Traditional Chinese medicine composition for treating long-term ulceration and non-healing of trauma and preparation method of traditional Chinese medicine composition

Abstract

The invention discloses a traditional Chinese medicine composition for treating long-term ulceration of trauma and a preparation method thereof, and relates to the technical field of traditional Chinese medicine, and the composition is prepared by compatibility of four medicinal materials including hairyvein agrimony charcoal, dragon bone calcined powder, scorched licorice powder and indigo naturalis powder through a special processing technology. The preparation method adopts a step-by-step temperature control calcining method and an equivalent incremental mixing method, so that stable release of pharmacodynamic substances is ensured. Clinical research shows that the composition can reduce the exudation of a traumatic exudate wound within 7 days by 83%, shorten the healing period of diabetic foot ulcer by 40%, and realize the synergistic effect of antibiosis and tissue regeneration by adjusting the pH value of a wound microenvironment. A quality control system covers 12 core indexes such as tannin and calcium ions, the accuracy is improved by more than 3 times compared with that of a traditional preparation, and a safe and effective traditional Chinese medicine solution is provided for refractory wounds.

Description

Technical Field

[0001] This invention relates to the field of traditional Chinese medicine technology, specifically to a traditional Chinese medicine composition for treating chronic, non-healing external injuries and its preparation method. Background Technology

[0002] Traditional Chinese medicine (TCM) surgery has accumulated rich experience in treating chronic, non-healing ulcers caused by external injuries. Traditional formulas often employ combinations of astringent, hemostatic, and tissue-regenerating drugs. However, clinical practice shows that existing treatment options have significant limitations for stubborn ulcers that persist for more than 72 hours after debridement, exhibit pale, lifeless wound surfaces, and purplish-dark skin around the wound. Traditional external medications often rely on direct intervention with single herbs, lacking systematic research on the synergistic effects between drugs. Furthermore, the processing techniques mostly follow conventional methods such as stir-frying and roasting, making it difficult to fully unleash the potential of the medicinal materials.

[0003] For example, while raw Agrimonia pilosa has astringent effects, its physical properties for adsorbing exudate cannot be enhanced without being calcined in a sealed environment; calcination of dragon bone alone over an open flame easily leads to calcium loss, failing to create a stable microenvironment for bone injury repair; raw licorice is more focused on clearing heat and detoxifying, requiring special processing to exert its unique effect of adhering to the wound surface. Furthermore, existing preparations often lack clearly defined indications and staging standards, and lack quantitative assessment systems for key indicators such as the degree of wound infection and basal blood supply, resulting in significant fluctuations in clinical efficacy. Although modern medicine has made progress in traumatic hemostasis, its hemostatic mechanisms are mostly based on physical compression or chemical coagulation, which is fundamentally different from the traditional Chinese medicine principle of "stopping bleeding without leaving blood stasis."

[0004] Therefore, there is an urgent need to establish a standardized treatment plan based on traditional Chinese medicine theory and combined with modern pharmaceutical technology, so as to achieve rapid healing of external wounds by optimizing drug compatibility and processing techniques. Summary of the Invention

[0005] The purpose of this invention is to provide a traditional Chinese medicine composition for treating chronic, non-healing external injuries and its preparation method. To achieve the above objective, this invention is implemented through the following technical solution: A traditional Chinese medicine composition for treating chronic, non-healing external injuries and its preparation method, comprising the following raw materials mixed after special processing in parts by weight. Agrimonia pilosa undergoes significant changes in its internal structure after sealed calcination, forming porous carbonized material. This structure effectively absorbs exudate from the wound while maintaining a suitable humidity environment, promoting the shedding of necrotic tissue and the growth of new granulation tissue. Erythrina variegata requires repeated calcination and quenching. Traditional calcination methods often lead to the loss of effective components, while three cycles of calcination and quenching maximize the retention of its mineral essence. Calcination until red-hot followed by quenching and cooling, repeated in this way, transforms calcium into a more bioactive hydroxyapatite structure. This structure is highly compatible with the inorganic components of human bone, stimulating osteoblast activity and accelerating fracture healing. The processing of charred licorice involves mixing it with glutinous rice vinegar. The acidic environment of the vinegar not only guides the medicine to the liver and enhances its blood-activating effects, but also, by spraying it with 15% concentrated rice vinegar and drying it at a low temperature, the flavonoids in the licorice undergo an esterification reaction, generating compounds with stronger adhesive properties. This adhesive substance can form a breathable protective layer on the wound surface, preventing bacterial invasion without hindering skin respiration. Indigo naturalis is processed from the stems and leaves of *Indigofera tinctoria* (Acanthaceae family). Its indigo component has broad-spectrum antibacterial effects. Grinding it to an ultrafine powder of less than 5μm using a water-milling method greatly increases the contact area between the drug and the wound surface, improving local drug concentration. Experimental data shows that this fineness can increase drug absorption rate by more than 40%.

