Aromatic soluble polymer microneedle as well as preparation method and application thereof

Abstract

The invention relates to an aromatic soluble polymer microneedle as well as a preparation method and application thereof. The preparation method comprises the following steps: adding a zinc acetate hexahydrate aqueous solution and a Tris buffer solution into a eugenol-curcumin mixed ethanol solution to obtain self-assembled carrier-free nanoparticles containing eugenol and curcumin; and dissolving the nano-particles in a soluble hyaluronic acid solution, drying in a microneedle mold, and demolding to obtain the aromatic soluble polymer microneedle. The structure of the aromatic soluble polymer microneedle is that self-assembled carrier-free nanoparticles are wrapped in a soluble hyaluronic acid microneedle. Compared with the prior art, the aromatic soluble polymer microneedle prepared by the invention can overcome skin barrier and quickly absorb moisture and dissolve so as to promote the transdermal absorption effect of active substances; a perfume delivery system is constructed by using the soluble polymer microneedle, so that the biocompatibility is improved, the slow release control capability of the perfume can be effectively enhanced, and a new path is opened up for clinical application of inflammatory diseases.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to an aromatic soluble polymer microneedle and a preparation method and application thereof. Background Art

[0002] Spices are substances whose aroma can be sensed by smell or taste. They play an important role in many fields such as personal care, household products, cosmetics, perfume, textiles, food industry, medicine, tobacco and alcohol manufacturing, and health care. Spices are generally regarded as safe and reliable, and can even be used as an alternative to traditional treatment methods in some cases. Scientific research has confirmed that some spices have the potential to relieve inflammatory diseases. They not only have antibacterial and anti-inflammatory physiological effects, but also provide significant benefits at the psychological level, such as relieving tension, improving mental state, and effectively reducing anxiety and negative emotions. It is particularly noteworthy that the significant advantages of spices in regulating the immune system are gradually attracting widespread interest and attention from all walks of life. However, as volatile organic small molecule compounds, spices also face some inherent challenges: they have poor water solubility, are easy to volatilize, and are prone to chemical reactions such as cyclization, oxidation and hydrolysis under high temperature, light or specific acid-base environments. These problems directly lead to the shortening of the action time of spices in the matrix, the reduction of dispersion uniformity, the deterioration of aroma quality and the attenuation of biological activity, thereby limiting their scope of application.

[0003] Microneedle drug delivery is a new type of transdermal drug delivery method. It uses micron-level needles to penetrate the skin barrier and deliver drugs directly to the epidermis and dermis in a non-invasive and painless manner. Microneedles can significantly improve the transdermal delivery efficiency of drugs, especially for those drugs that are difficult to deliver through traditional skin patches, such as peptides, proteins and nanovaccines. Polymer-based soluble microneedles have attracted much attention due to their superior drug delivery ability and the characteristics of no medical waste residue after administration. The tip of the nanoparticles can penetrate the epidermis and deliver the drug to a certain depth of the skin, and the penetration depth of less than 750μm hardly causes bleeding or pain. Although microneedles are often used to deliver synthetic drugs, some drugs have limitations such as poor efficacy, long course of treatment, and large side effects in the treatment of diseases. Therefore, people began to seek synthetic drug substitutes with equal therapeutic potential - spices. Spices can not only play an antibacterial and anti-inflammatory physiological role, but also have significant effects in regulating the immune system. However, spices still have medical defects such as fast release, lack of cell specificity, low cytoplasmic transmission efficiency, and fast clearance of the immune system when used clinically.

[0004] There is currently no report on the use of soluble polymer microneedles to construct a fragrance delivery system. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and to provide a fragrance-soluble polymer microneedle and its preparation method and application. The prepared polymer microneedle has the ability to quickly absorb moisture and dissolve after penetrating the epidermis of the skin, and can be used to prepare sustained-release and anti-inflammatory materials.

[0006] The conceptual process of this application is as follows: nanoparticles containing eugenol and curcumin are prepared by carrier-free self-assembly technology, the carrier-free nanoparticles are dissolved in a soluble polymer solution to prepare aromatic soluble polymer microneedles, and the soluble polymer microneedles are used to construct a fragrance delivery system, which can not only improve biocompatibility, but also effectively enhance the sustained-release control ability of the fragrance, improve the stability of the fragrance, and open up a new path for the clinical application of inflammatory diseases.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] The present invention provides a method for preparing an aromatic soluble polymer microneedle, comprising the following steps:

[0009] S1, first dissolving eugenol and curcumin in ethanol respectively to obtain a eugenol ethanol solution and a curcumin ethanol solution, and then mixing the eugenol ethanol solution and the curcumin ethanol solution to obtain a eugenol-curcumin ethanol mixed solution;

