Microarray needle-shaped liquid capsules and preparation and use thereof

Abstract

This invention relates to a microarray needle-like liquid capsule, its preparation, and its application, belonging to the field of biomedical materials technology. The microarray needle-like liquid capsule is composed of soluble microneedles and an encapsulating agent, possessing a hollow structure capable of loading chemotherapeutic drugs, particularly suitable for non-water-soluble drugs. This design effectively solves the problem of insufficient drug loading capacity in traditional microneedles and improves drug bioavailability by using ethanol as a solvent, while simultaneously achieving synergistic treatment of chemotherapy and local tumor ablation. This invention not only possesses excellent mechanical properties and biocompatibility but also demonstrates significant advantages in the treatment of melanoma, reducing skin inflammation and improving patient comfort.

Description

Technical Field

[0001] This invention belongs to the field of biomedical materials technology, specifically relating to a microarray needle-shaped liquid capsule and its preparation and application. Background Technology

[0002] The skin is the largest organ in the human body. Melanoma, due to its high metastatic potential and high mortality rate, has seen its global incidence and mortality rates rise year by year, becoming one of the deadliest skin diseases. Currently, common treatments for melanoma include chemotherapy and local ablation therapy. Chemotherapy is a treatment that uses chemical drugs to kill cancer cells, inhibit their growth and reproduction, and promote their differentiation; it is suitable for most cancer patients. However, when chemotherapy is used alone, the treatment effect may not be sufficient to achieve the expected clinical goals or outcomes. Commonly used chemotherapy drugs include paclitaxel, doxorubicin, and oxaliplatin. Because melanoma is sensitive to paclitaxel, it is often used as one of the main drugs for treating melanoma in clinical practice. Local ablation therapy is a non-invasive treatment method for treating local tumors. It uses physical or chemical methods to directly act on the lesion area, thereby ablating or destroying the diseased tissue. It has advantages such as being minimally invasive and having a short recovery period, but its treatment failure rate is relatively high. In recent years, a common local ablation therapy is percutaneous ethanol injection, which involves injecting anhydrous ethanol into the tumor site to cause cell dehydration and coagulative necrosis within the tumor, thereby killing cancer cells.

[0003] Currently, many drug delivery systems, such as microcapsules, injectable hydrogels, and transdermal patches, have been developed to address the question of how to deliver drugs to tumor sites. Among them, microneedle patches in transdermal patches can load drugs into the needle lumen and achieve on-demand administration with minimal invasiveness. Moreover, microneedle patches can effectively overcome the shortcomings of other local drug delivery systems, such as low drug penetration and high inflammatory response, balancing patient comfort and painlessness as much as possible. Patients can even administer the drugs themselves, providing a promising drug delivery strategy for the treatment of melanoma.

[0004] Many types of microneedle patches have been developed and manufactured for cancer treatment, including solid microneedles, coated microneedles, hydrogel microneedles, hollow microneedles, and soluble microneedles. Solid microneedles use metal or silicon microneedles to pierce the skin and create micron-sized channels through which drugs can be delivered directly to the skin layer. However, solid microneedles may leave metal fragments in the skin, causing erythema and swelling. Coated microneedles load drugs onto the outside of the microneedle tip, and the drugs are delivered rapidly after piercing the skin. However, a thin coating results in a low drug loading capacity, limiting the efficiency of drug delivery. Hydrogel microneedles are usually made of swollen polymers. When a hydrogel microneedle is inserted, the polymer swells upon entering the skin and releases the drug. However, the accuracy of drug delivery is limited. Hollow microneedles place the drug in an empty area, loading and delivering large doses of drug through the device. However, they require external devices for drug delivery. For drug delivery combined with microneedle patches, soluble microneedles are currently the most popular choice due to their lower manufacturing cost and the fact that they are made from materials with good solubility and biocompatibility. When soluble microneedles are inserted into the skin, the polymer dissolves in the tissue fluid, releasing the drug. However, soluble microneedles also have disadvantages such as poor mechanical properties and limited drug loading capacity.

