CN111632075B - Exosome preparation for promoting skin wound healing and preparation method thereof - Google Patents

Abstract

The invention relates to an exosome preparation for promoting skin wound healing and a preparation method thereof, belonging to the technical field of stem cells. An exosome preparation for promoting skin wound healing comprises the following components in parts by mass: 30-50 parts of a dry cell exosome extract, 10-20 parts of a basjoo flower extracting solution, 10-20 parts of a witch hazel extract and 10-20 parts of a chamomile extract. The preparation method is simple, and the raw materials are uniformly mixed according to the mass part ratio. According to the invention, the stem cell exosome and the components such as basjoo flower, chamomile, witch hazel, alginate are added, so that the wound surface hemostasis is accelerated, and the damaged tissue repair and skin regeneration are promoted; meanwhile, the product has the effects of resisting inflammation, inhibiting bacteria, relieving itching and moisturizing. Has the characteristics of good product effect, quick response, convenient use, no irritation to skin mucosa, safety, reliability and no scar.

Description

Exosome preparation for promoting skin wound healing and preparation method thereof

Technical Field

The invention belongs to the technical field of stem cells, and particularly relates to an exosome preparation for promoting skin wound healing and a preparation method thereof.

Background

Exosomes are vesicle produced by cells through a series of biological mechanisms such as endocytosis, fusion and efflux, and are excluded from the cells through active secretion, and are lipid bilayers in nature. The exosome contains miRNA and various molecular proteins and participates in regulating various physiological functions of cells. Exosomes can play a role in the treatment of various diseases by virtue of the therapeutic efficacy of carried biologically active substances such as proteins and mirnas with street stem cells. Research shows that the exosome has the effects of inhibiting inflammation, promoting skin cell proliferation and blood vessel regeneration and reducing myofibroblast accumulation, repairs injury through a paracrine mode, and provides a new method for treating skin injury.

Skin wounds are injuries encountered in daily life, particularly skin burns and scalds of varying degrees. The wound skin has slow healing process, is easy to cause infection if not treated properly, is easy to form scars, influences the appearance and brings great trouble to people. Most of the existing products for treating burns, scalds, traumas and the like only have the effects of easing pain and diminishing inflammation, the skin injury is healed slowly, and scars are easy to remain in the later period.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide an exosome preparation which does not leave scars, has the functions of resisting bacteria and diminishing inflammation and has quick response and promoting the healing of skin wounds and a preparation method thereof.

In order to achieve the purpose, the invention adopts the technical scheme that:

an exosome preparation for promoting skin wound healing comprises the following raw materials in parts by mass: 30-50 parts of a dry cell exosome extract, 10-20 parts of a basca flower extracting solution, 10-20 parts of a witch hazel extracting solution and 10-20 parts of a chamomile extracting solution.

In addition, the exosome in the exosome extract can promote the growth and migration of normal and wound fibroblasts, and acts on endothelial cells to induce the generation of blood vessels, and in addition, the exosome contains various regulatory signals, and after the signals are transmitted to the cells, the exosome can activate corresponding signal pathways (such as AKT, ERK1/2, STAT3 and the like), so that the expression of various nutritional factors (such as bFGF, IGF, VEGF and the like) is induced, and the repair of damaged tissues is promoted.

Contains various aromatic alcohol compounds, and has antiinflammatory, antibacterial, antipruritic, moisture keeping and antioxidant effects.

Preferably, the exosome preparation for healing the skin wound comprises the following raw materials in parts by mass: 40 parts of dry cell exosome extract, 15 parts of basjoo flower extract, 15 parts of witch hazel extract, 15 parts of chamomile extract, 0.5 part of allantoin and 0.05 part of alginate.

The exosome preparation with the optimal proportion has excellent wound repair effect while giving consideration to the effects of resisting inflammation, relieving itching and preserving moisture.

Preferably, the stem cell exosome extract comprises mesenchymal stem cell exosomes and mesenchymal stem cell culture supernatant.

