving full play to the functions of detumescence, anti-inflammation, pain relief, and magnesium ion supplementation.

[0056] The above are only the preferred embodiments of the present invention and do not impose any formal limitations on the present invention. Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art, within the scope of the technical solution of the present invention, can make some changes or modifications to equivalent embodiments by using the disclosed technical content. However, as long as it does not depart from the technical solution of the present invention, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A magnesium-containing hydrogel patch, characterized in that, Comprising: A hydrogel layer, the main component of the hydrogel layer being a polydopamine-polyacrylic acid copolymer, the hydrogel layer containing magnesium ions, and the concentration of the magnesium ions being 40 wt% - 45 wt%; A backing layer, the hydrogel layer being uniformly coated on the backing layer.

2. The magnesium-containing hydrogel patch according to claim 1, wherein The thickness range of the hydrogel layer is 5 - 10 mm.

3. The magnesium-containing hydrogel patch according to claim 1, wherein The backing layer is non-woven fabric.

4. The magnesium-containing hydrogel patch according to any one of claims 1 to 3, wherein The magnesium-containing hydrogel patch includes a release layer, the release layer being attached to the hydrogel layer, and the release layer being a release film coated with silicone oil.

5. The magnesium-containing hydrogel patch according to claim 4, characterized in that, The material of the release film is thermoplastic polyurethane.

6. The magnesium-containing hydrogel patch as described in claim 5, wherein The thickness of the release film is 1 mm.

7. A method for preparing a magnesium-containing hydrogel patch as described in claims 1-6, characterized in that, Including, Prepare an aqueous acrylic acid solution, add sodium acrylate to deionized water, adjust the pH to 6.0 - 7.0, and then add auxiliary materials, dopamine hydrochloride and magnesium salt powder; wherein the mass ratio of sodium acrylate is 2 - 5 wt%, the mass ratio of dopamine hydrochloride is 2 - 5 wt%, and the mass of deionized water is the same as the mass of the magnesium salt powder; Prepare a hydrogel, add a cross-linking agent and an initiator to the aqueous acrylic acid solution, stir under the condition of 35°C - 45°C, and stand for aging after stirring to obtain a stable hydrogel with the main component of polydopamine-polyacrylic acid copolymer, the hydrogel containing magnesium ions, and the concentration of the magnesium ions being 40 wt% - 45 wt%; Coat the magnesium-containing hydrogel on the backing.

8. The preparation method according to claim 7, characterized in that, When preparing the aqueous acrylic acid solution, the mass ratio of the magnesium salt powder is 40 wt% - 45 wt%.

9. The preparation method according to claim 7, characterized in that, The cross-linking agent is sodium hyaluronate and methylene bisacrylamide, and the initiator is ammonium persulfate; after the cross-linking agent and the initiator are added to the aqueous acrylic acid solution, the total mass ratio of the cross-linking agent and the initiator is 1 - 2 wt%.

10. The preparation method of the magnesium-containing hydrogel patch according to claim 9, characterized in that, The mass ratio of sodium hyaluronate, methylene bisacrylamide and ammonium persulfate is 1:1:2.

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