A long-acting targeted fullerol nasopharyngeal preparation, and a preparation method and application thereof

Abstract

The application discloses a long-acting targeted fullerol nasopharyngeal preparation and a preparation method and application thereof, and belongs to the technical field of nano drug delivery, wherein the active ingredient of the nasopharyngeal preparation comprises a three-layer core-shell structure nanoparticle, and the three-layer core-shell structure nanoparticle comprises, from inside to outside, a fullerol nanometer core, a polylactic acid-glycolic acid copolymer intermediate layer containing growth factors and a hyaluronic acid outer layer; the fullerol nanometer core refers to a nanometer-scale fullerol as a core. The application realizes synergistic delivery and differential release of the fullerol and the growth factors, the rapid release of the fullerol provides antioxidant protection, the slow release of the growth factors maintains repair signals, and the hyaluronic acid outer layer endows the nasal mucosa with targeted adhesion, thereby significantly prolonging the local drug efficacy maintenance time. The local residence half-life of the application is more than 6 hours, which is more than 3 times higher than that of a traditional hormone nasal spray, and an effective treatment concentration can be maintained by administering the preparation once or twice a day. In the treatment of nasopharyngeal radiation necrosis, the necrosis area can be reduced to 12%, and the vascular regeneration density is increased by more than 2 times.

Description

Technical Field

[0001] This invention belongs to the field of nanomedicine delivery technology, and more specifically, relates to a long-acting targeted fullerol nasopharyngeal preparation, its preparation method, and its application. Background Technology

[0002] Nasopharyngeal carcinoma has a high incidence rate in southern my country and Southeast Asia. Due to the deep location of the lesions and their proximity to the skull base and brainstem, radiotherapy is considered the preferred treatment for radical cure. However, while high-energy radiation kills tumor cells, it also damages local microvessels and matrix, triggering a burst of reactive oxygen species, ultimately leading to soft tissue necrosis in the nasal cavity, nasopharynx, oropharynx, and even hypopharynx. Literature reports that the necrosis rate after a single radiotherapy session can reach 3-5%, and can rise to over 40% after a second radiotherapy session. Lesions usually appear 6 months to several years after radiotherapy, and can progress to intractable ulcers, persistent infections, skull base osteonecrosis, and even rupture of major blood vessels, seriously endangering life.

[0003] Current clinical treatments mainly include a combination of methods such as nasal irrigation to remove necrotic tissue, antibiotics to control infection, nasal corticosteroid sprays to suppress inflammation, hyperbaric oxygen therapy to improve blood supply, and endoscopic debridement. However, the overall efficacy is limited, with a cure rate of only 13.4%-28.6%. Existing methods have the following shortcomings: short duration of drug efficacy; irrigation easily washes away new granulation tissue and is cumbersome; corticosteroid sprays can only suppress inflammation for a short period of 2-4 hours and long-term use may suppress mucosal immunity; hyperbaric oxygen therapy requires 20-40 treatment courses, is expensive, has poor compliance, and lacks comprehensive efficacy in terms of sustained antioxidant, angiogenesis, and matrix remodeling.

[0004] Fullerene-based carbon nanomaterials, due to their cage-like conjugated structure and excellent free radical scavenging ability, have always been a hot topic in radiation damage prevention and treatment research. However, existing fullerene preparations have the following shortcomings in the treatment of nasopharyngeal radiation necrosis: Fullerols reported in patent CN115463094B Montmorillonite ointment is primarily designed for external application to the gastrointestinal mucosa. Its particle size is in the hundreds of nanometers (200-500 nm). The administration method differs significantly from that in the nasopharyngeal setting, and it has a rapid release rate and a short duration of efficacy.

[0005] The fullerene disinfectant spray disclosed in patent CN111265547A has sterilization and disinfection as its main functions, but lacks support for vascular reconstruction and matrix repair, and does not contain growth factors that promote repair.

[0006] C mentioned in patent US10842738B1 60 Curcumin nasal spray is used for respiratory inflammation, but C 60 The carrier capacity is relatively limited, its ability to synergistically deliver macromolecular repair factors is restricted, and its efficacy has not been validated in radiation injury models.

[0007] Based on the above existing technologies, fullerene preparations currently face three main technical challenges in the treatment of nasopharyngeal radiation necrosis: ① The release process is uncontrollable, making it difficult to maintain efficacy in the long term; ② Their functions are relatively singular, mainly focusing on antioxidation or bactericidal effects, lacking support for vascular reconstruction and matrix repair; ③ The administration method has not yet been optimized for deep nasopharyngeal mucosa, resulting in a lack of targeting.

[0008] Therefore, there is an urgent need to develop a novel formulation that can both release fullerol in a long-term controlled manner to scavenge free radicals and synergistically deliver repair factors to promote tissue regeneration, and also has nasal mucosa-targeted adhesion properties, in order to solve the technical problems of existing nasopharyngeal formulations that have short-term efficacy, lack of vascular reconstruction and matrix repair support, and poor targeting when used in the nasopharynx. Summary of the Invention

[0009] In view of the above-mentioned defects or improvement needs of the existing technology, the present invention provides a long-acting targeted fullerol nasopharyngeal preparation, its preparation method and application, thereby solving the technical problems of short-term efficacy, lack of vascular reconstruction and matrix repair support, and poor targeting of existing nasopharyngeal preparations when applied to the nasopharynx.

[0010] To achieve the above objectives, according to a first aspect of the present invention, a long-acting targeted fullerol nasopharyngeal formulation is provided, wherein the active ingredient of the nasopharyngeal formulation comprises three-layered core-shell structured nanoparticles, consisting, from the inside out, a fullerol nanocore and polylactic acid containing growth factors. The intermediate layer is a glycolic acid copolymer and the outer layer is hyaluronic acid. The fullerol nanocore refers to fullerol at the nanoscale as the core.

[0011] Furthermore, the three-layer core-shell structured nanoparticles have a particle size of 150 nm-220 nm, the fullerol nanocores have a particle size of 130 nm-160 nm, and the polylactic acid containing growth factors... The thickness of the intermediate layer of the glycolic acid copolymer is 10 nm - 30 nm, and the thickness of the outer layer of hyaluronic acid is 10 nm - 30 nm.

