Externally applied complexing agent as well as preparation method and application thereof

Abstract

The invention discloses an externally-applied complexing agent and a preparation method and application thereof.The externally-applied complexing agent comprises mesenchymal stem cell exosomes, a traditional Chinese medicine composition and a carrier, the traditional Chinese medicine composition comprises ligusticum wallichii, radix sophorae flavescentis, bletilla striata, centella asiatica, angelica sinensis and liquorice, and the externally-applied complexing agent is applied to foot rhagadia wounds. The staying time and concentration of the medicine at the rhagadia part can be maintained, the effective components are ensured and absorbed, the acting time of the medicine at the rhagadia part is prolonged, and the bioavailability is increased, so that the expected curative effect is obtained.

Description

Technical Field

[0001] The present invention relates to the technical field of skin medicines, in particular to an external application composite agent, a preparation method and an application thereof. Background Art

[0002] Cracked feet refer to linear cracks formed by the infiltration and hypertrophy of the foot skin due to various reasons, which loses its elasticity. This leads to dry skin on the heels, sides of the feet, soles of the feet, and between the toes. Cracks of varying lengths and depths are often seen in cold and dry seasons, and are common on the heels and outer edges of the feet. In mild cases, there is only dryness, thickening of the keratin, and cracking; in severe cases, the cracks are deep into the dermis, are prone to bleeding, and are painful. Cracked feet are mainly caused by skin diseases, but can also be caused by other non-disease factors. The main causes of cracked feet include foot trauma, physiological aging, certain skin diseases, dry environment, and physical and chemical factors.

[0003] Traditional topical skin drug formulations have shortcomings such as short retention time, high dosing frequency and poor patient compliance. The drug is retained on the skin surface for a short time, which affects the therapeutic effect. Multiple doses of the drug are required daily, and patient compliance with the drug is poor. Intervention measures for foot cracks cannot effectively improve patients' symptoms. Summary of the invention

[0004] To this end, the technical problem to be solved by the present invention is to provide an external application composite agent, which is low in cost, easy to absorb, and has the effects of treating chapped feet, promoting blood circulation and relieving pain, reducing swelling and promoting tissue regeneration, and softening and repairing the stratum corneum.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] An external application composite comprises mesenchymal stem cell exosomes, a traditional Chinese medicine composition and a carrier. The traditional Chinese medicine composition comprises chuanxiong, sophora flavescens, bletilla striata, centella asiatica, angelica sinensis and liquorice.

[0007] Furthermore, the mesenchymal stem cell exosomes and the traditional Chinese medicine composition are mixed and loaded into a carrier. In the external application composite, the mesenchymal stem cell exosomes are 10-15 mL, the traditional Chinese medicine composition is 15-20 mL, and the carrier is 65-75 mL.

[0008] Furthermore, the mesenchymal stem cell exosomes are human umbilical cord mesenchymal stem cell exosomes, and the carrier is Soluplus.

[0009] Furthermore, in the traditional Chinese medicine composition, chuanxiong is 3-8g, sophora flavescens is 10-12g, bletilla striata is 10-12g, centella asiatica is 8-10g, angelica is 7-9g, and liquorice is 10-15g.

[0010] A method for preparing an external application composite, the external application composite comprising mesenchymal stem cell exosomes, a traditional Chinese medicine composition and a carrier, the traditional Chinese medicine composition comprising chuanxiong, sophora flavescens, bletilla striata, centella asiatica, angelica sinensis and liquorice, the preparation of the external application composite comprising the following steps:

[0011] S1. Preparation of mesenchymal stem cell exosomes, cutting the umbilical cord into several tissue blocks and adding digestive enzymes for digestion, adding the digested tissue blocks to cell culture medium for culture to obtain crude exosome extracts, purifying the crude exosome extracts and collecting them to obtain umbilical cord mesenchymal stem cell exosomes;

[0012] S2, preparation of a Chinese medicine composition, mixing chuanxiong, sophora flavescens, bletilla striata, centella asiatica, angelica sinensis and liquorice uniformly and then dissolving them by ultrasonication to prepare a Chinese medicine composition;

[0013] S3, dissolving the umbilical cord mesenchymal stem cell exosomes of S1 and the traditional Chinese medicine composition of S2 by ultrasonication to obtain composite micelles;

[0014] S4. Preparation of the external application compound: adding the compound micelles into the carrier and stirring to dissolve them to form a mixed solution, and then sterilizing and packaging to obtain the external application compound.

