Nasal gel for treating allergic rhinitis and preparation method thereof

Abstract

The invention discloses a nasal gel for treating allergic rhinitis and a preparation method thereof, and relates to the technical field of medicines. The nasal gel for treating allergic rhinitis is prepared from double-sensitive double-network drug-loaded gel microspheres and a temperature-sensitive gel material, the double-sensitive double-network drug-loaded gel microspheres are prepared from sodium alginate, a temperature-sensitive polymer, lactoferrin, a traditional Chinese medicine extracting solution and calcium chloride, the temperature-sensitive gel material is prepared from silk fibroin, carboxymethyl chitosan, K-carrageenan and genipin; the double-sensitive double-network drug-loading gel microspheres are loaded in the temperature-sensitive gel material, and after the temperature-sensitive gel material enters the nasal cavity, the temperature-sensitive gel material is quickly converted into gel to be adhered to nasal cilia, so that the removal of the double-sensitive double-network drug-loading gel microspheres by the motion of the nasal cilia is reduced, and the gel microspheres can better release a double-layer drug-loading system; the acting time of the medicine in the nasal cavity is prolonged, the bioavailability of the medicine is improved, the allergic rhinitis is effectively treated, and uncomfortable symptoms are relieved.

Description

Technical Field

[0001] The invention belongs to the field of medical technology, and specifically refers to a nasal gel for treating allergic rhinitis and a preparation method thereof. Background Art

[0002] Allergic rhinitis is an inflammatory disease of the nasal mucosa caused by exogenous allergens, usually triggered by external allergens (such as pollen, dust mites, animal hair, etc.), which causes the body's immune system to become abnormally excited and releases excessive immune mediators, such as histamine and interleukins, thereby inducing an inflammatory reaction in the nasal mucosa. The main symptoms are nasal congestion, nasal flow, sneezing, and nasal itching, which have a serious impact on the patient's work and life. In particular, allergic rhinitis is also accompanied by complications such as bronchial asthma, allergic conjunctivitis, and chronic sinusitis, which seriously affect people's health and bring a serious economic burden to society.

[0003] Western medicine generally uses glucocorticoids, antihistamines, leukotriene receptor antagonists, mast cell stabilizers, anticholinergics, etc. to relieve and control symptoms of allergic rhinitis. However, long-term use has certain drug dependence and addiction, and cannot cure it. Traditional Chinese medicine treatment can not only effectively relieve patients' symptoms and signs, but also improve patients' quality of life, with a low recurrence rate, small toxic side effects, and few adverse reactions. In terms of administration method, compared with oral administration, nasal administration can avoid the first-pass effect of the liver, and has multiple advantages such as being non-invasive, painless, fast absorption, and the ability to bypass the blood-brain barrier.

[0004] The existing technology currently has the following problems:

[0005] Conventional Chinese medicine liposomes, nanoparticles and other nanoformulations are easily cleared by the movement of nasal cilia, thereby reducing the drug's action time in the nasal cavity, resulting in low bioavailability and being unfavorable to the efficacy of the drug. Summary of the invention

[0006] In view of the above situation, in order to overcome the defects of the prior art, the present invention proposes a nasal gel for treating allergic rhinitis, comprising the following components in parts by weight: 20-30 parts of dual-sensitive dual-network drug-loaded gel microspheres and 10-20 parts of thermosensitive gel material.

[0007] The dual-sensitive dual-network drug-loaded gel microspheres include the following components in parts by weight: 15-20 parts of sodium alginate, 2.5-5 parts of thermosensitive polymer, 3-4 parts of lactoferrin, 9-12 parts of traditional Chinese medicine extract, and 10-15 parts of calcium chloride.

[0008] The temperature-sensitive gel material comprises the following components in parts by weight: 30-50 parts of silk fibroin, 10-20 parts of carboxymethyl chitosan, 5-10 parts of K-carrageenan, and 10-15 parts of genipin.

[0009] The raw materials of the traditional Chinese medicine extract include the following components in parts by weight: 3-5 parts of platycodon, 3-5 parts of astragalus, 3-5 parts of atractylodes, 3-5 parts of tangerine peel, 3-5 parts of xanthium, 3-5 parts of magnolia, 3-5 parts of angelica, and 3-5 parts of liquorice.

[0010] The preparation method of the dual-sensitive dual-network drug-loaded gel microspheres specifically comprises the following steps:

[0011] (1) Grind Platycodon grandiflorum, Astragalus membranaceus, Atractylodes macrocephala, Tangerine peel, Xanthium sibiricum, Magnolia officinalis, Angelica dahurica and Licorice root, pass through a 60-80 mesh sieve, mix evenly, add 4 times the amount of distilled water and boil for 2-3 times, filter while hot, combine the filtrate, and concentrate to 1 / 5 to 1 / 4 of the original volume of the filtrate, select Chinese herbal medicines that dispel wind and relieve exterior symptoms and clear the nasal passages, and then use them in combination with herbal medicines that replenish qi and strengthen the exterior and improve immunity to assist in the treatment of allergic rhinitis and effectively relieve symptoms such as nasal congestion, nasal flow, sneezing, and nasal itching, to obtain a Chinese herbal medicine extract;

[0012] (2) 30-50 mL of a nanocrystalline cellulose aqueous suspension with a solid content of 1 g was replaced with anhydrous THF by a solvent replacement method, and then transferred to a round-bottom flask. 1.8 g of triethylamine and 1.5 g of 4-dimethylaminopyridine were added and magnetically stirred to obtain a mixed solution for standby use. 5.5 g of 2-bromoisobutyryl bromide was dissolved in 30-50 mL of anhydrous THF in advance and slowly added to the mixed solution through a constant pressure funnel in nitrogen. After the addition was complete, the bottle mouth was sealed and magnetically stirred at room temperature for 24 h. The product was washed with anhydrous THF, an equal volume mixture of anhydrous THF and anhydrous ethanol, and acetone for 3-5 times. By using 2-bromoisobutyryl bromide to initiate bromination of nanocrystalline cellulose in an anhydrous THF environment, it presents a rod-like structure, which can increase the contact with nasal cilia and reduce removal, thereby obtaining modified nanocrystalline cellulose;

[0013] (3) 0.2 g of cuprous bromide was placed in a reaction bottle, and washed with glacial acetic acid, anhydrous ethanol, and methanol for multiple times until the cuprous bromide turned light yellow. 300 mg of the modified nanocrystalline cellulose described in step (2), 11.0 g of recrystallized N-isopropylacrylamide, and 30-50 mL of methanol solution were added. The mixture was stirred magnetically, and the bottle mouth was sealed. The mixed solution was frozen and thawed multiple times by liquid nitrogen freeze-thaw method to remove oxygen to the maximum extent. After the mixture was warmed up, 0.2 mL of N,N,N',N',N''-pentamethyldiethyltriamine was added to the freeze-thaw solution through a syringe. The mixture was stirred magnetically at room temperature for 24 h. The reaction product was washed with methanol and anhydrous ethanol for 3-5 times. The copolymerization and grafting of N-isopropylacrylamide on the modified nanocrystalline cellulose was achieved, which broadened the application range of thermosensitive materials and obtained thermosensitive polymers.

[0014] (4) Add lactoferrin to the Chinese medicine extract described in step (1), stir magnetically for 5-6 hours, take 1 / 2 of the Chinese medicine mixture and mix it with 50 mL of 3.0-4.0% sodium alginate solution, add it into 50 mL of 2.0-3.0% calcium chloride solution through a micro-injection pump, collect the product, the gel microspheres are coated with drugs, are not easily removed by the movement of nasal cilia, can adhere to nasal cilia and release drug components through pH responsiveness in the nasal cavity, thereby increasing the action time in the nasal cavity and reducing the number of dosing times, thereby obtaining inner layer drug-loaded gel microspheres;

[0015] (5) The remaining 1 / 2 amount of the Chinese medicine mixture is mixed with 50 mL of a sodium alginate solution with a mass fraction of 3.0-4.0%, and the inner layer drug-loaded gel microspheres described in step (4) are placed in the solution for adsorption for 1-2 hours, taken out, and then transferred to 50 mL of a calcium chloride solution containing the thermosensitive polymer described in step (3) for sufficient reaction for 2-3 hours. The sodium alginate adsorbed on the surface of the microspheres is instantaneously cross-linked with the calcium ions in the solution to form an outer layer gel film. In this process, the Chinese medicine mixture and the thermosensitive polymer are evenly coated to form a dual drug loading system. The outer layer network has pH sensitivity and temperature sensitivity, and the inner layer network has pH sensitivity. The drug components therein can be released in layers, thereby reducing drug loss, prolonging the action time in the nasal cavity, and effectively improving bioavailability. The microspheres are collected and washed with deionized water to obtain dual-sensitive dual-network drug-loaded gel microspheres;

[0016] Preferably, in step (4), the amount of lactoferrin added is 0.6-0.8 g. Lactoferrin can convert the negatively charged Chinese medicine extract into a positive charge, which is conducive to better contact and reaction with the negatively charged nasal mucosa;

[0017] Preferably, in step (5), in the calcium chloride solution, the mass fraction of calcium chloride is 2.0-3.0%, and the mass fraction of the thermosensitive polymer is 1.0-2.0%. The addition of the thermosensitive polymer allows the outer layer of gel film to further condense at 35-37°C to release the first layer of drug components.