[0012] Furthermore, the polylactic acid containing growth factors The growth factor in the intermediate layer of the glycolic acid copolymer is any one or a combination of epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF), and the mass of the growth factor is 0.1%-5% of the total mass of the three-layer core-shell structured nanoparticles, with an activity retention rate of ≥90%; the polylactic acid containing the growth factor... The molar ratio of lactic acid to glycolic acid in the intermediate layer of the glycolic acid copolymer is 3:2-4:1.

[0013] Furthermore, the fullerol nanocore and the polylactic acid containing growth factors... The mass ratio of the glycolic acid copolymer intermediate layer to the hyaluronic acid outer layer is 1:(0.8-2):(0.3-1.2).

[0014] According to a second aspect of the present invention, a method for preparing a long-acting targeted fullerol nasopharyngeal formulation is provided, comprising the following steps: (1) Dissolve fullerene in an aromatic solvent, then mix it with a phase transfer catalyst and an alkaline solution to induce a hydroxylation reaction in the fullerene, and obtain nanoscale fullerol as fullerol nanonuclei. (2) A microfluidic flash precipitation process was used to precipitate polylactic acid containing growth factors. The organic solvent of glycolic acid copolymer and the alcohol solution of fullerol nanonuclei are instantaneously mixed to form polylactic acid containing growth factors encapsulating the fullerol nanonuclei. Intermediate layer of glycolic acid copolymer; (3) In a buffer solution, polylactic acid containing growth factors is activated using a coupling agent. After adding the carboxyl group to the end of the intermediate molecular chain of the glycolic acid copolymer, hyaluronic acid is added. The carboxyl group forms a covalent bond with the hydroxyl or amino group of hyaluronic acid, completing the stable grafting of the outer layer of hyaluronic acid, and obtaining three-layer core-shell structured nanoparticles, which can be used as the active ingredient in nasopharyngeal preparations.

[0015] Further, step (2) includes: Polylactic acid containing growth factors The glycolic acid copolymer is used as the oil phase, with dichloromethane or chloroform as the organic solvent. A solution of fullerol nanonuclei in alcohol is used as the alcohol phase, with ethanol or methanol as the alcohol solution. Deionized water is used as the aqueous phase. The volume ratio of the oil, alcohol, and aqueous phases is 1:(1-2):(8-12), and the flow rate ratio is 1:(0.8-1.2):(8-12). The microfluidic chip channel width is 100 µm-200 µm, and the total flow rate is 40 mL / min-600 mL / min. A microfluidic flash precipitation process is used to instantaneously mix the oil, alcohol, and aqueous phases to form polylactic acid containing growth factors encapsulating fullerol nanonuclei. Intermediate layer of glycolic acid copolymer.

[0016] Furthermore, the reaction temperature of the hydroxylation reaction in step (1) is 90-110 °C, and the reaction time is 18-36 hours.

[0017] Furthermore, in step (1), the fullerene is C 60 C 70 C 76 C 78 C 80 C 84 C 90The aromatic solvent is any one of benzene, toluene, xylene, ethylbenzene, propane, mesitylene, chlorobenzene, dichlorobenzene, trichlorobenzene, nitrobenzene, anisole, o-dichlorobenzene, 1,2,4-trichlorobenzene, or carbon disulfide. The concentration of fullerene is 0.3 mg / mL to 8.0 mg / mL. The phase transfer catalyst is any one of tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutyliodide bromide, hexadecyltrimethylammonium bromide, trioctylmethylammonium chloride, tetrabenzylphosphine chloride, tetrabenzylphosphine bromide, methyltrioctylphosphine bromide, or quaternary ammonium salt ionic liquid, and its amount is 10% to 20% of the fullerene equivalent. The alkaline solution is an aqueous solution of sodium hydroxide or potassium hydroxide with a concentration of 20% to 40%.

[0018] Furthermore, in step (3), the pH of the buffer solution is 5-6, and the buffer solution concentration is 2. Morpholine ethanesulfonic acid or acetic acid-sodium acetate, with carbodiimide or hydroxysuccinimide as the coupling agent, and the molecular weight of hyaluronic acid is 8 kDa-15 kDa.

[0019] According to a third aspect of the present invention, an application of a long-acting targeted fullerol nasopharyngeal preparation is provided, wherein the nasopharyngeal preparation is prepared as a spray, atomized, gel, or ointment for local repair of soft tissue necrosis following radiotherapy to the nasopharynx.

[0020] In summary, compared with the prior art, the above-described technical solutions conceived by this invention can achieve the following beneficial effects: (1) This invention achieves synergistic delivery and differentiated release of fullerol and growth factors, solving the problem of mismatch between the time-dependent effects of antioxidation and repair promotion in existing treatments. Rapid release of fullerol (45%-80% cumulative release rate over 48 hours) provides immediate antioxidant protection and inhibits free radical cascade reactions; slow release of growth factors (30%-70% cumulative release rate over 72-120 hours) maintains long-term repair signals, promoting angiogenesis and matrix remodeling. This sequential release pattern conforms to the physiological process of tissue repair, which prioritizes "antioxidation before repair," resulting in a more durable and stable therapeutic effect compared to traditional single-release formulations. This invention utilizes hyaluronic acid as an outer layer to achieve targeted adhesion to the nasal mucosa, significantly increasing local drug concentration and duration of action. Hyaluronic acid specifically binds to the CD44 receptor on the nasal mucosa, combining with electrostatic adsorption on a negatively charged surface to achieve a dual-targeting mechanism, with a local retention half-life exceeding 6 hours, more than 3 times longer than traditional nasal sprays. Dosing the medication 1-2 times daily maintains an effective therapeutic concentration, significantly improving patient compliance and treatment efficiency, and solving the problems of traditional treatments requiring multiple doses and having short-lived effects. The active ingredient in the nasopharyngeal formulation of this invention comprises three-layer core-shell structured nanoparticles. The nanoscale design and particle size are adapted to the nasopharyngeal cavity, resulting in strong mucosal penetration and a significantly prolonged retention time.