[0010] S2, first dissolving zinc acetate hexahydrate in deionized water to obtain a zinc acetate hexahydrate aqueous solution, then stirring and adding the zinc acetate hexahydrate solution and Tris buffer to the eugenol-curcumin ethanol mixed solution obtained in S1, and continuing to stir at room temperature, then standing, centrifuging, washing, and vacuum freeze-drying to obtain self-assembled carrier-free nanoparticles containing eugenol and curcumin;

[0011] S3. Dissolve the self-assembled carrier-free nanoparticles containing eugenol and curcumin obtained in S2 in a soluble polymer solution, pour the solution into a polytetrafluoroethylene microneedle mold after stirring at room temperature, and demold the solution after drying to obtain aromatic soluble polymer microneedles.

[0012] Furthermore, in S1, the concentration of the curcumin ethanol solution is 5 mg / mL.

[0013] Preferably, in S1, the concentration of the eugenol ethanol solution is 4 mg / mL.

[0014] Furthermore, in S2, the concentration of zinc acetate hexahydrate is 0.2 mM.

[0015] Furthermore, in S2, the pH value of the Tris buffer is 8.0; the preparation method of the Tris buffer is: dissolve tris(hydroxymethyl)aminomethane in deionized water, add hydrochloric acid dropwise while stirring, and use a pH meter to measure the pH value of the buffer until the pH reaches 8.0, and then add deionized water to make the buffer volume 1L to obtain the Tris buffer.

[0016] Furthermore, in S3, the soluble polymer solution is a hyaluronic acid solution; the preparation method of the hyaluronic acid solution is: dissolving hyaluronic acid in deionized water, then centrifuging the solution to defoam, and waiting for the solution to become clear and transparent to obtain a soluble hyaluronic acid solution.

[0017] Preferably, the mass ratio of the hyaluronic acid to deionized water is 1:4.

[0018] Preferably, the drying time is 12 to 36 hours.

[0019] The present invention also provides an aromatic soluble polymer microneedle prepared by the above method, wherein the polymer microneedle comprises a load and a wrapping layer, wherein the load is self-assembled carrier-free nanoparticles containing eugenol and curcumin, and the wrapping layer is a soluble hyaluronic acid microneedle. The self-assembled carrier-free nanoparticles are self-assembled through hydrophobic interaction and hydrogen bond interaction and are wrapped in the soluble hyaluronic acid microneedle. This structural design enables the nanoparticles to be stably embedded in the microneedle system, thereby exerting their potential for sustained release and controlled release during transdermal drug delivery.

[0020] Furthermore, the structure of the self-assembled carrier-free nanoparticles containing eugenol and curcumin is eugenol-curcumin and Zn Ⅱ The coordination ball.

[0021] Furthermore, the average diameter of the self-assembled carrier-free nanoparticles containing eugenol and curcumin is 150 nm, and the average diameter of the self-assembled carrier-free nanoparticles containing eugenol and curcumin dispersed in an aqueous solution is 200 nm.

[0022] The present invention also provides an application of the above-mentioned aromatic soluble polymer microneedle, wherein the aromatic soluble polymer microneedle is used for preparing sustained-release and anti-inflammatory materials.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) The present invention prepares fragrance nanoparticles in one step through a carrier-free self-assembly technology. The fragrance molecules directly form nanoparticles through their own interactions, avoiding the negative effects that may be caused by the introduction of carriers, increasing the proportion of active substances, and thus improving the potential of microneedle materials to treat inflammatory diseases.

[0025] (2) The aromatic soluble polymer microneedles prepared by the present invention have the ability to quickly absorb moisture and dissolve by themselves after penetrating the skin, and will not remain in the body, thereby improving biosafety and promoting transdermal absorption of active substances, thereby achieving a slow and controllable release of fragrances inside the skin tissue. This process is not only intended to improve the user experience, but also to effectively exert the dual anti-inflammatory and antioxidant effects of microneedle materials, opening up a new path for the clinical application of inflammatory diseases. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a scanning electron micrograph of the self-assembled carrier-free nanoparticles containing eugenol and curcumin prepared in Example 1;

[0027] Figure 2 This is a particle size diagram of the self-assembled carrier-free nanoparticles containing eugenol and curcumin prepared in Example 1;

[0028] Figure 3 It is the ultraviolet absorption graph of zinc acetate hexahydrate solution, eugenol, curcumin and self-assembled carrier-free nanoparticles containing eugenol and curcumin in Example 1;