[0018] The present invention also provides a method for preparing a nasal gel for treating allergic rhinitis, which specifically comprises the following steps:

[0019] S1. Place the silkworm cocoon in 80 mL of 0.5% sodium carbonate solution, heat and boil in a water bath for 30 min, wash thoroughly with deionized water, dry, weigh 4-6 g of the obtained silk fibroin fiber and dissolve it in 100 mL of 50% lithium bromide solution until it is completely dissolved, centrifuge, take the upper layer, transfer it to a dialysis bag, and dialyze it with deionized water and ultrapure water for 1-3 days. Silk fibroin has biocompatibility and biodegradability, and has high cell adhesion, low antigenicity, and excellent mechanical properties. It can be used in nasal drug release systems to enhance adhesion in the nasal cavity to obtain a silk fibroin solution;

[0020] S2, 1.0-2.0g carboxymethyl chitosan and 0.5-1.0g K-carrageenan are mixed evenly, dissolved in 100-200mL deionized water, stirred evenly, 100mL of the silk fibroin solution described in step S1 is added dropwise, stirring is continued, and genipin is added to carry out a cross-linking reaction for 1-2h. The formed thermosensitive gel can maintain a moist environment and can also be quickly transformed into a gel at the nasal temperature to adhere to the nasal cilia, thereby increasing the residence time of the drug in the nasal cavity. The flexible addition of silk fibroin can reduce the damage to the nasal mucosa caused by the excessive strength of the gel material, thereby obtaining a thermosensitive gel material;

[0021] S3, adding the dual-sensitive dual-network drug-loaded gel microspheres to the thermosensitive gel material described in step S2, and uniformly dispersing them by ultrasound, with an ultrasound power of 500-600W and an ultrasound time of 20-30min. The dual-sensitive dual-network drug-loaded gel microspheres are distributed on the thermosensitive gel material. When the thermosensitive gel material is gelled, the dual-sensitive dual-network drug-loaded gel microspheres begin to function, and the outer network releases the first layer of drugs through temperature and pH, and the coagulation of the outer network further strengthens the fixation of the microspheres in the thermosensitive gel material, reduces the removal effect of nasal cilia on them, and is conducive to the inner network to continue to release the second layer of drugs, thereby achieving orderly release of drugs in the nasal cavity, increasing the action time of the drugs in the nasal mucosa, and significantly improving the bioavailability of the drugs, thereby obtaining a nasal gel for treating allergic rhinitis;

[0022] Preferably, in step S1, the mass fraction of silk fibroin in the solution is 3.0-5.0%, and silk fibroin can inhibit inflammatory response, promote the repair and regeneration of nasal mucosa, and alleviate discomfort symptoms in the nasal cavity;

[0023] Preferably, in step S2, the amount of genipin added is 1.0-1.5 g, which improves the stability of the thermosensitive gel material.

[0024] The beneficial effects achieved by the present invention are as follows:

[0025] The present invention loads dual-sensitive dual-network drug-loaded gel microspheres in a thermosensitive gel material. After entering the nasal cavity, the thermosensitive gel material quickly turns into a gel and adheres to the nasal cilia, reducing the removal of the dual-sensitive dual-network drug-loaded gel microspheres by the movement of the nasal cilia, which is conducive to the gel microspheres to better release the double-layer drug-loaded system, increasing the action time of the drug in the nasal cavity, significantly improving the bioavailability of the drug, effectively treating allergic rhinitis and alleviating discomfort symptoms; in the dual-sensitive dual-network drug-loaded gel microspheres, a dual-network double-layer drug-loaded microsphere structure is formed, the outer network has pH sensitivity and temperature sensitivity, the inner network has pH sensitivity, and the drug components therein can be released in layers to reduce the loss of the drug. The drug contained therein is a traditional Chinese medicine substance modified by lactoferrin. The introduction of positive charges is conducive to the traditional Chinese medicine substance to better contact with the negatively charged nasal mucosa and fully act on the diseased part. In addition, the double-layer network structure is conducive to respectively supporting and protecting the stability of the inner and outer structures, and is conducive to better responding to temperature and pH to release the drug; the thermosensitive gel In the material, a gel structure is formed, which can not only maintain a moist environment in the nasal cavity, but also softly adhere to the nasal cilia when gelling occurs, and at the same time loads dual-sensitive dual-network drug-loaded gel microspheres, so that the gel microspheres, the thermosensitive gel material and the nasal cilia or the nasal mucosa can all achieve mutual adhesion, effectively reducing the risk of being removed and moved, wherein the antibacterial property of carboxymethyl chitosan and L-carrageenan is also beneficial to alleviate the discomfort symptoms of allergic rhinitis; the addition of dual-sensitive dual-network drug-loaded gel microspheres improves the stability and bioadhesion of the thermosensitive gel material, can fully adhere to the nasal cilia, and increase the action time of the drug in the nasal cavity, while the thermosensitive gel material also reduces the sudden release of the drug in the microspheres, increases the difficulty of the microspheres moving, and provides a stable basis for the microspheres to play a role; the present invention uses dual-sensitive dual-network drug-loaded gel microspheres and thermosensitive gel materials to make a nasal gel for treating allergic rhinitis, effectively increases the action time of the drug in the nasal cavity, improves the bioavailability, and improves the therapeutic effectiveness of allergic rhinitis. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a scanning electron microscope image of the dual-sensitive dual-network drug-loaded gel microspheres prepared in Example 1 of the present invention;

[0027] Figure 2 This is a scanning electron microscope image of the temperature-sensitive gel material prepared in Example 1 of the present invention;

[0028] Figure 3 The bioadhesion results of Examples 1-4 and Comparative Examples 1-3 of the present invention are shown in FIG.

[0029] Figure 4 The swelling ratio results of Examples 1-4 and Comparative Examples 1-3 of the present invention are shown in FIG.

[0030] Figure 5 The graph shows the therapeutic efficacy results of Examples 1-4 and Comparative Examples 1-3 of the present invention. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0032] Unless otherwise defined, all professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to those described herein may be applied to the present invention. The preferred implementation methods and materials described herein are for demonstration purposes only and are not intended to limit the content of this application.

[0033] The experimental methods in the following examples are conventional methods unless otherwise specified; the experimental materials used in the following examples are purchased from commercial channels unless otherwise specified.

[0034] The sources of the reagents used in the examples are as follows:

[0035] Nanocrystalline cellulose CAS No: 9004-34-6, brand Innochem, product number A00472;

[0036] THF CAS No: 109-99-9, brand Innochem, product number A06439;

[0037] Triethylamine CAS No: 121-44-8, brand Innochem, product number A49708;

[0038] 4-Dimethylaminopyridine CAS No: 1122-58-3, brand Innochem, product number A11182;

[0039] Sodium alginate CAS No: 9005-38-3, brand Innochem, product number A02570;

[0040] Calcium chloride CAS No: 10043-52-4, brand Innochem, product number A06389;

[0041] 2-Bromoisobutyryl bromide CAS No: 20769-85-1, brand Innochem, product number A75059;

[0042] Acetone CAS No: 67-64-1, brand Acros, product number 177170010;

[0043] Cuprous bromide CAS No: 7787-70-4, brand Innochem, product number A50570;

[0044] Glacial acetic acid CAS No: 64-19-7, brand Innochem, product number A11557;

[0045] Methanol CAS No: 67-56-1, brand Innochem, product number A45780;

[0046] N-isopropylacrylamide CAS No: 2210-25-5, brand Innochem, product number A49861;

[0047] N,N,N',N',N''-pentamethyldiethyltriamine CASNo:3030-47-5, brand Sigma-aldrich, product number 369497-250ML;

[0048] Lactoferrin CAS No: 112163-33-4, brand Macklin, product number J902427-1g;

[0049] Sodium carbonate CAS No: 497-19-8, brand Innochem, product number A19943;

[0050] Carboxymethyl chitosan CAS No: 83512-85-0, brand Macklin, product number C804727-5g;

[0051] K-carrageenan CAS No: 11114-20-8, brand Innochem, product number A87236;

[0052] Genipin CAS No: 6902-77-8, brand Innochem, product number A05406;

[0053] Anhydrous ethanol CAS No: 64-17-5, brand Innochem, product number G00004.