[0021] (2) This invention limits the particle size of the three-layer core-shell structured nanoparticles. The nanoparticles can smoothly reach the deep nasopharynx with atomized aerosols of 3 μm-5 μm. They will not be rapidly cleared by the ciliary system due to excessive particle size, nor will they be rapidly penetrated into the systemic circulation by the mucosa due to excessive particle size. The size of 150-220 nm can be efficiently retained in the interstitial spaces of necrotic nasopharyngeal wounds, and the local enrichment is increased by more than 40% compared with ordinary small-particle nanoparticles. This overall particle size range can ensure that the nanoparticles are stably dispersed for a long time in dosage forms such as sprays and gels, and will not cause the problem of particle agglomeration clogging the nozzle. The particle size of the fullerol nanocore is 130 nm-160 nm, which has sufficient specific surface area and can load a sufficient amount of fullerol active ingredients to efficiently remove oxygen free radicals generated by radiotherapy. Polylactic acid containing growth factors The intermediate layer of the glycolic acid copolymer has a thickness of 10 nm–30 nm to achieve long-term sustained release of growth factors. The outer layer of hyaluronic acid has a thickness of 10 nm–30 nm, maximizing mucosal adhesion without affecting the overall dispersion of nanoparticles. The precise matching of the three layers allows the nanoparticles to simultaneously achieve a complete functional chain of "deep delivery – long-term sustained release – mucosal adhesion – synergistic repair," perfectly meeting the local repair needs of soft tissue necrosis after nasopharyngeal radiotherapy.

[0022] (3) In this invention, when the growth factor is a combination of EGF and VEGF, it can simultaneously achieve rapid epithelial repair and microvascular regeneration, solving the dual core problems of mucosal damage and local ischemia after radiotherapy. The mass ratio of growth factor of 0.1%-5% ensures effective repair concentration while avoiding the potential risk of tissue hyperplasia caused by excessive growth factor. The ≥90% activity retention rate can significantly reduce the ineffective loss of active ingredients, achieving efficient repair even with low drug loading, while reducing the overall production cost of the formulation. The 3:2-4:1 lactic acid / glycolic acid molar ratio can achieve uniform and long-lasting release of growth factor, avoiding burst release or release lag problems.

[0023] (4) The 1:(0.8-2) mass ratio of the nanocore to the intermediate layer designed in this invention ensures that the fullerol nanocore is completely encapsulated, preventing core leakage. The 1:(0.3-1.2) mass ratio of the nanocore to the hyaluronic acid layer fully exposes the mucosal adhesion sites. The fullerol nanocore and polylactic acid containing growth factors designed in this invention... With a reasonable weight distribution of functional weights between the intermediate layer of glycolic acid copolymer and the outer layer of hyaluronic acid, the synergistic effects of fullerol's antioxidant and anti-inflammatory properties, growth factor's angiogenesis-promoting properties, and hyaluronic acid matrix repair can be achieved without the defects of redundancy or insufficiency of a single component.

[0024] (5) In the preparation process of this invention, fullerene undergoes a hydroxylation reaction. After polyhydroxylation modification, the cytotoxicity of fullerol is significantly reduced compared to the original fullerene. Microfluidic flash precipitation technology enables precise and controllable large-scale production, and the product quality stability is significantly better than that of traditional preparation methods. A coupling agent is used to activate polylactic acid containing growth factors. The carboxyl groups at the ends of the intermediate molecular chains of the glycolic acid copolymer form covalent bonds with the hydroxyl or amino groups of hyaluronic acid, thereby completing the stable grafting of the outer layer of hyaluronic acid. The resulting product achieves synergistic delivery and differentiated release of fullerol and growth factors. Rapid release of fullerol provides antioxidant protection, while slow release of growth factors maintains repair signals. The outer layer of hyaluronic acid imparts targeted adhesion to the nasal mucosa, significantly prolonging the duration of local efficacy, especially suitable for deposition in the nasopharynx. The components of the product prepared in this way have good safety profiles and low clinical application risk. After polyhydroxylation modification, the cytotoxicity of fullerol is significantly reduced compared to the original fullerene, and polylactic acid... The glycolic acid copolymer is an FDA-approved GRAS-rated biodegradable material, and hyaluronic acid is an endogenous human component with no immunogenicity within its molecular weight range. The overall formulation has passed safety evaluations for cytotoxicity, irritation, and allergy, laying a safe foundation for clinical translation.

[0025] (6) In this invention, the volume ratio of oil phase, alcohol phase, and water phase is 1:(1-2):(8-12), which enables rapid antisolvent precipitation of organic solvents and avoids defects such as pores or uneven thickness in the intermediate layer. The matched flow rate ratio allows the three phases to achieve millisecond-level uniform turbulent mixing in the microchannel, ensuring uniform nanoparticle size. The channel width of 100-200 μm combined with a total flow rate of 40-600 mL / min balances mixing efficiency and continuous scale-up production capability, and the batch-to-batch quality difference is much smaller than that of traditional processes.

[0026] (7) The heating conditions of 90-110℃ and the reaction time of 18-36 hours proposed in this invention allow sufficient hydroxyl groups to be grafted onto the surface of fullerenes, ensuring that the water solubility and antioxidant activity of fullerols meet the standards. The combination of various types of fullerenes with suitable aromatic solvents ensures complete dissolution of the fullerenes. A concentration range of 0.3-8.0 mg / mL avoids aggregation, resulting in a homogeneous and stable reaction system. A 10%-20% equivalent phase transfer catalyst can efficiently shuttle between the two phases, significantly increasing the hydroxylation reaction rate without the risk of excessive catalyst residue. A high-concentration strong base system of 20%-40% ensures that the amount of hydroxyl grafted onto the fullerene surface is uniform and controllable, and that the water solubility and antioxidant activity of the product meet the standards.

[0027] (8) The weakly acidic range proposed in this invention is the optimal reaction range for the activation of PLGA carboxyl groups by carbodiimide / hydroxysuccinimide, and the hyaluronic acid grafting rate is increased by more than 30% compared with neutral conditions. 2-morpholine ethanesulfonic acid and acetate-sodium acetate are both non-amino buffer solutions and will not undergo side reactions with the activated carboxyl groups, which are perfectly suited to the requirements of covalent grafting reactions. The medium-low molecular weight hyaluronic acid of 8-15 kDa ensures sufficient mucosal adhesion sites without causing nanoparticle aggregation due to excessive molecular weight.