Preferably, the preparation method of the stem cell exosome extract is characterized by comprising the following steps of:

(1) carrying out cell culture according to GMP to obtain mesenchymal stem cells;

(2) ultrasonically crushing the mesenchymal stem cells obtained in the step (1) to obtain mesenchymal stem cell exosomes;

(3) collecting the supernatant of the mesenchymal stem cells in the step (1) to obtain a supernatant exosome of the stem cell culture;

(4) and (3) respectively dissolving the mesenchymal stem cell exosomes obtained in the step (2) and the stem cell culture supernatant exosomes obtained in the step (3) in normal saline, and mixing and stirring uniformly in an equal volume to obtain a stem cell exosome extract.

Preferably, the exosome preparation for promoting skin wound healing further comprises the following components in parts by mass: 0.2-1 part of allantoin, 0.05-1 part of alginate, 1-5 parts of PEG-40 hydrogenated castor oil, 0.05-0.1 part of hyaluronic acid, 1-5 parts of butanediol, 0.1-0.3 part of methyl hydroxybenzoate, 0.1-1 part of hydroxyethyl cellulose, 0.05-0.1 part of EDTA-disodium and 4-33 parts of deionized water.

The alginate has the capacity of absorbing a large amount of liquid, can form a layer of stable sodium alginate reticular gel on the surface of a wound, and enables the wound surface to maintain a moist environment, thereby being beneficial to the healing of the wound and the regeneration of the skin, and accelerating the hemostasis of the wound surface; allantoin has the effects of promoting cell growth and accelerating wound healing, and is a good active agent component for treating skin injury.

Preferably, the exosome preparation for promoting skin wound healing further comprises the following components in parts by mass: 0.5 part of allantoin, 0.05 part of alginate, 5 parts of PEG-40 hydrogenated castor oil, 0.05 part of hyaluronic acid, 4 parts of butanediol, 0.1 part of methyl hydroxybenzoate, 0.5 part of hydroxyethyl cellulose, 0.05 part of EDTA-disodium and 4.75 parts of deionized water.

Preferably, the alginate is at least one of sodium alginate, potassium alginate, calcium alginate and ammonium alginate.

Preferably, the preparation method of the basjoo flower extracting solution comprises the following steps:

(1) taking fresh flowers of the ballflower, adding 18 times of 65% ethanol for the first time, and extracting for 1.5 hours; adding 10 times of 60% ethanol for the second time, and extracting for 1.5 hours; adding 8 times of 60% ethanol for the third time, and extracting for 1.5 hr; (2) filtering the extractive solutions extracted for 3 times with gauze, mixing filtrates, and concentrating the filtrate under reduced pressure to 5 times of the weight of flos Bombacis Cannabinae to obtain the extractive solution.

Preferably, the preparation method of the witch hazel extract comprises the following steps:

(1) taking fresh witch hazel, adding 18 times of 65% ethanol for the first time, and extracting for 1.5 hours; adding 10 times of 60% ethanol for the second time, and extracting for 1.5 hours; adding 8 times of 60% ethanol for the third time, and extracting for 1.5 hr; (2) filtering the extractive solutions extracted for 3 times with gauze, mixing filtrates, and concentrating the filtrate under reduced pressure to 5 times of the weight of flos Bombacis Cannabinae to obtain radix Hamamelis mollis extractive solution.

Preferably, the preparation method of the chamomile extracting solution comprises the following steps:

(1) taking fresh chamomile, adding 18 times of 65% ethanol for the first time, and extracting for 1.5 hours; adding 10 times of 60% ethanol for the second time, and extracting for 1.5 hours; adding 8 times of 60% ethanol for the third time, and extracting for 1.5 hr; (2) filtering the extractive solutions extracted for 3 times with gauze, mixing filtrates, and concentrating the filtrate under reduced pressure to 5 times of the weight of flos Bombacis Cannabinae to obtain flos Matricariae Chamomillae extractive solution.