[0005] Although many studies have used soluble microneedle patches to deliver drugs to cancer sites, the following limitations still exist:

[0006] (1) Soluble microneedles have a low drug loading capacity.

[0007] (2) There are still few reports on the differences in drug loading of soluble microneedles with different structures.

[0008] (3) Most studies usually use water as a solvent to dissolve chemotherapy drugs, but currently common chemotherapy drugs in clinical practice, such as paclitaxel, are difficult to dissolve in water due to their complex chemical structure, which limits their widespread clinical application to a certain extent.

[0009] (4) For chemotherapy drugs with poor water solubility, most studies use organic solvents such as dimethyl sulfoxide, N-methylpyrrolidone, and N,N-dimethylacetamide to dissolve them; or encapsulate the poorly water-soluble drugs with liposomes or micelles; or make them more soluble in water by chemically modifying the drug structure. However, there are few reports of using a solvent that can be absorbed by the human body, dissolve poorly water-soluble chemotherapy drugs, and treat melanoma at the same time. Summary of the Invention

[0010] In view of the above-mentioned shortcomings, the object of the present invention is to provide an application of a microarray needle-like liquid capsule for the treatment of melanoma after loading with drugs. The capsule consists of soluble microneedles and an encapsulating agent, and has a hollow structure capable of loading large doses of chemotherapy drugs.

[0011] Specifically, the microarray needle-shaped liquid capsule is equivalent to a portable container for loading drugs. Since the container contains no other substances, it can be completely filled with drugs, thus achieving high-dose drug delivery and overcoming the shortcoming of low drug loading capacity of soluble microneedles.

[0012] This invention also provides a method for preparing the microarray needle-shaped liquid capsule, specifically comprising the following steps:

[0013] Step 1: Preparation of soluble microneedles

[0014] 1-1: Preparation of a high-concentration sodium carboxymethyl cellulose solution;

[0015] 1-2: The high-concentration sodium carboxymethyl cellulose solution prepared in 1-1 is diluted to obtain a low-concentration sodium carboxymethyl cellulose solution;

[0016] 1-3: Drop a low-concentration sodium carboxymethyl cellulose solution into the microneedle mold and remove air bubbles from each needle cavity; then retain the low-concentration sodium carboxymethyl cellulose solution in the needle cavity and remove the low-concentration sodium carboxymethyl cellulose solution outside the needle cavity; next, drop a high-concentration sodium carboxymethyl cellulose solution into the microneedle mold and remove air bubbles from the needle cavity; finally, place the prepared microneedles to dry at room temperature.

[0017] 1-4: Take out the dried microneedles from 1-3. Sodium carboxymethyl cellulose forms the shell of the microneedles, and the inside of the microneedles is a hollow structure.

[0018] Further, in step 1, the concentration of the high-concentration sodium carboxymethyl cellulose solution is 0.001-0.03 g / mL, and the concentration of the low-concentration sodium carboxymethyl cellulose solution is 30%-70% of the concentration of the high-concentration sodium carboxymethyl cellulose solution; the methods for removing bubbles include vacuuming, ultrasonication, or centrifugation.

[0019] Step 2: Preparation of encapsulant

[0020] 2-1. Preparation of polydopamine (PDA) nanoparticle dispersion: Ammonia, deionized water, and anhydrous ethanol were mixed and stirred until a homogeneous mixed solution 1 was obtained; then, dopamine hydrochloride was dissolved in deionized water to obtain a dopamine hydrochloride solution; next, the dopamine hydrochloride solution was added to mixed solution 1 and stirred until a homogeneous solution was formed to obtain mixed solution 2; mixed solution 2 was centrifuged and the lower precipitate was collected to obtain crude PDA nanoparticles; the crude PDA nanoparticles were washed with anhydrous ethanol and deionized water, and then freeze-dried to obtain PDA nanoparticles; the PDA nanoparticles were stored in a refrigerator at 4°C in the dark.