[0028] (9) The long-acting targeted fullerol nasopharyngeal preparation of the present invention can be used to prepare biopharmaceutical products for local repair of soft tissue necrosis after radiotherapy in the nasopharynx and larynx. For example, the nasopharyngeal preparation of the present invention can be prepared as a spray, atomized, gel, or ointment. This belongs to the field of biopharmaceutical manufacturing. The spray can be directly sprayed onto the superficial wound at the nasopharyngeal inlet, the atomized can penetrate deep into the crypts of the nasopharynx with the aerosol, and the gel / ointment can be applied to the external skin and the necrotic area around the nostrils, achieving comprehensive drug delivery to the entire nasopharynx and larynx. The high adhesion properties of the gel and ointment can form a long-lasting protective film on the wound surface, isolating it from external stimuli; the spray and atomized can disperse quickly, achieving uniform drug delivery over a large area of ​​mucosa, adapting to the needs of different repair stages. The combination of multiple dosage forms allows for flexible selection of the drug delivery method according to the different degrees of necrosis after radiotherapy, significantly reducing drug delivery discomfort and improving compliance with long-term repair treatment. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the three-layer core-shell structured nanoparticles provided in an embodiment of the present invention.

[0030] Figure 2 This is a flowchart of the preparation method provided in the embodiments of the present invention.

[0031] Figure 3 This is the in vitro release kinetic curve of fullerol and growth factors provided in Example 7 of the present invention.

[0032] Figure 4 This is a time-effect curve of the effect of different preparations provided in Example 10 of the present invention on the ROS clearance effect of NP69 cells.

[0033] Figure 5 This is a bar chart showing the effect of different formulations provided in Example 10 of the present invention on the survival rate of NP69 cells.

[0034] Figure 6 This is a curve showing the effect of hyaluronic acid surface density on NP69 cell adhesion time, as provided in Example 8 of this invention.

[0035] Figure 7This is a comparison of HE-stained sections of nasopharyngeal tissue from different treatment groups in the nude mouse in situ nasopharyngeal necrosis model after radiotherapy provided in Embodiment 11 of the present invention.

[0036] Figure 8 This is a comparison of CD31 immunohistochemical staining sections from different treatment groups in the nude mouse in situ nasopharyngeal necrosis model provided in Example 11 of this invention.

[0037] Figure 9 This is a comparison of CD31 immunohistochemical staining sections from different treatment groups in the nude mouse in situ nasopharyngeal necrosis model provided in Example 11 of this invention.

[0038] Figure 10 This is a comparison diagram of angiogenesis density after treatment in different treatment groups in the nude mouse in situ nasopharyngeal radiotherapy necrosis model provided in Embodiment 11 of the present invention. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0040] Traditional methods for treating soft tissue necrosis after nasopharyngeal radiotherapy have the following problems: First, the duration of drug efficacy is short; traditional nasal irrigation easily washes away newly formed granulation tissue, and hormone sprays can only suppress inflammation for a short period of 2-4 hours. Second, the function is singular; current treatments cannot simultaneously achieve free radical scavenging and tissue repair. Third, the drug delivery is poorly targeted, and the drug retention time is short. Fourth, the treatment cost is high, and patient compliance is poor. These factors collectively limit the radical cure of nasopharyngeal radiation necrosis.

[0041] Addressing the shortcomings of traditional treatment methods, this invention provides a long-acting targeted fullerol nasopharyngeal formulation. The active ingredient of this nasopharyngeal formulation comprises three-layered core-shell structured nanoparticles, such as... Figure 1 As shown, from the inside out, the structure consists of a fullerol nanocore and polylactic acid containing growth factors. The intermediate layer is a glycolic acid copolymer and the outer layer is hyaluronic acid. The fullerol nanocore refers to fullerol at the nanoscale as the core.

[0042] The three-layer core-shell structured nanoparticles have a particle size of 150 nm-220 nm, the fullerol nanocores have a particle size of 130 nm-160 nm, and the polylactic acid contains growth factors. The thickness of the intermediate layer of the glycolic acid copolymer is 10 nm–30 nm, and the thickness of the outer layer of hyaluronic acid is 10 nm–30 nm. For example, the particle size of the three-layer core-shell structured nanoparticles is 150 nm, the particle size of the fullerol nanocore is 130 nm, and the polylactic acid containing growth factors… The intermediate layer of the glycolic acid copolymer has a thickness of 10 nm, and the outer layer of hyaluronic acid has a thickness of 10 nm. Alternatively, the three-layer core-shell structured nanoparticles have a particle size of 220 nm, the fullerol nanocores have a particle size of 160 nm, and polylactic acid containing growth factors... The intermediate layer of the glycolic acid copolymer has a thickness of 60 nm, and the outer layer of hyaluronic acid has a thickness of 60 nm. Alternatively, the three-layer core-shell structured nanoparticles have a particle size of 180 nm, the fullerol nanocores have a particle size of 140 nm, and polylactic acid containing growth factors... The thickness of the intermediate layer of the glycolic acid copolymer is 20 nm, and the thickness of the outer layer of hyaluronic acid is 20 nm.

[0043] The polylactic acid containing growth factors The growth factor in the intermediate layer of the glycolic acid copolymer is any one or a combination of epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF), and the mass of the growth factor is 0.1%-5% of the total mass of the three-layer core-shell structured nanoparticles, with an activity retention rate of ≥90%; the polylactic acid containing the growth factor... The molar ratio of lactic acid to glycolic acid in the intermediate layer of the glycolic acid copolymer is 3:2-4:1. For example, the growth factor is a combination of epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF), and the mass of the growth factor is 0.1%, 1%, 2%, 3%, 4%, or 5% of the total mass of the three-layer core-shell structured nanoparticles.

[0044] The fullerol nanocore and polylactic acid containing growth factors The mass ratio of the glycolic acid copolymer intermediate layer to the hyaluronic acid outer layer is 1:(0.8-2):(0.3-1.2). The mass ratios can also be 1:0.8:0.3, 1:2:1.2, or 1:1:1.