The preparation method of the exosome preparation for promoting the skin wound healing specifically comprises the following steps:

s1 dissolving allantoin, alginate, hyaluronic acid and EDTA-disodium in deionized water, and stirring;

s2, adding butanediol, methyl hydroxybenzoate and hydroxyethyl cellulose into the solution obtained in the step S1 in proportion, and stirring and mixing uniformly;

s3, adding the basjoo flower extracting solution, the witch hazel extracting solution, the chamomile extracting solution and the PEG-40 hydrogenated castor oil into the solution obtained in the step S2, and stirring and mixing uniformly;

s4 adding the extract of the stem cell exosome into the solution obtained in the step S3, and stirring and mixing uniformly to obtain the finished product.

Compared with the prior art, the invention has the beneficial effects that:

(1) the exosome preparation for promoting the healing of the skin wound comprises a stem cell exosome extract which acts on subcutaneous fibroblasts, and focuses on the proliferation and repair of the fibroblasts and the improvement of the microenvironment of peripheral blood vessels; by adding natural plant components and nutrient substances such as the basjoo flower extract, the witch hazel extract and the like, the skin conditioning effects of resisting inflammation, inhibiting bacteria, preserving moisture, whitening and the like are achieved, so that the effect of promoting skin injury repair is achieved, the effect is quick, and no scar is left after the skin conditioning agent is used.

(2) All the raw materials used by the invention are food grade, and the invention does not contain antibiotics and hormones and does not generate toxic or side effect.

Drawings

Fig. 1 is a comparison of a day before and after 15 days of application of an exosome formulation of the present invention to damaged skin.

Detailed Description

To better illustrate the objects, aspects and advantages of the present invention, the present invention will be further described with reference to specific embodiments.

Example 1:

an exosome preparation for promoting skin wound healing comprises the following raw materials in parts by mass: 30 parts of dry cell exosome extract, 10 parts of basjoo flower extract, 10 parts of witch hazel extract, 10 parts of chamomile extract, 0.2 part of allantoin, 0.05 part of alginate, 5 parts of PEG-40 hydrogenated castor oil, 0.05 part of hyaluronic acid, 4 parts of butanediol, 0.1 part of methylparaben, 0.1 part of hydroxyethyl cellulose, 0.1 part of EDTA-disodium and 33 parts of deionized water.

The preparation method of the stem cell exosome extract comprises the following steps:

(1) culturing cells according to GMP, amplifying mesenchymal stem cells by using cell factory equipment, and harvesting to obtain 3 × 10 cells when the cell fusion rate reaches more than 95%⁸The mesenchymal stem cell of (a);

(2) ultrasonically crushing the mesenchymal stem cells obtained in the step (1) according to the proportion of 1 multiplied by 10⁸Adding the cell amount into 100ml of physiological saline, centrifuging for 10min at 4 ℃ under the condition of 300 Xg to remove cell debris, and collecting supernatant; centrifuging at 4 deg.C and 2500 Xg for 30min to remove apoptotic bodies, and collecting supernatant; then centrifugating for 1h at 4 ℃ under 13000 XgRemoving platelet impurities, and collecting supernatant; finally, centrifuging for 70min under the conditions of 4 ℃ and 100000 Xg to obtain the crushed mesenchymal stem cell exosome;

(3) centrifuging the mesenchymal stem cells in the step (1) for 10min at 4 ℃ under 2000 Xg conditions to remove cell debris, and collecting supernatant; centrifuging at 4 deg.C and 13000 Xg for 1 hr to remove platelet impurities, and collecting supernatant; finally centrifuging for 70min at 4 ℃ under 100000 Xg to obtain a stem cell culture supernatant;

(4) and (3) respectively dissolving the mesenchymal stem cell exosomes obtained in the step (2) and the stem cell culture supernatant exosomes obtained in the step (3) in normal saline, mixing and stirring uniformly in an equal volume, and enabling the concentration of a final protein solution to be 50mg/ml, so as to obtain a stem cell exosome extract.