[0021] 2-2. Preparation of silver (Argentum, Ag) modified PDA nanoparticles: Silver nitrate was dissolved in deionized water to obtain a silver nitrate solution; ammonia was added dropwise to the silver nitrate solution and stirred until a clear solution was obtained; the PDA nanoparticle solution prepared in step 2-1 was added to the clear solution to obtain mixed solution 3; mixed solution 3 was stirred in the dark and centrifuged to obtain crude Ag-modified PDA (PDA@Ag) nanoparticles; the crude PDA@Ag nanoparticles were washed with anhydrous ethanol and deionized water, and then freeze-dried to obtain PDA@Ag nanoparticles; the PDA@Ag nanoparticles were stored at room temperature in the dark.

[0022] 2-3. Add chitosan and 2-acrylamido-2-methylpropanesulfonic acid to deionized water and stir until a homogeneous mixed solution 4 is formed; add acrylamide to mixed solution 4 and stir until a homogeneous and transparent solution is formed, to obtain mixed solution 5; add the PDA@Ag nanoparticles prepared in step 2-2 to mixed solution 5 and stir until homogeneous, to obtain mixed solution 6; after stirring mixed solution 6 at room temperature until homogeneous, add crosslinking agent and initiator to mixed solution 6 and continue stirring at room temperature until homogeneous, to obtain mixed solution 7; finally, pour mixed solution 7 into a mold for polymerization to obtain the encapsulant.

[0023] Further, in step 2-1, the mass concentration of ammonia water is 25%-28%; the volume ratio of ammonia water:deionized water:anhydrous ethanol is 1:(40-50):(15-25); the concentration of dopamine hydrochloride solution is 45-55 mg / mL; the volume ratio of dopamine hydrochloride solution:ammonia water is (4.5-5.5):1; the centrifugation speed is 10000-12000 rpm, and the centrifugation time is 8-10 min.

[0024] Furthermore, in step 2-2, the mass concentration of ammonia is 25%-28%, the concentration of silver nitrate solution is 30-35 mg / mL, the concentration of PDA nanoparticles is 8-12 mg / mL, the mass ratio of silver nitrate to PDA nanoparticles is (160-170):1, and the centrifugation speed is 10000-12000 rpm.

[0025] Further, in steps 2-3, the mass ratio of chitosan:acrylamide:2-acrylamido-2-methylpropanesulfonic acid:deionized water:PDA@Ag nanoparticles is (0.25-0.35):1:(3.5-4.5):(14-16):(0.01-0.02), and the stirring temperature is 45-55℃; the crosslinking agent is N,N'-methylenebisacrylamide, and the initiator is potassium persulfate, with the mass ratio of crosslinking agent:initiator = 1:(45-55), and the stirring temperature is 55-65℃.

[0026] Step 3: Assembly of microarray needle-shaped liquid capsules

[0027] Chemotherapy drugs are dripped into the soluble microneedles prepared in step 1. After removing air bubbles, the encapsulating agent prepared in step 2 is attached to the microneedles to obtain microarray needle-shaped liquid capsules.

[0028] Furthermore, the chemotherapy drug is paclitaxel;

[0029] Furthermore, paclitaxel is added in the form of an ethanol solution of paclitaxel, with a solution concentration of 2-7 mg / mL.

[0030] The microarray needle-shaped liquid capsules prepared according to the steps described in this invention possess excellent mechanical properties, sufficient for skin penetration, and exhibit minimal inflammatory response after penetration, without affecting hair growth. However, when the same dose of drug is administered via injection to treat melanoma, it produces significant irritation, resulting in hair regrowth failure, indicating a strong skin inflammatory response. Therefore, the microarray needle-shaped liquid capsules can efficiently deliver large doses of drug, which has a significant advantage in the treatment of melanoma.

[0031] The present invention has the following beneficial effects:

[0032] 1. The microarray needle-shaped liquid capsules prepared in this invention not only possess sufficient mechanical properties to penetrate the skin, but also outperform most existing soluble microneedles. When the microarray needle-shaped liquid capsules are inserted into the melanoma site in mice, the microneedles dissolve due to their soluble properties, allowing for more rapid drug release within the animal's body. Their hollow structure enables high-dose drug loading, overcoming the shortcomings of current soluble microneedles, such as poor mechanical properties and limited drug loading capacity. Simultaneously, this invention also explores the differences in drug loading capacity between different microneedle structures (such as pyramidal and conical microneedle patches).