[0045] A method for preparing a long-acting targeted fullerol nasopharyngeal formulation includes the following steps: (1) Dissolve fullerene in an aromatic solvent, then mix it with a phase transfer catalyst and an alkaline solution to induce a hydroxylation reaction in the fullerene, and obtain nanoscale fullerol as fullerol nanonuclei. (2) A microfluidic flash precipitation process was used to precipitate polylactic acid containing growth factors. The organic solvent of glycolic acid copolymer and the alcohol solution of fullerol nanonuclei are instantaneously mixed to form polylactic acid containing growth factors encapsulating the fullerol nanonuclei. Intermediate layer of glycolic acid copolymer; (3) In a buffer solution, polylactic acid containing growth factors is activated using a coupling agent. After adding the carboxyl group to the end of the intermediate molecular chain of the glycolic acid copolymer, hyaluronic acid is added. The carboxyl group forms a covalent bond with the hydroxyl or amino group of hyaluronic acid, completing the stable grafting of the outer layer of hyaluronic acid, and obtaining three-layer core-shell structured nanoparticles, which can be used as the active ingredient in nasopharyngeal preparations.

[0046] Further, step (2) includes: Polylactic acid containing growth factors The glycolic acid copolymer is used as the oil phase, with dichloromethane or chloroform as the organic solvent. A solution of fullerol nanonuclei in alcohol is used as the alcohol phase, with ethanol or methanol as the alcohol solution. Deionized water is used as the aqueous phase. The volume ratio of the oil, alcohol, and aqueous phases is 1:(1-2):(8-12), and the flow rate ratio is 1:(0.8-1.2):(8-12). The microfluidic chip channel width is 100 µm-200 µm, and the total flow rate is 40 mL / min-600 mL / min. A microfluidic flash precipitation process is used to instantaneously mix the oil, alcohol, and aqueous phases to form polylactic acid containing growth factors encapsulating fullerol nanonuclei. A glycolic acid copolymer intermediate layer. For example, the volume ratio of the oil phase, alcohol phase, and water phase is 1:1:10, 1:2:8, or 1:1.5:12; the flow rate ratio of the oil phase, alcohol phase, and water phase is 1:0.8:8, 1:1.2:12, or 1:1:10; the microfluidic chip channel width is 100 µm, 150 µm, or 200 µm; and the total flow rate is 40 mL / min, 200 mL / min, or 600 mL / min.

[0047] Furthermore, the hydroxylation reaction in step (1) is carried out at a temperature of 90-110 °C for 18-36 hours. For example, the reaction is carried out at 90 °C for 36 hours, at 110 °C for 18 hours, or at 100 °C for 28 hours.

[0048] Furthermore, in step (1), the fullerene is C 60 C 70 C 76 C 78 C 80 C 84 C 90 The aromatic solvent is any one of benzene, toluene, xylene, ethylbenzene, propane, mesitylene, chlorobenzene, dichlorobenzene, trichlorobenzene, nitrobenzene, anisole, o-dichlorobenzene, 1,2,4-trichlorobenzene, and carbon disulfide, and the concentration of fullerene is 0.3 mg / mL to 8.0 mg / mL, specifically 0.3 mg / mL, 2.0 mg / mL, or 8.0 mg / mL.

[0049] The phase transfer catalyst is any one of tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutyliodide bromide, hexadecyltrimethylammonium bromide, trioctylmethylammonium chloride, tetrabenzylphosphine chloride, tetrabenzylphosphine bromide, methyltrioctylphosphine bromide, or quaternary ammonium salt ionic liquid, used in an amount of 10%-20% of the fullerene equivalent, specifically 10%, 15%, or 20%. The alkaline solution is an aqueous solution of sodium hydroxide or potassium hydroxide, with a concentration of 20%-40%, specifically 20%, 30%, or 40%.

[0050] Further, in step (3), the pH of the buffer solution is 5-6, specifically 5, 5.5, or 6.0. The buffer solution is 2... Morpholine ethanesulfonic acid or acetic acid-sodium acetate, with carbodiimide or hydroxysuccinimide as the coupling agent, and the molecular weight of hyaluronic acid is 8kDa-15kDa, specifically 8kDa, 10kDa or 15kDa.

[0051] Application of a long-acting targeted fullerol nasopharyngeal preparation, wherein the nasopharyngeal preparation is prepared as a spray, atomized, gel, or ointment for local repair of soft tissue necrosis following radiotherapy to the nasopharynx.

[0052] I. Preparation of Spray Formulation like Figure 2 As shown, a method for preparing a long-acting targeted fullerol nasopharyngeal spray includes the following steps: (1) Preparation of fullerol nanonuclei: A phase transfer catalytic system was used. Fullerene was dissolved in an aromatic solvent, and the phase transfer catalyst was mixed with an alkaline solution. The mixture was stirred for a certain time under heating conditions to induce hydroxylation of the fullerene. The reaction solution was then treated to obtain fullerol nanonuclei. (2) Construction of polylactic acid Controlled-release shell of glycolic acid copolymer: A microfluidic flash precipitation process is used to react fullerol ethanol solution with polylactic acid containing growth factors. Hydroxyacetic acid copolymer organic solvent solution is instantaneously mixed at a certain volume ratio to form a controlled-release shell layer (i.e., intermediate layer). (3) Grafting of outer layer with hyaluronic acid: After activating the carboxyl group of the shell with a coupling agent in a buffer solution, hyaluronic acid is added dropwise and incubated at room temperature to obtain three-layer structured nanoparticles; (4) Sterilization and filling: The prepared nano suspension is sterilely filtered and concentrated by ultrafiltration, and then dispensed into the anti-backflow nasal spray pump to obtain the finished spray.

[0053] The preparation process of fullerol nanonuclei is as follows: using C 60 Taking fullerenes as an example, C 60The solution was dissolved in toluene, and a phase-transfer catalyst, tetrabutylammonium bromide, was added. Then, an aqueous solution of sodium hydroxide was added, and the mixture was heated and stirred at 90-110 °C for 18-36 hours under nitrogen protection. After the reaction was complete, the organic phase and the aqueous phase were separated. The aqueous phase was purified by dialysis and freeze-dried to obtain fullerol nanonuclei.

[0054] The technical specifications of the finished spray are as follows: average particle size of nanoparticles 150-220 nm, polydispersity index (PDI) ≤ 0.25, zeta potential -10 to -25 mV, cumulative release rate of fullerol 48 hours 45%-80%, and cumulative release rate of growth factors 72-120 hours 30%-70%.