[0054] Example 1

[0055] This embodiment provides a nasal gel for treating allergic rhinitis, comprising the following components in parts by weight: 30 parts of dual-sensitive dual-network drug-loaded gel microspheres and 20 parts of thermosensitive gel material.

[0056] The double-sensitive double-network drug-loaded gel microspheres include the following components in parts by weight: 20 parts of sodium alginate, 5 parts of thermosensitive polymer, 4 parts of lactoferrin, 12 parts of traditional Chinese medicine extract, and 15 parts of calcium chloride.

[0057] The thermosensitive gel material comprises the following components in parts by weight: 50 parts of silk fibroin, 20 parts of carboxymethyl chitosan, 10 parts of K-carrageenan and 15 parts of genipin.

[0058] The raw materials of the Chinese medicine extract include the following components in parts by weight: 5 parts of platycodon, 5 parts of astragalus, 5 parts of atractylodes, 5 parts of tangerine peel, 5 parts of xanthium sibiricum, 5 parts of magnolia, 5 parts of angelica dahurica and 5 parts of liquorice.

[0059] The preparation method of dual-sensitive dual-network drug-loaded gel microspheres specifically comprises the following steps:

[0060] (1) Grind Platycodon grandiflorum, Astragalus membranaceus, Atractylodes macrocephala, Tangerine peel, Xanthium sibiricum, Magnolia officinalis, Angelica dahurica and Licorice root, pass through an 80-mesh sieve, mix evenly, add 4 times the amount of distilled water and boil for 3 times, filter while hot, combine the filtrate, and concentrate to 1 / 5 of the original volume of the filtrate, select Chinese medicinal materials that dispel wind and relieve exterior symptoms and clear the nasal passages, and then use them in combination with medicinal materials that replenish qi and strengthen the exterior and improve immunity to assist in the treatment of allergic rhinitis and effectively relieve symptoms such as nasal congestion, nasal flow, sneezing, and nasal itching, to obtain a Chinese medicinal extract;

[0061] (2) 50 mL of a nanocrystalline cellulose aqueous suspension with a solid content of 1 g was replaced with anhydrous THF by a solvent replacement method, transferred to a round-bottom flask, and 1.8 g of triethylamine and 1.5 g of 4-dimethylaminopyridine were added. The mixture was stirred evenly by magnetic stirring. The obtained mixed solution was set aside. 5.5 g of 2-bromoisobutyryl bromide was dissolved in 50 mL of anhydrous THF in advance and slowly added to the mixed solution through a constant pressure funnel in nitrogen. After the addition was complete, the bottle mouth was sealed and stirred magnetically at room temperature for 24 h. The product was washed 5 times with anhydrous THF, an equal volume mixture of anhydrous THF and anhydrous ethanol, and acetone. By using 2-bromoisobutyryl bromide to initiate bromination of nanocrystalline cellulose in an anhydrous THF environment, it presented a rod-like structure, which could increase the contact with nasal cilia and reduce removal, thereby obtaining modified nanocrystalline cellulose.

[0062] (3) 0.2 g of cuprous bromide was placed in a reaction bottle, and washed with glacial acetic acid, anhydrous ethanol, and methanol for several times until the cuprous bromide turned light yellow. 300 mg of the modified nanocrystalline cellulose described in step (2), 11.0 g of recrystallized N-isopropylacrylamide, and 50 mL of methanol solution were added. The mixture was stirred magnetically, and the bottle mouth was sealed. The mixed solution was frozen and thawed several times by liquid nitrogen freeze-thaw method to remove oxygen to the maximum extent. After the mixture was warmed up, 0.2 mL of N,N,N',N',N''-pentamethyldiethyltriamine was added to the freeze-thaw solution through a syringe. The mixture was stirred magnetically at room temperature for 24 h. The reaction product was washed with methanol and anhydrous ethanol for 5 times. The copolymerization and grafting of N-isopropylacrylamide on the modified nanocrystalline cellulose was achieved, which broadened the application range of thermosensitive materials and obtained thermosensitive polymers.

[0063] (4) Adding lactoferrin to the Chinese medicine extract described in step (1), the amount of lactoferrin added is 0.8 g. Lactoferrin can convert the negatively charged Chinese medicine extract into a positive charge, which is conducive to better contact and reaction with the negatively charged nasal mucosa. The mixture is magnetically stirred for 6 hours, 1 / 2 of the Chinese medicine mixture is mixed with 50 mL of a 4.0% sodium alginate solution, and added to 50 mL of a 3.0% calcium chloride solution through a microinjection pump. The product is collected. The gel microspheres are coated with drugs and are not easily removed by the movement of nasal cilia. They can adhere to the nasal cilia and release the drug components through pH responsiveness in the nasal cavity, thereby increasing the action time in the nasal cavity and reducing the number of administrations, thereby obtaining inner-layer drug-loaded gel microspheres;

[0064] (5) The remaining 1 / 2 amount of the Chinese medicine mixture is mixed with 50 mL of a sodium alginate solution with a mass fraction of 4.0%, and the inner layer drug-loaded gel microspheres described in step (4) are placed in the solution for adsorption for 2 hours. The solution is taken out and then transferred to 50 mL of a calcium chloride solution containing the thermosensitive polymer described in step (3) for sufficient reaction for 3 hours. The mass fraction of calcium chloride in the calcium chloride solution is 3.0%, and the mass fraction of the thermosensitive polymer is 2.0%. The addition of the thermosensitive polymer allows the outer layer gel film to further condense at 35-37°C, releasing the first layer of drug components. The sodium alginate adsorbed on the surface of the microspheres is instantaneously cross-linked with the calcium ions in the solution to form an outer layer gel film. In the process, the Chinese medicine mixture and the thermosensitive polymer are uniformly coated to form a dual drug loading system. The outer layer network has pH sensitivity and temperature sensitivity, and the inner layer network has pH sensitivity. The drug components therein can be released in layers, reducing drug loss, prolonging the action time in the nasal cavity, and effectively improving bioavailability. The microspheres are collected and washed with deionized water to obtain dual-sensitive dual-network drug-loaded gel microspheres.

[0065] This embodiment provides a method for preparing a nasal gel for treating allergic rhinitis, which specifically comprises the following steps:

[0066] S1. Place the silkworm cocoon in 80 mL of 0.5% sodium carbonate solution, heat and boil in a water bath for 30 min, wash thoroughly with deionized water, dry, weigh 6.0 g of the obtained silk fibroin fiber and dissolve it in 100 mL of 50% lithium bromide solution until it is completely dissolved, centrifuge, take the upper layer, transfer it to a dialysis bag, dialyze with deionized water and ultrapure water for 3 days, the mass fraction of silk fibroin in the solution is 5.0%, silk fibroin can inhibit inflammatory response, promote the repair and regeneration of nasal mucosa, and alleviate the discomfort symptoms in the nasal cavity. Silk fibroin has biocompatibility and biodegradability, and has high cell adhesion, low antigenicity, and excellent mechanical properties. It can be used in nasal drug release systems to enhance adhesion in the nasal cavity to obtain a silk fibroin solution;

[0067] S2, 2.0g carboxymethyl chitosan and 1.0g K-carrageenan were mixed evenly, dissolved in 200mL deionized water, stirred evenly, 100mL of the silk fibroin solution described in step S1 was added dropwise, stirring was continued, and genipin was added to carry out cross-linking reaction for 2h. The formed thermosensitive gel can maintain a moist environment and can also be quickly transformed into a gel at nasal temperature and adhere to the nasal cilia, thereby increasing the residence time of the drug in the nasal cavity. The amount of genipin added was 1.5g, which improved the stability of the thermosensitive gel material. The flexible addition of silk fibroin can reduce the damage to the nasal mucosa caused by excessive strength of the gel material, thereby obtaining a thermosensitive gel material;

[0068] S3. Add the dual-sensitive dual-network drug-loaded gel microspheres to the thermosensitive gel material described in step S2, and disperse them evenly by ultrasound. The ultrasonic power is 600 W and the ultrasonic time is 30 min. The dual-sensitive dual-network drug-loaded gel microspheres are distributed on the thermosensitive gel material. When the thermosensitive gel material is gelled, the dual-sensitive dual-network drug-loaded gel microspheres begin to play a role. The outer network releases the first layer of drugs through temperature and pH, and the coagulation of the outer network further strengthens the fixation of the microspheres in the thermosensitive gel material, reduces the removal effect of nasal cilia on them, and is conducive to the inner network to continue to release the second layer of drugs, thereby achieving orderly release of drugs in the nasal cavity, increasing the action time of drugs in the nasal mucosa, and significantly improving the bioavailability of drugs, thereby obtaining a nasal gel for treating allergic rhinitis.