[0029] Figure 4 This is a schematic diagram of the structure of the aromatic soluble polymer microneedle prepared in Example 1;

[0030] Figure 5 This is a scanning electron microscope image of the aromatic soluble polymer microneedle prepared in Example 1;

[0031] Figure 6 The release diagram of curcumin and eugenol in a neutral environment by the aromatic soluble polymer microneedles in Application Example 1;

[0032] Figure 7 Schematic diagram of aromatic soluble polymer microneedle puncturing pig skin in Application Example 2;

[0033] Figure 8 This is a microscopic side view of the aromatic soluble polymer microneedle within 0-10 seconds after puncturing pig skin in Application Example 2;

[0034] Fig. 9 This is a diagram showing the DPPH free radical scavenging effect of the aromatic soluble polymer microneedles in Application Example 3;

[0035] Fig.10 This is a diagram showing the ABTS free radical scavenging effect of the aromatic soluble polymer microneedles in Application Example 4. DETAILED DESCRIPTION

[0036] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments. Any features such as component models, preparation methods, materials, structures or composition ratios not clearly described in this technical solution are regarded as common technical features disclosed in the prior art.

[0037] The preparation method of Tris buffer in Example 1 is: first weigh 12.11g of tris(hydroxymethyl)aminomethane and dissolve it in 950mL of deionized water, add hydrochloric acid solution dropwise while stirring, measure the pH value of the solution to 8.0 with a pH meter, and then add water to make up to 1L.

[0038] Example 1

[0039] The present invention provides a method for preparing an aromatic soluble polymer microneedle, comprising the following steps:

[0040] S1. Weigh 20 mg of eugenol and dissolve it in 5 mL of ethanol to obtain a eugenol ethanol solution. Weigh 25 mg of curcumin and dissolve it in 5 mL of ethanol to obtain a curcumin ethanol solution. Take 100 μL of each of the eugenol ethanol solution and the curcumin ethanol solution and mix them to obtain a eugenol-curcumin ethanol mixed solution.

[0041] S2, weigh 219.5 μg of zinc acetate hexahydrate and dissolve it in 5 mL of deionized water to obtain a zinc acetate hexahydrate aqueous solution, and then add 20 μL of zinc acetate hexahydrate solution and 780 μL of Tris buffer with pH = 8 to the eugenol-curcumin ethanol mixed solution obtained in S1 under high-speed stirring, and continue stirring at room temperature for 5 minutes. After the reaction is completed, the reaction solution is allowed to stand for 0.5 h, and then centrifuged and washed twice with deionized water, the supernatant is removed and vacuum freeze-dried to obtain 0.5 mg of self-assembled carrier-free nanoparticles Eug / Cur-Zn containing eugenol and curcumin. Ⅱ (ECZ);

[0042] S3, weigh 0.5g hyaluronic acid, dissolve it in 2mL deionized water and stir at room temperature, centrifuge to remove bubbles after the solution is dissolved until there are no large particles, and wait for the solution to become clear and transparent to obtain a soluble hyaluronic acid solution. Weigh 10mg of the self-assembled carrier-free nanoparticle freeze-dried powder containing eugenol and curcumin obtained in S2, dissolve it in the soluble hyaluronic acid solution, stir it at room temperature, pour it into a polytetrafluoroethylene microneedle mold, and demold it after drying for 24h to obtain the aromatic soluble polymer microneedle Eug / Cur-Zn Ⅱ @HA(ECZH).

[0043] Self-assembled carrier-free nanoparticles containing eugenol and curcumin Eug / Cur-Zn Ⅱ (ECZ) was characterized by transmission electron microscopy, such as Figure 1 As shown, the average diameter of the self-assembled carrier-free nanoparticles is 150 nm, and the whole is a uniform spherical shape.

[0044] Figure 2 Self-assembled carrier-free nanoparticles Eug / Cur-Zn containing eugenol and curcuminⅡ The particle size diagram, from Figure 2 It can be seen that Eug / Cur-Zn Ⅱ The dispersion in aqueous solution also showed a narrow size distribution with an average diameter of 200 nm and a PDI value much less than 0.2, indicating that the synthesized Eug / Cur-Zn Ⅱ More uniform.

[0045] Figure 3 The UV absorption diagram of zinc acetate hexahydrate solution, eugenol, curcumin and self-assembled carrier-free nanoparticles containing eugenol and curcumin. The final product has the characteristic peaks of eugenol and curcumin at the same time, which shows the successful loading of eugenol and curcumin. The new characteristic peak appearing near 485nm after self-assembly also proves that curcumin and Zn Ⅱ successful coordination.