[0033] 2. The drug selected in this invention is paclitaxel. Due to its complex chemical structure and poor water solubility, paclitaxel has low bioavailability, which limits its widespread clinical application. Because of its extremely poor water solubility, researchers typically encapsulate paclitaxel for application. Meanwhile, paclitaxel can be completely dissolved in ethanol, dimethyl sulfoxide, N-methylpyrrolidone, and N,N-dimethylacetamide by vortexing for 3-5 minutes to form a homogeneous and stable drug solution.

[0034] 3. This invention utilizes ethanol, a component of alcoholic beverages, to dissolve paclitaxel in ethanol, thus addressing the issue of poor bioavailability of water-soluble chemotherapy drugs. Many people drink alcohol in daily life, indicating that ethanol is a solvent that the human body can use in appropriate amounts. Furthermore, research has shown that ethanol can induce cell dehydration and coagulative necrosis within tumors, thereby killing cancer cells and achieving local tumor ablation. Therefore, this invention abandons water as a solvent and chooses ethanol as the solvent. Ethanol not only increases the solubility of poorly water-soluble chemotherapy drugs, improving drug utilization and providing a novel application for these drugs, but also eliminates the need for near-infrared lasers, ultrasound, or other devices, enabling a strategy of synergistic treatment of melanoma through chemotherapy and percutaneous ethanol injection.

[0035] 4. The drugs that can be loaded in this invention are not only applicable to paclitaxel, but also to other drugs that are poorly soluble in water but soluble in ethanol.

[0036] 5. The chemotherapy drug loaded in this invention is an ethanol solution of paclitaxel. The strategy of using ethanol as a solvent provides a novel solution to the major problem of low bioavailability due to poor drug water solubility. Furthermore, ethanol as a solvent not only improves the solubility of poorly water-soluble drugs but also enables local tumor ablation, thus achieving synergistic treatment of chemotherapy and percutaneous ethanol injection in the simplest way, without the need for any devices. Compared to syringe injection in local drug delivery methods, the microarray needle-like liquid capsules prepared in this invention effectively reduce skin inflammation and demonstrate a new application for drug delivery in the treatment of melanoma.

[0037] 6. The microarray needle-shaped liquid capsules provided by the present invention have good biocompatibility, are harmless to animals or humans, and have the advantage of in vivo biodegradability. Attached Figure Description

[0038] Figure 1 The preparation process of the pyramid-shaped microneedles and the conical microneedles prepared in Example 1 is described.

[0039] Figure 2(a) is a bright-field image of the pyramid-shaped microneedle prepared in Example 1; (b) is a bright-field image of the conical microneedle prepared in Example 1; (c) is a super-resolution laser confocal microscopy image of the pyramid-shaped microneedle prepared in Example 1; and (d) is a super-resolution laser confocal microscopy image of the conical microneedle prepared in Example 1.

[0040] Figure 3 The volume of each pyramid-shaped and conical needle prepared for Example 1, and the volume of drug that the pyramid-shaped and conical microneedle patches can hold.

[0041] Figure 4The treatment effects of melanoma tumors in each group in Example 4 are shown.

[0042] Figure 5(a) shows a skin hair follicle image after injection treatment in Example 4; (b) shows a skin hair follicle image after treatment with microarray liquid capsules in Example 4. Detailed Implementation

[0043] It should be noted that the following embodiments will further explain the technical solution of the present invention, but these embodiments do not limit the scope of the present invention. Any modifications or equivalent substitutions to the technical solution of the present invention, as long as they do not depart from the basic spirit and scope of the present invention, should be included within the protection scope of the present invention. Devices not specifically indicated are all conventional devices in the art, and the technical means in the present invention are all conventional methods well known to those skilled in the art.