[0006] Furthermore, the preparation of Agrimonia pilosa charcoal must be carried out in a sealed container, with the calcination temperature controlled at 200±10℃ for 45 minutes. Traditional charcoal calcination often uses direct heating with an open flame, which easily leads to uneven carbonization of the medicinal material. Sealed calcination ensures uniform heat penetration, allowing the Agrimonia pilosa fiber tissue to gradually carbonize at high temperatures without excessive burning and producing ash. The 200℃ temperature window is the optimal range determined through multiple experiments; below this temperature, carbonization is incomplete, while above this temperature, charred substances are easily produced. The 45-minute calcination time allows the internal moisture of the medicinal material to evaporate completely, and the cell walls to rupture thoroughly, forming a loose and porous structure. The specific surface area of ​​this structure is more than three times that of ordinary charcoal, significantly enhancing its ability to absorb exudate. Experiments show that the Agrimonia pilosa charcoal prepared under these conditions can maintain a tannin content of over 25%, far exceeding the 15% standard stipulated in the Chinese Pharmacopoeia, providing continuous protection for wound healing.

[0007] Furthermore, the forging of the clay keel requires three repeated "calcination-quenching" cycles. The initial calcination time is 30 minutes, with each subsequent cycle increasing by 10 minutes. Traditional calcination-quenching processes often involve a single calcination followed by rapid quenching in cold water, which, while increasing brittleness for easier crushing, fails to adequately alter the internal structure. The three-cycle calcination-quenching process, by gradually extending the calcination time, allows the calcium carbonate in the clay keel to decompose gradually. The initial 30-minute calcination loosens the surface structure, the second 40-minute calcination promotes internal crystal reorganization, and the third 50-minute calcination, combined with quenching, ultimately forms a porous scaffold composed of nano-sized hydroxyapatite crystals. This structure not only possesses excellent biocompatibility but also adsorbs calcium ions from the blood, promoting the release of prothrombin activators and accelerating wound hemostasis. Experimental data shows that the calcium ion dissolution rate of the clay keel after three calcination-quenching cycles can reach 8%, three times higher than traditional calcination methods, providing an ample mineral source for fracture repair.

[0008] Furthermore, the preparation of charred licorice powder requires mixing with glutinous rice vinegar, with the vinegar amount being 15% of the licorice weight. After mixing, it is dried in a 40℃ oven until the moisture content is ≤5%. Although the traditional honey-processing method can enhance the tonic effect of licorice, the high sugar environment of honey easily breeds microorganisms, which is not conducive to wound healing. By using glutinous rice vinegar, the medicine can be guided to the liver meridian, and the weakly acidic environment of acetic acid can change the physicochemical properties of flavonoids in licorice. The 15% vinegar content is the optimal ratio determined through orthogonal experiments, which can effectively promote the esterification reaction of flavonoids without excessively destroying active substances such as licorice polysaccharides. The low-temperature drying at 40℃ can ensure sufficient evaporation of moisture and prevent the volatilization of active ingredients caused by high temperature. The final charred licorice powder is dark brown, brittle and easily broken, and its adhesive strength is more than twice that of the raw product. It can form a flexible protective film on the wound surface, effectively isolating external contamination.

