Preparation method of borneol-skin penetrating peptide composite in-situ gel and textile-based drug delivery system

Abstract

The invention belongs to the technical field of drug-loaded gel materials, and particularly relates to a preparation method of borneol-skin penetrating peptide composite in-situ gel and a textile-based drug-loaded system. The borneol and the skin penetrating peptide are bridged together through an azone structure, and the prepared borneol-skin penetrating peptide compound contains a lipophilic aliphatic chain, a keto group and a hydrophilic amino group, has a branched structure and a relatively large molecular weight, and can effectively improve the emulsification dispersion effect of a system, so that the particle size of the nano-emulsion is reduced, and the preparation method is simple and convenient. The distribution uniformity of the particle size of the nano-emulsion is improved. One end of the borneol-skin penetrating peptide compound molecule is of a borneol structure, the other end of the borneol-skin penetrating peptide compound molecule is of a polyarginine structure, an azone structure is contained on a middle chain segment, and the borneol-skin penetrating peptide compound molecule, the polyarginine structure and the azone structure jointly play a role and cooperate to improve the transdermal absorption effect.

Description

Technical Field

[0001] The invention belongs to the technical field of drug-carrying gel materials, and specifically relates to a preparation method of a borneol-skin-penetrating peptide composite in-situ gel and a textile-based drug-carrying system. Background Art

[0002] Hydrogels are hydrophilic, three-dimensional network-structured polymers that swell in water without dissolving. They combine the properties of water absorption, moisturizing, sustained release, and softness, and are widely used in biomedical fields such as soft contact lenses, cell and enzyme immobilization, drug delivery, and tissue engineering. Intelligent hydrogels, derived from smart materials, are able to sense subtle changes or stimuli in their external environment (such as temperature, pH, ionic strength, light, and electromagnetic fields) and respond sensitively, undergoing phase-volume mutations and exhibiting volume phase transition behavior. Temperature-sensitive in situ gels are liquids at low or room temperature that rapidly form semisolid gels upon application to the site of administration (such as an injection site or a mucous membrane).

[0003] Commonly used gel matrices for temperature-sensitive in situ gels include cellulose (methylcellulose and hydroxypropyl methylcellulose), chitosan, and poloxamer. Poloxamer, among others, has relatively low toxicity, minimal irritation to the skin and mucous membranes, good biocompatibility, and relatively stable chemical properties, making it an ideal carrier material for controlled drug release. Furthermore, to increase the rate of drug penetration into the skin, penetration enhancers such as azone, skin-penetrating peptides, and borneol are often added to the gel. However, these enhancers, due to their low molecular weight, often weaken the gel. Alternatively, to expand its scope of application and enhance ease of use, in situ gels can be combined with textile substrates to form drug-gel composite fabrics, which can then be adhered to the skin for transdermal drug delivery. However, conventional in situ gels and textile substrates, when formed through in situ deposition, exhibit low adhesion to the substrate, resulting in poor ease of use and durability. Summary of the Invention

[0004] In response to the above problems, the present invention provides a method for preparing a borneol-skin penetrating peptide composite in situ gel and a textile-based drug delivery system, which can solve the current problem of adhesion strength deviation between the in situ gel and the textile substrate.

[0005] To achieve the above object, the technical solution adopted by the present invention is: A method for preparing a borneol-skin-penetrating peptide composite in-situ gel comprises the following steps: uniformly mixing a surfactant, a cosurfactant, a borneol-skin-penetrating peptide composite, and ethyl oleate to obtain an oil phase; uniformly mixing water and the oil phase to obtain a nanoemulsion; and then mixing the nanoemulsion with a gel matrix to obtain a borneol-skin-penetrating peptide composite in-situ gel; wherein the surfactant is biscardanol polyoxyethylene ether, the cosurfactant is trans-isomerized heptadecanoic acid glycerol monoester, and the structure of the borneol-skin-penetrating peptide composite is as follows: ; The preparation method of the biscardanol polyoxyethylene ether is as follows: a biscardanol hydroxyl compound and ethylene oxide are subjected to a ring-opening polymerization reaction to obtain biscardanol polyoxyethylene ether; the structure of the biscardanol hydroxyl compound is as follows: .

[0006] Preferably, the molar ratio of the biscardol hydroxy compound to ethylene oxide is 1:9~12.

[0007] Preferably, the catalyst used in the ring-opening polymerization reaction is sodium isopropoxide, and the mass of sodium isopropoxide is 0.3-0.5% of the sum of the mass of the biscardol hydroxyl compound and ethylene oxide.

[0008] Preferably, the ring-opening polymerization reaction is carried out at a temperature of 155-165° C. and for a time of 10-12 hours.

[0009] Preferably, the mass ratio of the surfactant, the cosurfactant, the borneol-skin penetrating peptide complex, ethyl oleate and water is 20:7-8:1-1.5:2-3:180-220.

[0010] Preferably, the mass ratio of the nanoemulsion to the gel matrix is ​​100:8-10.

[0011] Preferably, the gel matrix is ​​poloxamer P407.