The preparation method of the basjoo flower extracting solution comprises the following steps:

(1) taking fresh flowers of the ballflower, adding 18 times of 65% ethanol for the first time, and extracting for 1.5 hours; adding 10 times of 60% ethanol for the second time, and extracting for 1.5 hours; adding 8 times of 60% ethanol for the third time, and extracting for 1.5 hr; (2) filtering the extractive solutions extracted for 3 times with gauze, mixing filtrates, and concentrating the filtrate under reduced pressure to 5 times of the weight of flos Bombacis Cannabinae to obtain flos Bombacis Cannabinae extractive solution;

the preparation method of the witch hazel extract comprises the following steps:

(1) taking fresh witch hazel, adding 18 times of 65% ethanol for the first time, and extracting for 1.5 hours; adding 10 times of 60% ethanol for the second time, and extracting for 1.5 hours; adding 8 times of 60% ethanol for the third time, and extracting for 1.5 hr; (2) filtering the extractive solutions extracted for 3 times with gauze, mixing filtrates, and concentrating the filtrate under reduced pressure to 5 times of the weight of flos Bombacis Cannabinae to obtain radix Hamamelis mollis extractive solution;

the preparation method of the chamomile extracting solution comprises the following steps:

(1) taking fresh chamomile, adding 18 times of 65% ethanol for the first time, and extracting for 1.5 hours; adding 10 times of 60% ethanol for the second time, and extracting for 1.5 hours; adding 8 times of 60% ethanol for the third time, and extracting for 1.5 hr; (2) filtering the extractive solutions extracted for 3 times with gauze, mixing filtrates, and concentrating the filtrate under reduced pressure to 5 times of the weight of flos Bombacis Cannabinae to obtain flos Matricariae Chamomillae extractive solution.

The preparation method of the exosome preparation for promoting the healing of the skin wound comprises the following steps:

s1 dissolving allantoin, alginate, hyaluronic acid and EDTA-disodium in deionized water, and stirring;

s2, adding butanediol, methyl hydroxybenzoate and hydroxyethyl cellulose into the solution obtained in the step S1 in proportion, and stirring and mixing uniformly;

s3, adding the basjoo flower extracting solution, the witch hazel extracting solution, the chamomile extracting solution and the PEG-40 hydrogenated castor oil into the solution obtained in the step S2 according to a proportion, and stirring and mixing uniformly;

s4 adding the extract of the stem cell exosome into the solution obtained in the step S3 according to a certain proportion, and stirring and mixing uniformly to obtain a finished product.

Example 2:

an exosome preparation for promoting skin wound healing comprises the following raw materials in parts by mass: 30 parts of dry cell exosome extract, 20 parts of basjoo flower extract, 20 parts of witch hazel extract, 20 parts of chamomile extract, 0.3 part of allantoin, 0.08 part of alginate, 2 parts of PEG-40 hydrogenated castor oil, 0.08 part of hyaluronic acid, 1 part of butanediol, 0.1 part of methylparaben, 0.5 part of hydroxyethyl cellulose, 0.05 part of EDTA-disodium and 4 parts of deionized water.

The extract of the exosome of the stem cell, the extract of basjoa flower, the extract of hamamelis virginiana and the extract of chamomile were prepared according to the preparation method in example 1.

The preparation method of the exosome preparation for promoting the healing of the skin wound comprises the following steps:

s1 dissolving allantoin, alginate, hyaluronic acid and EDTA-disodium in deionized water, and stirring;

s2, adding butanediol, methyl hydroxybenzoate and hydroxyethyl cellulose into the solution obtained in the step S1 in proportion, and stirring and mixing uniformly;

s3, adding the basjoo flower extracting solution, the witch hazel extracting solution, the chamomile extracting solution and the PEG-40 hydrogenated castor oil into the solution obtained in the step S2 according to a proportion, and stirring and mixing uniformly;

s4 adding the extract of the stem cell exosome into the solution obtained in the step S3 according to a certain proportion, and stirring and mixing uniformly to obtain a finished product.

