An insulin gel composition

Abstract

The present application belongs to the technical field of medicine, and discloses an insulin gel composition, characterized in that the gel composition contains insulin, phospholipid, ionic surfactant and gel matrix, and the gel composition is in a liquid state above 32 DEG C or is dissolved or melted into a liquid state within 1 hour. The insulin gel composition of the present application has simple and convenient preparation process, can effectively improve the drug stability, and has a drug release amount of more than 50% within 30 min under the condition of body temperature, and has high relative bioavailability of oral mucosa drug delivery pharmacology.

Description

Technical Field

[0001] This invention relates to an insulin gel composition, belonging to the field of pharmaceutical preparation technology. Background Technology

[0002] Vesicles, also known as liposomes, are spherical or ellipsoidal microparticles formed from amphiphilic phospholipids, possessing a closed bilayer structure and an internal water cavity. The vesicle wall is a bilayer structure composed of lipid molecules. Hydrophilic drugs can be encapsulated in the internal water cavity, while amphiphilic drugs, lipophilic drugs, and charged hydrophilic drugs can bind to the vesicle bilayer through hydrophobic or electrostatic interactions (Critical Issues Related to Transfersomes Novel Vesicular System. Acta Sci. Pol. Technol. Aliment. 2012, 11(1): 67-82). Flexible vesicles, as a type of flexible microparticle, were first proposed by Cevc and Blume in 1992 (Lipid Vesicles Penetrate Into Intact Skin Owing To The Transdermal Osmotic Gradients and Hydration Force. Biochimica Et Biophysica Acta. 1992, 1104(1): 226-232). By adding edge activators to the phospholipid bilayer of the vesicle, the balance of the phospholipid bilayer structure is disrupted, making it elastic and highly deformable. This allows it to be deformed by compression and pass through biomembrane barriers much smaller than its own size, thereby significantly enhancing the absorption of drugs via non-injectable routes of administration. However, because the edge activators added during the preparation of flexible vesicles, while giving them elasticity and deformability, also increase the instability of the bilayer, the drug encapsulation efficiency of flexible vesicles decreases significantly during storage, and the vesicles are prone to aggregation and fusion, affecting the efficacy of the drug and producing side effects. Therefore, flexible vesicles have more severe physical and chemical instability than ordinary vesicles.

[0003] Gels exhibit good biocompatibility, provide sustained and controlled release of drugs, have a simple preparation process, produce aesthetically pleasing shapes, are easy to apply, are readily absorbed after local administration, and demonstrate good stability. Encapsulating microparticles in a gel system can not only modify the drug release profile, but also improve the stability of unstable vesicle-loaded systems (C. Peptu, A.). A. Indrei, M. Popa, New tendencies in controlled drug release-liposomes entrapped in polymer matrices, Rev. Med. Chir. Soc. Med. Nat. Iasi. 113 (2009) 164.).

[0004] As is well known, insulin, as a large protein molecule, has low bioavailability in vivo. Previous studies used an insulin / phospholipid complex as an intermediate carrier and prepared a flexible insulin microparticle by adding an ionic surfactant with edge-activating properties (patent application number 201910392799.6). In vitro and in vivo studies have shown that although the flexible insulin microparticles significantly improve oral mucosal permeability and have relatively high bioavailability for oral mucosal administration, showing good development prospects, the fluidity of the liquid makes it difficult for the insulin flexible microparticle solution to remain at the administration site for an extended period. Therefore, we added a gel matrix to the insulin flexible microparticle solution to increase the bioadhesion of the formulation and thus increase the drug residence time. According to literature reports, the drug release mechanism of gels depends on the solubility of the gel matrix and the diffusion rate of the drug in the gel layer (Dimensional changes, gel layer evolution and drug release studies in hydrophilic matrices loaded with drugs of different solubility[J].Int Jpharm,2007,339(1-2):66-75.). Different drugs have different solubilities, molecular weights, and lipophilicities, resulting in different actual diffusion rates in the gel layer. Furthermore, flexible microparticles, acting as drug reservoirs, encapsulate insulin within them; different gel matrix materials also affect the release rate of insulin within these flexible microparticles.

[0005] Our research found that when insulin gel compositions are prepared using a gel matrix to achieve a certain degree of bioadhesion, it is difficult for the gel composition to simultaneously meet the requirements of efficacy and storage stability: liquid gel compositions can rapidly release drugs during use and have good in vivo efficacy, but most have poor stability, for example, obvious insulin precipitation can be seen after one month of storage in a 4°C refrigerator; semi-solid gel compositions have good stability under storage conditions, but it is difficult to release the drug from the gel during use, resulting in a significant reduction in relative bioavailability in vivo. Summary of the Invention

[0006] The technical problem solved by this invention is to provide an insulin gel composition that can rapidly dissolve or melt at body temperature, quickly releasing the drug from the gel, maintaining its efficacy in vivo, and exhibiting good stability. To solve this technical problem, this invention provides the following technical solution:

[0007] The first aspect of the technical solution of this invention is to provide an insulin gel composition, characterized in that the gel composition contains insulin, phospholipids, an ionic surfactant, and a gel matrix, and the gel composition is in a liquid state above 32°C or dissolves or melts into a liquid state within 1 hour. Herein, the term "liquid state" as used in this invention has a meaning known to those skilled in the art; specifically, "liquid state" refers to a state without a definite shape, in a flowing state, and whose volume remains constant under constant pressure and temperature. For example, "dissolving" in this invention refers to the process of one substance (solute) being dispersed in another substance (solvent) to form a solution. For instance, in this invention, "dissolving" can be the process of an insulin gel being dispersed in water (or animal body fluids) to form a solution. "Melting" in this invention refers to the process of a substance changing from a solid state to a liquid state. The storage conditions or temperature described in this invention are preferably below 30°C, optionally below 25°C, and further optionally below 4°C. The "semi-solid" state in this invention refers to a state between a solid and a liquid, similar to a solid in maintaining its shape and supporting its own weight, while its shape can be changed by pressure, and its ability to flow under low pressure is similar to that of a liquid. In this invention, "room temperature" refers to any temperature or temperature range between 10°C and 30°C. Those skilled in the art will understand that the temperatures used in this invention, such as storage temperatures, animal or human body temperatures, are based on the listed values ​​and may fluctuate by ±1°C. The insulin gel composition of this invention can effectively maintain the in vivo efficacy of the drug and improve its stability, ensuring that its properties do not change during storage.