[0012] The invention relates to an application of the borneol-skin penetrating peptide composite in situ gel prepared by the preparation method of the borneol-skin penetrating peptide composite in situ gel as a textile-based drug delivery system.

[0013] Preferably, the textile-based drug delivery system comprises a drug gel layer and a textile substrate. The preparation method of the drug gel layer is as follows: a surfactant, a cosurfactant, a borneol-skin penetrating peptide complex, a drug and ethyl oleate are mixed to obtain an oil phase; water and the oil phase are then mixed to obtain a drug-containing nanoemulsion; and the drug-containing nanoemulsion and the gel matrix are then mixed and placed on the textile substrate to form a drug gel layer.

[0014] Preferably, the drug is ligustrazine, and the textile substrate is cotton fabric.

[0015] Compared with the prior art, the preparation method of the borneol-skin penetrating peptide composite in situ gel and the textile-based drug delivery system of the present invention have the following beneficial effects: (1) The present invention bridges borneol and skin-penetrating peptides through an azone structure. The prepared borneol-skin-penetrating peptide complex contains a lipophilic fatty chain, a ketone group, and a hydrophilic amino group, and has a branched structure and a large molecular weight, which can effectively improve the emulsification and dispersion effect of the system, thereby reducing the particle size of the nanoemulsion and improving the distribution uniformity of the nanoemulsion particle size. The present invention uses bis-cardanol polyoxyethylene ether as an emulsifier and trans-isomerized heptadecanol monoglyceride as an auxiliary emulsifier, which has a good emulsification and dispersion effect. Bis-cardanol polyoxyethylene ether contains two long fatty chains and a long polyoxyethylene ether chain segment, which cooperate with each other to improve the surface activity of the surfactant; trans-isomerized heptadecanol monoglyceride contains hydrophilic hydroxyl groups and lipophilic ester groups. At the same time, it has a trans structure, has less steric hindrance, and exhibits a stronger emulsification and dispersion effect.

[0016] (2) The present invention prepares a nanoemulsion with a smaller particle size and good particle size distribution uniformity into a drug-containing nanoemulsion, and prepares the drug-containing nanoemulsion into a drug gel. The borneol-skin penetrating peptide complex molecule in the drug gel has a borneol structure at one end and a polyarginine structure at the other end, and contains an azone structure on the middle chain segment. The three work together and cooperate synergistically to improve transdermal absorption. Moreover, since the borneol-skin penetrating peptide complex has certain hydrophilicity and hydrophobicity, it can effectively lock the water passing through the gel, and its branched structure can reduce the pores of the gel, so that the gel has an appropriate water vapor permeability, which is close to the water vapor permeability of human skin, which is beneficial to reduce the loss of fluid in the body, accelerate cell migration, and keep the wound surface locally moist.

[0017] (3) The borneol-skin penetrating peptide complex prepared in the present invention has a large molecular weight and contains polar amino groups and branched fatty chains in the molecular chain. The polar amino groups can improve the wettability of the gel matrix to the cotton fabric substrate and increase the adhesion strength through hydrogen bonding and other forces. In addition, the branched fatty chains have a good penetrating pulling effect and can firmly and stably adhere to the cotton fabric substrate, thereby improving the peel strength between the drug gel and the cotton fabric and other fabric substrates. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is the H NMR spectrum of the borneol-skin penetrating peptide complex prepared in Example 1 of the present invention; Figure 2 This is the H NMR spectrum of the biscardol hydroxy compound prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0019] In order to make the skilled in the art better understand the technical solutions, the application is described in detail below in conjunction with examples, and the description in this part is only exemplary and explanatory, and should not have any limiting effect on the protection scope of the application.

[0020] Example 1

[0021] The preparation method of the borneol-skin penetrating peptide composite in-situ gel of the present embodiment comprises the following steps: (1) Borneol, sodium hydride and N,N-dimethylformamide are added into a reaction kettle, heated to 50℃, and stirred for 3h, then dibromohydrocarbon is added into the reaction kettle, heated to 80℃, and stirred for 8h, then distilled under reduced pressure to obtain a concentrated solution, the concentrated solution is added into water to precipitate, and the precipitate is dried to obtain brominated borneol; wherein the dibromohydrocarbon is 1,5-dibromo-3,3-dimethylpentane, the molar ratio of borneol, sodium hydride and dibromohydrocarbon is 1:1:1, and the mass of N,N-dimethylformamide is 120% of the mass of borneol.

[0022] (2) Borneol, 6-hydroxyhomopiperidin-2-one, potassium hydroxide, potassium carbonate, tetrabutylammonium bromide and toluene are added into a reaction kettle, stirred uniformly, heated to 80℃, and stirred for 7h, then cooled to room temperature and filtered, the filtrate is distilled under reduced pressure to obtain a concentrate, and the concentrate is purified by column chromatography (eluent consisting of ethyl acetate, dichloromethane and methanol in a volume ratio of 6:2:1) to obtain a borneol grafted azone compound; wherein the molar ratio of brominated borneol and 6-hydroxyhomopiperidin-2-one is 1:1, the mass ratio of brominated borneol, potassium hydroxide, potassium carbonate, tetrabutylammonium bromide and toluene is 1:1.1:1.4:0.13:6.5, and the chemical structure of the borneol grafted azone compound is as follows: .