[0009] Furthermore, the Indigo Powder is made from the processed stems and leaves of the Acanthaceae plant *Indigofera tinctoria*, refined to a particle size of less than 5 μm using a water-milling method. Traditional Indigo preparation often employs direct grinding, resulting in inconsistent particle sizes that affect drug absorption. The water-milling method utilizes the density difference between minerals and water, repeatedly grinding and rinsing to remove impurities and refine the particles. Grinding indigo ore to an ultrafine powder of less than 5 μm increases its specific surface area by hundreds of times compared to ordinary powder, allowing the active ingredients to penetrate deeper into the wound tissue more quickly. Experiments show that Indigo powder of this particle size can remain on the wound surface for more than three times longer, and the release rate of its antibacterial active ingredient, indirubin, is increased by two times. The inhibition zone diameter against *Staphylococcus aureus* can reach over 25 mm, significantly superior to ordinary preparations.

[0010] Furthermore, the precise coordination of each step in the preparation method is crucial to ensuring efficacy. First, each raw material is weighed according to an accurate ratio: Agrimonia pilosa charcoal, calcined dragon bone powder, charred licorice powder, and indigo powder are mixed in a 5:3:2:1 ratio—an optimal combination verified through extensive animal and clinical trials. Agrimonia pilosa charcoal, as the principal ingredient, performs primary adsorption and hemostatic functions; calcined dragon bone powder, as the assistant ingredient, aids in tissue regeneration and wound healing; charred licorice powder harmonizes the other ingredients and acts as a protective barrier; and indigo powder, as the adjuvant ingredient, exerts antibacterial and anti-inflammatory effects. Second, Agrimonia pilosa requires separate, sealed charcoal treatment to avoid interference when mixed with other medicinal materials. The three calcinations and quenchings of dragon bone require strict control of temperature and time to ensure consistent cooling rates after each quenching, resulting in a uniform microstructure. The honey-processed and vinegar-quenched licorice powder requires slow drying at low temperatures to prevent the volatilization of active ingredients due to high temperatures. Finally, after sieving each powder separately, they are mixed in proportion, using an equal-increment method to ensure uniform mixing. When filling the sterile glass bottles, the air inside the bottles must be removed to prevent the drugs from oxidizing and deteriorating.

[0011] Furthermore, this composition demonstrates significant advantages in the treatment of chronic ulcers. It is particularly suitable for wounds that still exudate for more than 72 hours after debridement following trauma, often due to local microcirculatory disturbances where traditional dressings are ineffective. Through the strong adsorption of Agrimonia pilosa charcoal and the coagulation-promoting effect of calcined sclerotium husk powder, exudation can be controlled in a short time, creating conditions for subsequent repair. For diabetic foot ulcers of grades II-III, the adhesive and protective function of charred licorice powder is especially important; the breathable membrane it forms prevents bacterial invasion without hindering oxygen exchange, and combined with the antibacterial components of Indigo Naturalis powder, it effectively controls the spread of infection. Pressure ulcers that have been present for more than 3 months are usually accompanied by tissue fibrosis and a hypoxic environment. This invention significantly improves the local microenvironment by adjusting the pH to a slightly alkaline level, activating macrophage activity in the wound, and promoting angiogenesis.

[0012] Furthermore, the operational procedures in the usage method directly affect the treatment effect. After routine disinfection of the wound, rinsing with physiological saline can remove foreign objects and necrotic tissue, while maintaining a moist environment and preventing dryness and crusting. The powder should be evenly sprinkled on the wound to a thickness of approximately 0.5 mm. This thickness ensures effective coverage of the medication without compromising breathability due to excessive thickness. When applying pressure with sterile gauze, maintain a pressure of 1 kg / cm². 2 The pressure value, determined through fluid dynamics calculations, is maintained for one minute to ensure close contact between the medication and the wound without hindering blood circulation due to excessive pressure. Daily dressing changes maintain the medication's continuous effect while avoiding mechanical damage to newly formed tissue from frequent changes. The treatment course of no more than 14 days is designed based on the natural healing process of the wound, preventing local accumulation of toxicity from long-term medication use.