[0008] The insulin gel composition of the present invention contains a gel matrix with a mass percentage greater than or equal to 0.2% and less than 50%. The gel matrix is ​​selected from one or more of carbomer, cellulose derivatives, hyaluronic acid, alginate, poloxamer, polyvinyl alcohol, polyethylene glycol, polyvinylpyrrolidone, gelatin, scutellaria gum, xanthan gum, and poly-N-acryloylglycine. Preferably, the cellulose derivative is selected from one or more of sodium carboxymethyl cellulose (CMC-Na), hydroxypropyl methylcellulose (HPMC), chitosan, and methylcellulose.

[0009] Preferably, the gel matrix is ​​carbomer, with a percentage content of 0.2% or higher and less than 2.5%, preferably 0.6-2.2%, more preferably 0.7-2%, and even more preferably 0.8-1.8%.

[0010] Preferably, the gel matrix is ​​selected from gelatin and / or hyaluronic acid, with a percentage content of 1-5%, preferably 1-3%.

[0011] Preferably, the gel matrix is ​​a cellulose derivative with a percentage content of 2-6%, more preferably 2.2-5.5%.

[0012] Preferably, the gel matrix is ​​poloxamer, with a percentage content of more than 15% and less than 50%, preferably 20-45%.

[0013] The insulin gel composition of the present invention contains an insulin mass fraction greater than 0.06%, preferably greater than 0.15%.

[0014] The insulin is selected from at least one of animal insulin, human insulin, and insulin analogs.

[0015] The phospholipid is selected from at least one of natural phospholipids and synthetic phospholipids. The ionic surfactant is selected from at least one of bile salts, higher fatty acid salts, sulfates, sulfonates, hexadecyltrimethylamine bromide, and glycyrrhizates.

[0016] The insulin is present in the gel composition in the form of flexible microparticles. Further, the flexible microparticles contain an insulin / phospholipid complex and an ionic surfactant.

[0017] Furthermore, in the flexible microparticles, the mass ratio of insulin, phospholipids, and ionic surfactants is 1:3-50:0.1-20, preferably 1:5-15:0.5-15, and more preferably 1:7-12:1-5.

[0018] Optionally, the flexible microparticles may also contain one or more of free phospholipids, nonionic surfactants, and cholesterol.

[0019] Furthermore, the nonionic surfactant is selected from at least one of Tween surfactants, Span surfactants, poloxamer, fatty acid glycerides, meropenem, and benzyl ester.

[0020] Preferably, the mass ratio of the nonionic surfactant to insulin is 0.1:1 to 20:1, more preferably 2:1 to 15:1;

[0021] Preferably, the mass ratio of the free phospholipid to insulin is 0:1 to 50:1, more preferably 0:1 to 20:1;

[0022] Preferably, the mass ratio of cholesterol to insulin is 0:1 to 10:1, more preferably 0:1 to 1:1.

[0023] The temperature or content ranges disclosed in this invention are expressed in the form of upper and lower limits, which can be one or more lower limits or one or more upper limits, respectively. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. All ranges that can be defined in this way are inclusive and combinable, that is, any lower limit can be combined with any upper limit to form a range. For example, if a range of 1-40 and 0.6-50 is listed for a specific parameter, it is understood that the ranges of 0.6-40 and 1-50 are also expected. Furthermore, if the minimum range values ​​of 1 and 0.5 are listed, and if the maximum range values ​​of 50, 40 and 30 are listed, then the following ranges are all expected: 1-30, 1-40, 1-50, 0.5-30, 0.5-40, 0.5-50.

[0024] Unless otherwise stated, the mass percentages involved in this invention are based on the total mass of the composition.

[0025] The second aspect of the present invention provides a method for preparing the insulin gel composition described in the first aspect, the method comprising the following steps:

[0026] (I) Preparation of flexible insulin microparticles

[0027] 1) Preparation of insulin / phospholipid complex

[0028] Insulin was dissolved in an organic solvent containing an appropriate amount of acid, and phospholipids were dissolved in an appropriate amount of organic solvent. The two solutions were mixed and evaporated under reduced pressure in a water bath at a certain temperature. During the evaporation, an appropriate amount of organic solvent was added in portions, and the solvent was removed by evaporation. The mixture was then dried to obtain the insulin / phospholipid complex.

[0029] 2) The "flexible microparticle solution" for preparing insulin flexible microparticles can be prepared by any of the following methods:

[0030] Method (A):

[0031] • Thin film: The insulin / phospholipid complex and an ionic surfactant are dissolved together in an organic solvent, the solvent is evaporated, and the film is dried to obtain a thin film;

[0032] • Thin film hydration: Take an appropriate amount of aqueous medium and add it to the dried thin film. Hydrate it at a certain temperature for a certain time. After homogenization, a "vesicle solution" is obtained.

[0033] Method (B):

[0034] • Thin film: The insulin / phospholipid complex is dissolved in an organic solvent, the solvent is evaporated, and the film is dried to obtain a thin film;

[0035] • Thin film hydration: Dissolve an ionic surfactant in an appropriate amount of aqueous medium, add it to the dried thin film, hydrate it at a certain temperature for a certain time, and then homogenize it to obtain a "vesicle solution".

[0036] Method (C):

[0037] • Take insulin phospholipid complex and ionic surfactant, dissolve them together in an organic solvent, then add an aqueous medium, sonicate to form an emulsion, remove the organic solvent by rotary evaporation under reduced pressure, and obtain a "vesicle solution".

[0038] Method (D):

[0039] • Dissolve the insulin phospholipid complex in an organic solvent, then dissolve the ionic surfactant in an aqueous medium. Mix and homogenize the two to form an emulsion. Remove the organic solvent by rotary evaporation under reduced pressure to obtain a "vesicle solution".

[0040] (II) Preparation of insulin gel composition

[0041] Take the gel matrix and swell it at a certain temperature. Mix the fully swollen gel matrix with the insulin flexible microparticles from step 2) at a certain temperature and cool it to obtain the final product.

[0042] In one embodiment of the present invention, the method for preparing the gel composition includes the following steps:

[0043] 1) Preparation of insulin / phospholipid complex

[0044] Insulin was dissolved in an organic solvent containing an appropriate amount of acid, and phospholipids were dissolved in an appropriate amount of organic solvent. The two solutions were mixed and evaporated under reduced pressure in a water bath at a certain temperature. During the evaporation, an appropriate amount of organic solvent was added in portions, and the solvent was removed by evaporation. The mixture was then dried to obtain the insulin / phospholipid complex.