[0046] Figure 4 Aromatic soluble polymer microneedle Eug / Cur-Zn Ⅱ @HA(ECZH) macromorphology, Figure 5 Eug / Cur-Zn Ⅱ @HA The microstructure of the needle tip. The combination of the two shows that the synthesized microneedle material has a distinct needle tip structure and regular morphology.

[0047] Example 2

[0048] The present invention provides a method for preparing an aromatic soluble polymer microneedle, comprising the following steps:

[0049] S1. Weigh 40 mg of eugenol and dissolve it in 10 mL of ethanol to obtain a eugenol ethanol solution. Weigh 50 mg of curcumin and dissolve it in 10 mL of ethanol to obtain a curcumin ethanol solution. Take 1 mL of each of the eugenol ethanol solution and the curcumin ethanol solution and mix them to obtain a eugenol-curcumin ethanol mixed solution.

[0050] S2, weigh 439 μg of zinc acetate hexahydrate and dissolve it in 10 mL of deionized water to obtain a zinc acetate hexahydrate aqueous solution, and then add 200 μL of zinc acetate hexahydrate solution and 7.8 mL of Tris buffer with pH = 8 to the eugenol-curcumin ethanol mixed solution obtained in S1 under high-speed stirring, and continue stirring at room temperature for 5 minutes. After the reaction is completed, the reaction solution is allowed to stand for 0.5 hours, and then centrifuged and washed twice with deionized water, the supernatant is removed and vacuum freeze-dried to obtain 5 mg of self-assembled carrier-free nanoparticles Eug / Cur-Zn containing eugenol and curcumin. Ⅱ (ECZ);

[0051] S3, weigh 0.3g hyaluronic acid, dissolve it in 1.2mL deionized water and stir at room temperature, centrifuge to remove bubbles after the solution is dissolved until there are no large particles, and wait for the solution to become clear and transparent to obtain a soluble hyaluronic acid solution. Weigh 6mg of the self-assembled carrier-free nanoparticle freeze-dried powder containing eugenol and curcumin obtained in S2, dissolve it in the soluble hyaluronic acid solution, stir it at room temperature, pour it into a polytetrafluoroethylene microneedle mold, and demold it after drying for 24h to obtain the aromatic soluble polymer microneedle Eug / Cur-Zn Ⅱ @HA(ECZH).

[0052] Application Example 1

[0053] In this application example, the aromatic soluble polymer microneedles prepared in Example 1 are applied to the controlled release of eugenol and curcumin. Ⅱ @HA was placed in a dialysis bag with a pore size of 1000d and immersed in a phosphate buffered saline solution (PBS, 100mL, pH 7.4). After incubation in a water bath for a predetermined time, 1mL of the aqueous supernatant was taken out, and the concentration of the fragrance in the release solution (i.e., the aqueous supernatant) was detected using an ultraviolet spectrophotometer and the release rate was calculated. Figure 6 As shown, under neutral environment, Eug / Cur-Zn Ⅱ @HA was able to sustainably release curcumin and eugenol up to 72 h, with a release rate of up to 80%, which demonstrated the pH dual-drug controlled release effect of the aromatic soluble polymer microneedles.

[0054] Application Example 2

[0055] This application example applies the aromatic soluble polymer microneedle prepared in Example 1 to the in vivo hygroscopic effect. Take a piece of aromatic soluble polymer microneedle material Eug / Cur-Zn Ⅱ @HA was applied to the depilated pig skin and removed at 0, 1, 2, 5, 8, and 10 seconds. Its dissolution was observed under a microscope, and photos of the pig skin after the microneedle was removed were taken. Figure 7 As shown, the aromatic soluble polymer microneedle material can effectively pierce pig skin and leave needle hole marks. Figure 8 The side microscope images of the aromatic soluble polymer microneedles taken from pig skin at different times from 0 to 10 s. It can be seen that the aromatic soluble polymer quickly dissolved in a short time, proving that the aromatic soluble polymer microneedle material Eug / Cur-Zn Ⅱ @HA's hygroscopic and dissolving effect in vivo.

[0056] Application Example 3

[0057] In this application example, the aromatic soluble polymer microneedles prepared in Example 1 were used to detect the free radical scavenging effect. A 0.2 mM 1,1-diphenyl-2-trinitrophenylhydrazine (DPPH) solution was prepared, and 1.5 mL of DPPH solution was mixed with ethanol in a ratio of 1:1 as a stock solution. The stock solution was mixed with Eug / Cur-Zn Ⅱ Mix the HA solution, incubate in dark for 1 hour, transfer to a cuvette, measure the absorbance at 517 nm and calculate the clearance rate. Fig. 9 As shown, with the increase of sample concentration, its scavenging rate at 517nm continued to rise, and finally reached a peak value, and the scavenging rate tended to be stable, indicating that the prepared aromatic soluble polymer microneedle material has good antioxidant properties.