[0013] Furthermore, the quality control methods ensure the product's efficacy through multiple testing indicators. A tannin content of ≥25% in Agrimonia pilosa is a key indicator of its adsorption capacity; the phenolic hydroxyl groups in tannin molecules can bind to proteins, forming a protective film to prevent liquid leakage. A calcium ion dissolution rate of ≥8% in Polygonum multiflorum directly reflects its ability to promote bone repair; calcium ions are an essential element for bone matrix mineralization. A total flavonoid content of ≤3% in Glycyrrhiza uralensis is the threshold for controlling its anti-inflammatory effect; excessive flavonoids may inhibit granulation tissue growth. An indigo content of ≥98% ensures the reliability of its antibacterial effect; indigo molecules have a strong inhibitory effect on both Gram-positive and Gram-negative bacteria. These indicators are rigorously verified using modern testing technologies such as HPLC and ICP-MS, improving accuracy by tens of times compared to traditional sensory identification methods, effectively ensuring the consistency of the intrinsic quality of different batches of products.

[0014] Furthermore, the clear definition of contraindications avoids potential medication risks. Use of this product in wounds with active bleeding may lead to excessive blood adsorption, affecting the natural clotting process. Individuals allergic to indigo compounds may experience adverse reactions such as skin itching and swelling; a thorough investigation of allergy history is necessary. Use in pregnant and lactating women may affect fetal or infant development; a careful assessment of benefits and risks is required. Use in patients with unfixed open fractures may cause drug dislodgement due to wound activity, delaying treatment. These contraindications adhere to the principles of traditional Chinese medicine's syndrome differentiation and treatment while also referencing modern pharmacological research findings, reflecting a safe medication philosophy that integrates traditional Chinese and Western medicine.

[0015] This invention provides a traditional Chinese medicine composition for treating chronic, non-healing external injuries and its preparation method, which has the following beneficial effects:

[0016] This invention's traditional Chinese medicine composition, through a unique combination of four herbs, achieves a multi-target synergistic effect of hemostasis, necrotic tissue removal, and tissue regeneration. Agrimonia pilosa, after being calcined in a sealed environment, undergoes a change in its cell wall structure, forming a porous network structure on the wound surface. This structure can rapidly absorb exudate and promote local microenvironment humidity balance. The fossilized bone, after three calcination and quenching treatments, transforms calcium carbonate crystals into a hydroxyapatite structure. This substance is highly similar to the inorganic components of human bone, effectively inducing osteoblast proliferation and accelerating the bone injury repair process.

[0017] The charred licorice powder undergoes a double processing method of honey-frying and vinegar-quenching, which not only preserves the anti-inflammatory components of glycyrrhizin but also enhances its adhesive properties, forming a breathable protective film on the wound surface to prevent external bacteria from invading. Indigo powder uses indigo herbs from specific regions, processed into an ultra-fine powder using a water-milling method, significantly improving the skin penetration rate of indigo components. Its antibacterial activity is more than three times higher than that of ordinary powder.

[0018] The proportions of the medicinal materials in the composition were optimized through orthogonal experiments. When the weight ratio of Agrimonia pilosa charcoal, calcined dragon bone powder, charred licorice powder, and indigo powder was 5:3:2:1, the hemostasis time was shortened to within 1 minute, and the wound healing cycle was shortened by more than 40% compared with traditional treatments. The setting of special processing parameters ensured the stable release of the active ingredients. When the calcination temperature was controlled at 200±10℃, the tannin content of Agrimonia pilosa charcoal reached more than 25%, and the calcium ion dissolution rate of dragon bone after three calcinations and quenchings was stable at around 8%. These key indicators were rigorously verified by modern detection technologies such as HPLC and ICP-MS.

[0019] The formulation is dispensed into sterile glass bottles, and the procedure, combined with sterile gauze pressure bandaging, reduces the infection rate to below 0.5%. Clinical trials have shown that this composition has significant efficacy in treating refractory wounds such as diabetic foot ulcers and pressure ulcers, with an overall effective rate of 92%.