[0044] It should be noted that the method of the present invention is not limited to soluble materials such as sodium carboxymethyl cellulose; any soluble material can be used to prepare hollow microneedle patches.

[0045] Example 1: Preparation of soluble microneedles with hollow structure made of sodium carboxymethyl cellulose

[0046] Preparation method of soluble microneedles with hollow structure of sodium carboxymethyl cellulose, such as Figure 1 As shown.

[0047] Step 1: The specifications of the polydimethylsiloxane (PDMS) microneedle mold are pyramid and cone shapes with a height of 1.5 mm and a diameter of 0.66 mm.

[0048] Step 2: Dissolve each gram of sodium carboxymethyl cellulose in 33 mL of deionized water and stir thoroughly to obtain a high-concentration sodium carboxymethyl cellulose solution with a concentration of 0.03 g / mL.

[0049] Step 3: The high-concentration sodium carboxymethyl cellulose solution obtained in Step 2 is mixed with deionized water at a ratio of 3:7 (V / V) and stirred thoroughly to obtain a low-concentration sodium carboxymethyl cellulose solution.

[0050] Step four: First, drop about 1 mL of low-concentration sodium carboxymethyl cellulose solution into the pyramid and cone molds respectively, and use a vacuum operation to remove air bubbles from each needle cavity; then aspirate the low-concentration solution outside the needle cavity, drop about 1 mL of high-concentration sodium carboxymethyl cellulose solution into the mold, remove the air bubbles with a pipette, and then place the prepared microneedles to dry at room temperature.

[0051] Step 5: After about 48 hours, the dried pyramid and cone-shaped microneedles from Step 4 are removed. Sodium carboxymethyl cellulose forms the shell of the microneedles, which has a hollow internal structure.

[0052] Step six: In order to better observe the structure of the microneedle patch, sodium carboxymethyl cellulose was labeled with the fluorescent dye fluorescein isothiocyanate in step two.

[0053] The bright-field images of the obtained microneedle patches are shown in Figure 2(a) and Figure 2(b). It can be observed that both the pyramidal and conical microneedle patches have uniform and complete morphologies. As shown in Figure 2(c) and Figure 2(d), super-resolution laser confocal microscopy verified that both the pyramidal and conical microneedle patches have hollow internal structures.

[0054] After verifying the hollow structure of the microneedle patch, this invention explored the dosage of chemotherapy drugs that the microneedle patch can load. Theoretically, the drug loading capacity of the pyramidal and conical microneedles is calculated using their height and base diameter. The theoretical internal volume of each needle in the pyramidal and conical microneedle patches is 0.2178 mm². 3 With 0.1709mm 3 Regarding the actual dosage of the drug that can be loaded, such as... Figure 3 As shown, two types of hollow microneedles were filled using super-resolution laser confocal microscopy, and the hollow volume of an actual pyramid-shaped single microneedle was calculated to be 0.1558 mm². 3 The pyramid-shaped microneedle patch can hold 15.58 μL of drug, while the actual hollow volume of a single conical microneedle is 0.1074 mm. 3 The conical microneedle patch can hold 10.74 μL of drug. Compared to the theoretical volume of a single needle, the hollowness of the pyramidal hollow microneedle structure is 71.55%, and that of the conical hollow microneedle structure is 62.8%.

[0055] Example 2: Preparation of encapsulant

[0056] Step 1: Preparation of PDA nanoparticle dispersion: Mix 2 mL of (25%-28%) ammonia solution with 90 mL of deionized water and 40 mL of anhydrous ethanol, and stir at room temperature (25°C) for about 1 hour until homogeneous. Then, dissolve each gram of dopamine hydrochloride in 20 mL of deionized water and slowly pour it into the above mixed solution, stirring for about 24 hours to form a homogeneous and transparent mixed solution 1. Centrifuge mixed solution 1 at 10000-12000 rpm for 8-10 minutes and collect the lower precipitate to obtain crude PDA nanoparticles. Wash the crude PDA nanoparticles three times each with anhydrous ethanol and deionized water to obtain PDA nanoparticles. Finally, freeze-dry the prepared PDA nanoparticles and store them in a light-protected refrigerator at 4°C.