[0023] (3) Add skin-penetrating peptide, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, 4-dimethylaminopyridine and anhydrous tetrahydrofuran into a reactor, stir and react for 5 hours, then add borneol-grafted azole compound into the reactor, continue stirring and reacting for 30 hours, remove the solvent by vacuum distillation to obtain a concentrate, and purify the concentrate by column chromatography (eluent consists of ethyl acetate, dichloromethane and methanol in a volume ratio of 5:3:2) to obtain a borneol-skin-penetrating peptide complex; The skin-penetrating peptide is a polymerized arginine, the polymerized arginine is a nona-arginine, the molar ratio of the skin-penetrating peptide, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, 4-dimethylaminopyridine and the borneol-grafted azone compound is 1:35:3:1, the mass of anhydrous tetrahydrofuran is 70% of the sum of the masses of the skin-penetrating peptide, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and 4-dimethylaminopyridine, and the nuclear magnetic resonance spectroscopy of the borneol-skin-penetrating peptide complex is as follows: Figure 1 As shown, the chemical structure is as follows: .

[0024] (4) Adding a surfactant, a co-surfactant and a borneol-skin penetrating peptide complex into a stirring tank and stirring evenly, then adding ethyl oleate and stirring evenly to obtain an oil phase; then, under stirring conditions, adding deionized water into the oil phase and stirring evenly to obtain a nanoemulsion; wherein the mass ratio of the surfactant, the co-surfactant, the borneol-skin penetrating peptide complex, ethyl oleate and deionized water is 20:7:1:2:180, the surfactant is bis-cardanol polyoxyethylene ether, and the co-surfactant is trans-isomerized heptadecanol monoglyceride; the structure of trans-isomerized heptadecanol monoglyceride is as follows: .

[0025] The preparation method of biscardol polyoxyethylene ether is as follows: ① Add cardanol, cardanol glycidyl ether, tetrabutylammonium bromide and tetrahydrofuran into a reaction kettle, heat to 75°C, stir and react for 6 hours, and distill under reduced pressure to remove tetrabutylammonium bromide and tetrahydrofuran to obtain a biscardanol hydroxy compound; wherein the molar ratio of cardanol to cardanol glycidyl ether is 1:1, the mass of tetrabutylammonium bromide is 3% of the sum of the mass of cardanol and cardanol glycidyl ether, and the mass of tetrahydrofuran is 60% of the sum of the mass of cardanol and cardanol glycidyl ether. The nuclear magnetic hydrogen spectrum of the biscardanol hydroxy compound is as follows: Figure 2 As shown, the chemical structure is as follows: .

[0026] ② Add biscardanol hydroxyl compound, ethylene oxide and sodium isopropoxide to a reactor, then introduce nitrogen into the reactor, stir evenly under sealing and heat to 155°C, stir and react for 10 hours, distill under reduced pressure to remove unreacted ethylene oxide, and then neutralize sodium isopropoxide with acetic acid to obtain biscardanol polyoxyethylene ether; wherein the molar ratio of biscardanol hydroxyl compound to ethylene oxide is 1:9, and the mass of sodium isopropoxide is 0.3% of the sum of the mass of biscardanol hydroxyl compound and ethylene oxide.

[0027] (5) The nanoemulsion and gel matrix were added to a stirred tank at a mass ratio of 100:8, stirred and mixed, and then allowed to stand at 4°C for 24 hours to obtain a borneol-skin-penetrating peptide composite in situ gel; wherein the gel matrix was poloxamer P407. The borneol-skin-penetrating peptide composite in situ gel prepared in this example can gel at 33°C.

[0028] Example 2

[0029] The preparation method of the borneol-skin-penetrating peptide composite in situ gel of this embodiment comprises the following steps: (1) Borneol, sodium hydride and N,N-dimethylformamide were added to a reactor, heated to 55°C, stirred and reacted for 4 hours, and then dibromohydrocarbon was added to the reactor, heated to 85°C, stirred and reacted for 9 hours, and distilled under reduced pressure to obtain a concentrated solution. The concentrated solution was added to water to precipitate, and the precipitate was dried to obtain brominated borneol; wherein the dibromohydrocarbon was 1,5-dibromo-3,3-dimethylpentane, the molar ratio of borneol, sodium hydride and dibromohydrocarbon was 1:1:1, and the mass of N,N-dimethylformamide was 140% of the mass of borneol.

[0030] (2) Bromoborneol, 6-hydroxyhomopiperidin-2-one, potassium hydroxide, potassium carbonate, tetrabutylammonium bromide and toluene were added to a reaction kettle, stirred evenly, heated to 82°C, stirred for reaction for 8 hours, cooled to room temperature and filtered, and the filtrate was distilled under reduced pressure to obtain a concentrate, which was purified by column chromatography (the eluent was composed of ethyl acetate, dichloromethane and methanol in a volume ratio of 6:2:1) to obtain a borneol-grafted azone compound; wherein the molar ratio of bromoborneol to 6-hydroxyhomopiperidin-2-one was 1:1, and the mass ratio of bromoborneol, potassium hydroxide, potassium carbonate, tetrabutylammonium bromide and toluene was 1:1.2:1.5:0.15:7. The chemical structure of the borneol-grafted azone compound is as follows: .