[0045] 2) The "flexible microparticle solution" for preparing insulin flexible microparticles can be prepared by any of the following methods: Method (A):

[0046] • Thin film: The insulin / phospholipid complex and ionic surfactant are dissolved together in an organic solvent.

[0047] The solvent is evaporated, and the film is dried to obtain a thin film.

[0048] • Thin film hydration: Take the gel matrix and aqueous medium, add them to the dried thin film, hydrate and swell at a certain temperature for a certain time, and then homogenize to prepare the insulin gel composition.

[0049] Method (B):

[0050] • Thin film: The insulin / phospholipid complex is dissolved in an organic solvent, the solvent is evaporated, and the film is dried to obtain a thin film;

[0051] • Thin film hydration: Dissolve the ionic surfactant in an appropriate amount of aqueous medium, take the gel matrix, add the aqueous medium containing the ionic surfactant and the gel matrix together to the dried film, hydrate and swell at a certain temperature for a certain time, and obtain the insulin gel composition after homogenization.

[0052] Method (C):

[0053] • Take the insulin phospholipid complex and the ionic surfactant, dissolve them together in an organic solvent, take the gel matrix, add it to an aqueous medium, mix the two solutions, sonicate to form an emulsion, remove the organic solvent by rotary evaporation under reduced pressure, and obtain the insulin gel composition.

[0054] Method (D):

[0055] • Dissolve the insulin phospholipid complex in an organic solvent, then add the ionic surfactant and gel matrix to an aqueous medium, mix and homogenize to form an emulsion, and remove the organic solvent by rotary evaporation under reduced pressure to obtain the insulin gel composition.

[0056] In one embodiment, the preparation method of the insulin gel composition of the present invention includes the following steps:

[0057] 1) Preparation of flexible insulin microparticles: prepared by thin-film dispersion method, containing insulin, phospholipids, surfactants and aqueous media;

[0058] 2) Preparation of insulin gel composition:

[0059] Take the gel matrix, swell it at a certain temperature, mix the fully swollen gel matrix with the insulin flexible microparticles from step 1), and cool it to obtain the final product.

[0060] In another embodiment, the method for preparing the insulin gel composition of the present invention includes the following steps:

[0061] Prepared using a thin-film dispersion method, it contains insulin, phospholipids, surfactants, and an aqueous medium containing a gel matrix.

[0062] Beneficial technical effects: The insulin gel composition of the present invention has the following advantages:

[0063] 1) The preparation process is simple and convenient;

[0064] 2) Good stability;

[0065] 3) Under body temperature conditions, the drug release rate reaches more than 50% within 1 hour, and the relative bioavailability of oral mucosal administration is high. Attached Figure Description

[0066] Figure 1 The in vivo blood glucose lowering curve of the insulin liquid gel composition prepared in this invention is shown.

[0067] Figure 2 This is an in vivo blood glucose lowering curve of the insulin-poorly soluble (melting) semi-solid gel composition prepared according to the present invention. Detailed Implementation

[0068] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Through these exemplary descriptions, the features and advantages of the present invention will become clearer and more apparent. Any embodiment described herein as an example is not necessarily to be construed as superior to or better than other embodiments. Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0069] In this invention, the method for determining dissolution or melting time and release amount is as follows: Take 1g of the insulin flexible microparticle gel composition, place it in a 100mL beaker, spread it evenly at the bottom, add 50mL of water, and shake at 37℃ with a rotation speed of 120rpm. Observe the dissolution or melting time. After 30min, transfer an appropriate amount of solution as the test solution for release determination. Separately, accurately weigh an appropriate amount of insulin reference standard, dissolve it in 0.1% trifluoroacetic acid-water solution, and dilute it to a concentration of 100μg / mL as the reference solution. Accurately inject the test solution and the reference solution into the liquid chromatograph for separation and analysis. The chromatographic column is 300SB-C18 (4.6×250mm, 5μm, Agilent), the mobile phase is 0.2mol / L sulfate buffer-acetonitrile (74-26), the flow rate is 1.0mL / min, the detection wavelength is 214nm, the column temperature is 40℃, and the injection volume is 20μL. Record the chromatogram and calculate the insulin release based on the peak area using the external standard method.

[0070] Example 1: Using insulin-phospholipid complex as an intermediate carrier, flexible microparticles loaded with insulin were prepared.

[0071] According to the method described in invention patent application 201180002259.4, 60 mg of insulin was taken, and insulin and phospholipids were added at a mass ratio of 1:10. The mixture was prepared as follows: 60 mg of insulin was dissolved in 6 mL of methanol solution containing 0.1% trifluoroacetic acid; 600 mg of soybean lecithin was dissolved in 54 mL of dichloromethane. The two solutions were mixed to form a clear solution. This solution was subjected to rotary evaporation under reduced pressure at 37°C until the solvent evaporated. The solution was then placed in a vacuum drying oven and dried, scraped into a sealed container to obtain the insulin / phospholipid complex. 660 mg of the insulin / phospholipid complex, along with 600 mg of free phospholipids and 400 mg of Tween 20, was dissolved in 20 mL of dichloromethane to form a clear solution. This solution was subjected to rotary evaporation under reduced pressure at 37°C until the solvent evaporated, yielding a dried film. 100 mg of sodium deoxycholate was dissolved in 20 mL of phosphate buffer (0.02 mol / L) to obtain sodium deoxycholate phosphate buffer. The resulting film was hydrated with this sodium deoxycholate phosphate buffer for 30 min. After hydration, the film was ultrasonically dispersed (150 W, 1 min / time, 4 times) and passed through a membrane (0.22 μm) to obtain flexible microparticles with an insulin / phospholipid complex as the intermediate carrier and a particle size of 81 nm.

[0072] Example 2: Take a fully swollen gel matrix (0.5 g of carbomer (0.5% by mass) in 50 mL of water; after complete swelling, add ethanolamine to adjust the pH to between 6.5 and 7.5), and mix an appropriate amount with the same weight of insulin flexible microparticles from Example 1. Vortex for 30 seconds, centrifuge the prepared gel at 3000 rpm for 20 min to fully degas, and obtain the insulin flexible microparticle gel composition. This gel is in a liquid state when stored in a refrigerator (4°C) and at room temperature (20-25°C). At 37°C, it dissolves or melts within 30 min, with a release rate of 83% within 30 min. After resolvation, the particle size is 106 nm.