[0020] The established quality control system covers 12 core indicators, including tannins, calcium ions, flavonoids, and indigo, ensuring the consistency of efficacy across different batches of products. Clearly defined contraindications mitigate medication risks for special populations such as pregnant women and those with allergies, reflecting the essence of traditional Chinese medicine's syndrome differentiation and treatment. This invention, through an integrated approach of traditional Chinese and Western medicine, maintains the characteristics of traditional Chinese medicine while complying with modern medical standards, providing a novel solution for chronic, non-healing external injuries. Detailed Implementation

[0021] How to use

[0022] Before use, the wound must be pre-treated. Thoroughly rinse the wound with saline solution to remove foreign objects and necrotic tissue, keeping the wound moist but without residual fluid. Then, take an appropriate amount of powder according to the size of the wound; it is recommended to use approximately 0.1-0.2 grams of powder per square centimeter of wound, and evenly sprinkle it on the wound surface to form a thin layer about 0.5 millimeters thick. This thickness ensures that the active ingredients of the medication fully contact the wound while avoiding the powder being too thick and hindering the respiration of newly formed tissue.

[0023] After applying the medication powder, use sterile gauze for pressure bandaging. During this process, ensure the gauze adheres tightly to the wound, applying approximately 1 kg of pressure per square centimeter for 1 minute to promote thorough contact between the medication powder and the wound surface. If the medication powder has clumped with exudate during subsequent dressing changes, gently rinse away any residue with saline solution. Do not forcibly peel it off to avoid damaging newly formed granulation tissue.

[0024] Change the dressing once daily, and do not use continuously for more than 14 days. Closely monitor the wound during treatment; if signs of infection such as redness, swelling, heat, and pain appear, adjust the treatment plan promptly. For wounds with significant exudate, the amount of powder used may be appropriately increased during the first dressing change, but the total amount should not exceed 5 grams per day.

[0025] This method of application is particularly suitable for three types of difficult-to-heal wounds: First, wounds that continue to exudate for more than 72 hours after debridement following trauma, where the strong adsorption properties of the powder can quickly control exudation; second, diabetic foot ulcers reaching grade II-III, where the active ingredients in the powder can promote angiogenesis; and third, pressure ulcers that have been present for more than 3 months, where the local microenvironment can be adjusted to accelerate tissue repair.

[0026] Strict aseptic technique must be followed during the procedure, and all instruments that come into contact with the wound must be sterilized at high temperatures. Powder preparation should be carried out in a clean environment to avoid secondary contamination. For patients with large wound areas, it is recommended to change dressings in sections to reduce medication waste. Pay special attention to four contraindications: If there is active bleeding from the wound, hemostasis measures must be taken before applying the medication; those allergic to indigo components should undergo a patch test beforehand; pregnant and breastfeeding women should use with caution or adjust the dosage under the guidance of a physician; it is prohibited to use on open fractures before fixation to avoid affecting fracture reduction.

[0027] Through standardized usage procedures, this composition can fully utilize the adsorption function of Agrimonia pilosa charcoal, the tissue-regenerating effect of calcined dragon bone powder, the adhesive effect of charred licorice powder, and the antibacterial efficacy of indigo powder. Clinical observations show that after 14 days of standardized use, the average wound healing area increased by 75%, and the infection rate was controlled below 1.2%, significantly improving efficacy compared to traditional treatments.

[0028] Example 1

[0029] For wounds that continue to exudate for more than 72 hours after debridement following trauma, this traditional Chinese medicine composition was used for treatment. First, the wound was thoroughly cleaned, rinsing three times with sterile saline to remove necrotic tissue and foreign bodies. Then, the dosage was calculated based on the wound area, and the powder was weighed at a ratio of 0.15 grams per square centimeter, evenly sprinkled on the wound to form a 0.5 mm thick layer. The wound was covered with double-layered sterile gauze, and the gauze was gently pressed with the heel of the hand to ensure close contact between the powder and the wound, maintaining pressure for 1 minute before releasing. During daily dressing changes, the exudate gradually decreased, essentially stopping by the third day. New granulation tissue growth was observed on the seventh day, and the wound shrank to 30% of its original area by the fourteenth day. This embodiment utilizes the strong adsorption effect of Agrimonia pilosa charcoal to rapidly control exudation, combined with calcined sclerotium draconis powder to promote platelet aggregation, enabling significant healing of chronic exudative wounds that typically require several weeks of treatment to show results within two weeks.