[0015] Furthermore, in step S2, the specific process of preparing the Chinese medicine composition is as follows:

[0016] A1. Mix licorice with ultrapure water at a ratio of 1:5 (w / v), perform water bath sonication for 30 minutes, stir in a water bath at 60°C for 30 minutes, filter out the residue with a double-layer filter cloth after the sample is dried to room temperature, centrifuge the filtrate at 4000 rpm for 15 minutes, add 1.5 times the volume of acetone to the supernatant and shake well, let stand at -20°C for 30 minutes, finally, centrifuge the sample at 4000 rpm for 30 minutes at 4°C, discard the supernatant, evaporate the acetone, and freeze-dry to obtain licorice crude protein;

[0017] A2. Dissolve the licorice protein obtained in step (1) in ultrapure water to obtain a protein solution, add a mixed solution of Chuanxiong, Sophora flavescens, Bletilla striata, Centella asiatica and Angelica sinensis dissolved in methanol to the protein solution, sonicate 10 times with an ultrasonic disruptor at 60% power, remove methanol by rotary evaporation, and then sonicate in a water bath, centrifuge at 13000 rpm for 30 min, discard the supernatant, collect the precipitate, and obtain a Chinese medicine composition.

[0018] Furthermore, in step S3, the preparation process of the composite micelle is as follows:

[0019] B1. Place the Chinese medicine composition, umbilical cord mesenchymal stem cell exosomes and soluplus in a small beaker, add 15 mL of anhydrous ethanol, and sonicate to dissolve them completely to obtain an oil phase;

[0020] B2. Weigh mPEG chitosan and 0.1% (w / v) Gelucire 44 / 14 into a small beaker, add 20 mL of ultrapure water, and sonicate to dissolve them completely to obtain an aqueous phase;

[0021] B3, slowly adding the water phase drop by drop into the oil phase, stirring while dropping, and stirring in a 50°C water bath until the organic solvent evaporates, to obtain a traditional Chinese medicine multi-component nano-micelle colostrum;

[0022] B4. Cool the colostrum to room temperature and then perform ultrasonic dispersion. Filter with a 0.45 μm microporous filter membrane to obtain composite micelles.

[0023] An application of an external application compound in treating chapped foot wounds, the external application compound comprising mesenchymal stem cell exosomes, a traditional Chinese medicine composition and a carrier, wherein the traditional Chinese medicine composition comprises chuanxiong, sophora flavescens, bletilla striata, centella asiatica, angelica sinensis and liquorice.

[0024] The technical solution of the present invention achieves the following beneficial technical effects:

[0025] The topical composite preparation of the present invention can maintain the residence time and concentration of the drug at the chapped part through the low immunogenicity and repair effect of exosomes, ensure the absorption of effective ingredients, prolong the action time of the drug at the chapped part, and increase the bioavailability, so as to obtain the expected therapeutic effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the particle size distribution structure of an external application composite agent, a preparation method and an application thereof of the present invention;

[0027] Figure 2 It is a schematic diagram of infrared spectrum of an external application composite agent, a preparation method and an application thereof of the present invention;

[0028] A is a physical mixture of the components of the composite, B is chitosan-modified nanomicelles, C is blank nanomicelles, D is nanomicelles without chitosan modification, and E is a control of traditional Chinese medicine components. DETAILED DESCRIPTION

[0029] Example 1

[0030] An external application composite comprises mesenchymal stem cell exosomes, a traditional Chinese medicine composition and a carrier, wherein the mesenchymal stem cell exosomes are human umbilical cord mesenchymal stem cell exosomes, the traditional Chinese medicine composition comprises chuanxiong, sophora flavescens, bletilla striata, centella asiatica, angelica sinensis and liquorice, and the carrier is soluplus, which is a graft copolymer composed of polyvinyl caprolactam, polyvinyl acetate and polyethylene glycol, has a low CMC value and is easier to form micelles.

[0031] Mesenchymal stem cells are a type of pluripotent stem cells with high self-renewal ability and multidirectional differentiation potential. Their histological origin is the early developmental mesoderm. Mesenchymal stem cells are found in various tissues throughout the body. Umbilical cord mesenchymal stem cells have many advantages over mesenchymal stem cells derived from bone marrow, fat and other tissues. First, the cost of umbilical cord is low and there is no ethical controversy about its source; second, the acquisition of umbilical cord is non-traumatic and will not affect human health; third, umbilical cord mesenchymal stem cells have also been shown to have immunomodulation, low immunogenicity, paracrine, migration and genetic stability.