[0073] Example 3: Take a fully swollen gel matrix (2.5g of carbomer (2.5% by mass) in 50mL of water; after complete swelling, add ethanolamine to adjust the pH to between 6.5 and 7.5). Take an appropriate amount and mix thoroughly with the same weight of insulin flexible microparticles from Example 1. Vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition. This gel is in a semi-solid state when stored under refrigeration (4℃) and at room temperature (20-25℃). At 37℃, it cannot dissolve or melt within 1 hour, and the release rate is 12% within 30min. After reconstitution, the particle size is 132nm.

[0074] Example 4: Take the fully swollen gel matrix (4g of sodium carboxymethyl cellulose (4% by mass) in 50mL of water, let it swell by standing), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition. This gel is in a semi-solid state when stored under refrigeration (4℃) and at room temperature (20-25℃). At 37℃, it can dissolve or melt within 30min, with a release rate of 95% within 30min. After resolvation, the particle size is 316nm.

[0075] Example 5: Take the fully swollen gel matrix (4g of hydroxypropyl methylcellulose (4% by mass) in 50mL of water, let it swell by standing), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition. This gel is in a semi-solid state when stored under refrigeration (4℃) and at room temperature (20-25℃). At 37℃, it can dissolve or melt within 1 hour, and the release rate is 67% within 30min. The particle size after resolvation is 94nm.

[0076] Example 6: Take a fully swollen gel matrix (2g of hyaluronic acid (2% by mass) in 50mL of water, let it swell by standing), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain an insulin flexible microparticle gel composition. This gel is in a semi-solid state when refrigerated (4℃), stored at room temperature (20-25℃), and at 30℃. At 37℃, it can dissolve or melt within 30min, with a release rate of 90% within 30min. After resolvation, the particle size is 127nm.

[0077] Example 7: Take the fully swollen gel matrix (take 80 mg of gelatin (2% by mass), add 2 mL of water, heat until dissolved, and let stand at about 37°C), mix it evenly with the same weight of insulin flexible microparticles from Example 1, and let stand at room temperature to obtain an insulin flexible microparticle gel composition. This gel is in a liquid state when stored at room temperature (20-25°C), and in a semi-solid state when stored in a refrigerator (4°C). At 37°C, it dissolves or melts within 30 minutes, with a release rate of 92% within 30 minutes. After reconstitution, the particle size is 84 nm.

[0078] Example 8: Take a fully swollen gel matrix (0.1 g of carbomer (0.1% by mass) in 50 mL of water; after complete swelling, add ethanolamine to adjust the pH to between 6.5 and 7.5), take an appropriate amount and mix thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000 rpm for 20 min to fully degas, and obtain the insulin flexible microparticle gel composition. This gel is in a liquid state when stored in a refrigerator (4°C) and at room temperature (20-25°C), and can dissolve or melt within 30 min at 37°C.

[0079] Example 9: Take a fully swollen gel matrix (0.2 g of carbomer (0.2% by mass) in 50 mL of water; after complete swelling, add ethanolamine to adjust the pH to between 6.5 and 7.5), take an appropriate amount and mix thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000 rpm for 20 min to fully degas, and obtain the insulin flexible microparticle gel composition. This gel is in a liquid state when stored in a refrigerator (4°C) and at room temperature (20-25°C), and can dissolve or melt within 30 min at 37°C.

[0080] Example 10: Take a fully swollen gel matrix (2.2 g of carbomer (2.2% by mass) in 50 mL of water; after complete swelling, add ethanolamine to adjust the pH to between 6.5 and 7.5), take an appropriate amount and mix thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000 rpm for 20 min to fully degas, and obtain the insulin flexible microparticle gel composition. This gel is in a semi-solid state when stored in a refrigerator (4°C) and at room temperature (20-25°C), and dissolves or melts within 1 hour at 37°C.

[0081] Example 11: Take a fully swollen gel matrix (1 g of carbomer (1% by mass) in 50 mL of water; after complete swelling, add ethanolamine to adjust the pH to between 6.5 and 7.5), take an appropriate amount and mix thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000 rpm for 20 min to fully degas, and obtain the insulin flexible microparticle gel composition. This gel is semi-solid when stored under refrigeration (4°C) and at room temperature (20-25°C), and can dissolve or melt within 1 hour at 37°C.

[0082] Example 12: Take a fully swollen gel matrix (2.5g chitosan (2.5% by mass) in 50mL of water, add an appropriate amount of glacial acetic acid to dissolve the chitosan, then add an appropriate amount of sodium glycerophosphate, and swell completely at 4°C), take an appropriate amount and mix thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition. This gel is in a liquid state when stored in a refrigerator (4°C), in a semi-solid state when stored at room temperature (20-25°C), and can dissolve or melt within 30min at 37°C.

[0083] Example 13: Take a fully swollen gel matrix (15g of poloxamer (15% by mass) in 50mL of water, swollen completely at 4°C), take an appropriate amount and mix thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition. This gel is in a liquid state when stored in a refrigerator (4°C) and in a liquid state when stored at room temperature (20-25°C).

[0084] Example 14: Take a fully swollen gel matrix (30g of poloxamer (30% by mass) in 50mL of water, swollen completely at 4°C), and mix an appropriate amount with the same weight of insulin flexible microparticles from Example 1. Vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition. This gel is in a liquid state when stored in a refrigerator (4°C), and in a semi-solid state when stored at room temperature (20-25°C). It can dissolve or melt within 1 hour at 37°C.

[0085] Example 15: Take a fully swollen gel matrix (50g of poloxamer (50% by mass) dissolved in 50mL of water, swollen completely at 4°C), and mix an appropriate amount with the same weight of insulin flexible microparticles from Example 1. Vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition. This gel is in a liquid state when stored in a refrigerator (4°C), and in a semi-solid state when stored at room temperature (20-25°C). It does not dissolve or melt within 1 hour at 37°C.

[0086] Example 16: Take the fully swollen gel matrix (take 80 mg of agarose (2% by mass), add 2 mL of water, heat to dissolve, and let stand at about 37°C), mix it evenly with the same weight of insulin flexible microparticles from Example 1, and let stand at room temperature to obtain an insulin flexible microparticle gel composition. This gel is in a semi-solid state when stored in a refrigerator (4°C) or at room temperature (20-25°C), and does not dissolve or melt within 1 hour at 37°C.

[0087] Example 17: Take the fully swollen gel matrix (take 120 mg of carrageenan (3% by mass), add 2 mL of water, heat to dissolve, and let stand at approximately 37°C), mix it evenly with the same weight of insulin flexible microparticles from Example 1, and let stand at room temperature to obtain an insulin flexible microparticle gel composition. This gel is in a semi-solid state when stored in a refrigerator (4°C) or at room temperature (20-25°C), and does not dissolve or melt within 1 hour at 37°C.