[0031] (3) adding skin-penetrating peptide, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, 4-dimethylaminopyridine and anhydrous tetrahydrofuran into a reactor, stirring and mixing for 6 hours, then adding borneol-grafted azole compound into the reactor, continuing to stir and react for 32 hours, and removing the solvent by vacuum distillation to obtain a concentrate, which was purified by column chromatography (eluent consisting of ethyl acetate, dichloromethane and methanol in a volume ratio of 5:3:2) to obtain a borneol-skin-penetrating peptide complex; In the invention, the skin-penetrating peptide is a polymerized arginine, the polymerized arginine is a nona-arginine, the molar ratio of the skin-penetrating peptide, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, 4-dimethylaminopyridine and the borneol-grafted azone compound is 1:37:3.5:1, the mass of anhydrous tetrahydrofuran is 80% of the sum of the masses of the skin-penetrating peptide, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and 4-dimethylaminopyridine, and the chemical structure of the borneol-skin-penetrating peptide complex is as follows: .

[0032] (4) Adding a surfactant, a co-surfactant and a borneol-skin penetrating peptide complex into a stirring tank and stirring evenly, then adding ethyl oleate and stirring evenly to obtain an oil phase; then, under stirring conditions, adding deionized water into the oil phase and stirring evenly to obtain a nanoemulsion; wherein the mass ratio of the surfactant, the co-surfactant, the borneol-skin penetrating peptide complex, ethyl oleate and deionized water is 20:7.5:1.2:2.5:200, the surfactant is bis-cardanol polyoxyethylene ether, and the co-surfactant is trans-isomerized heptadecanol monoglyceride; the structure of trans-isomerized heptadecanol monoglyceride is as follows: .

[0033] The preparation method of biscardol polyoxyethylene ether is as follows: ① Add cardanol, cardanol glycidyl ether, tetrabutylammonium bromide, and tetrahydrofuran to a reactor, heat to 78°C, stir and react for 7 hours, and distill under reduced pressure to remove tetrabutylammonium bromide and tetrahydrofuran to obtain a biscardanol hydroxy compound; wherein the molar ratio of cardanol to cardanol glycidyl ether is 1:1, the mass of tetrabutylammonium bromide is 4% of the sum of the mass of cardanol and cardanol glycidyl ether, and the mass of tetrahydrofuran is 70% of the sum of the mass of cardanol and cardanol glycidyl ether. The chemical structure of the biscardanol hydroxy compound is as follows: .

[0034] ② Add biscardanol hydroxyl compound, ethylene oxide and sodium isopropoxide to a reactor, then introduce nitrogen into the reactor, stir evenly under sealing and heat to 160°C, stir and react for 11 hours, distill under reduced pressure to remove unreacted ethylene oxide, and then neutralize sodium isopropoxide with acetic acid to obtain biscardanol polyoxyethylene ether; wherein the molar ratio of biscardanol hydroxyl compound to ethylene oxide is 1:10, and the mass of sodium isopropoxide is 0.4% of the sum of the mass of biscardanol hydroxyl compound and ethylene oxide.

[0035] (5) The nanoemulsion and gel matrix were added to a stirred tank at a mass ratio of 100:9, stirred and mixed, and then allowed to stand at 4°C for 28 hours to obtain a borneol-skin-penetrating peptide composite in situ gel; wherein the gel matrix was poloxamer P407. The borneol-skin-penetrating peptide composite in situ gel prepared in this example can gel at 33°C.

[0036] Example 3

[0037] The preparation method of the borneol-skin-penetrating peptide composite in situ gel of this embodiment comprises the following steps:

[0038] (1) Borneol, sodium hydride and N,N-dimethylformamide were added to a reactor, heated to 60°C, and stirred for 5 hours. Then, dibromohydrocarbon was added to the reactor, heated to 90°C, and stirred for 10 hours. The concentrated solution was distilled under reduced pressure to obtain a concentrate. The concentrate was added to water to precipitate. The precipitate was dried to obtain brominated borneol; wherein the dibromohydrocarbon was 1,5-dibromo-3,3-dimethylpentane, the molar ratio of borneol, sodium hydride and dibromohydrocarbon was 1:1:1, and the mass of N,N-dimethylformamide was 150% of the mass of borneol.

[0039] (2) Bromoborneol, 6-hydroxyhomopiperidin-2-one, potassium hydroxide, potassium carbonate, tetrabutylammonium bromide and toluene were added to a reaction kettle, stirred evenly, heated to 85°C, stirred for 9 hours, cooled to room temperature and filtered, and the filtrate was distilled under reduced pressure to obtain a concentrate, which was purified by column chromatography (the eluent was composed of ethyl acetate, dichloromethane and methanol in a volume ratio of 6:2:1) to obtain a borneol-grafted nitrone compound; wherein the molar ratio of bromoborneol to 6-hydroxyhomopiperidin-2-one was 1:1, and the mass ratio of bromoborneol, potassium hydroxide, potassium carbonate, tetrabutylammonium bromide and toluene was 1:1.3:1.6:0.17:8. The chemical structure of the borneol-grafted nitrone compound is as follows: .