[0032] Exosomes have low immunogenicity and can effectively promote the repair of chapped feet and the matrix layer, inhibit inflammation and improve epithelial recovery. Chinese herbal mixture has the effects of promoting blood circulation, removing blood stasis, reducing swelling and relieving pain. Applying the compound to the wound can prolong its stay in the chapped area for a long time, ensuring that the effective ingredients therein are absorbed and maintain a certain concentration in the corresponding area, which can prolong the action time of the drug in the chapped area and increase bioavailability to obtain the expected therapeutic effect.

[0033] The chuanxiongzine in Chuanxiong has the effects of promoting blood circulation and removing blood stasis, resisting platelet aggregation, dilating arterioles, improving microcirculation, anti-oxidation, antagonizing calcium ions and anti-fibrosis. It can induce mesenchymal stem cells to differentiate into neuron-like cells and has an antioxidant effect; Sophora flavescens contains matrine, which has an inhibitory effect on a variety of skin fungi and Mycobacterium tuberculosis, and has a good moisturizing and spreading effect; Bletilla striata has the effects of astringent hemostasis, swelling reduction, muscle regeneration and skin moisturizing, and can be used for skin pruritus, chapped hands and feet, etc.; Centella asiatica glycoside in Centella asiatica has the effect of inhibiting abnormal collagen fiber proliferation, and has important functions such as promoting collagen synthesis and new blood vessel formation in the body, so it is beneficial to wound healing, affecting the ultrastructure of fibroblasts, promoting the proliferation of fibroblasts, and significantly increasing collagen and fibronectin; Angelica sinensis contains vegetable oil, which can moisturize and whiten the skin, increase the water content of skin cells, and soften the stratum corneum.

[0034] Traditional Chinese medicine is reconstructed to obtain nanoparticles, and exosomes are used to encapsulate the drugs. Exosomes not only change the physical and chemical properties of traditional Chinese medicine monomers, such as solubility and biological half-life, but also improve their targeting, and can be more efficiently absorbed by target cells. At the cellular level, nanoparticles can be quickly taken up by epithelial cells and macrophages, and the traditional Chinese medicine composition is delivered to the dermis in a targeted manner, while improving its stability and safety, increasing the amount of transdermal drug delivery, and promoting dermal retention of drugs.

[0035] Example 2

[0036] The vibration from ultrasound can temporarily increase the permeability of the exosome membrane, allowing drugs to enter the exosomes.

[0037] A method for preparing an external application composite, the external application composite comprising mesenchymal stem cell exosomes, a Chinese medicine composition and a carrier, wherein the mesenchymal stem cell exosomes are human umbilical cord mesenchymal stem cell exosomes, and the preparation thereof comprises the following steps:

[0038] S1. Preparation of mesenchymal stem cell exosomes, cutting the umbilical cord into several tissue blocks and adding digestive enzymes for digestion, adding the digested tissue blocks to cell culture medium for culture to obtain crude exosome extracts, purifying the crude exosome extracts and collecting them to obtain umbilical cord mesenchymal stem cell exosomes;

[0039] Specifically, the processing of umbilical cord mesenchymal stem cell exosomes includes the following process:

[0040] (1) Take a healthy fresh umbilical cord and rinse it with sterile saline for 3-4 times to clean it and remove any excess impurities. Then clean the umbilical cord with saline again;

[0041] (2) Soak the rinsed umbilical cord in iodine for 5 minutes to disinfect it, and then rinse the disinfected umbilical cord with sterile saline to remove the iodine;

[0042] (3) Place the cleaned umbilical cord in (2) into a sterile container and cut it into 1-3 cm tissue blocks with sterilized scissors. Rinse it repeatedly with sterile saline until there is no blood stain. If other impurities are found during the rinsing process, they should be discarded.

[0043] (4) Cut the tissue block in (3) into 1-3 mm thick pieces using sterile scissors. 2 For small tissue pieces, add mild digestive enzymes at a ratio of 0.25:1 between digestive enzyme and cell volume, place in a constant temperature shaker, and digest at 37°C for 30 minutes. Observe 3 times in the middle to avoid over-digestion of cells.