[0069] In this example, the prepared dual-sensitive dual-network drug-loaded gel microspheres and thermosensitive gel materials were subjected to scanning electron microscopy to observe their microscopic morphology. Figure 1 This is a 100-fold magnified SEM image of the dual-sensitive dual-network drug-loaded gel microspheres prepared in Example 1. Figure 2 This is a SEM image of the thermosensitive gel material prepared in Example 1 magnified 200 times, as shown Figure 1 The dual-sensitive dual-network drug-loaded gel microspheres prepared in this embodiment present a dual-network microsphere structure, such as Figure 2The temperature-sensitive gel material prepared in this embodiment is a flexible gel structure.

[0070] Example 2

[0071] This embodiment provides a nasal gel for treating allergic rhinitis, comprising the following components in parts by weight: 20 parts of dual-sensitive dual-network drug-loaded gel microspheres and 10 parts of thermosensitive gel material.

[0072] The double-sensitive double-network drug-loaded gel microspheres include the following components in parts by weight: 15 parts of sodium alginate, 2.5 parts of thermosensitive polymer, 3 parts of lactoferrin, 9 parts of traditional Chinese medicine extract, and 10 parts of calcium chloride.

[0073] The thermosensitive gel material comprises the following components in parts by weight: 30 parts of silk fibroin, 10 parts of carboxymethyl chitosan, 5 parts of K-carrageenan and 10 parts of genipin.

[0074] The raw materials of the Chinese medicine extract include the following components in parts by weight: 3 parts of platycodon, 3 parts of astragalus, 3 parts of atractylodes, 3 parts of tangerine peel, 3 parts of xanthium, 3 parts of magnolia, 3 parts of angelica, and 3 parts of liquorice.

[0075] The preparation method of dual-sensitive dual-network drug-loaded gel microspheres specifically comprises the following steps:

[0076] (1) Grind Platycodon grandiflorum, Astragalus membranaceus, Atractylodes macrocephala, Tangerine peel, Xanthium sibiricum, Magnolia officinalis, Angelica dahurica and Licorice root, pass through a 60-mesh sieve, mix evenly, add 4 times the amount of distilled water and boil twice, filter while hot, combine the filtrate, and concentrate to 1 / 4 of the original volume of the filtrate, select Chinese medicinal materials that dispel wind and relieve exterior symptoms and clear the nasal passages, and then use them in combination with medicinal materials that replenish qi and strengthen the exterior and improve immunity to assist in the treatment of allergic rhinitis and effectively relieve symptoms such as nasal congestion, nasal flow, sneezing, and nasal itching, to obtain a Chinese medicinal extract;

[0077] (2) 30 mL of a nanocrystalline cellulose aqueous suspension with a solid content of 1 g was replaced with anhydrous THF by a solvent replacement method, transferred to a round-bottom flask, and 1.8 g of triethylamine and 1.5 g of 4-dimethylaminopyridine were added. The mixture was stirred evenly by magnetic stirring. The obtained mixed solution was set aside. 5.5 g of 2-bromoisobutyryl bromide was dissolved in 30 mL of anhydrous THF in advance and slowly added to the mixed solution through a constant pressure funnel in nitrogen. After the addition was complete, the bottle mouth was sealed and stirred magnetically at room temperature for 24 h. The product was washed three times with anhydrous THF, an equal volume mixture of anhydrous THF and anhydrous ethanol, and acetone. By using 2-bromoisobutyryl bromide to initiate bromination of nanocrystalline cellulose in an anhydrous THF environment, it presented a rod-like structure, which could increase the contact with nasal cilia and reduce removal, thereby obtaining modified nanocrystalline cellulose.

[0078] (3) 0.2 g of cuprous bromide was placed in a reaction bottle, and washed with glacial acetic acid, anhydrous ethanol, and methanol for several times until the cuprous bromide turned light yellow. 300 mg of the modified nanocrystalline cellulose described in step (2), 11.0 g of recrystallized N-isopropylacrylamide, and 30 mL of methanol solution were added. The mixture was stirred magnetically, and the bottle mouth was sealed. The mixed solution was frozen and thawed several times by liquid nitrogen freeze-thaw method to remove oxygen to the maximum extent. After the mixture was warmed up, 0.2 mL of N,N,N',N',N''-pentamethyldiethyltriamine was added to the freeze-thaw solution through a syringe. The mixture was stirred magnetically at room temperature for 24 h. The reaction product was washed with methanol and anhydrous ethanol for three times. The copolymerization and grafting of N-isopropylacrylamide on the modified nanocrystalline cellulose was achieved, which broadened the application range of thermosensitive materials and obtained thermosensitive polymers.

[0079] (4) Adding lactoferrin to the Chinese medicine extract described in step (1), the amount of lactoferrin added is 0.6 g. Lactoferrin can convert the negatively charged Chinese medicine extract into a positive charge, which is conducive to better contact and reaction with the negatively charged nasal mucosa. Stirring magnetically for 5 hours, taking 1 / 2 of the Chinese medicine mixture and mixing it with 50 mL of a 3.0% sodium alginate solution, adding it to 50 mL of a 2.0% calcium chloride solution through a microinjection pump, collecting the product, the gel microspheres coated with drugs are not easily removed by the movement of nasal cilia, and can adhere to the nasal cilia to release the drug components through pH responsiveness in the nasal cavity, thereby increasing the action time in the nasal cavity and reducing the number of administrations, thereby obtaining inner layer drug-loaded gel microspheres;

[0080] (5) The remaining 1 / 2 amount of the Chinese medicine mixture is mixed with 50 mL of a 3.0% sodium alginate solution, and the inner layer drug-loaded gel microspheres described in step (4) are placed in the solution for adsorption for 1 hour, taken out, and then transferred to 50 mL of a calcium chloride solution containing the thermosensitive polymer described in step (3) for sufficient reaction for 2 hours. The mass fraction of calcium chloride in the calcium chloride solution is 2.0%, and the mass fraction of the thermosensitive polymer is 1.0%. The addition of the thermosensitive polymer allows the outer layer gel film to further condense at 35-37°C, releasing the first layer of drug components. The sodium alginate adsorbed on the surface of the microspheres is instantaneously cross-linked with the calcium ions in the solution to form an outer layer gel film. In the process, the Chinese medicine mixture and the thermosensitive polymer are uniformly coated to form a dual drug loading system. The outer layer network has pH sensitivity and temperature sensitivity, and the inner layer network has pH sensitivity. The drug components therein can be released in layers, reducing drug loss, prolonging the action time in the nasal cavity, and effectively improving bioavailability. The microspheres are collected and washed with deionized water to obtain dual-sensitive dual-network drug-loaded gel microspheres.

[0081] This embodiment provides a method for preparing a nasal gel for treating allergic rhinitis, which specifically comprises the following steps:

[0082] S1. Place the silkworm cocoon in 80 mL of 0.5% sodium carbonate solution, heat and boil in a water bath for 30 min, wash thoroughly with deionized water, dry, weigh 4.0 g of the obtained silk fibroin fiber and dissolve it in 100 mL of 50% lithium bromide solution until it is completely dissolved, centrifuge, take the upper layer, transfer it to a dialysis bag, dialyze with deionized water and ultrapure water for 1 day, the mass fraction of silk fibroin in the solution is 3.0%, silk fibroin can inhibit inflammatory response, promote the repair and regeneration of nasal mucosa, and alleviate the discomfort symptoms in the nasal cavity. Silk fibroin has biocompatibility and biodegradability, and has high cell adhesion, low antigenicity, and excellent mechanical properties. It can be used in nasal drug release systems to enhance adhesion in the nasal cavity to obtain a silk fibroin solution;

[0083] S2, 1.0g carboxymethyl chitosan and 0.5g K-carrageenan were mixed evenly, dissolved in 100mL deionized water, stirred evenly, 100mL of the silk fibroin solution described in step S1 was added dropwise, stirring was continued, and genipin was added to carry out a cross-linking reaction for 1h. The formed thermosensitive gel can maintain a moist environment and can also be quickly transformed into a gel at nasal temperature and adhere to the nasal cilia, thereby increasing the residence time of the drug in the nasal cavity. The amount of genipin added was 1.0g, which improved the stability of the thermosensitive gel material. The flexible addition of silk fibroin can reduce the damage of the nasal mucosa to the nasal mucosa due to excessive strength of the gel material, thereby obtaining a thermosensitive gel material;

[0084] S3. Add the dual-sensitive dual-network drug-loaded gel microspheres to the thermosensitive gel material described in step S2, and disperse them evenly by ultrasound. The ultrasonic power is 500 W and the ultrasonic time is 20 min. The dual-sensitive dual-network drug-loaded gel microspheres are distributed on the thermosensitive gel material. When the thermosensitive gel material is gelled, the dual-sensitive dual-network drug-loaded gel microspheres begin to play a role. The outer network releases the first layer of drugs through temperature and pH, and the coagulation of the outer network further strengthens the fixation of the microspheres in the thermosensitive gel material, reduces the removal effect of nasal cilia on them, and is conducive to the inner network to continue to release the second layer of drugs, thereby achieving orderly release of drugs in the nasal cavity, increasing the action time of drugs in the nasal mucosa, and significantly improving the bioavailability of drugs, thereby obtaining a nasal gel for treating allergic rhinitis.