[0055] This invention utilizes microfluidic flash precipitation technology to achieve precise and controllable large-scale production, resulting in product quality stability significantly superior to traditional preparation methods. The nanoparticles exhibit narrow particle size distribution (PDI ≤ 0.25), high drug loading (fullerol 6-12%, growth factors 0.1-5%), and good batch-to-batch consistency. Compared to nanoparticles prepared by traditional emulsification methods (PDI > 0.3, drug loading < 5%), this invention demonstrates strong process stability, making it suitable for industrial production and providing reliable technical support for clinical applications.

[0056] This invention offers significant advantages in cost control and preparation efficiency. Compared to existing clinical treatments: traditional nasal irrigation requires 2-3 sessions daily for 7-14 days, is cumbersome, and has poor compliance; corticosteroid sprays only maintain their efficacy for 2-4 hours, requiring 4-6 doses daily, with monthly treatment costs of approximately 200-400 yuan; hyperbaric oxygen therapy requires 20-40 consecutive treatments, with a single session costing 150-300 yuan, resulting in total costs as high as 3000-12000 yuan.

[0057] The formulation of this invention employs a long-acting release mechanism that maintains a single dose for 24-48 hours, reducing the monthly dosing frequency from 120-180 times to 15-30 times, a reduction of more than 80% in dosing frequency. The preparation process uses a simple physical mixing-drying process, eliminating the need for expensive microencapsulation equipment, and reducing production costs by 40-60% compared to traditional formulations. The monthly treatment cost for patients can be controlled at 80-150 yuan, saving 50-70% of the cost compared to existing solutions, significantly improving the economy and accessibility of treatment.

[0058] II. Preparation of Atomizing Formulations Three-layered core-shell nanoparticles were dispersed in isotonic saline, and the solid content was adjusted to 0.5–2 mg / mL. A small amount of Tween-80 was added as a dispersant. After ultrasonic degassing, the solution was filtered through a 0.45 μm filter membrane. The resulting drug solution can be directly added to a medical ultrasonic nebulizer. After nebulization, the particle size is controlled at 3–5 μm, allowing it to penetrate deep into the nasopharynx and upper respiratory tract mucosal wounds via aerosol, achieving deep drug delivery.

[0059] III. Gel Formulation Preparation Carbomer 940 powder was slowly sprinkled into purified water and allowed to swell completely. A three-layer core-shell nanoparticle dispersion was then added, and the mixture was stirred until homogeneous. The pH was adjusted to 6.0–7.0 with triethanolamine to form a transparent hydrogel system. The gel viscosity was controlled at 5000–20000 mPa·s, allowing for direct application to superficial necrotic wounds at the nasopharyngeal inlet. Adhesion and retention time could reach over 4 hours, achieving long-term sustained drug release.

[0060] IV. Ointment Formulation Preparation Petrolatum and lanolin were melted in a 7:3 ratio and cooled to below 40°C. Under aseptic conditions, three-layered core-shell nanoparticles pre-dispersed in a small amount of glycerin were slowly added, and the mixture was stirred in the same direction until completely mixed. The resulting ointment has a fine texture and is free of particles. It can be used on the external skin of the nasopharynx and soft tissue necrosis near the nostrils after radiotherapy to the head and neck, isolating external stimuli while continuously releasing nano-active ingredients.

[0061] Example 1 (Basic Preparation Process) Preparation of fullerol nanonuclei: Take C 60 720 mg of fullerene was dissolved in 216 mL of toluene (4.63 mmol / L), 108 mg of tetrabutylammonium bromide and 36 mL of 30% sodium hydroxide aqueous solution were added, and the mixture was heated and stirred at 80 °C for 5 hours under nitrogen protection. After the reaction was completed, the aqueous phase was separated, dialyzed for 5 days to remove inorganic salts, and then freeze-dried to obtain fullerol nanonuclei.

[0062] Construction of the controlled-release shell: 15 mg of fullerol nanonuclei were dissolved in 1 mL of ethanol and mixed with polylactic acid. A solution of 20 mg of PLGA (molecular weight 25000 Da, lactic acid:glycolic acid = 75:25) and 0.5 mg of EGF in 1 mL of dichloromethane was mixed with an aqueous phase at a volume ratio of 1:1:10 using a microfluidic chip. The microfluidic chip channel width was 150 μm, and the total flow rate was 50 mL / min.

[0063] Hyaluronic acid outer layer grafting: After activating the carboxyl groups on the surface of nanoparticles with EDC / NHS for 15 minutes in 2-morpholine ethanesulfonic acid buffer (pH 5.5), a hyaluronic acid solution with a molecular weight of 10 kDa (10 mg / mL) was added dropwise and incubated at room temperature for 2 hours.

[0064] Sterilization and filling: The nano suspension is sterilized by filtration through a 0.22 μm filter membrane, concentrated to 10 mg / mL by rotating membrane ultrafiltration, and the osmotic pressure is adjusted by adding sodium chloride and the pH is adjusted to 6.8 by phosphate buffer. It is then dispensed into anti-backflow nasal spray pumps, with each vial containing 5 mL.

[0065] Quality testing: average particle size 185±12 nm, PDI 0.18, zeta potential -18.6 mV, fullerol loading 8.2%, EGF loading 2.1%.

[0066] Example 2 (PLGA molar ratio boundary verification) Following the method in Example 1, sprays were prepared using PLGA molar ratios of 60:40 and 80:20, respectively. At a molar ratio of 60:40, the resulting formulation had a particle size of 205 ± 18 nm, a fullerol release rate of 68% after 48 hours, and an EGF release rate of 42% after 72 hours. At a molar ratio of 80:20, the resulting formulation had a particle size of 175 ± 12 nm, a fullerol release rate of 52% after 48 hours, and an EGF release rate of 28% after 72 hours. The results indicate that different molar ratios can regulate the release behavior.

[0067] Example 3 (Verification of the molecular weight boundary of hyaluronic acid) Following the method in Example 1, sprays were prepared using hyaluronic acid with molecular weights of 8 kDa and 15 kDa, respectively. 8 kDa hyaluronic acid: mucosal adhesion time 4.2 hours, retention rate 65%; 15 kDa hyaluronic acid: mucosal adhesion time 7.8 hours, retention rate 78%. The results indicate that the higher the molecular weight, the stronger the adhesion effect.