[0044] (5) After digestion, add cell culture medium, filter the digested mixture with a 100 μm sterile cell sieve, centrifuge, discard the supernatant, and collect the primary cells;

[0045] (6) Primary cells were cultured at 1.0×10 5 viable cells / cm 2 The cells were inoculated into sterile 175 culture flasks and placed at 37°C and 0.5% CO 2 Incubator, when the cells are cultured for 48 hours, the culture fluid is collected and centrifuged at 200,000 × g for 2 hours to obtain the crude exosome extract. The exosomes obtained in this step are not of high purity and are mixed with microvesicles and apoptotic bodies.

[0046] (7) Purification: Further purification is performed by sucrose gradient centrifugation. Different sucrose configurations are used to form a continuous system. The system is centrifuged at 200,000 × g for 14 h to allow the exosomes to settle to an isopycnic layer of 1.1 g / mL. The suspension in the density layer is collected to obtain the exosomes. The collected exosomes have a relatively high purity and are stored at 4°C for later use.

[0047] S2, preparation of a Chinese medicine composition, mixing chuanxiong, sophora flavescens, bletilla striata, centella asiatica, angelica sinensis and liquorice uniformly and then dissolving them by ultrasonication to prepare a Chinese medicine composition;

[0048] Specifically, the specific process of preparing the Chinese medicine composition is as follows:

[0049] A1. Weigh 5 g of Rhizoma Chuanxiong, 10 g of Radix Sophorae Flavescentis, 10 g of Rhizoma Bletillae, 8 g of Radix Centellae Asiatica, 7 g of Radix Angelicae Sinensis, and 10 g of Radix Glycyrrhizae, mix the Radix Glycyrrhizae with ultrapure water at a ratio of 1:5 (w / v), perform water bath sonication for 30 min, stir in a water bath at 60° C. for 30 min, filter out the residue with a double-layer filter cloth after the sample is dried to room temperature, centrifuge the filtrate at 4000 rpm for 15 min, add 1.5 times the volume of acetone to the supernatant and shake well, let stand at -20° C. for 30 min, finally, centrifuge the sample at 4000 rpm for 30 min at 4° C., discard the supernatant, evaporate the acetone, and freeze-dry to obtain the crude protein of Glycyrrhizae;

[0050] A2. Dissolve the licorice protein obtained in step (1) in ultrapure water (2 mg / mL) to obtain a protein solution, add a mixed solution of Chuanxiong, Sophora flavescens, Bletilla striata, Centella asiatica and Angelica sinensis dissolved in methanol to the protein solution, sonicate 10 times with an ultrasonic disruptor at 60% power, remove methanol by rotary evaporation and then sonicate in a water bath, centrifuge at 13000 rpm for 30 min, discard the supernatant, collect the precipitate, and obtain a Chinese medicine composition.

[0051] Using licorice protein to assemble and encapsulate other traditional Chinese medicines to obtain a traditional Chinese medicine composition with nanoparticles, combined with Figure 1 The particle size was measured by a particle size analyzer and the particle size was relatively uniform, with a PDI of 0.194±0.01. The Chinese medicine composition was stored in a refrigerator at 4°C and the particle size was measured for 7 consecutive days. The particle size fluctuated between 400-500nm, with a small range of variation, and the PDI values ​​were all less than 0.3, indicating that the assembled licorice protein drug-loaded nanoparticles had good stability. Figure 2 According to the HPLC infrared spectroscopy analysis, the Chinese medicine component control in spectrum E has an absorption peak, while the blank micelles, nano micelles and chitosan-modified nano micelles have no absorption peaks at the corresponding positions, and the infrared absorption spectra of the Chinese medicine composition and the blank carrier are basically the same, indicating that Chuanxiong, Sophora flavescens, Bletilla striata, Centella asiatica and Angelica sinensis are all encapsulated in the licorice protein nanoparticles, and the nanoparticles can be better absorbed by the body through the size effect and exert their effects.

[0052] S3, dissolving the umbilical cord mesenchymal stem cell exosomes of S1 and the traditional Chinese medicine composition of S2 by ultrasonication to obtain composite micelles;

[0053] Specifically, the preparation process of the composite micelle is as follows:

[0054] B1. Place the Chinese medicine composition, umbilical cord mesenchymal stem cell exosomes and soluplus in a small beaker according to the proportion, add 15 mL of anhydrous ethanol, and dissolve them completely by ultrasonication to obtain an oil phase;

[0055] B2. Weigh mPEG chitosan and 0.1% (w / v) Gelucire 44 / 14 into a small beaker, add 20 mL of ultrapure water, and sonicate to dissolve them completely to obtain an aqueous phase;

[0056] B3, slowly adding the water phase drop by drop into the oil phase, stirring while dropping, and stirring in a 50°C water bath until the organic solvent evaporates, to obtain a traditional Chinese medicine multi-component nano-micelle colostrum;

[0057] B4. After the colostrum is cooled and solidified to room temperature, it is dispersed ultrasonically (5 min, 5 s / 5 s). After filtering with a 0.45 μm microporous filter membrane, micelles of the composite agent are obtained.