[0085] Example 3

[0086] This embodiment provides a nasal gel for treating allergic rhinitis, comprising the following components in parts by weight: 25 parts of dual-sensitive dual-network drug-loaded gel microspheres and 15 parts of thermosensitive gel material.

[0087] The double-sensitive double-network drug-loaded gel microspheres include the following components in parts by weight: 17.5 parts of sodium alginate, 3.75 parts of thermosensitive polymer, 3.5 parts of lactoferrin, 10.5 parts of traditional Chinese medicine extract, and 12.5 parts of calcium chloride.

[0088] The thermosensitive gel material comprises the following components in parts by weight: 40 parts of silk fibroin, 15 parts of carboxymethyl chitosan, 7.5 parts of K-carrageenan and 12.5 parts of genipin.

[0089] The raw materials of the Chinese medicine extract include the following components in parts by weight: 4 parts of platycodon, 4 parts of astragalus, 4 parts of atractylodes, 4 parts of tangerine peel, 4 parts of xanthium sibiricum, 4 parts of magnolia, 4 parts of angelica dahurica and 4 parts of liquorice.

[0090] The preparation method of dual-sensitive dual-network drug-loaded gel microspheres specifically comprises the following steps:

[0091] (1) Grind Platycodon grandiflorum, Astragalus membranaceus, Atractylodes macrocephala, Tangerine peel, Xanthium sibiricum, Magnolia officinalis, Angelica dahurica and Licorice root, pass through a 70-mesh sieve, mix evenly, add 4 times the amount of distilled water and boil twice, filter while hot, combine the filtrates, and concentrate to 1 / 5 of the original volume of the filtrate, select Chinese herbal medicines that dispel wind and relieve exterior symptoms and clear the nasal passages, and then use them in combination with herbal medicines that replenish qi and strengthen the exterior and improve immunity to assist in the treatment of allergic rhinitis and effectively relieve symptoms such as nasal congestion, nasal flow, sneezing, and nasal itching, to obtain a Chinese herbal medicine extract;

[0092] (2) 40 mL of a nanocrystalline cellulose aqueous suspension with a solid content of 1 g was replaced with anhydrous THF by a solvent replacement method, transferred to a round-bottom flask, and 1.8 g of triethylamine and 1.5 g of 4-dimethylaminopyridine were added. The mixture was stirred evenly by magnetic stirring. The obtained mixed solution was set aside. 5.5 g of 2-bromoisobutyryl bromide was dissolved in 40 mL of anhydrous THF in advance and slowly added to the mixed solution through a constant pressure funnel in nitrogen. After the addition was complete, the bottle mouth was sealed and magnetically stirred at room temperature for 24 h. The product was washed four times with anhydrous THF, an equal volume mixture of anhydrous THF and anhydrous ethanol, and acetone. By using 2-bromoisobutyryl bromide to initiate bromination of nanocrystalline cellulose in an anhydrous THF environment, it presented a rod-like structure, which could increase the contact with nasal cilia and reduce removal, thereby obtaining modified nanocrystalline cellulose.

[0093] (3) 0.2 g of cuprous bromide was placed in a reaction bottle, and washed with glacial acetic acid, anhydrous ethanol, and methanol for several times until the cuprous bromide turned light yellow. 300 mg of the modified nanocrystalline cellulose described in step (2), 11.0 g of recrystallized N-isopropylacrylamide, and 40 mL of methanol solution were added. The mixture was stirred magnetically, and the bottle mouth was sealed. The mixed solution was frozen and thawed several times by liquid nitrogen freeze-thaw method to remove oxygen to the maximum extent. After the mixture was warmed up, 0.2 mL of N,N,N',N',N''-pentamethyldiethyltriamine was added to the freeze-thaw solution through a syringe. The mixture was stirred magnetically at room temperature for 24 h. The reaction product was washed with methanol and anhydrous ethanol for 4 times. The copolymerization and grafting of N-isopropylacrylamide on the modified nanocrystalline cellulose was achieved, which broadened the application range of thermosensitive materials and obtained thermosensitive polymers.

[0094] (4) Adding lactoferrin to the Chinese medicine extract described in step (1), the amount of lactoferrin added is 0.7 g. Lactoferrin can convert the negatively charged Chinese medicine extract into a positive charge, which is conducive to better contact and reaction with the negatively charged nasal mucosa. The mixture is magnetically stirred for 5.5 hours, 1 / 2 of the Chinese medicine mixture is mixed with 50 mL of a 3.5% sodium alginate solution, and added to 50 mL of a 2.5% calcium chloride solution through a microinjection pump. The product is collected. The gel microspheres are coated with drugs and are not easily removed by the movement of nasal cilia. They can adhere to the nasal cilia and release the drug components through pH responsiveness in the nasal cavity, thereby increasing the action time in the nasal cavity and reducing the number of administrations, thereby obtaining inner-layer drug-loaded gel microspheres;

[0095] (5) The remaining 1 / 2 amount of the Chinese medicine mixture is mixed with 50 mL of a 3.5% sodium alginate solution, and the inner drug-loaded gel microspheres described in step (4) are placed therein for adsorption for 1.5 hours, taken out, and then transferred to 50 mL of a calcium chloride solution containing the thermosensitive polymer described in step (3) and fully reacted for 2.5 hours. In the calcium chloride solution, the mass fraction of calcium chloride is 2.5%, and the mass fraction of the thermosensitive polymer is 1.5%. The addition of the thermosensitive polymer allows the outer gel film to further solidify at 35-37°C. Polymerization, release the first layer of drug ingredients, and the sodium alginate adsorbed on the surface of the microspheres is instantaneously cross-linked with the calcium ions in the solution to form an outer gel film. In the process, the traditional Chinese medicine mixture and the thermosensitive polymer are evenly coated to form a dual drug loading system. The outer network is pH-sensitive and temperature-sensitive, and the inner network is pH-sensitive. The drug ingredients can be released in layers, reducing the loss of drugs, prolonging the action time in the nasal cavity, and effectively improving the bioavailability. The microspheres are collected and washed with deionized water to obtain dual-sensitive dual-network drug-loaded gel microspheres.

[0096] This embodiment provides a method for preparing a nasal gel for treating allergic rhinitis, which specifically comprises the following steps:

[0097] S1. Place the silkworm cocoon in 80 mL of 0.5% sodium carbonate solution, heat and boil in a water bath for 30 min, wash thoroughly with deionized water, dry, weigh 5.0 g of the obtained silk fibroin fiber and dissolve it in 100 mL of 50% lithium bromide solution until it is completely dissolved, centrifuge, take the upper layer, transfer it to a dialysis bag, dialyze with deionized water and ultrapure water for 2 days, the mass fraction of silk fibroin in the solution is 4.0%, silk fibroin can inhibit inflammatory response, promote the repair and regeneration of nasal mucosa, and alleviate the discomfort symptoms in the nasal cavity. Silk fibroin has biocompatibility and biodegradability, and has high cell adhesion, low antigenicity, and excellent mechanical properties. It can be used in nasal drug release systems to enhance adhesion in the nasal cavity to obtain a silk fibroin solution;

[0098] S2, 1.5g carboxymethyl chitosan and 0.75g K-carrageenan were mixed evenly, dissolved in 150mL deionized water, stirred evenly, 100mL of the silk fibroin solution described in step S1 was added dropwise, stirring was continued, and genipin was added to carry out cross-linking reaction for 1.5h. The formed thermosensitive gel can maintain a moist environment and can also be quickly transformed into a gel at nasal temperature and adhere to the nasal cilia, thereby increasing the residence time of the drug in the nasal cavity. The amount of genipin added was 1.25g, which improved the stability of the thermosensitive gel material. The flexible addition of silk fibroin can reduce the damage of the gel material to the nasal mucosa due to excessive strength, thereby obtaining a thermosensitive gel material;

[0099] S3. Add the dual-sensitive dual-network drug-loaded gel microspheres to the thermosensitive gel material described in step S2, and disperse them evenly by ultrasound. The ultrasonic power is 550 W and the ultrasonic time is 25 min. The dual-sensitive dual-network drug-loaded gel microspheres are distributed on the thermosensitive gel material. When the thermosensitive gel material is gelled, the dual-sensitive dual-network drug-loaded gel microspheres begin to play a role. The outer network releases the first layer of drugs through temperature and pH, and the coagulation of the outer network further strengthens the fixation of the microspheres in the thermosensitive gel material, reduces the removal effect of nasal cilia on them, and is conducive to the inner network to continue to release the second layer of drugs, thereby achieving orderly release of drugs in the nasal cavity, increasing the action time of drugs in the nasal mucosa, and significantly improving the bioavailability of drugs, thereby obtaining a nasal gel for treating allergic rhinitis.