[0058] Application Example 4

[0059] In this application example, the aromatic soluble polymer microneedles prepared in Example 1 were used to detect the free radical scavenging effect. A 7mM solution of 2,2-azino-bis(3-ethyl-benzothiazole-6-sulfonic acid) diammonium salt (ABTS) and a 2.45mM solution of potassium persulfate (K2S2O8) were prepared, and a phosphate buffer solution (PBS, 10mM, pH=7.4) was prepared. The ABTS solution and the K2S2O8 solution were mixed and placed in the dark for 24 hours as a stock solution; the stock solution was mixed with Eug / Cur-Zn Ⅱ @HA solution was mixed, incubated in dark for a certain period of time, and then transferred to a cuvette, and its absorbance was measured at 734nm and the clearance rate was calculated. Fig.10 As shown, with the increase of sample concentration, the clearance rate at 734nm continued to rise and finally reached a peak value, and the clearance rate tended to be stable, indicating that the prepared aromatic soluble polymer microneedle material has good antioxidant properties.

[0060] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A method for preparing an aromatic soluble polymer microneedle, characterized in that: The following steps are involved: S1, first dissolving eugenol and curcumin in ethanol respectively to obtain a eugenol ethanol solution and a curcumin ethanol solution, and then mixing the eugenol ethanol solution and the curcumin ethanol solution to obtain a eugenol-curcumin ethanol mixed solution; S2, first dissolving zinc acetate hexahydrate in deionized water to obtain a zinc acetate hexahydrate aqueous solution, and then adding the zinc acetate hexahydrate solution and Tris buffer in sequence to the eugenol-curcumin ethanol mixed solution obtained in S1 while stirring, and then obtaining self-assembled carrier-free nanoparticles containing eugenol and curcumin; S3. Dissolve the self-assembled carrier-free nanoparticles containing eugenol and curcumin obtained in S2 in a soluble polymer solution, pour the solution into a polytetrafluoroethylene microneedle mold after stirring at room temperature, and demold the solution after drying to obtain aromatic soluble polymer microneedles.

2. The method for preparing a fragrance soluble polymer microneedle according to claim 1, characterized in that: In S1, the concentration of the curcumin ethanol solution is 5 mg / mL, and the concentration of the eugenol ethanol solution is 4 mg / mL.

3. The method for preparing a fragrance soluble polymer microneedle according to claim 1, characterized in that: In S2, the concentration of zinc acetate hexahydrate is 0.2 mM.

4. The method for preparing a fragrance soluble polymer microneedle according to claim 1, characterized in that: In S2, the pH value of the Tris buffer is 8.0; The Tris buffer solution is prepared by dissolving tris(hydroxymethyl)aminomethane in deionized water, adjusting the pH to 8.0 with hydrochloric acid, and then adding deionized water to make the volume of the buffer solution 1 L to obtain the Tris buffer solution.

5. The method for preparing a fragrance soluble polymer microneedle according to claim 1, characterized in that: In S3, the soluble polymer solution is a hyaluronic acid solution; The preparation method of the hyaluronic acid solution is: dissolving hyaluronic acid in deionized water, then centrifuging the solution to defoam, and waiting for the solution to become clear and transparent to obtain a soluble hyaluronic acid solution.

6. The method for preparing a fragrance-soluble polymer microneedle according to claim 5, characterized in that: The mass ratio of the hyaluronic acid to deionized water is 1:

4.

7. A fragrance-soluble polymer microneedle prepared by the method according to any one of claims 1 to 6, characterized in that: The polymer microneedle comprises a load and a wrapping layer, wherein the load is self-assembled carrier-free nanoparticles containing eugenol and curcumin, and the wrapping layer is a soluble hyaluronic acid microneedle.

8. The aromatic soluble polymer microneedle according to claim 7, characterized in that: The structure of the self-assembled carrier-free nanoparticles containing eugenol and curcumin is eugenol-curcumin and Zn Ⅱ The coordination ball.

9. The aroma-soluble polymer microneedle according to claim 7, characterized in that: The average diameter of the self-assembled carrier-free nanoparticles containing eugenol and curcumin is 150 nm.

10. An application of the aromatic soluble polymer microneedle as claimed in claim 7, characterized in that: The aromatic soluble polymer microneedles are used for preparing sustained-release and anti-inflammatory materials.

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