[0040] (3) Add skin-penetrating peptide, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, 4-dimethylaminopyridine and anhydrous tetrahydrofuran into a reactor, stir and react for 8 hours, then add borneol-grafted azole compound into the reactor, continue stirring and react for 35 hours, remove the solvent by vacuum distillation to obtain a concentrate, and purify the concentrate by column chromatography (eluent consists of ethyl acetate, dichloromethane and methanol in a volume ratio of 5:3:2) to obtain a borneol-skin-penetrating peptide complex; The skin-penetrating peptide is a polymerized arginine, the polymerized arginine is a nona-arginine, the molar ratio of the skin-penetrating peptide, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, 4-dimethylaminopyridine, and the borneol-grafted azone compound is 1:40:4:1, the mass of anhydrous tetrahydrofuran is 90% of the sum of the masses of the skin-penetrating peptide, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, and 4-dimethylaminopyridine, and the chemical structure of the borneol-skin-penetrating peptide complex is as follows: .

[0041] (4) Adding a surfactant, a co-surfactant and a borneol-skin penetrating peptide complex into a stirring tank and stirring evenly, then adding ethyl oleate and stirring evenly to obtain an oil phase; then, under stirring conditions, adding deionized water into the oil phase and stirring evenly to obtain a nanoemulsion; wherein the mass ratio of the surfactant, the co-surfactant, the borneol-skin penetrating peptide complex, ethyl oleate and deionized water is 20:8:1.5:3:220, the surfactant is bis-cardanol polyoxyethylene ether, and the co-surfactant is trans-isomerized heptadecanol monoglyceride; the structure of trans-isomerized heptadecanol monoglyceride is as follows: .

[0042] The preparation method of biscardol polyoxyethylene ether is as follows: ① Add cardanol, cardanol glycidyl ether, tetrabutylammonium bromide, and tetrahydrofuran to a reactor, heat to 80°C, stir and react for 8 hours, and distill under reduced pressure to remove tetrabutylammonium bromide and tetrahydrofuran to obtain a biscardanol hydroxy compound; wherein the molar ratio of cardanol to cardanol glycidyl ether is 1:1, the mass of tetrabutylammonium bromide is 5% of the sum of the mass of cardanol and cardanol glycidyl ether, and the mass of tetrahydrofuran is 80% of the sum of the mass of cardanol and cardanol glycidyl ether. The chemical structure of the biscardanol hydroxy compound is as follows: .

[0043] (2) adding the double-benzoin phenol hydroxyl compound, the ethylene oxide and the sodium isopropylate into a reaction kettle, then introducing nitrogen into the reaction kettle, stirring uniformly under sealing, heating to 165℃, stirring for 12h, removing unreacted ethylene oxide by distillation under reduced pressure, then neutralizing the sodium isopropylate with acetic acid to obtain the double-benzoin phenol polyoxyethylene ether; wherein the molar ratio of the double-benzoin phenol hydroxyl compound to the ethylene oxide is 1:12, and the mass of the sodium isopropylate is 0.5% of the sum of the mass of the double-benzoin phenol hydroxyl compound and the mass of the ethylene oxide.

[0044] (5) adding the nanoemulsion and the gel matrix according to a mass ratio of 100:10 into a stirring kettle, stirring uniformly, then standing for 30h in a 4℃ environment to obtain the borneol-skin penetrating peptide composite in-situ gel; wherein the gel matrix is poloxamer P407. The borneol-skin penetrating peptide composite in-situ gel prepared in this example can gel at 33℃.

[0045] Comparative Example 1

[0046] The preparation method of the borneol-skin penetrating peptide composite in-situ gel of this comparative example is different from the preparation method of the borneol-skin penetrating peptide composite in-situ gel of Example 1 only in that the dibromohydrocarbon in step (1) of the preparation method of the borneol-skin penetrating peptide composite in-situ gel of this comparative example is 1,5-dibromopentane.

[0047] Comparative Example 2

[0048] The preparation method of the borneol-skin penetrating peptide composite in-situ gel of this comparative example is different from the preparation method of the borneol-skin penetrating peptide composite in-situ gel of Example 1 only in that the dibromohydrocarbon in step (1) of the preparation method of the borneol-skin penetrating peptide composite in-situ gel of this comparative example is 1,3-dibromopropane.

[0049] Comparative Example 3

[0050] The preparation method of the borneol-skin penetrating peptide composite in-situ gel of this comparative example is different from the preparation method of the borneol-skin penetrating peptide composite in-situ gel of Example 1 only in that the dibromohydrocarbon in step (1) of the preparation method of the borneol-skin penetrating peptide composite in-situ gel of this comparative example is 1,8-dibromooctane.