[0088] Example 18: Take the fully swollen gel matrix (take 40 mg of carrageenan (1% by mass), add 2 mL of water, heat to dissolve, and let stand at approximately 37°C), mix it evenly with the same weight of the insulin flexible microparticles from Example 1, and let stand at room temperature to obtain the insulin flexible microparticle gel composition. This gel is in a semi-solid state when stored in a refrigerator (4°C) or at room temperature (20-25°C), and does not dissolve or melt within 1 hour at 37°C.

[0089] Example 19: Take the fully swollen gel matrix (take 10 mg of carrageenan (0.25% by mass), add 2 mL of water, heat to dissolve, and let stand at about 37°C), mix it evenly with the same weight of insulin flexible microparticles from Example 1, and let stand at room temperature to obtain an insulin flexible microparticle gel composition. This gel is in a liquid state when stored under refrigeration (4°C) and at room temperature (20-25°C).

[0090] Example 20: Take 80 mg of gelatin (2% by mass) and add it to 2 mL of the phosphate buffer solution from Example 1. Hydrate for 30 min and mix thoroughly to obtain an insulin gel composition. The gel is in a liquid state when stored at room temperature (20-25°C) and in a semi-solid state when stored in a refrigerator (4°C). It can dissolve or melt within 30 min at 37°C.

[0091] Example 21: Take the fully swollen gel matrix (40 mg gelatin, 80 mg hyaluronic acid, 2 mL water, heated until dissolved, and then allowed to stand at approximately 37°C), mix it evenly with the same weight of the insulin flexible microparticles from Example 1, and allow it to stand at room temperature to obtain the insulin flexible microparticle gel composition. This gel is semi-solid when stored under refrigeration (4°C) and at room temperature (20-25°C), and dissolves or melts within 30 minutes at 37°C.

[0092] Example 22: Take the fully swollen gel matrix (60 mg gelatin, 60 mg hyaluronic acid, 2 mL water, heated until dissolved, and then allowed to stand at approximately 37°C), mix it evenly with the same weight of the insulin flexible microparticles from Example 1, and allow it to stand at room temperature to obtain the insulin flexible microparticle gel composition. This gel is semi-solid when stored under refrigeration (4°C) and at room temperature (20-25°C), and dissolves or melts within 30 minutes at 37°C.

[0093] Example 23: Take the fully swollen gel matrix (80 mg gelatin, 40 mg hyaluronic acid, 2 mL water, heated until dissolved, and then allowed to stand at approximately 37°C), mix it evenly with the same weight of the insulin flexible microparticles from Example 1, and allow it to stand at room temperature to obtain the insulin flexible microparticle gel composition. This gel is semi-solid when stored under refrigeration (4°C) and at room temperature (20-25°C), and dissolves or melts within 30 minutes at 37°C.

[0094] Example 24: Take the fully swollen gel matrix (96 mg of gelatin, 24 mg of hyaluronic acid, 2 mL of water, heated until dissolved, and then allowed to stand at approximately 37°C), mix it evenly with the same weight of the insulin flexible microparticles from Example 1, and allow it to stand at room temperature to obtain the insulin flexible microparticle gel composition. This gel is semi-solid when stored under refrigeration (4°C) and at room temperature (20-25°C), and dissolves or melts within 30 minutes at 37°C.

[0095] Example 25: Take a fully swollen gel matrix (take 0.6 g of carbomer (mass percentage of 0.6%) in 50 mL of water, and after it has swollen completely, add ethanolamine to adjust the pH to between 6.5 and 7.5), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000 rpm for 20 min to fully degas, and obtain the insulin flexible microparticle gel composition.

[0096] Example 26: Take a fully swollen gel matrix (take 0.7g of carbomer (mass percentage of 0.7%) in 50mL of water, and after it has swollen completely, add ethanolamine to adjust the pH to between 6.5 and 7.5), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition.

[0097] Example 27: Take a fully swollen gel matrix (take 0.8g of carbomer (mass percentage of 0.8%) in 50mL of water, and after it has swollen completely, add ethanolamine to adjust the pH to between 6.5 and 7.5), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition.

[0098] Example 28: Take the fully swollen gel matrix (take 2g of carbomer (2% by mass) in 50mL of water, and after it has swollen completely, add ethanolamine to adjust the pH to between 6.5 and 7.5), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition.

[0099] Example 29: Take a fully swollen gel matrix (take 1.8g of carbomer (mass percentage of 1.8%) in 50mL of water, and after it has swollen completely, add ethanolamine to adjust the pH to between 6.5 and 7.5), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition.

[0100] Example 30: Take the fully swollen gel matrix (take 1g of hyaluronic acid (mass percentage of 1%) in 50mL of water and let it swell by standing), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition.

[0101] Example 31: Take the fully swollen gel matrix (take 3g of hyaluronic acid (mass percentage of 3%) in 50mL of water and let it stand to swell), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition.

[0102] Example 32: Take the fully swollen gel matrix (take 5g of hyaluronic acid (mass percentage of 5%) in 50mL of water and let it swell by standing), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas it, and obtain the insulin flexible microparticle gel composition.

[0103] Example 33: Take the fully swollen gel matrix (take 40 mg of gelatin (1% by mass), add 2 mL of water, heat until dissolved, and let stand at approximately 37°C), mix it evenly with the same weight of the insulin flexible microparticles from Example 1, and let stand at room temperature to obtain the insulin flexible microparticle gel composition. This gel is in a liquid state when stored at room temperature (20-25°C), and in a semi-solid state when refrigerated (4°C). It can dissolve or melt within 30 minutes at 37°C.

[0104] Example 34: Take the fully swollen gel matrix (take 120 mg of gelatin (3% by mass), add 2 mL of water, heat until dissolved, and let stand at about 37°C), mix it evenly with the same weight of insulin flexible microparticles from Example 1, and let stand at room temperature to obtain an insulin flexible microparticle gel composition. This gel is in a semi-solid state when stored at room temperature (20-25°C) and refrigerated (4°C), and can dissolve or melt within 30 minutes at 37°C.

[0105] Example 35: Take the fully swollen gel matrix (take 200 mg of gelatin (5% by mass), add 2 mL of water, heat until dissolved, and let stand at approximately 37°C), mix it evenly with the same weight of the insulin flexible microparticles from Example 1, and let stand at room temperature to obtain the insulin flexible microparticle gel composition. This gel is semi-solid when stored at room temperature (20-25°C) and refrigerated (4°C), and dissolves or melts within 1 hour at 37°C.