[0068] Example 4 (Scale-up of microfluidic processes) The process of Example 1 was scaled up from 1 mL to 100 mL. The channel width was maintained at 150 μm, the total flow rate was increased to 500 mL / min, and the flow rate ratio was maintained at 1:1:10. The product quality after scale-up was as follows: average particle size 188±14 nm, PDI 0.19, drug loading variation <5%, good batch-to-batch reproducibility, and RSD <8%.

[0069] Example 5 (PLGA molecular weight system optimization) Sprays were prepared using PLGA with molecular weights of 8000, 15000, 25000, 35000, and 50000 Da, respectively. The formulation prepared from 25000 Da PLGA had the narrowest particle size distribution (PDI 0.18), the highest drug loading (8.2%), and the release behavior that best met the therapeutic requirements.

[0070] Example 6 (Verification of Particle Size Distribution Uniformity) The particle size distribution of different batches of the formulation was determined using dynamic light scattering (DLS) technology. The average particle sizes of the five batches were 185, 188, 182, 190, and 187 nm, respectively, with a PDI of <0.20 for all batches, indicating good consistency between batches. Electron microscopy revealed that the nanoparticles were spherical, with smooth surfaces and uniform dispersion.

[0071] Example 7 (In vitro release characterization) The diffusion method using dialysis bags was employed, with constant temperature shaking at 37 °C in pH 6.8 phosphate buffer. Samples were taken periodically to detect the release of fullerol and EGF. Figure 3 As shown, fullerol release follows a biphasic kinetic pattern: 48% is released during the rapid release phase (0-24h) and 27% during the slow release phase (24-48h); 35% is released during the delayed EGF release phase (0-72h) and 30% during the sustained release phase (72-120h). This sequential release realizes the therapeutic concept of "antioxidant first, then repair".

[0072] Example 8 (Verification of the antioxidant effect of NP69 cells) A radiation damage model was established using human nasopharyngeal epithelial cells NP69 irradiated with 60Co gamma rays (8 Gy). Figure 4 As shown, the present invention C 60 The ROS scavenging effect curve of the fullerol group over time showed that the ROS level decreased by 65% ​​within 2 hours and remained at a 78% scavenging rate after 24 hours; the dexamethasone spray group was only effective within 4 hours, with a peak scavenging rate of 45%; the blank control group showed no significant improvement. Figure 5 As shown in the bar chart, the cell viability rate was 85.3±4.2% in the present invention group, 68.2±5.1% in the dexamethasone group, and 45.2±5.3% in the blank group. The present invention group was significantly better than the control group. P <0.001).

[0073] Example 9 (Verification of Hyaluronic Acid Adhesion Performance) Nanoparticles with different hyaluronic acid surface densities (3, 10, 20, 30 μg / mg) were prepared, and their adhesion to NP69 cells was evaluated. Figure 6 As shown in the adhesion time effect curves, the adhesion rate of the 20 μg / mg density group reached a peak of 78% at 2 hours and remained at 65% after 6 hours; the 30 μg / mg group had a peak of 82% but higher cost; and the 3 μg / mg group had a peak of only 35%. 20 μg / mg was selected as the optimal surface density.

[0074] Example 10 (Pig Nasal Mucosal Permeation and Retention) The permeation characteristics of the formulation were evaluated using a fresh porcine nasal mucosa in vitro model. The cumulative permeation of the fullerol formulation of this invention reached 75.6 μg / cm³ within 24 hours. 2 The free fullerol concentration was only 14.8 μg / cm³. 2 After simulated nasal irrigation, the formulation of this invention retained 72% of the drug in the mucosa, with only 18% of the drug remaining free, demonstrating the targeted adhesion effect of hyaluronic acid modification.

[0075] Example 11 (Nude mouse in situ nasopharyngeal necrosis model after radiotherapy) Twenty-four 6-8 week old BALB / c nude mice were used to establish a soft tissue necrosis model after radiotherapy by local irradiation of the nasopharynx with 20 Gy gamma rays. They were randomly divided into four groups of six mice each: a model control group, a control group, and a control group. 60 Fullerol + EGF group, the composite factor group of the present invention (EGF + VEGF), and dexamethasone group.

[0076] Dosage regimen: Dosage was started on the 3rd day after successful modeling. The group receiving the invention received 50 μL of the drug once daily via nasal cavity; the group receiving the drug received 50 μL twice daily for 4 consecutive weeks.

[0077] like Figure 7 and Figure 8 As shown, HE staining results revealed that the model control group exhibited large areas of necrosis, accounting for 65% of the total area; the dexamethasone group showed a reduction in necrosis area to 45%; C 60 The necrotic area in the fullerol + EGF group was significantly reduced to 25%; the necrotic area in the composite factor group of this invention was only 12%, showing the best repair effect. Figure 9 and Figure 10 As shown, CD31 immunohistochemical staining revealed that the blood vessel density in the composite factor group of this invention was 25.6 ± 4.1 vessels / field, significantly superior to other groups. P <0.001).

[0078] Example 12 (Cytotoxicity Safety Evaluation) NP69 cytotoxicity assay: C 60 When the concentration of fullerol spray was ≤100 μg / mL, the cell survival rate was >92%, with no significant cytotoxicity; when the concentration was ≤200 μg / mL, the survival rate was >88%, with mild toxicity but clinically acceptable. Compared to the original C... 60 Fullerenes (survival rate <25%), and their toxicity is significantly reduced after modification with fullerol.

[0079] Hemolysis test: In rabbit red blood cell suspension, the hemolysis rate was <1.8% when the concentration of the spray was ≤200 μg / mL, which meets the safety standard for biomaterials (<5%).

[0080] Example 13 (Long-term stability study) The optimal formulation was selected for stability studies. Following ICH Q1A guidelines, the samples were stored for 6 months at 25℃±2℃ / 60%RH±5%RH and 40℃±2℃ / 75%RH±5%RH.

[0081] Under normal temperature conditions for 6 months: particle size change <8% (185→201 nm), drug loading remains >96%, and release behavior shows no significant difference; under accelerated conditions: particle size change <12% (185→207 nm), drug loading remains >94%. Based on stability data, the product shelf life is determined to be 24 months.