[0051] Comparative Example 4

[0052] The preparation method of the borneol-skin penetrating peptide composite in-situ gel of this comparative example is different from the preparation method of the borneol-skin penetrating peptide composite in-situ gel of Example 1 only in that the dibromohydrocarbon in step (1) of the preparation method of the borneol-skin penetrating peptide composite in-situ gel of this comparative example is 2,5-dibromohexane.

[0053] Comparative Example 5

[0054] The difference between the preparation method of the borneol-skin-penetrating peptide composite in situ gel of this comparative example and the preparation method of the borneol-skin-penetrating peptide composite in situ gel of Example 1 is that in step (4) of the preparation method of the borneol-skin-penetrating peptide composite in situ gel of this comparative example, the borneol-skin-penetrating peptide complex is replaced by a mixture of borneol, N-laurylcaprolactam and nona-arginine in a molar ratio of 1:1:1.

[0055] Comparative Example 6

[0056] The difference between the preparation method of the borneol-skin-penetrating peptide composite in situ gel of this comparative example and the preparation method of the borneol-skin-penetrating peptide composite in situ gel of Example 1 is that the cosurfactant in step (4) of the preparation method of the borneol-skin-penetrating peptide composite in situ gel of this comparative example is isomeric heptadecanoic acid glyceryl monoester, and the structure of isomeric heptadecanoic acid glyceryl monoester is as follows: .

[0057] Comparative Example 7

[0058] The preparation method of the borneol-skin penetrating peptide composite in situ gel of this comparative example is different from the preparation method of the borneol-skin penetrating peptide composite in situ gel of Example 1 only in that in step (4) of the preparation method of the borneol-skin penetrating peptide composite in situ gel of this comparative example, dicardanol polyoxyethylene ether is replaced by cardanol polyoxyethylene ether. The preparation method of cardanol polyoxyethylene ether is as follows: cardanol, ethylene oxide and sodium isopropoxide are added to a reactor, and then nitrogen is introduced into the reactor. After stirring evenly under sealing, the reaction is heated to 155°C, stirred for reaction for 10 hours, and distilled under reduced pressure to remove unreacted ethylene oxide. Then, sodium isopropoxide is neutralized with acetic acid to obtain cardanol polyoxyethylene ether; wherein the molar ratio of cardanol to ethylene oxide is 1:9, and the mass of sodium isopropoxide is 0.3% of the sum of the masses of cardanol and ethylene oxide.

[0059] Experimental example

[0060] In order to investigate the basic properties of the nanoemulsions prepared in the examples and comparative examples, the average particle size and particle size distribution index of the nanoemulsions prepared in the examples and comparative examples were measured using a laser particle size analyzer. The experimental results are shown in Table 1.

[0061] Table 1 Average particle size and particle size distribution index of nanoemulsions prepared in various examples and comparative examples

[0062] As shown in Table 1, the average particle size of the nanoemulsions prepared in Examples 1-3 of the present invention is 8.12-8.20 nm, and the particle size distribution index is less than 0.045, indicating that the nanoemulsions prepared in the present invention have a smaller particle size and a better particle size distribution uniformity. It is proved that the surfactants and cosurfactants used in the present invention have a better emulsification and dispersion effect. This is because the bis-cardanol polyoxyethylene ether contains two long fatty chains and a long polyoxyethylene ether chain segment, which cooperate with each other to improve the surface activity of the surfactant; the trans-isomerized heptadecanoic acid glycerol monoester contains hydrophilic hydroxyl groups and lipophilic ester groups, and at the same time, it is a trans structure with less steric hindrance, showing a stronger emulsification and dispersion effect; in addition, the borneol-skin penetrating peptide complex contains a lipophilic fatty chain, a ketone group and a hydrophilic amino group, and has a branched structure and a larger molecular weight, which can also improve the emulsification and dispersion effect of the system to a certain extent, thereby reducing the particle size of the nanoemulsion and improving the distribution uniformity of the nanoemulsion particle size.

[0063] It can be seen from Example 1 and Comparative Examples 1-4 that the degree of branching and carbon chain length of the fatty chain of the bridged polymerized arginine and borneol have a certain influence on the particle size and particle size distribution uniformity of the nanoemulsion. This may be because a larger degree of branching of the fatty chain can increase steric hindrance, improve the emulsification and dispersion effect and emulsion stability, and a fatty chain of appropriate length can improve the hydrophilic and lipophilic balance of the system, thereby reducing the particle size of the nanoemulsion and improving the uniformity of the particle size distribution of the nanoemulsion.

[0064] It can be seen from Example 1 and Comparative Example 5 that when a mixture of borneol, N-laurylcaprolactam and nona-arginine is used, the equilibrium stability of the system is poor due to its small molecular weight, resulting in a larger particle size of the nanoemulsion and poor particle size distribution uniformity.

[0065] It can be seen from the Examples and Comparative Examples 6-7 that when isoheptadecanoic acid glycerol monoester is used as a cosurfactant, its terminal methyl group has a large steric hindrance, resulting in poor system balance, resulting in larger nanoemulsion particle size and poor particle size distribution uniformity.