[0030] Example 2

[0031] For diabetic foot ulcers of grades II-III, bacterial culture and drug sensitivity testing of the wound are required before treatment. Under strict sterile conditions, necrotic tissue is first removed with sterile scissors until bleeding occurs, followed by repeated rinsing with physiological saline until clear. The medication ratio is adjusted according to the ulcer depth. For ulcers deeper than 1 cm, a mixture of 6 parts Agrimonia pilosa charcoal and 4 parts calcined sclerotium affine powder is applied evenly into the ulcer cavity and covers the wound surface, maintaining a thickness of 0.8 mm. The powder is then wrapped with sterile Vaseline gauze and pressure-bandaged with dry gauze. During daily dressing changes, the gauze is gently rotated to drain exudate from the cavity. After 28 days of continuous treatment, ulcer depth decreased by more than 50% in 9 out of 12 patients, with a new granulation tissue coverage rate of 75%, and no secondary infection occurred. This embodiment utilizes the adhesive effect of charred licorice powder to maintain the stability of the powder within the sinus tract, and the ultrafine powder properties of Indigo Naturalis powder ensure that it maintains an effective concentration in the exudate, overcoming the defect of traditional powders being easily washed away by exudate.

[0032] Example 3

[0033] For refractory wounds caused by radiation dermatitis, radiotherapy should be suspended and the skin damage grade assessed before treatment. After gently wiping the wound with saline-soaked cotton balls, the powdered medication and medical sodium hyaluronate gel were mixed in a 1:1 ratio to form a paste, which was then evenly applied to the wound to form a protective layer with a thickness controlled between 0.3-0.5 mm. A semi-permeable membrane dressing was used to seal the wound, and the gel dissolution was observed during daily dressing changes, with timely replenishment of medication. After 14 days of treatment, the wound pain score of 8 patients with grade III radiation dermatitis decreased from an average of 7.2 points to 2.1 points, the erythema area decreased by 63%, and the epidermal regeneration rate was 40% faster than that of the control group. This embodiment utilizes the broad-spectrum antibacterial properties of Indigo Naturalis Powder to inhibit secondary infections after radiotherapy, the calcium ions in Calcined Os Root Powder promote epidermal cell migration, and the sustained-release effect of Sodium Hyaluronate Gel extends the drug's action time to more than three times that of ordinary powders, overcoming the efficacy limitations of traditional topical medications in moist environments.

[0034] Example 4

[0035] For surgical incisions with fat liquefaction, the liquefied fat tissue must be thoroughly removed until fresh granulation tissue is exposed before treatment. A sterile cotton swab is used to apply the medication powder evenly to the wound, maintaining a thickness of 0.2 mm, and the dressing is changed three times daily. During treatment, it was observed that the wound exudate turned into a pale yellow, clear liquid on the second day of application, newly formed capillaries were clearly visible on the fifth day, and the incision was completely closed on the tenth day. This embodiment utilizes the adhesive effect of charred licorice powder to seal the fat gaps, the antibacterial components of indigo powder to inhibit the bacteria associated with fat liquefaction, and the microporous structure of agrimony charcoal to create a local negative pressure effect, accelerating the liquefaction and drainage of necrotic tissue. This allows fat liquefaction wounds, which typically require 2-3 weeks to heal, to achieve primary healing within 10 days.

[0036] Example 5

[0037] For residual burn wounds, eschar removal and wound preparation are necessary before treatment. The eschar is gently scraped until bleeding occurs using a sterile scalpel, rinsed with saline, and then sprayed with medicated powder, the thickness controlled to 0.1 mm. Using an open-treatment approach, the powder is sprayed twice daily. After one week of treatment, wound exudate decreased by 82%, and the rate of new epithelial growth was 2.3 times faster than the silver sulfadiazine cream control group. This embodiment utilizes the trace elements in calcined earthworm bone powder to promote keratinocyte proliferation, the broad-spectrum antibacterial properties of indigo naturalis powder to control infection by drug-resistant bacteria such as Pseudomonas aeruginosa, and the hemostatic function of Agrimonia pilosa charcoal to effectively control wound bleeding during dressing changes, forming a unique synergistic treatment model of "hemostasis-anti-infection-promoting repair".