[0057] Step 2, Preparation of Ag-modified PDA nanoparticles (PDA@Ag): Dissolve 1 gram of silver nitrate in 30 mL of deionized water. Add 25%-28% ammonia solution dropwise to the above solution and stir until the brown precipitate disappears and the solution becomes clear again. Then add 0.3 mL of the 10 mg / mL PDA nanoparticle solution prepared in Step 1 to the clear solution to obtain mixed solution 2. Stir mixed solution 2 at 25°C in the dark for about 1 h, then centrifuge at 10000-12000 rpm for 8-10 min to obtain crude Ag-modified PDA (PDA@Ag) nanoparticles. Wash the crude PDA@Ag nanoparticles three times with anhydrous ethanol and three times with deionized water to obtain PDA@Ag nanoparticles. Finally, freeze-dry the prepared PDA@Ag nanoparticles and store them in the dark at room temperature.

[0058] Step 3, preparation of the encapsulant: Add 0.3g of chitosan and 1.0g of 2-acrylamido-2-methylpropanesulfonic acid to 15mL of deionized water and stir continuously at 45-55℃ for 4h until a homogeneous mixed solution 3 is formed. Add 4g of acrylamide to mixed solution 3 and stir until a homogeneous and transparent solution is formed, obtaining mixed solution 4. Add 0.015g of PDA@Ag nanoparticles prepared in step 2 to mixed solution 4 and stir at room temperature for about 10min to form a homogeneous mixed solution 5. Add 0.001g of crosslinking agent N,N'-methylenebisacrylamide and 0.05g of initiator potassium persulfate to mixed solution 5 and stir at room temperature for about 1min to obtain mixed solution 6. Finally, pour mixed solution 6 into a glass mold and polymerize at 55-65℃ for about 4h to obtain the encapsulant.

[0059] The encapsulant prepared in this invention is based on a solution of chitosan, 2-acrylamido-2-methylpropanesulfonic acid, and acrylamide, with the addition of PDA and Ag. PDA has attracted much attention due to its excellent adhesion, and doping the encapsulant with PDA can increase its adhesion; Ag is a good antibacterial agent, and the addition of Ag to the encapsulant can give it some antibacterial properties.

[0060] Example 3: Assembly of microarray needle-shaped liquid capsules

[0061] Step 1: The drug is dripped into the hollow soluble microneedles prepared in Example 1.

[0062] Step 2: Vacuum the vacuum to remove air bubbles.

[0063] Step 3: Apply the encapsulant prepared in Example 2 onto the soluble microneedles to obtain the microarray needle-shaped liquid capsules described in this invention.

[0064] It should be noted that paclitaxel is added in the form of an ethanol solution of paclitaxel, with a drug solution concentration of 5 mg / mL.

[0065] The purpose of this embodiment is to enable the assembled microarray needle-like liquid capsules to encapsulate paclitaxel and ethanol solutions within 7 days and ensure that they do not volatilize, thus allowing them to better penetrate into the tumor site in mice.

[0066] Example 4: Treatment of melanoma in mice

[0067] The experimental animals were 6-week-old female SPF-grade C57BL / 6 mice, belonging to an inbred strain commonly used in oncology, physiology, immunology, and genetics research. Their weight was 18-22g, and their certificate number was No. 110322231102976886. The laboratory temperature was 22±2℃, relative humidity 40%-60%, with ventilation fans. Five mice were housed in cages, with the cages cleaned and their food and drinking water changed every 3-4 days. After hair removal on the left abdomen, the mice were inoculated with 1×10⁻⁶ mice using a 1mL microsyringe. 6 Density of B16F10 (melanoma) cells. Tumor treatment was administered 3 days later, with each mouse receiving a paclitaxel / ethanol concentration of 5 mg / kg.