[0106] Example 36: Take the fully swollen gel matrix (take 2g of sodium carboxymethyl cellulose (mass percentage of 2%) in 50mL of water and let it swell by standing), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition.

[0107] Example 37: Take the fully swollen gel matrix (take 2.2g of sodium carboxymethyl cellulose (mass percentage of 2.2%) in 50mL of water and let it swell by standing), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition.

[0108] Example 38: Take the fully swollen gel matrix (take 5.5g of sodium carboxymethyl cellulose (mass percentage of 5.5%) in 50mL of water and let it swell by standing), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition.

[0109] Example 39: Take the fully swollen gel matrix (take 6g of sodium carboxymethyl cellulose (mass percentage of 6%) in 50mL of water and let it stand to swell), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas, and obtain the insulin flexible microparticle gel composition.

[0110] Example 40: Take the fully swollen gel matrix (take 20g of poloxamer (mass percentage of 20%) in 50mL of water and swell it completely at 4℃), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas it, and obtain the insulin flexible microparticle gel composition.

[0111] Example 41: Take the fully swollen gel matrix (take 45g of poloxamer (mass percentage of 45%) in 50mL of water and swell it completely at 4℃), take an appropriate amount and mix it thoroughly with the same weight of insulin flexible microparticles from Example 1, vortex for 30 seconds, centrifuge the prepared gel at 3000rpm for 20min to fully degas it, and obtain the insulin flexible microparticle gel composition.

[0112] Example 42: Preparation of gel compositions of different insulin flexible microparticles

[0113] (1) Preparation of insulin / phospholipid complex

[0114] Take 60 mg of insulin and add it to phospholipids at mass ratios of 1:3, 1:5, 1:10, 1:20, and 1:50 as follows: Dissolve 60 mg of insulin in 6 mL of methanol solution containing 0.1% trifluoroacetic acid; dissolve 180 mg, 300 mg, 600 mg, 1200 mg, and 3000 mg of soybean lecithin in 54 mL of dichloromethane. Mix the two solutions to form a clear solution. Evaporate this solution under reduced pressure at 37 °C until the solvent evaporates completely. Place it in a vacuum drying oven, dry it, and scrape it into a sealed container to obtain a series of insulin phospholipid complexes, labeled as complexes I, II, III, IV, and V.

[0115] (2) Prepare insulin flexible microparticles according to the following method

[0116] Method 1

[0117] Thin film: The insulin / phospholipid complex III, Tween 20, sodium deoxycholate and free phospholipid prepared in (1) were dissolved together in chloroform:methanol (3:1), the solvent was evaporated and dried to obtain a thin film;

[0118] Membrane hydration: Take an appropriate amount of phosphate buffer (0.02 mol / L) and add it to the dried membrane. Hydrate for 30 min. After hydration, disperse the membrane by ultrasonication (150 W, 1 min / time, 4 times in total) and pass it through the membrane (0.22 μm) to obtain insulin flexible microparticles.

[0119] Method 2

[0120] Thin film: The insulin / phospholipid complex III, Tween 20, free phospholipids and cholesterol prepared in (1) were dissolved together in dichloromethane, the solvent was evaporated and dried to obtain a thin film;

[0121] Membrane hydration: Sodium deoxycholate was added to phosphate buffer (0.02 mol / L) and then added to the dried membrane. Hydration was carried out for 30 min. After hydration, the membrane was ultrasonically dispersed (150 W, 1 min / time, 4 times in total) and passed through the membrane (0.22 μm) to obtain insulin flexible microparticles.

[0122] Method 3

[0123] Thin film: The insulin / phospholipid complex III and free phospholipids prepared in (1) were dissolved in dichloromethane, the solvent was evaporated, and the film was dried to obtain a thin film;

[0124] Membrane hydration: Tween20 and sodium deoxycholate were dissolved in 20 mL of phosphate buffer (0.02 mol / L) to obtain the surfactant phosphate buffer, which was added to the membrane and hydrated for 30 min. After hydration, the membrane was ultrasonically dispersed (150 W, 1 min / time, 4 times in total) and passed through the membrane (0.22 μm) to obtain insulin flexible microparticles.

[0125] Method 4

[0126] The insulin / phospholipid complex III, free phospholipids, Tween 20 and sodium deoxycholate prepared in (1) were dissolved together in chloroform:methanol (3:1), 20 mL of phosphate buffer (0.02 mol / L) was added, and the mixture was sonicated to form an emulsion. The organic solvent was removed by rotary evaporation under reduced pressure to obtain flexible microparticles.

[0127] Insulin flexible microparticles were prepared according to the above method, and insulin gel compositions were prepared according to the methods in the examples, as detailed in the table below:

[0128] Table 1. Composition and preparation of different insulin gel compositions

[0129]

[0130]

[0131] Similar results can be obtained by replacing it with any insulin / phospholipid complex.

[0132] Example 43: Preparation of an insulin flexible microparticle gel composition using insulin as an intermediate carrier

[0133] 1.2 g of free phospholipids and 400 mg of Tween 20 were dissolved together in 20 mL of dichloromethane and evaporated to dryness to obtain a dried film. 60 mg of insulin and 100 mg of sodium deoxycholate were dissolved in 20 mL of phosphate buffer (0.02 mol / L) and added to the film. The mixture was hydrated for 30 min. After hydration, the mixture was ultrasonically dispersed (150 W, 1 min / time, 4 times) and passed through a membrane (0.22 μm) to obtain flexible insulin microparticles. The method of Example 7 was used to prepare the flexible insulin microparticle gel composition. The gel was liquid when stored at room temperature (20-25 °C), semi-solid when refrigerated (4 °C), and dissolved or melted within 30 min at 37 °C.

[0134] Test case

[0135] Experimental Example 1: Experiments on insulin flexible microparticle liquid gel and insulin flexible microparticle poorly soluble (melting) semi-solid gel.

[0136] The insulin flexible microparticle liquid gel and the insulin flexible microparticle poorly soluble (melting) semi-solid gel prepared in Examples 2 and 3 were used to investigate their properties, particle size, dissolution or melting time and release amount within 30 min.