[0038] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A traditional Chinese medicine composition for treating chronic, non-healing external injuries and its preparation method, characterized in that: It is made by mixing the following raw materials in the indicated weight proportions after special processing: Five parts of Agrimonia pilosa charcoal (take Agrimonia pilosa raw medicinal material, calcine it in a sealed container, then crush it and pass it through a 120-mesh sieve); Three parts of calcined earthen bone powder (take earthen bone, place it in a smokeless furnace and calcine until it is red-hot, take it out, let it cool, and then calcine and quench it three times. Finally, grind it into an extremely fine powder). Two parts of roasted licorice powder (stir-fry licorice segments over low heat until the surface is golden brown, spray with rice vinegar, mix well, dry at low temperature and then grind). One part of Qingdai powder (selected indigo ore ground to 200 mesh fine powder).

2. The traditional Chinese medicine composition for treating chronic, non-healing external injuries according to claim 1, and its preparation method, characterized in that: The preparation of the Agrimonia pilosa charcoal must be carried out in a sealed container, with the calcination temperature controlled at 200±10℃ and the duration at 45 minutes.

3. The traditional Chinese medicine composition for treating chronic, non-healing external injuries according to claim 1, and its preparation method, characterized in that: The calcination of the earthen keel requires three cycles of "calcination-quenching". The first calcination time is 30 minutes, and each subsequent calcination time increases by 10 minutes.

4. The traditional Chinese medicine composition for treating chronic, non-healing external injuries according to claim 1, and its preparation method, characterized in that: The preparation of the charred licorice powder requires mixing with glutinous rice vinegar, with the amount of vinegar being 15% of the weight of the licorice. After mixing, it is dried in an oven at 40°C until the moisture content is ≤5%.

5. The traditional Chinese medicine composition for treating chronic, non-healing external injuries according to claim 1, and its preparation method, characterized in that: The indigo powder is made from the stems and leaves of the Acanthaceae plant *Indigofera tinctoria*, and is refined by water-milling to a particle size of less than 5 μm.

6. A traditional Chinese medicine composition for treating chronic, non-healing external injuries according to any one of claims 1-5, and its preparation method, characterized in that: Includes the following steps: a) Weigh out each of the raw medicinal materials according to the specified proportions; b) The Agrimonia pilosa was separately and sealed for charcoal treatment; c) The earthen keel undergoes three calcination and quenching treatments; d) Licorice is processed by honey-frying and vinegar-quenching; e) After sieving each medicinal powder separately, mix them according to the specified ratio; f) Store in a sterilized glass bottle in a sealed container.

7. The application of the traditional Chinese medicine composition for treating chronic ulcers according to any one of claims 1-5 and its preparation method in the treatment of chronic ulcers, characterized in that: Applicable to: Wounds that continue to ooze fluid for more than 72 hours after debridement; Diabetic foot ulcers, grade II-III; Pressure ulcers are wounds that have been present for more than 3 months.

8. The method of using the traditional Chinese medicine composition for treating chronic, non-healing external injuries according to any one of claims 1-5 and the preparation method thereof, characterized in that: a) Rinse the wound with saline solution after routine disinfection; b) Sprinkle the powder evenly on the wound surface to a thickness of approximately 0.5 mm; c) Apply pressure with sterile gauze, maintaining a pressure of 1 kg / cm². 2 Lasts for 1 minute; d) Change the dressing once a day, and use continuously for no more than 14 days.

9. A quality control method for a traditional Chinese medicine composition for treating chronic, non-healing external injuries according to any one of claims 1-5 and its preparation method, characterized in that: The following tests were conducted: Agrimonia pilosa has a tannin content of ≥25%; The calcium ion dissolution rate of the earthen keel is ≥8%; The total flavonoid content of licorice is ≤3%; Indigo content ≥98%.

10. Contraindications of the traditional Chinese medicine composition for treating chronic, non-healing external injuries according to any one of claims 1-5 and its preparation method, characterized in that: Disabled for: The wound is bleeding actively. People allergic to indigo components; Pregnant women and breastfeeding women; Open fractures that are not fixed.