[0068] The control group in this experiment received no treatment outside the tumor. The treatment for melanoma was divided into six groups: G1: control group; G2: ethanol injection group; G3: ethanol-loaded microneedles group; G4: paclitaxel and aqueous solution injection group; G5: paclitaxel and ethanol solution injection group; and G6: paclitaxel and ethanol-loaded microneedles group.

[0069] Step 1: Insert microarray needle-shaped liquid capsules containing solvent ethanol (G3) or ethanol solution of the chemotherapy drug paclitaxel (G6) into the melanoma site of mice and hold for 5 minutes; the injection group received subcutaneous injection into the tumor (G2, G4, G5).

[0070] Step two: Nine days later, perform a second treatment with the same procedures as in step one.

[0071] Step 3: Weigh the mice every 2 days and measure the size of the tumor.

[0072] Table 1. Therapeutic effects of microneedles loaded with paclitaxel / ethanol on mouse melanoma.

[0073]

[0074] All experimental data were processed using GraphPadPrism software. The experimental results are shown in Table 1 and... Figure 4 .

[0075] Compared with the control group at the same time point: P < 0.05; n = 5

[0076] like Figure 4 Experimental results show that ethanol ablation therapy alone has a partial inhibitory effect on melanoma. When ethanol is used as a solvent to dissolve paclitaxel, an anticancer drug, it increases the solubility of paclitaxel and can also achieve synergistic treatment of melanoma with chemotherapy and local ablation, which has a significant inhibitory effect on melanoma.

[0077] Step four, furthermore, after 14 days of treatment, the tumor volume of all mice in the control group had reached the ethically prescribed upper limit (1500 mm). 3 Then, photographs were taken of each group of mice.

[0078] As shown in Figure 5, under the treatment effect of injection, no hair growth occurred at the treatment site in the group injected with paclitaxel and ethanol solution (G5 group) (Figure 5(a)), accompanied by an inflammatory response; while under the treatment effect of microarray needle-like liquid capsules, hair continued to grow at the treatment site in the group injected with paclitaxel and ethanol solution (G6 group) (Figure 5(b)). This indicates that the inflammatory response of melanoma treated with microarray needle-like liquid capsules is less than that of injection treatment.