[0100] Example 4

[0101] This embodiment provides a nasal gel for treating allergic rhinitis, comprising the following components in parts by weight: 20 parts of dual-sensitive dual-network drug-loaded gel microspheres and 20 parts of thermosensitive gel material.

[0102] The double-sensitive double-network drug-loaded gel microspheres include the following components in parts by weight: 20 parts of sodium alginate, 2.5 parts of thermosensitive polymer, 3 parts of lactoferrin, 12 parts of traditional Chinese medicine extract, and 15 parts of calcium chloride.

[0103] The thermosensitive gel material comprises the following components in parts by weight: 30 parts of silk fibroin, 20 parts of carboxymethyl chitosan, 10 parts of K-carrageenan and 10 parts of genipin.

[0104] The raw materials of the Chinese medicine extract include the following components in parts by weight: 5 parts of platycodon, 5 parts of astragalus, 5 parts of atractylodes, 5 parts of tangerine peel, 5 parts of xanthium sibiricum, 5 parts of magnolia, 5 parts of angelica dahurica and 5 parts of liquorice.

[0105] The preparation method of dual-sensitive dual-network drug-loaded gel microspheres specifically comprises the following steps:

[0106] (1) Grind Platycodon grandiflorum, Astragalus membranaceus, Atractylodes macrocephala, Tangerine peel, Xanthium sibiricum, Magnolia officinalis, Angelica dahurica and Licorice root, pass through an 80-mesh sieve, mix evenly, add 4 times the amount of distilled water and boil for 3 times, filter while hot, combine the filtrates, and concentrate to 1 / 4 of the original volume of the filtrate, select Chinese medicinal materials that dispel wind and relieve exterior symptoms and clear the nasal passages, and then use them in combination with medicinal materials that replenish qi and strengthen the exterior and improve immunity to assist in the treatment of allergic rhinitis and effectively relieve symptoms such as nasal congestion, nasal flow, sneezing, and nasal itching, to obtain a Chinese medicinal extract;

[0107] (2) 50 mL of a nanocrystalline cellulose aqueous suspension with a solid content of 1 g was replaced with anhydrous THF by a solvent replacement method, transferred to a round-bottom flask, and 1.8 g of triethylamine and 1.5 g of 4-dimethylaminopyridine were added. The mixture was stirred evenly by magnetic stirring. The obtained mixed solution was set aside. 5.5 g of 2-bromoisobutyryl bromide was dissolved in 50 mL of anhydrous THF in advance and slowly added to the mixed solution through a constant pressure funnel in nitrogen. After the addition was complete, the bottle mouth was sealed and stirred magnetically at room temperature for 24 h. The product was washed five times with anhydrous THF, an equal volume mixture of anhydrous THF and anhydrous ethanol, and acetone. By using 2-bromoisobutyryl bromide to initiate bromination of nanocrystalline cellulose in an anhydrous THF environment, it presented a rod-like structure, which could increase the contact with nasal cilia and reduce removal, thereby obtaining modified nanocrystalline cellulose.

[0108] (3) 0.2 g of cuprous bromide was placed in a reaction bottle, and washed with glacial acetic acid, anhydrous ethanol, and methanol for several times until the cuprous bromide turned light yellow. 300 mg of the modified nanocrystalline cellulose described in step (2), 11.0 g of recrystallized N-isopropylacrylamide, and 50 mL of methanol solution were added. The mixture was stirred magnetically, and the bottle mouth was sealed. The mixed solution was frozen and thawed several times by liquid nitrogen freeze-thaw method to remove oxygen to the maximum extent. After the mixture was warmed up, 0.2 mL of N,N,N',N',N''-pentamethyldiethyltriamine was added to the freeze-thaw solution through a syringe. The mixture was stirred magnetically at room temperature for 24 h. The reaction product was washed with methanol and anhydrous ethanol for 5 times. The copolymerization and grafting of N-isopropylacrylamide on the modified nanocrystalline cellulose was achieved, which broadened the application range of thermosensitive materials and obtained thermosensitive polymers.

[0109] (4) Adding lactoferrin to the Chinese medicine extract described in step (1), the amount of lactoferrin added is 0.6 g. Lactoferrin can convert the negatively charged Chinese medicine extract into a positive charge, which is conducive to better contact and reaction with the negatively charged nasal mucosa. Stirring magnetically for 5 hours, taking 1 / 2 of the Chinese medicine mixture and mixing it with 50 mL of a 4.0% sodium alginate solution, adding it to 50 mL of a 3.0% calcium chloride solution through a microinjection pump, collecting the product, the gel microspheres coated with drugs are not easily removed by the movement of nasal cilia, and can adhere to the nasal cilia to release the drug components through pH responsiveness in the nasal cavity, thereby increasing the action time in the nasal cavity and reducing the number of administrations, thereby obtaining inner layer drug-loaded gel microspheres;

[0110] (5) The remaining 1 / 2 amount of the Chinese medicine mixture is mixed with 50 mL of a sodium alginate solution with a mass fraction of 4.0%, and the inner layer drug-loaded gel microspheres described in step (4) are placed in the solution for adsorption for 1 hour, taken out, and then transferred to 50 mL of a calcium chloride solution containing the thermosensitive polymer described in step (3) for sufficient reaction for 2 hours. In the calcium chloride solution, the mass fraction of calcium chloride is 3.0%, and the mass fraction of the thermosensitive polymer is 1.0%. The addition of the thermosensitive polymer allows the outer layer gel film to further condense at 35-37°C, releasing the first layer of drug components. The sodium alginate adsorbed on the surface of the microspheres is instantaneously cross-linked with the calcium ions in the solution to form an outer layer gel film. In the process, the Chinese medicine mixture and the thermosensitive polymer are uniformly coated to form a dual drug loading system. The outer layer network has pH sensitivity and temperature sensitivity, and the inner layer network has pH sensitivity. The drug components therein can be released in layers, reducing drug loss, prolonging the action time in the nasal cavity, and effectively improving bioavailability. The microspheres are collected and washed with deionized water to obtain dual-sensitive dual-network drug-loaded gel microspheres.

[0111] This embodiment provides a method for preparing a nasal gel for treating allergic rhinitis, which specifically comprises the following steps:

[0112] S1. Place the silkworm cocoon in 80 mL of 0.5% sodium carbonate solution, heat and boil in a water bath for 30 min, wash thoroughly with deionized water, dry, weigh 4.0 g of the obtained silk fibroin fiber and dissolve it in 100 mL of 50% lithium bromide solution until it is completely dissolved, centrifuge, take the upper layer, transfer it to a dialysis bag, dialyze with deionized water and ultrapure water for 1 day, the mass fraction of silk fibroin in the solution is 3.0%, silk fibroin can inhibit inflammatory response, promote the repair and regeneration of nasal mucosa, and alleviate the discomfort symptoms in the nasal cavity. Silk fibroin has biocompatibility and biodegradability, and has high cell adhesion, low antigenicity, and excellent mechanical properties. It can be used in nasal drug release systems to enhance adhesion in the nasal cavity to obtain a silk fibroin solution;

[0113] S2, 2.0g carboxymethyl chitosan and 1.0g K-carrageenan were mixed evenly, dissolved in 200mL deionized water, stirred evenly, 100mL of the silk fibroin solution described in step S1 was added dropwise, stirring was continued, and genipin was added to carry out a cross-linking reaction for 1h. The formed thermosensitive gel can maintain a moist environment and can also be quickly transformed into a gel at nasal temperature to adhere to the nasal cilia, thereby increasing the residence time of the drug in the nasal cavity. The amount of genipin added was 1.0g, which improved the stability of the thermosensitive gel material. The flexible addition of silk fibroin can reduce the damage to the nasal mucosa caused by excessive strength of the gel material, thereby obtaining a thermosensitive gel material;

[0114] S3. Add the dual-sensitive dual-network drug-loaded gel microspheres to the thermosensitive gel material described in step S2, and disperse them evenly by ultrasound. The ultrasonic power is 600 W and the ultrasonic time is 20 min. The dual-sensitive dual-network drug-loaded gel microspheres are distributed on the thermosensitive gel material. When the thermosensitive gel material is gelled, the dual-sensitive dual-network drug-loaded gel microspheres begin to play a role. The outer network releases the first layer of drugs through temperature and pH, and the coagulation of the outer network further strengthens the fixation of the microspheres in the thermosensitive gel material, reduces the removal effect of nasal cilia on them, and is conducive to the inner network to continue to release the second layer of drugs, thereby achieving orderly release of drugs in the nasal cavity, increasing the action time of drugs in the nasal mucosa, and significantly improving the bioavailability of drugs, thereby obtaining a nasal gel for treating allergic rhinitis.