Example 3:

an exosome preparation for promoting skin wound healing comprises the following raw materials in parts by mass: 50 parts of dry cell exosome extract, 10 parts of basjoo flower extract, 10 parts of witch hazel extract, 10 parts of chamomile extract, 1 part of allantoin, 1 part of alginate, 1 part of PEG-40 hydrogenated castor oil, 0.1 part of hyaluronic acid, 5 parts of butanediol, 0.3 part of methylparaben, 1 part of hydroxyethyl cellulose, 0.1 part of EDTA-disodium and 11 parts of deionized water.

The extract of the exosome of the stem cell, the extract of basjoa flower, the extract of hamamelis virginiana and the extract of chamomile were prepared according to the preparation method in example 1.

The preparation method of the exosome preparation for promoting the healing of the skin wound comprises the following steps:

s1 dissolving allantoin, alginate, hyaluronic acid and EDTA-disodium in deionized water, and stirring;

s2, adding butanediol, methyl hydroxybenzoate and hydroxyethyl cellulose into the solution obtained in the step S1 in proportion, and stirring and mixing uniformly;

s3, adding the basjoo flower extracting solution, the witch hazel extracting solution, the chamomile extracting solution and the PEG-40 hydrogenated castor oil into the solution obtained in the step S2 according to a proportion, and stirring and mixing uniformly;

s4 adding the extract of the stem cell exosome into the solution obtained in the step S3 according to a certain proportion, and stirring and mixing uniformly to obtain a finished product.

Experimental example 1: physical and chemical indexes

The characteristics are as follows: the product is a slightly yellowish, transparent, clear and thick emulsion.

And (3) quality detection: the product is randomly sampled and stored at the temperature of 4-25 ℃, and the sensory evaluation of color, clarity and smell is not obviously changed after 1, 3, 6, 9 and 12 months of storage respectively, which shows that the product is stable in property within 12 months after being unpacked and used.

Skin patch test detection: and (4) selecting qualified patch materials, and attaching the sample and the blank control group to the forearm curve of the subject for 24 hours. After removing the patch device, the interval is 30min, the skin reaction is observed after the indentation disappears, and the skin reaction is observed once again after 24h and 48h of the patch test respectively. The grading criteria for adverse skin reactions are shown in Table 1. The result of the patch test can show that the components in the product do not cause adverse reactions such as allergy.

TABLE 1 adverse skin reaction grading

Experimental example 2: test for healing Effect of skin injury

General data:

60 subjects using the preparation were observed between 1 month in 2019 and 12 months in 2019, and were randomly divided into 30 subjects (17 men and 13 women) in the test group and 30 subjects (15 men and 15 women) in the control group. The comparative difference of age, sex, burn and scald position, area and other data between two groups has no significance (P is more than 0.05).

The method comprises the following steps:

test groups: (1) debridement and wound surface cleaning: mixing the raw materials in a ratio of 1: the 2000 chlorhexidine solution is used for cleaning and removing wound foreign matter, if blister exists, the blister is firstly drained, and then the wound is flushed by 0.9% physiological saline. (2) The product can be applied directly to wound surface, and can be covered with sterile gauze and bandaged according to the size and position of wound surface, or directly exposed. It is administered in the morning and evening 2 times daily. Wound healing was observed on days 1, 3, 7 and 15, respectively (patients who were cured in the middle of the course could stop using the wound healing agent).

Control group: the debridement method is the same as above, and after drying, a proper amount of iodophor is directly applied to the wound surface, and sterile gauze can be covered on the wound surface according to the size and the position of the wound surface and the wound surface can be bound properly or directly exposed. Similarly, it is administered 2 times daily in the morning and evening. Wound healing was observed on days 1, 3, 7 and 15, respectively (patients who were cured in the middle of the course could stop using the wound healing agent).

Observation indexes are as follows:

(1) comprehensive judgment standard for burn and scald curative effect. And (3) healing: the burn and scald wound surface is completely or basically healed, and clinical symptoms completely disappear. The effect is shown: more than 90% of burn and scald wounds heal, and most clinical symptoms disappear. Effectively, the burn and scald wound surface is partially healed, and partial clinical symptoms are improved. And (4) invalidation: the burn and scald wound surface and clinical symptoms are not improved.