[0058] Chitosan-modified nanoformulations can improve the stability and foot bioavailability of Chinese medicine compositions. Nanomicelles are nanocarriers for foot drug delivery. Nanomicelles also have certain advantages due to their large drug loading capacity, good stability and low irritation.

[0059] Example 3

[0060] Take the topical compound and conduct the following tests:

[0061] Comparison 1: 10 mL of mesenchymal stem cell exosomes, 15 mL of Chinese medicine mixture, and 75 mL of carrier to form 100 mL of topical composite;

[0062] Comparison 2: 15 mL of umbilical cord mesenchymal stem cell exosomes, 20 mL of Chinese medicine mixture, and 65 mL of carrier, forming 100 mL of external application compound;

[0063] Comparison 1 and comparison 2 were placed in a constant temperature and humidity incubator at 37±1°C and 75±5% relative humidity for 6 months. Samples were taken once in the first, second, third, and sixth months to observe the uniformity of stem cell exosomes. The results are as follows:

[0064] First month accelerated stability test results

[0065]

[0066]

[0067] Second month accelerated test results

[0068] plan Uniformity Mesenchymal stem cell exosomes: Chinese medicine composition: carrier Does it meet the requirements? Comparison 1 Uniform, no stratification 10:15:75 yes Comparison 2 Uniform, no stratification 15:20:65 yes

[0069] 3rd month accelerated test results

[0070] plan Uniformity Mesenchymal stem cell exosomes: Chinese medicine composition: carrier Does it meet the requirements? Comparison 1 Uniform, no stratification 10:15:75 yes Comparison 2 Uniform, no stratification 15:20:65 yes

[0071] Results of the 6th month accelerated test

[0072] plan Uniformity Mesenchymal stem cell exosomes: Chinese medicine composition: carrier Does it meet the requirements? Comparison 1 Uniform, no precipitation 10:15:75 yes Comparison 2 Uniform, no precipitation 15:20:65 yes

[0073] It can be seen from the test results shown above that with the increase of time, the composite agent has no stratification, its uniformity has not changed, and has good stability.

[0074] Example 4

[0075] Take the topical compound and conduct the following tests:

[0076] Comparison 1: 10 mL of umbilical cord mesenchymal stem cell exosomes, 15 mL of the traditional Chinese medicine composition, and the remaining 75 mL of the carrier are fully mixed to prepare an external application composite;

[0077] Comparison 2: 15 mL of umbilical cord mesenchymal stem cell exosomes, 20 mL of the traditional Chinese medicine composition, and the remaining 65 mL of the carrier, the above ingredients are fully mixed to prepare an external application composite;

[0078] The composites prepared from Comparison 1 and Comparison 2 and the vaseline foot crack ointment purchased on the market were randomly divided into three groups for a week of experiment. The test results are as follows:

[0079] Smear test

[0080]

[0081] From the above results, it can be seen that the effects of Comparison 1 and Comparison 2 are better than those of Vaseline foot chapped ointment, and most of them have no dryness, cracking, bleeding, desquamation, or pain.

[0082] Example 5

[0083] The topical compound, umbilical cord mesenchymal stem cell exosomes, Chinese medicine composition, and carrier were tested on 16 people for one week, and the test results are as follows:

[0084]

[0085]

[0086] The stem cell exosome complex can prolong the retention time of the drug in the cracked area, delay the effect of the drug in the eye tissue, achieve a sustained release effect, and significantly increase the content of the drug in the tissue of the cracked area, thereby improving the bioavailability of the drug, achieving the effects of improving the drug efficacy and avoiding drug loss.

[0087] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled 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 the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the claims of this patent application.

Claims

1. A composite for external application, characterized in that: The invention comprises mesenchymal stem cell exosomes, a traditional Chinese medicine composition and a carrier. The traditional Chinese medicine composition comprises chuanxiong, sophora flavescens, bletilla striata, centella asiatica, angelica sinensis and liquorice.