[0115] Comparative Example 1

[0116] This comparative example provides a nasal gel for treating allergic rhinitis, which differs from Example 1 in that the nasal gel for treating allergic rhinitis does not contain a thermosensitive gel material; the preparation method of the dual-sensitive dual-network drug-loaded gel microspheres is the same as that of Example 1; the preparation method of the nasal gel for treating allergic rhinitis does not include steps S1 and S2.

[0117] Comparative Example 2

[0118] This comparative example provides a nasal gel for treating allergic rhinitis, which differs from Example 1 in that the dual-sensitive dual-network drug-loaded gel microspheres do not contain a thermosensitive polymer and an outer network structure; the preparation method of the dual-sensitive dual-network drug-loaded gel microspheres does not include step (5); and the preparation method of the nasal gel for treating allergic rhinitis is the same as that of Example 1.

[0119] Comparative Example 3

[0120] This comparative example provides a nasal gel for treating allergic rhinitis, which differs from Example 1 in that the dual-sensitive dual-network drug-loaded gel microspheres do not contain lactoferrin and an inner network structure; the preparation method of the dual-sensitive dual-network drug-loaded gel microspheres does not include step (4); and the preparation method of the nasal gel for treating allergic rhinitis is the same as that of Example 1.

[0121] Experimental Example 1

[0122] Bioadhesion test

[0123] Test samples: nasal gels for treating allergic rhinitis prepared in Examples 1-4 and Comparative Examples 1-3.

[0124] Test method: Take two sections of fresh nasal mucosal tissue from New Zealand white rabbits, fasten them to the two ends of a glass ampoule (mucosal surface facing outward), keep the glass ampoule at 37°C for 10 minutes, apply 0.2g of the test sample on the two sections of nasal mucosal tissue and keep it at 37°C for 10 minutes, then immediately fix one ampoule on the balance frame and the other on the adjustable bracket. Both ampoules are at the left end of the bracket. Adjust the height of the bracket to keep it balanced. Put a weighed beaker at the right end of the bracket and slowly drip tap water into the beaker at a uniform speed until the two sections of tissue adhered by the gel are just separated. Weigh the total mass of the beaker and water. Repeat 3 times for each sample and take the average value. The peeling force per unit area is the bioadhesion force (N / cm 2 ).

[0125] Figure 3 The bioadhesion results of Examples 1-4 and Comparative Examples 1-3 are shown in the figure. As shown in the figure, the bioadhesion of Examples 1-4 is 80-90 N / cm 2 , indicating that the bioadhesion is good and can reduce the clearance of drugs by nasal cilia; the bioadhesion of comparative examples 1-3 is 65-71N / cm 2 , indicating that the biological adhesion is poor and the clearance of the drug by the nasal cilia cannot be reduced; the nasal gel for treating allergic rhinitis in comparative example 1 does not contain a thermosensitive gel material, and cannot be gelled and attached to the nasal mucosa and nasal cilia, thereby failing to synergistically hinder the movement of the microspheres, resulting in poor biological adhesion and the inability to reduce the clearance of the drug by the nasal cilia; the dual-sensitive dual-network drug-loaded gel microspheres in comparative example 2 do not contain a thermosensitive polymer and an outer network structure, and the network structure of the gel microspheres has only a single-layer structure, and its pores, distribution and structural connectivity are adversely affected, resulting in poor biological adhesion and the inability to reduce the clearance of the drug by the nasal cilia; the dual-sensitive dual-network drug-loaded gel microspheres in comparative example 3 do not contain lactoferrin and an inner network structure, and the network structure of the gel microspheres has only a single-layer structure, which is not conducive to the pores, distribution and connectivity of the gel microspheres, thereby reducing the adhesion performance, resulting in poor biological adhesion and the inability to reduce the clearance of the drug by the nasal cilia.

[0126] Experimental Example 2

[0127] Swelling performance test

[0128] Test samples: nasal gels for treating allergic rhinitis prepared in Examples 1-4 and Comparative Examples 1-3.

[0129] Test method: freeze-dry the test samples and weigh them, the mass is recorded as M0, put the dried samples into PBS solution at 37°C and pH 7.0, take them out every 5 minutes, wipe the surface moisture with absorbent paper and weigh them, the mass is recorded as M1, do 3 parallel experiments for each group and take the average value, calculate the swelling rate (%) according to the following formula:

[0130] Swelling rate (%) = (M1-M0) / M0×100%

[0131] Figure 4 The swelling rate result diagram of Examples 1-4 and Comparative Examples 1-3 is shown; as shown in the figure, the swelling rates of Examples 1-4 within 5-25 minutes at 37°C and pH 7.0 are 1026-1178%, 1040-1169%, 1050-1182%, 1064-1190%, and 1080-1205%, respectively, indicating that the swelling rate is high at 37°C and pH 7.0, and the drug release is effectively controlled; the swelling rates of Comparative Examples 1-3 within 5-25 minutes at 37°C and pH 7.0 are 752-806%, 766-822%, 781-836%, 790-843%, and 807-860%, respectively, indicating that the swelling rate is low at 37°C and pH 7.0, and the drug release cannot be effectively controlled; the nasal gel for treating allergic rhinitis in Comparative Example 1 does not contain thermosensitive gel The material only contains dual-sensitive dual-network drug-loaded gel microspheres to exert swelling properties, but cannot reduce the movement and clearance of the microspheres in the nasal cavity, which is not conducive to the stabilization of the pH responsiveness and thermosensitivity of the microspheres, resulting in a low swelling rate at 37°C and pH 7.0, and cannot effectively control drug release; the dual-sensitive dual-network drug-loaded gel microspheres of comparative example 2 do not contain thermosensitive polymers and outer network structures, are neither thermosensitive, nor weaken the pH response release of sodium alginate, resulting in a low swelling rate at 37°C and pH 7.0, and cannot effectively control drug release; the dual-sensitive dual-network drug-loaded gel microspheres of comparative example 3 do not contain lactoferrin and inner network structures, which are not conducive to supporting the stability of the outer layer structure, and have an adverse effect on its thermosensitivity and pH response release, resulting in a low swelling rate at 37°C and pH 7.0, and cannot effectively control drug release.

[0132] Experimental Example 3

[0133] Treatment efficacy experiment

[0134] Test samples: nasal gels for treating allergic rhinitis prepared in Examples 1-4 and Comparative Examples 1-3.

[0135] Test method: 140 patients with allergic rhinitis of varying degrees were selected, with symptoms such as nasal congestion, nasal flow, sneezing, and nasal itching. Their ages ranged from 25 to 65 years old. They were enrolled using a random number table and divided into 7 groups, each with 20 patients. Each group used the corresponding test sample. The drug was administered through the nasal cavity twice a day. The effect was observed after 14 days. The treatment effect was determined according to the following criteria, and the treatment effectiveness rate (%) was calculated, specifically:

[0136] Effective: Allergic rhinitis symptoms completely disappeared, allergic rhinitis symptoms changed from severe to moderate, from moderate to mild, and from mild to normal;

[0137] Ineffective: There was no significant improvement in the symptoms of allergic rhinitis.