[0082] Controlled experiments showed that the long-acting targeted fullerol nasopharyngeal spray prepared in this invention is significantly superior to traditional formulations in terms of free radical scavenging ability, cell proliferation promotion, and angiogenesis induction. In a nude mouse nasopharyngeal radiation injury model, the tissue repair score, vascular density, and epithelial integrity recovery of the spray treatment group were significantly better than those of the control group, and the local retention time was extended to more than 24 hours. Once-daily administration is sufficient to maintain an effective therapeutic concentration, solving the problems of short-lived efficacy and frequent administration required by traditional treatments.

[0083] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A long-acting targeted fullerol nasopharyngeal formulation, characterized in that, The active ingredient of the nasopharyngeal preparation comprises three-layered core-shell nanoparticles, consisting of a fullerol nanocore and polylactic acid containing growth factors, arranged from the inside out. The intermediate layer is a glycolic acid copolymer and the outer layer is hyaluronic acid. The fullerol nanocore refers to fullerol at the nanoscale as the core.

2. The long-acting targeted fullerol nasopharyngeal formulation as described in claim 1, characterized in that, The three-layer core-shell structured nanoparticles have a particle size of 150 nm-220 nm, the fullerol nanocores have a particle size of 130 nm-160 nm, and the polylactic acid contains growth factors. The thickness of the intermediate layer of the glycolic acid copolymer is 10 nm - 30 nm, and the thickness of the outer layer of hyaluronic acid is 10 nm - 30 nm.

3. A long-acting targeted fullerol nasopharyngeal formulation as described in claim 1 or 2, characterized in that, The polylactic acid containing growth factors The growth factor in the intermediate layer of the glycolic acid copolymer is any one or a combination of epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF), and the mass of the growth factor is 0.1%-5% of the total mass of the three-layer core-shell structured nanoparticles, with an activity retention rate of ≥90%; the polylactic acid containing the growth factor... The molar ratio of lactic acid to glycolic acid in the intermediate layer of the glycolic acid copolymer is 3:2-4:

1.

4. A long-acting targeted fullerol nasopharyngeal formulation as described in claim 1 or 2, characterized in that, The fullerol nanocore and polylactic acid containing growth factors The mass ratio of the glycolic acid copolymer intermediate layer to the hyaluronic acid outer layer is 1:(0.8-2):(0.3-1.2).

5. A method for preparing a long-acting targeted fullerol nasopharyngeal formulation as described in any one of claims 1-4, characterized in that, Includes the following steps: (1) Dissolve fullerene in an aromatic solvent, then mix it with a phase transfer catalyst and an alkaline solution to induce a hydroxylation reaction in the fullerene, and obtain nanoscale fullerol as fullerol nanonuclei. (2) A microfluidic flash precipitation process was used to precipitate polylactic acid containing growth factors. The organic solvent of glycolic acid copolymer and the alcohol solution of fullerol nanonuclei are instantaneously mixed to form polylactic acid containing growth factors encapsulating the fullerol nanonuclei. Intermediate layer of glycolic acid copolymer; (3) In a buffer solution, polylactic acid containing growth factors is activated using a coupling agent. After adding the carboxyl group to the end of the intermediate molecular chain of the glycolic acid copolymer, hyaluronic acid is added. The carboxyl group forms a covalent bond with the hydroxyl or amino group of hyaluronic acid, completing the stable grafting of the outer layer of hyaluronic acid, and obtaining three-layer core-shell structured nanoparticles, which can be used as the active ingredient in nasopharyngeal preparations.

6. The method for preparing a long-acting targeted fullerol nasopharyngeal formulation as described in claim 5, characterized in that, Step (2) includes: Polylactic acid containing growth factors The glycolic acid copolymer is used as the oil phase, with dichloromethane or chloroform as the organic solvent. A solution of fullerol nanonuclei in alcohol is used as the alcohol phase, with ethanol or methanol as the alcohol solution. Deionized water is used as the aqueous phase. The volume ratio of the oil, alcohol, and aqueous phases is 1:(1-2):(8-12), and the flow rate ratio is 1:(0.8-1.2):(8-12). The microfluidic chip channel width is 100 µm-200 µm, and the total flow rate is 40 mL / min-600 mL / min. A microfluidic flash precipitation process is used to instantaneously mix the oil, alcohol, and aqueous phases to form polylactic acid containing growth factors encapsulating fullerol nanonuclei. Intermediate layer of glycolic acid copolymer.

7. A method for preparing a long-acting targeted fullerol nasopharyngeal formulation as described in claim 5 or 6, characterized in that, The reaction temperature of the hydroxylation reaction in step (1) is 90 ℃-110 ℃, and the reaction time is 18 hours-36 hours.

8. A method for preparing a long-acting targeted fullerol nasopharyngeal formulation as described in claim 5 or 6, characterized in that, In step (1), the fullerene is C 60 C 70 C 76 C 78 C 80 C 84 C 90 The aromatic solvent is any one of benzene, toluene, xylene, ethylbenzene, propane, mesitylene, chlorobenzene, dichlorobenzene, trichlorobenzene, nitrobenzene, anisole, o-dichlorobenzene, 1,2,4-trichlorobenzene, or carbon disulfide. The concentration of fullerene is 0.3 mg / mL to 8.0 mg / mL. The phase transfer catalyst is any one of tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutyliodide bromide, hexadecyltrimethylammonium bromide, trioctylmethylammonium chloride, tetrabenzylphosphine chloride, tetrabenzylphosphine bromide, methyltrioctylphosphine bromide, or quaternary ammonium salt ionic liquid, and its amount is 10% to 20% of the fullerene equivalent. The alkaline solution is an aqueous solution of sodium hydroxide or potassium hydroxide with a concentration of 20% to 40%.

9. A method for preparing a long-acting targeted fullerol nasopharyngeal formulation as described in claim 5 or 6, characterized in that, In step (3), the pH of the buffer solution is 5-6, and the buffer solution is 2. Morpholine ethanesulfonic acid or acetic acid-sodium acetate, with carbodiimide or hydroxysuccinimide as the coupling agent, and the molecular weight of hyaluronic acid is 8 kDa-15 kDa.

10. The application of a long-acting targeted fullerol nasopharyngeal formulation as described in any one of claims 1-4, characterized in that, The nasopharyngeal preparation is prepared as a spray, atomized, gel, or ointment for local repair of soft tissue necrosis after radiotherapy to the nasopharynx and larynx.

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