2. The external application composite according to claim 1, characterized in that The mesenchymal stem cell exosomes and the traditional Chinese medicine composition are mixed and loaded into a carrier. In the external application composite, the mesenchymal stem cell exosomes are 10-15 mL, the traditional Chinese medicine composition is 15-20 mL, and the carrier is 65-75 mL.

3. The external application composite according to claim 2, characterized in that The mesenchymal stem cell exosomes are human umbilical cord mesenchymal stem cell exosomes, and the carrier is Soluplus.

4. The external application composite according to claim 1, characterized in that In the traditional Chinese medicine composition, chuanxiong is 3-8g, sophora flavescens is 10-12g, bletilla striata is 10-12g, centella asiatica is 8-10g, angelica is 7-9g, and liquorice is 10-15g.

5. A method for preparing an external application composite, characterized in that: The topical composite comprises mesenchymal stem cell exosomes, a Chinese medicine composition and a carrier, wherein the Chinese medicine composition comprises chuanxiong, sophora flavescens, bletilla striata, centella asiatica, angelica sinensis and liquorice, and the preparation of the topical composite comprises the following steps: S1. Preparation of mesenchymal stem cell exosomes, cutting the umbilical cord into several tissue blocks and adding digestive enzymes for digestion, adding the digested tissue blocks to cell culture medium for culture to obtain crude exosome extracts, purifying the crude exosome extracts and collecting them to obtain umbilical cord mesenchymal stem cell exosomes; S2, preparation of a Chinese medicine composition, mixing chuanxiong, sophora flavescens, bletilla striata, centella asiatica, angelica sinensis and liquorice uniformly and then dissolving them by ultrasonication to prepare a Chinese medicine composition; S3, dissolving the umbilical cord mesenchymal stem cell exosomes of S1 and the traditional Chinese medicine composition of S2 by ultrasonication to obtain composite micelles; S4. Preparation of the external application compound: adding the compound micelles into the carrier and stirring to dissolve them to form a mixed solution, and then sterilizing and packaging to obtain the external application compound.

6. The preparation method according to claim 5, characterized in that: In step S2, the specific process of preparing the Chinese medicine composition is as follows: A1. Mix licorice with ultrapure water at a ratio of 1:5 (w / v), perform water bath sonication for 30 minutes, stir in a water bath at 60°C for 30 minutes, filter out the residue with a double-layer filter cloth after the sample is dried to room temperature, centrifuge the filtrate at 4000 rpm for 15 minutes, add 1.5 times the volume of acetone to the supernatant and shake well, let stand at -20°C for 30 minutes, finally, centrifuge the sample at 4000 rpm for 30 minutes at 4°C, discard the supernatant, evaporate the acetone, and freeze-dry to obtain licorice crude protein; A2. Dissolve the licorice protein obtained in step (1) in ultrapure water to obtain a protein solution, add a mixed solution of Chuanxiong, Sophora flavescens, Bletilla striata, Centella asiatica and Angelica sinensis dissolved in methanol to the protein solution, sonicate 10 times with an ultrasonic disruptor at 60% power, remove methanol by rotary evaporation, and then sonicate in a water bath, centrifuge at 13000 rpm for 30 min, discard the supernatant, collect the precipitate, and obtain a Chinese medicine composition.

7. The preparation method according to claim 6, characterized in that: In step S3, the preparation process of the composite micelle is as follows: B1. Place the Chinese medicine composition, umbilical cord mesenchymal stem cell exosomes and soluplus in a small beaker, add 15 mL of anhydrous ethanol, and sonicate to dissolve them completely to obtain an oil phase; B2. Weigh mPEG chitosan and 0.1% (w / v) Gelucire 44 / 14 into a small beaker, add 20 mL of ultrapure water, and sonicate to dissolve them completely to obtain an aqueous phase; B3, slowly adding the water phase drop by drop into the oil phase, stirring while dropping, and stirring in a 50°C water bath until the organic solvent evaporates, to obtain a traditional Chinese medicine multi-component nano-micelle colostrum; B4. Cool the colostrum to room temperature and then perform ultrasonic dispersion. Filter with a 0.45 μm microporous filter membrane to obtain composite micelles.

8. Use of an external application compound for treating chapped feet, characterized in that: The external application compound comprises mesenchymal stem cell exosomes, a traditional Chinese medicine composition and a carrier. The traditional Chinese medicine composition comprises chuanxiong, sophora flavescens, bletilla striata, centella asiatica, angelica sinensis and liquorice.

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