[0138] The formula for calculating the treatment effectiveness is as follows:

[0139] Treatment effectiveness (%) = effective number of people / 20×100%

[0140] Figure 5 The results of the therapeutic efficacy of Examples 1-4 and Comparative Examples 1-3 are shown in the figure; as shown in the figure, the therapeutic efficacy of Examples 1-4 is 80-95%, indicating that the effect of treating allergic rhinitis is better; the therapeutic efficacy of Comparative Examples 1-3 is 70-75%, indicating that the effect of treating allergic rhinitis is not good; the nasal gel for treating allergic rhinitis in Comparative Example 1 does not contain a thermosensitive gel material, and cannot cooperate with the dual-sensitive dual-network drug-loaded gel microspheres to adhere to the nasal cilia, which is not conducive to increasing the action time in the nasal cavity, resulting in a poor effect of treating allergic rhinitis; the dual-sensitive dual-network drug-loaded gel microspheres in Comparative Example 2 do not contain a thermosensitive polymer and an outer network structure, and the bioadhesion and drug release are adversely affected, reducing the bioavailability of the drug, resulting in a poor effect of treating allergic rhinitis; the dual-sensitive dual-network drug-loaded gel microspheres in Comparative Example 3 do not contain lactoferrin and an inner network structure, which is not conducive to the full contact between the traditional Chinese medicine components and the nasal mucosa, and also has an adverse effect on the drug release, reducing the bioavailability of the drug, resulting in a poor effect of treating allergic rhinitis.

[0141] The above experimental results show that the bioadhesion, swelling performance and therapeutic effect of Examples 1-4 of the present invention are significantly better than those of the samples of Comparative Examples 1-3. Among them, Example 1 using dual-sensitive dual-network drug-loaded gel microspheres and thermosensitive gel materials has better bioadhesion and swelling properties and better effect in treating allergic rhinitis. In the dual-sensitive dual-network drug-loaded gel microspheres, the outer network has pH sensitivity and temperature sensitivity, and the inner network has pH sensitivity, which can release the drug components therein in layers to reduce drug loss. The double-layer network structure is beneficial to support and protect the stability of the inner and outer structures respectively, and is beneficial to better respond to temperature and pH to release drugs. When the thermosensitive gel material is gelled, it softly adheres to the nasal cilia, and the dual-sensitive dual-network drug-loaded gel microspheres are better adhered to the nasal cavity, reducing the risk of being cleared and moved, and increasing the action time of the drug in the nasal cavity.

[0142] While the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that many changes, modifications, substitutions and variations can be made to the embodiments without departing from the principles and spirit of the invention.

[0143] The present invention and its implementation methods are described above, which is not restrictive. The drawings are only one of the implementation methods of the present invention, and the actual application is not limited thereto. In short, if ordinary technicians in the field are inspired by it and design methods and embodiments similar to the technical solution without creativity without departing from the purpose of the invention, they should all fall within the protection scope of the present invention.

Claims

1. A nasal gel for treating allergic rhinitis, characterized in that: The nasal gel for treating allergic rhinitis comprises the following components in parts by weight: 20-30 parts of dual-sensitive dual-network drug-loaded gel microspheres and 10-20 parts of thermosensitive gel materials; the dual-sensitive dual-network drug-loaded gel microspheres comprise the following components in parts by weight: 15-20 parts of sodium alginate, 2.5-5 parts of thermosensitive polymer, 3-4 parts of lactoferrin, 9-12 parts of traditional Chinese medicine extract, and 10-15 parts of calcium chloride; the thermosensitive gel material comprises the following components in parts by weight: 30-50 parts of silk fibroin, 10-20 parts of carboxymethyl chitosan, 5-10 parts of K-carrageenan, and 10-15 parts of genipin; the raw materials of the traditional Chinese medicine extract comprise the following components in parts by weight: 3-5 parts of platycodon, 3-5 parts of astragalus, 3-5 parts of atractylodes, 3-5 parts of tangerine peel, 3-5 parts of xanthium sibiricum, 3-5 parts of magnolia, 3-5 parts of angelica dahurica, and 3-5 parts of liquorice.

2. A method for preparing the nasal gel for treating allergic rhinitis according to claim 1, characterized in that: The specific steps include: S1. Place the silkworm cocoons in 80 mL of 0.5% sodium carbonate solution, heat and boil in a water bath for 30 min, wash thoroughly with deionized water, dry, weigh 4-6 g of the obtained silk fibroin fiber and dissolve it in 100 mL of 50% lithium bromide solution until it is completely dissolved, centrifuge, take the upper layer, transfer it to a dialysis bag, dialyze with deionized water and ultrapure water for 1-3 days, and obtain a silk fibroin solution; S2, 1.0-2.0g carboxymethyl chitosan and 0.5-1.0g K-carrageenan were mixed evenly, dissolved in 100-200mL deionized water, stirred evenly, 100mL of the silk fibroin solution described in step S1 was added dropwise, stirring was continued, and genipin was added to carry out cross-linking reaction for 1-2h to obtain a thermosensitive gel material; S3. Add the dual-sensitive dual-network drug-loaded gel microspheres into the thermosensitive gel material described in step S2, and disperse them evenly by ultrasound with an ultrasound power of 500-600 W and an ultrasound time of 20-30 min to obtain a nasal gel for treating allergic rhinitis.

3. The method for preparing the nasal gel for treating allergic rhinitis according to claim 2, characterized in that: In step S1, the mass fraction of silk fibroin in the solution is 3.0-5.0%.

4. The method for preparing the nasal gel for treating allergic rhinitis according to claim 3, characterized in that: In step S2, the amount of genipin added is 1.0-1.5 g.

5. The method for preparing the nasal gel for treating allergic rhinitis according to claim 4, characterized in that: The preparation method of the dual-sensitive dual-network drug-loaded gel microspheres specifically comprises the following steps: (1) Grind Platycodon grandiflorum, Astragalus membranaceus, Atractylodes macrocephala, Tangerine peel, Xanthium sibiricum, Magnolia officinalis, Angelica dahurica and Licorice root, pass through a 60-80 mesh sieve, mix evenly, add 4 times the amount of distilled water and boil for 2-3 times, filter while hot, combine the filtrate, and concentrate to 1 / 5 to 1 / 4 of the original volume of the filtrate to obtain a Chinese medicine extract; (2) 30-50 mL of a nanocrystalline cellulose aqueous suspension with a solid content of 1 g was replaced with anhydrous THF by a solvent replacement method, and then transferred to a round-bottom flask. 1.8 g of triethylamine and 1.5 g of 4-dimethylaminopyridine were added and magnetically stirred to obtain a mixed solution for standby use. 5.5 g of 2-bromoisobutyryl bromide was dissolved in 30-50 mL of anhydrous THF in advance and slowly added to the mixed solution through a constant pressure funnel in nitrogen. After the addition was complete, the bottle mouth was sealed and magnetically stirred at room temperature for 24 h. The product was washed 3-5 times with anhydrous THF, an equal volume mixture of anhydrous THF and anhydrous ethanol, and acetone to obtain modified nanocrystalline cellulose; (3) 0.2 g of cuprous bromide was placed in a reaction bottle, and washed with glacial acetic acid, anhydrous ethanol, and methanol for several times until the cuprous bromide turned light yellow. 300 mg of the modified nanocrystalline cellulose described in step (2), 11.0 g of recrystallized N-isopropylacrylamide, and 30-50 mL of methanol solution were added. The mixture was stirred magnetically, and the bottle mouth was sealed. The mixed solution was frozen and thawed several times by liquid nitrogen freeze-thaw method to remove oxygen to the maximum extent. After the mixture was warmed up, 0.2 mL of N,N,N',N',N''-pentamethyldiethyltriamine was added to the freeze-thaw solution through a syringe. The mixture was stirred magnetically at room temperature for 24 h. The reaction product was washed with methanol and anhydrous ethanol for 3-5 times to obtain a thermosensitive polymer. (4) adding lactoferrin to the Chinese medicine extract described in step (1), stirring magnetically for 5-6 hours, taking 1 / 2 of the Chinese medicine mixture and mixing it with 50 mL of a sodium alginate solution with a mass fraction of 3.0-4.0%, adding it to 50 mL of a calcium chloride solution with a mass fraction of 2.0-3.0% through a micro-injection pump, collecting the product, and obtaining inner layer drug-loaded gel microspheres; (5) The remaining 1 / 2 amount of the Chinese medicine mixture is mixed with 50 mL of a sodium alginate solution with a mass fraction of 3.0-4.0%, and the inner layer drug-loaded gel microspheres described in step (4) are placed therein for adsorption for 1-2 hours. The inner layer drug-loaded gel microspheres are taken out and then transferred to 50 mL of a calcium chloride solution containing the thermosensitive polymer described in step (3). The mixture is fully reacted for 2-3 hours. The microspheres are collected and washed with deionized water to obtain dual-sensitive dual-network drug-loaded gel microspheres.

6. The method for preparing the nasal gel for treating allergic rhinitis according to claim 5, characterized in that: In step (4), the amount of lactoferrin added is 0.6-0.8 g.

7. The method for preparing the nasal gel for treating allergic rhinitis according to claim 6, characterized in that: In step (5), in the calcium chloride solution, the mass fraction of calcium chloride is 2.0-3.0%, and the mass fraction of the thermosensitive polymer is 1.0-2.0%.

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