[0066] Effect Examples

[0067] In order to evaluate the drug loading effect of the borneol-skin penetrating peptide composite in situ gel prepared in each example and comparative example, the experiment was repeated according to the method of each example and comparative example, except that, when preparing the oil phase in step (4) of each example and comparative example, ligustrazine was added to the stirring tank to obtain a nanoemulsion containing ligustrazine, and then the nanoemulsion containing ligustrazine and the gel matrix were stirred and mixed in a mass ratio of 100:8 and allowed to stand to obtain a drug gel containing ligustrazine. The mass fraction of ligustrazine in the drug gel corresponding to different in situ gels was the same. The drug gel was then subjected to an in vitro transdermal permeation test. The experimental method was as follows: ICR mice were shaved of their abdominal hair, sacrificed by cervical dislocation, and skin was excised. Subcutaneous fat and fascia were removed. The mice were washed with saline and mounted in a Franz diffusion cell with the stratum corneum facing the donor cell. The drug gel was then applied to the stratum corneum. A receptor medium (prepared by stirring a mixture of ethanol and saline in a volume ratio of 1:3) was added to the receptor cell. The diffusion cell temperature was set at 36.0°C and the magnetic stirring speed was set at 200 r / min. 0.5 mL of receptor fluid was extracted at 0, 2, 4, 6, 8, 10, 12, and 24 h after the start of the experiment. The same volume of receptor fluid at the same temperature was added simultaneously. The extracted receptor fluid was filtered through a microporous membrane and analyzed. The transdermal permeation rate constant of ligustrazine in the drug gel was calculated. The experiment was repeated three times for each drug gel, and the average value was calculated after the experiment. The experimental results are shown in Table 2.

[0068] In addition, the water vapor transmission rate of the borneol-skin penetrating peptide composite in situ gels prepared in each embodiment and comparative example at 36.0°C was tested using a water vapor transmission rate tester. The temperature during the test was 36.0°C and the humidity was 60%. The experiment was repeated three times for each in situ gel, and the average value was calculated after the experiment. The experimental results are shown in Table 2.

[0069] Table 2 Transdermal rate constants of ligustrazine in the corresponding drug gels prepared in the examples and comparative examples and water vapor permeability of the in situ gels

[0070] As shown in Table 2, after ligustrazine and the in situ gel of the present invention are prepared into drug gel, ligustrazine has a larger transdermal rate constant, which is between 272 and 275 μg / (cm -2 h), the water vapor transmission rate is between 209~215g / (m 2·day), proving that the gel of the present invention can effectively promote drug penetration into the skin and improve the skin permeability of drugs. This result proves that the borneol-skin penetrating peptide complex prepared by the present invention has a better skin penetration-promoting effect than borneol, N-laurylcaprolactam, and nona-arginine. This is because the molecule has a borneol structure at one end and a polyarginine structure at the other end, and contains an azone structure in the middle segment. The three work together and cooperate to improve transdermal absorption. In addition, the in-situ gel of the present invention has an appropriate water vapor permeability, close to that of human skin, which is beneficial for reducing the loss of fluid in the body, accelerating cell migration, and keeping the wound surface locally moist.

[0071] According to the results in Table 1, in Comparative Examples 1-5, the branching degree and carbon chain length of the fatty chains of the bridged polymerized arginine and borneol not only affect the particle size and particle size distribution uniformity of the nanoemulsion, but may also affect the transdermal absorption effect, resulting in a smaller transdermal rate constant; at the same time, the smaller degree of branching in the molecular chain and the change in the length of the fatty carbon chain lead to an increase in the porosity of the system, resulting in a significant increase in the water vapor permeability and poor moisture retention. In Comparative Examples 6-7, due to the changes in the surfactant and co-surfactant, the particle size of the nanoemulsion is larger and the particle size distribution uniformity is poor, which in turn leads to poor emulsion particle size and distribution uniformity of the drug in the drug gel, affecting the drug transdermal rate and water vapor permeability.

[0072] Application Examples

[0073] In order to investigate the application prospects of the borneol-skin-penetrating peptide composite in situ gels prepared in each example and comparative example as textile medical drug carriers, cotton fabric was laid flat on the bottom of a square mold, and then a nanoemulsion containing ligustrazine was prepared according to the method in the effect example. The nanoemulsion containing ligustrazine and the gel matrix were stirred and mixed in a mass ratio of 100:8 and placed in a square mold. After standing for 28 hours in a 36° environment, a gel composite fabric was obtained. The mass fraction of ligustrazine in the gel composite fabric corresponding to different in situ gels was the same. The 180° peel strength between the drug gel and the cotton fabric was then tested using a tensile tester. The experiment was repeated three times for each sample, and the average of the three experimental results was used as the final experimental result. The experimental results are shown in Table 3.