(2) Calculating the wound healing rate: the size of the wound surface is printed on a transparent film on days 1, 3, 7 and 15 respectively, the area of the wound surface is measured and calculated, and then the wound healing rate is calculated. Thereby objectively evaluating the effect. Wherein the formula is as follows: the wound healing rate is (original wound area-unhealed wound area)/original wound area.

(3) Wencouver scar scale (VSS) score: the method is mainly used for evaluating the hyperplastic scar of a patient, and comprises 4 dimensions of scar color, softness, vascularity and thickness, the total score is 15, and the score is higher when the scar is more serious.

The treatment data acquisition strictly follows the statistical principle and is analyzed and processed by software SPSS17.0, and P <0.05 indicates that the difference has statistical significance.

As a result:

1. comparison of the overall therapeutic effects of the two groups

TABLE 2 comparison of the overall efficacy of the two groups of subjects

The results in the table show that the total treatment significant efficiency of the test subjects is 93.34%, which is higher than that of the control patients, and the difference is statistically significant (P < 0.05).

2. Comparison of healing time between two groups

TABLE 3 comparison of recovery time of two groups of subjects

As can be seen from table 3, the test groups all significantly shortened the time required to heal the patients, and the differences were statistically significant compared to the control group: p < 0.05.

3. General observation of two groups of wound surfaces

TABLE 4 day 1, 3, 7, 15 healing status in two groups of subjects

4. Comparison of healing rates of two groups of wounds

TABLE 5 comparison of wound healing rates of two groups

	Test group	Control group
			Day 1	(3.28±2.77)％	0
Day 3	(33.75±1.51)％	(16.73±3.57)％
			Day 7	(70.86±2.62)％	(39.94±2.61)％
Day 15	(95.36±2.50)％	(52.63±3.61)％

The results in the table show that the differences of the wound healing rates of the test group and the control group at each time point are significant, and the differences between the time points are significant.

5. Two groups of wound healing scar formation rate scores

TABLE 6 comparison (score) of VSS scores after two groups of treatment

Group of	Number of examples	Color	Softness	Vascularity distribution	Thickness of
						Test group	30	1.42±0.18	1.38±0.16	1.64±0.18	1.50±0.17
Control group	30	1.85±0.21	2.25±0.24	2.01±0.25	1.92±0.22

After 15 days of treatment, the skin color, softness, vascularity and thickness score of the skin wound of the test subjects in the test group are all significantly lower than those of the control group, and the difference has statistical significance (P is less than 0.05).

6. Comparative example before and after wound surface after use

Fig. 1A shows the skin injury after scald, and fig. 1B shows the healing effect of the skin injury after 15 days of using the product of the invention. Therefore, the product of the invention has excellent skin healing effect, no scar and smooth surface.

In conclusion, the product has good healing treatment effect on the burn wound, feels mild, comfortable and not greasy when being used, and can show obvious treatment effect after 2 weeks.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the protection scope of the present invention, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims (5)

1. The exosome preparation for promoting the healing of skin wound surfaces is characterized by being prepared from the following raw materials in parts by mass: 30-50 parts of a dry cell exosome extract, 10-20 parts of a basca flower extracting solution, 10-20 parts of a witch hazel extracting solution, 10-20 parts of a chamomile extracting solution, 0.2-1 part of allantoin, 0.05-1 part of alginate, 1-5 parts of PEG-40 hydrogenated castor oil, 0.05-0.1 part of hyaluronic acid, 1-5 parts of butanediol, 0.1-0.3 part of methyl hydroxybenzoate, 0.1-1 part of hydroxyethyl cellulose, 0.05-0.1 part of EDTA-disodium and 4-33 parts of deionized water;

the stem cell exosome extract comprises mesenchymal stem cell exosomes and mesenchymal stem cell culture supernatant; the preparation method of the stem cell exosome extract comprises the following steps:

(1) carrying out cell culture according to GMP to obtain mesenchymal stem cells;