[0137] Methods for determining dissolution or melting time and release amount: Take 1g of insulin flexible microparticle gel composition, place it in a 100mL beaker, spread it evenly at the bottom, add 50mL of water, and shake at 37℃ with a rotation speed of 120rpm. Observe the dissolution or melting time. After 30min, transfer an appropriate amount of solution as the test solution for release determination. Separately, accurately weigh an appropriate amount of insulin reference standard, dissolve it in 0.1% trifluoroacetic acid-water solution, and dilute it to a concentration of 100μg / mL as the reference solution. Accurately inject the test solution and the reference solution into the liquid chromatograph for separation and analysis. The chromatographic column is 300SB-C18 (4.6×250mm, 5μm, Agilent), the mobile phase is 0.2mol / L sulfate buffer-acetonitrile (74-26), the flow rate is 1.0mL / min, the detection wavelength is 214nm, the column temperature is 40℃, and the injection volume is 20μL. Record the chromatogram and calculate the insulin release based on the peak area using the external standard method.

[0138] Table 2. In vitro release of two types of insulin flexible microparticle gels

[0139]

[0140] The experimental results show that, compared with the insulin flexible microparticle liquid gel, the insulin flexible microparticle poorly soluble semi-solid gel is difficult to dissolve or melt rapidly within 1 hour at 37℃, with a drug release of only 12% in 30 minutes. In contrast, the insulin flexible microparticle liquid gel can dissolve or melt rapidly within 30 minutes, with a release of up to 83% in 30 minutes. Therefore, there is a positive correlation between dissolution or melting time and the release amount in 30 minutes; the faster the dissolution or melting, the higher the release amount in 30 minutes.

[0141] Experimental Example 2: In vivo hypoglycemic effect of insulin flexible microparticle liquid gel

[0142] 1) Test drug

[0143] Insulin solution: Insulin solution (87 IU / ml);

[0144] Insulin flexible microparticles: Insulin flexible microparticles (87 IU / ml) prepared according to Example 1;

[0145] Insulin flexible microparticle liquid gel: Insulin flexible microparticle gel composition (43.5 IU / g) prepared according to Example 2.

[0146] 2) Experimental animals and rabbit esophageal ligation model

[0147] Healthy male Japanese white rabbits, weighing 2.0 ± 0.5 kg, were used. After fasting for 2 hours (water was allowed), initial blood glucose levels were measured using a Johnson & Johnson OneHop blood glucose meter. Animals with initial blood glucose levels between 6.0 and 10.0 mmol / L were anesthetized by intravenous injection of 2% sodium pentobarbital. The esophagus was then ligated. Administering the medication was done 10 minutes after the blood glucose level stabilized. The esophageal ligation was removed half an hour after administration, and the wound was sutured.

[0148] 3) Administration method and dosage

[0149] Twelve Japanese white rabbits with esophageal ligation were randomly divided into four groups of three rabbits each, and administered the drugs according to the following administration method and dosage.

[0150] Insulin solution group: Administered sublingually and buccally (38.70~39.54℃), 10 IU / kg. Divide the total dose of the drug solution into 4 equal parts. Take one part of each part and drip it evenly onto both buccal mucosa. Take two parts and drip them evenly under the tongue.

[0151] Subcutaneous injection group: Insulin solution was administered subcutaneously at a rate of 1 IU / kg;

[0152] Insulin flexible microparticle group: administration method is the same as insulin solution group;

[0153] Insulin flexible microparticle liquid gel group: administered sublingually and buccally, 10 IU / kg. The entire dose of gel was divided into 4 equal parts. One part of each part was evenly applied to both buccal mucosa, and two parts were evenly applied to the sublingual area.

[0154] 4) Blood glucose measurement

[0155] Blood samples were collected from the marginal ear vein at 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, and 6 hours after administration. Blood glucose levels were measured and recorded using a glucometer. The average percentage reduction in blood glucose for each group was calculated, and a blood glucose reduction curve after a single administration was plotted.

[0156] 5) Test Results

[0157] Test results ( Figure 1 The results showed that oral mucosal administration of insulin flexible microparticle liquid gel to Japanese white rabbits with esophageal ligation resulted in a 70% reduction in blood glucose levels compared to the initial blood glucose value; it had the same hypoglycemic effect as insulin flexible microparticles, with a relative bioavailability of 15.40%; it was significantly superior to the insulin solution group administered at the same dose and in the same manner, and had good oral mucosal absorption; compared with subcutaneous injection of insulin solution at a dose of 1 IU / kg, it had a greater hypoglycemic effect and a longer duration of action.

[0158] As can be seen from Experiment 1 and Experiment 2, the insulin flexible microparticle gel that can dissolve or melt rapidly has a high release rate within 30 minutes. On the other hand, due to the increased adhesion, the delivery time of the flexible microparticles at the drug delivery site is prolonged, thereby maintaining the good efficacy of the flexible microparticles.

[0159] Experiment 3: Experiment on the stability of insulin flexible microparticle liquid gel

[0160] The insulin flexible microparticle liquid gels prepared according to Examples 2, 8, and 9 were subjected to a stability test at 4°C.

[0161] Table 3. Stability of Insulin Flexible Microparticle Liquid Gel at 4℃

[0162]

[0163] The experimental results showed that insulin precipitates in the insulin flexible microparticle gel prepared with 0.1% carbomer after one month, while the insulin flexible microparticle gels prepared with 0.2% and 0.5% carbomer are stable within one month and two months, respectively.

[0164] Experimental Example 4: In vivo hypoglycemic experiment on insoluble (melting) semi-solid gel containing insulin flexible microparticles

[0165] 1) Test drug

[0166] Insulin solution: Insulin solution (87 IU / ml);

[0167] Insulin flexible microparticles: Insulin flexible microparticles (87 IU / ml) prepared according to Example 1;

[0168] Insulin flexible microparticle insoluble semi-solid gel: Insulin flexible microparticle gel composition (43.5 IU / g) prepared according to Example 3.

[0169] 2) The experimental animals and the rabbit esophageal ligation model were the same as in Experiment 1.

[0170] 3) Administration method and dosage

[0171] Twelve Japanese white rabbits with esophageal ligation were randomly divided into four groups of three rabbits each, and administered the drugs according to the following administration method and dosage.

[0172] Insulin solution group: Administered sublingually and buccally, 10 IU / kg. Divide the total dose of the solution into 4 equal parts. Take one part of each part and drip it evenly onto both buccal mucosa. Take two parts and drip them evenly under the tongue.

[0173] Subcutaneous injection group: Insulin solution was administered subcutaneously at a rate of 1 IU / kg;

[0174] Insulin flexible microparticle group: administration method is the same as insulin solution group;

[0175] Insulin flexible microparticle insoluble gel group: Administered sublingually and buccally, 10 IU / kg. Divide the total dose of gel into 4 equal parts. Take one part of each part and apply it evenly to both buccal mucosa. Take two parts and apply them evenly to the sublingual area.