[0074] Table 3 Peel strength between the drug gel and cotton fabric corresponding to the borneol-skin penetrating peptide composite in situ gel prepared in each example and comparative example

[0075] As shown in Table 3, the drug gel of the present invention has high adhesion strength to cotton fabric, demonstrating strong bonding between the hydrogel layer and cotton fabric, and promising long-term application prospects. These results indicate that the borneol-skin-penetrating peptide complex has a large molecular weight and contains polar amino groups and branched fatty chains in its molecular chain. The polar amino groups can improve the wettability of the gel matrix to the cotton fabric substrate and enhance adhesion strength through forces such as hydrogen bonding. Furthermore, the branched fatty chains have a strong penetrating pulling effect, allowing for strong and stable adhesion to the cotton fabric substrate, thereby improving the peel strength between the drug gel and the cotton fabric.

[0076] Finally, in order to investigate the irritation of the borneol-skin-penetrating peptide composite in situ gel prepared in each example, the borneol-skin-penetrating peptide composite in situ gel prepared in each example was administered by rectal administration, so that the contact time between the gel and the rectal mucosa was controlled at 5 h, and the gel was applied once a day for 10 consecutive days. The mass of gel applied to each mouse per day was 0.3 g, and the mice were observed every day for the presence of secretions and the like in the anus. On the 12th day of the experiment, the mice were killed and dissected, and the rectal mucosa was removed and observed for congestion, edema, congestion, etc. The experimental results showed that the rectal mucosa of the mice administered with the borneol-skin-penetrating peptide composite in situ gel of Examples 1-3 did not show congestion, edema, etc., proving that the borneol-skin-penetrating peptide composite in situ gel of the present invention has less irritation.

[0077] It should be noted that, in this article, the terms: include, contain and any other variations are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also other elements that are not explicitly listed, or also includes elements that are inherent to such process, method, article or device. Specific examples are used herein to illustrate the principles and implementation methods of the technical solution of the present invention. The above examples are only used to help understand the method of the present invention and its core idea. The above is only a preferred embodiment of the present invention. It should be pointed out that due to the limitations of textual expression, there are objectively infinite specific structures. For ordinary technicians in this technical field, without departing from the principles of the present invention, several improvements, modifications or changes can be made, and the above technical features can be combined in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the concept and technical solution of the present invention to other occasions without improvement, should be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing a borneol-skin penetrating peptide composite in situ gel, characterized in that: The following steps are involved: A surfactant, a co-surfactant, a borneol-skin penetrating peptide complex and ethyl oleate are mixed to obtain an oil phase; water and the oil phase are then mixed to obtain a nanoemulsion; the nanoemulsion is then mixed with a gel matrix to obtain a borneol-skin penetrating peptide composite in situ gel; the surfactant is biscardanol polyoxyethylene ether, the co-surfactant is trans-isomerized heptadecanoic acid glycerol monoester, and the structure of the borneol-skin penetrating peptide complex is as follows: ； The preparation method of the biscardanol polyoxyethylene ether is as follows: a biscardanol hydroxyl compound and ethylene oxide are subjected to a ring-opening polymerization reaction to obtain biscardanol polyoxyethylene ether; the structure of the biscardanol hydroxyl compound is as follows: 。 2. The method for preparing the borneol-skin penetrating peptide composite in situ gel according to claim 1, characterized in that: The molar ratio of the biscardol hydroxy compound to ethylene oxide is 1:9-12.

3. The method for preparing the borneol-skin penetrating peptide composite in situ gel according to claim 2, characterized in that: The catalyst used in the ring-opening polymerization reaction is sodium isopropoxide, and the mass of the sodium isopropoxide is 0.3-0.5% of the sum of the mass of the biscardanol hydroxyl compound and the ethylene oxide.

4. The method for preparing the borneol-skin penetrating peptide composite in situ gel according to claim 3, characterized in that: The temperature of the ring-opening polymerization reaction is 155-165° C., and the time is 10-12 hours.

5. The method for preparing the borneol-skin penetrating peptide composite in situ gel according to any one of claims 1 to 4, characterized in that: The mass ratio of the surfactant, the cosurfactant, the borneol-skin penetrating peptide complex, ethyl oleate and water is 20:7-8:1-1.5:2-3:180-220.

6. The method for preparing the borneol-skin penetrating peptide composite in situ gel according to any one of claims 1 to 4, characterized in that: The mass ratio of the nanoemulsion to the gel matrix is ​​100:8-10.

7. The method for preparing the borneol-skin penetrating peptide composite in situ gel according to any one of claims 1 to 4, characterized in that: The gel matrix is ​​poloxamer P407.

8. Use of the borneol-skin-penetrating peptide composite in situ gel prepared by the method for preparing the borneol-skin-penetrating peptide composite in situ gel according to any one of claims 1 to 7 as a textile-based drug delivery system.

9. The use according to claim 8, characterized in that The textile-based drug-carrying system includes a drug gel layer and a textile substrate. The preparation method of the drug gel layer is as follows: a surfactant, a co-surfactant, a borneol-skin-penetrating peptide complex, a drug, and ethyl oleate are mixed to obtain an oil phase; water and the oil phase are then mixed to obtain a drug-containing nanoemulsion; and the drug-containing nanoemulsion and a gel matrix are mixed and placed on the textile substrate to form a drug gel layer.

10. The use according to claim 8, characterized in that The drug is ligustrazine, and the textile substrate is cotton fabric.

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