(2) ultrasonically crushing the mesenchymal stem cells obtained in the step (1) to obtain mesenchymal stem cell exosomes;

(3) collecting the supernatant of the mesenchymal stem cells in the step (1) to obtain a supernatant exosome of the stem cell culture;

(4) respectively dissolving the mesenchymal stem cell exosomes obtained in the step (2) and the stem cell culture supernatant exosomes obtained in the step (3) in normal saline, and mixing and stirring uniformly in equal volume to obtain a stem cell exosome extract;

the preparation method of the basjoo flower extracting solution comprises the following steps:

(1) taking fresh flowers of the ballflower, adding 18 times of 65% ethanol for the first time, and extracting for 1.5 hours; adding 10 times of 60% ethanol for the second time, and extracting for 1.5 hours; adding 8 times of 60% ethanol for the third time, and extracting for 1.5 hr; (2) filtering the extractive solutions extracted for 3 times with gauze, mixing filtrates, and concentrating the filtrate under reduced pressure to 5 times of the weight of flos Bombacis Cannabinae to obtain flos Bombacis Cannabinae extractive solution;

the preparation method of the witch hazel extract comprises the following steps:

(1) taking fresh witch hazel, adding 18 times of 65% ethanol for the first time, and extracting for 1.5 hours; adding 10 times of 60% ethanol for the second time, and extracting for 1.5 hours; adding 8 times of 60% ethanol for the third time, and extracting for 1.5 hr; (2) filtering the extractive solutions extracted for 3 times with gauze, mixing filtrates, and concentrating the filtrate under reduced pressure to 5 times of the weight of flos Bombacis Cannabinae to obtain radix Hamamelis mollis extractive solution;

the preparation method of the chamomile extracting solution comprises the following steps:

(1) taking fresh chamomile, adding 18 times of 65% ethanol for the first time, and extracting for 1.5 hours; adding 10 times of 60% ethanol for the second time, and extracting for 1.5 hours; adding 8 times of 60% ethanol for the third time, and extracting for 1.5 hr; (2) filtering the extractive solutions extracted for 3 times with gauze, mixing filtrates, and concentrating the filtrate under reduced pressure to 5 times of the weight of flos Bombacis Cannabinae to obtain flos Matricariae Chamomillae extractive solution;

the exosome preparation is applied to preparation of products for treating burns and scalds.

2. A preparation of exosomes for promoting healing of cutaneous wounds according to claim 1, characterised in that: 40 parts of dry cell exosome extract, 15 parts of basjoo flower extract, 15 parts of witch hazel extract and 15 parts of chamomile extract.

3. A preparation of exosomes for promoting healing of cutaneous wounds according to claim 1, characterised in that: 0.5 part of allantoin, 0.05 part of alginate, 5 parts of PEG-40 hydrogenated castor oil, 0.05 part of hyaluronic acid, 4 parts of butanediol, 0.1 part of methyl hydroxybenzoate, 0.5 part of hydroxyethyl cellulose, 0.05 part of EDTA-disodium and 4.75 parts of deionized water.

4. The exosome preparation for promoting skin wound healing according to claim 1, wherein the alginate is at least one of sodium alginate, potassium alginate, calcium alginate and ammonium alginate.

5. A method of preparing an exosome preparation for promoting skin wound healing according to any one of claims 1 to 4, characterised by comprising the steps of:

s1 dissolving allantoin, alginate, hyaluronic acid and EDTA-disodium in deionized water, and stirring;

s2, adding butanediol, methyl hydroxybenzoate and hydroxyethyl cellulose into the solution obtained in the step S1 in proportion, and stirring and mixing uniformly;

s3, adding the basjoo flower extracting solution, the witch hazel extracting solution, the chamomile extracting solution and the PEG-40 hydrogenated castor oil into the solution obtained in the step S2 according to a proportion, and stirring and mixing uniformly;

s4 adding the extract of the stem cell exosome into the solution obtained in the step S3 according to a certain proportion, and stirring and mixing uniformly to obtain a finished product.

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