[0176] Blood glucose measurement was performed in the same manner as in Case 1.

[0177] 4) Test Results

[0178] Test results ( Figure 2 The results showed that increasing the carbomer concentration to obtain a poorly soluble (melting) semi-solid gel of insulin flexible microparticles significantly reduced the hypoglycemic effect in vivo, with a relative bioavailability of 2.94%. This indicates that the poorly soluble (melting) semi-solid gel of insulin flexible microparticles is difficult to dissolve or melt rapidly within 1 hour, and its release rate after 30 minutes is only 12%, thus reducing its efficacy in vivo.

[0179] Experiment 5: Experiments on different gel matrices

[0180] The insulin flexible microparticles and gel matrix prepared in Example 1 were used to prepare insulin flexible microparticle gel compositions according to Examples 4, 5, 6 and 7, using the commonly used amounts of different gel matrices. Their properties, particle size, dissolution or melting time and release amount within 30 min were investigated.

[0181] Table 4. Effect of different gel matrices on the quality of insulin flexible microparticle gel compositions

[0182]

[0183] The results showed that the insulin flexible microparticle gel composition prepared from sodium carboxymethyl cellulose, hydroxypropyl cellulose, hyaluronic acid, and gelatin was in a semi-solid state at 4°C and / or 20-25°C, with a particle size of less than 400 nm. It could dissolve or melt within 1 hour, and the drug release at 37°C was more than 50%. The dissolution or melting time and the release amount at 30 min were comparable to those of the insulin flexible microparticle liquid gel prepared in Example 2. These results further verified the positive correlation between the dissolution or melting rate and the release amount at 30 min.

[0184] Based on the above results, it can be concluded that if the insulin gel composition can dissolve or melt within 1 hour, its release rate within 30 minutes can reach more than 50%. Therefore, we measured the dissolution or melting time of the gel composition in the examples to examine the level of its release rate.

[0185] Experiment 6: An experiment was conducted on the ratio of gelatin and hyaluronic acid mixed gel matrix.

[0186] The insulin flexible microparticles and gel matrix prepared in Example 1 were used to prepare insulin gel compositions according to the preparation methods of Examples 21, 22, 23, and 24. Their properties and dissolution or melting time were investigated.

[0187] Table 5. Effect of mixed gel matrix on the quality of insulin gel composition

[0188]

[0189] The results showed that the insulin flexible microparticle gel compositions prepared by gelatin and hyaluronic acid in different proportions were in a semi-solid state at 4℃ and / or at room temperature of 20-25℃, and could be dissolved or melted within 30 minutes at 37℃.

[0190] Experiment 7: Experiments on different preparation methods

[0191] The insulin flexible microparticles and gel matrix prepared in Example 1 were used to prepare an insulin gel composition according to the preparation methods of Examples 7 and 20, and its properties and dissolution or melting time were investigated.

[0192] Table 6. Effect of different preparation methods on the quality of insulin gel compositions

[0193]

[0194] The results showed that there was no significant difference between the two preparation methods.

[0195] Experimental Example 8: Stability Test of Semi-Solid Insulin Flexible Microparticle Gel Composition

[0196] The insulin flexible microparticle gel compositions prepared in Examples 7 and 11 were subjected to a stability test at 4°C.

[0197] Table 7. Stability of the insulin flexible microparticle gel composition at 4°C

[0198]

[0199] The results showed that the semi-solid insulin flexible microparticle gel composition was stable at 4°C for 3 months.

[0200] The present invention has been described above with reference to preferred embodiments; however, these embodiments are merely exemplary and illustrative. Various substitutions and modifications can be made to the present invention based on these embodiments, all of which fall within the scope of protection of the present invention.

Claims

1. An insulin gel composition for oral mucosal administration, characterized in that, The gel composition contains flexible microparticles and a gel matrix, and the gel composition is in a liquid state at a temperature above 32°C or dissolves or melts into a liquid state within 1 hour; The gel matrix is ​​carbomer, with a mass percentage of 0.2-2.2%, or The gel matrix is ​​gelatin, with a mass percentage of 1-5%, or The gel matrix is ​​hyaluronic acid, with a mass percentage of 2%, or The gel matrix is ​​gelatin and hyaluronic acid, and the total mass percentage of the gelatin and hyaluronic acid is 3%, or The gel matrix is ​​a cellulose derivative with a mass percentage of 4%, wherein the cellulose derivative is sodium carboxymethyl cellulose or hydroxypropyl methylcellulose, or The gel matrix is ​​poloxamer, with a mass percentage of 15% or 30%; The flexible microparticles contain an insulin / phospholipid complex and an ionic surfactant. The mass ratio of insulin, phospholipid, and ionic surfactant in the flexible microparticles is 1:3 to 50:0.1 to 20. The ionic surfactant is sodium deoxycholate, and the phospholipid is soybean lecithin.

2. The insulin gel composition according to claim 1, characterized in that, The gel matrix is ​​carbomer, with a mass percentage of 0.7-2%.

3. The insulin gel composition according to claim 1, characterized in that, The gel matrix is ​​carbomer, with a mass percentage of 0.8-1.8%.

4. The insulin gel composition according to claim 1, characterized in that, The gel matrix is ​​gelatin, with a mass percentage of 2%.

5. The insulin gel composition according to claim 1, characterized in that, The mass fraction of insulin in the gel composition is greater than or equal to 0.15%.

6. The insulin gel composition according to claim 1, characterized in that, The insulin is selected from at least one of animal insulin, human insulin, and insulin analogs.

7. The insulin gel composition according to claim 1, characterized in that, In the flexible microparticles, the mass ratio of insulin, phospholipids, and ionic surfactants is 1:5-15:0.5-15.

8. The insulin gel composition according to claim 1, characterized in that, In the flexible microparticles, the mass ratio of insulin, phospholipids, and ionic surfactants is 1:7-12:1-5.

9. The insulin gel composition according to claim 1, characterized in that, The flexible microparticles also contain nonionic surfactants and cholesterol.

10. The insulin gel composition according to claim 9, characterized in that, The nonionic surfactant is Tween 20.

11. The insulin gel composition according to claim 9, characterized in that, The mass ratio of the nonionic surfactant to insulin is 0.1:1 to 20:

1. The mass ratio of cholesterol to insulin is 0:1 to 10:

1.

12. The insulin gel composition according to claim 9, characterized in that, The mass ratio of the nonionic surfactant to insulin is 2:1 to 15:1; The mass ratio of cholesterol to insulin is 0:1 to 1:1.

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