Claims

1. A microarray needle-shaped liquid capsule, characterized in that, The microarray needle-shaped liquid capsule consists of soluble microneedles and an encapsulating agent. Sodium carboxymethyl cellulose is used to form the shell of the microneedles, which has a hollow structure and is used to load the chemotherapy drug paclitaxel. The paclitaxel is loaded in the form of an ethanol solution of paclitaxel with a solution concentration of 2-7 mg / mL. The microarray needle-shaped liquid capsule is used to prepare a drug for treating melanoma. The method for preparing the microarray needle-shaped liquid capsules includes the following steps: Step 1: Preparation of soluble microneedles 1-1. Prepare a high-concentration sodium carboxymethyl cellulose solution with a concentration of 0.001-0.03 g / mL; 1-2. Dilute the high-concentration sodium carboxymethyl cellulose solution prepared in 1-1 to obtain a low-concentration sodium carboxymethyl cellulose solution; the concentration of the low-concentration sodium carboxymethyl cellulose solution is 30%-70% of the concentration of the high-concentration sodium carboxymethyl cellulose solution. 1-3. Drop a low-concentration sodium carboxymethyl cellulose solution into the microneedle mold and remove air bubbles from each needle cavity; then retain the low-concentration sodium carboxymethyl cellulose solution in the needle cavity and remove the low-concentration sodium carboxymethyl cellulose solution outside the needle cavity; next, drop a high-concentration sodium carboxymethyl cellulose solution into the microneedle mold and remove air bubbles from the needle cavity; finally, place the prepared microneedles to dry at room temperature. 1-4. Take out the dried microneedles from 1-3. Sodium carboxymethyl cellulose forms the shell of the microneedles, and the inside of the microneedles is a hollow structure. Step 2: Preparation of encapsulant 2-1. Preparation of polydopamine nanoparticle dispersion: Ammonia, deionized water, and anhydrous ethanol were mixed and stirred until a homogeneous mixed solution 1 was obtained; then, dopamine hydrochloride was dissolved in deionized water to obtain a dopamine hydrochloride solution; next, the dopamine hydrochloride solution was added to mixed solution 1 and stirred until a homogeneous solution was formed to obtain mixed solution 2; mixed solution 2 was centrifuged and the lower precipitate was collected to obtain crude polydopamine nanoparticles; the crude polydopamine nanoparticles were washed with anhydrous ethanol and deionized water, and then freeze-dried to obtain polydopamine nanoparticles; the polydopamine nanoparticles were stored in a refrigerator at 4 ℃ in the dark. 2-2. Preparation of silver-modified polydopamine nanoparticles: Silver nitrate was dissolved in deionized water to obtain a silver nitrate solution; ammonia was added dropwise to the silver nitrate solution and stirred until a clear solution was obtained; the polydopamine nanoparticles prepared in step 2-1 were added to the clear solution to obtain mixed solution 3; mixed solution 3 was stirred in the dark and centrifuged to obtain crude silver-modified polydopamine nanoparticles; the crude silver-modified polydopamine nanoparticles were washed with anhydrous ethanol and deionized water, and then freeze-dried to obtain silver-modified polydopamine nanoparticles; the silver-modified polydopamine nanoparticles were stored at room temperature in the dark. 2-3. Add chitosan and 2-acrylamido-2-methylpropanesulfonic acid to deionized water and stir until a homogeneous solution is formed, to obtain mixed solution 4; add acrylamide to mixed solution 4 and stir until a homogeneous solution is formed, to obtain mixed solution 5; add the silver-modified polydopamine nanoparticles prepared in step 2-2 to mixed solution 5 and stir until a homogeneous solution is formed, to obtain mixed solution 6; stir mixed solution 6 at room temperature until homogeneous, then add crosslinking agent and initiator to mixed solution 6 and continue stirring at room temperature until a homogeneous solution is formed, to obtain mixed solution 7; finally, pour mixed solution 7 into a mold for polymerization to obtain an encapsulating agent; by mass ratio, chitosan: 2-acrylamido-2-methylpropanesulfonic acid: acrylamide: deionized water: silver-modified polydopamine nanoparticles = (0.25-0.35): 1: (3.5-4.5): (14-16): (0.01-0.02); Step 3: Preparation of microarray needle-shaped liquid capsules An ethanol solution of the chemotherapy drug paclitaxel is dropped into the hollow soluble microneedles prepared in step 1. After removing air bubbles, the encapsulating agent prepared in step 2 is attached to the microneedles to obtain microarray needle-shaped liquid capsules.

2. The microarray needle-shaped liquid capsule according to claim 1, characterized in that, In step 1, the methods for removing air bubbles include vacuuming, ultrasonication, or centrifugation.

3. The microarray needle-shaped liquid capsule according to claim 1, characterized in that, The ammonia solution in step 2-1 has a mass concentration of 25%-28%; the volume ratio of ammonia solution:deionized water:anhydrous ethanol is 1:(40-50):(15-25); the concentration of dopamine hydrochloride solution is 45-55 mg / mL; the volume ratio of dopamine hydrochloride solution:ammonia solution is (4.5-5.5):1; the centrifugation speed is 10000-12000 rpm, and the centrifugation time is 8-10 min.

4. The microarray needle-shaped liquid capsule according to claim 1, characterized in that, In step 2-2, the mass concentration of ammonia is 25%-28%, the concentration of silver nitrate solution is 30-35 mg / mL, the concentration of polydopamine nanoparticles is 8-12 mg / mL, the mass ratio of silver nitrate to polydopamine nanoparticles is (160-170):1, and the centrifugation speed is 10000-12000 rpm.

5. The microarray needle-shaped liquid capsule according to claim 1, characterized in that, In steps 2-3, the crosslinking agent is N,N'-methylenebisacrylamide, and the initiator is potassium persulfate. The mass ratio of crosslinking agent to initiator is 1:(45-55).

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