Fipronil methoxyprenene temperature-sensitive gel as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of pharmaceutical preparations, and particularly relates to fipronil methoxyprenene temperature-sensitive gel as well as a preparation method and application thereof. The fipronil and metopropene temperature-sensitive gel is prepared from the following components in percentage by weight and volume: 10% of fipronil, 12% of metopropene, 12%-14% of poloxamer 407, 0-0.05% of a stabilizer, 2.5%-7.0% of a penetration enhancer, 28.0%-30.0% of absolute ethyl alcohol, 0.05%-0.1% of a preservative, 0.05%-0.1% of a humectant and the balance of water. The gelation temperature of the temperature-sensitive gel prepared by the invention is 32 + / -1 DEG C, the medicine cumulative permeation amount of the prepared gel is more than 20% of the cumulative permeation amount of medicines in commercially available products, and the fitting transdermal duration of one or two of the methoxyl prene or the fipronil is longer than the fitting transdermal duration of corresponding medicines in commercially available Fulahn.

Description

Technical Field

[0001] The present invention belongs to the technical field of pharmaceutical preparations, and particularly relates to a fipronil-methoprene thermosensitive gel, a preparation method thereof, and an application thereof. Background Art

[0002] Fipronil-methoprene drops is a relatively mature product on the market with the characteristic of killing parasites throughout the life cycle. It is produced by Boehringer Ingelheim, and its Chinese trade name is "Frontline". This preparation is dropped on the skin for use.

[0003] Fipronil-methoprene drops, namely compound fipronil drops, contain 50 mg of fipronil and 60 mg of methoprene per 0.5 ml (for cat drops).

[0004] The existing drops have the disadvantages of a large amount of organic solvents used, burning of hair, high oiliness, and easy loss of drugs, resulting in a significant reduction in drug efficacy. Therefore, finding a new dosage form with a small amount of organic solvents used and enabling the drugs to fully play their roles is an urgent problem for R & D personnel to solve. Summary of the Invention

[0005] In order to overcome the defects of the prior art, the present invention provides a fipronil-methoprene thermosensitive gel. The fipronil-methoprene thermosensitive gel not only has an appropriate gelation temperature and gelation time, has good transdermal permeability, but also has an obvious sustained-release effect, can reduce the loss of drugs, and thus improves the drug efficacy.

[0006] The present invention is realized through the following technical solutions:

[0007] The present invention provides a fipronil-methoprene thermosensitive gel, which includes fipronil, methoprene, poloxamer 407, a stabilizer, a penetration enhancer, a preservative, absolute ethanol, a humectant, and distilled water;

[0008] The weight / volume percentage of each component in the thermosensitive gel is as follows: fipronil 10%, methoprene 12%, poloxamer 407 is 12 - 14%, the stabilizer is 0 - 0.05%, the penetration enhancer is 2.5 - 7.0%, absolute ethanol is 28.0 - 30.0%, the preservative is 0.05 - 0.1%, the humectant is 0.05 - 0.1%, and the balance is water.

[0009] The penetration enhancer is one or a combination of two of 1,2 - propylene glycol, laurocapram, and crotamiton.

[0010] Furthermore, the penetration enhancer is 1,2 - propylene glycol, a combination of 1,2 - propylene glycol and laurocapram, or a combination of 1,2 - propylene glycol and crotamiton.

[0011] When the penetration enhancer is a combination of 1,2 - propylene glycol and laurocapram, the mass ratio of 1,2 - propylene glycol to laurocapram is 2:3 - 4:1, preferably 1:1 - 3:2.

[0012] When the penetration enhancer is a combination of 1,2 - propylene glycol and crotamiton, the mass ratio of 1,2 - propylene glycol to crotamiton is 1:3 - 5 or 8 - 10:1.

[0013] The stabilizer is one or a combination of two of HPMC E5 and HPMC E50.

[0014] The dosage of the stabilizer is 0.01 - 0.02%.

[0015] The preservative is a combination of sodium benzoate and potassium sorbate.

[0016] The humectant is sodium hyaluronate.

[0017] Furthermore, the present invention preferably provides the following pyriproxyfen methoprene thermosensitive gel, wherein the weight - volume percentage of each component in the thermosensitive gel is: pyriproxyfen 10%, methoprene 12%, poloxamer 407 13 - 14%, HPMC E5 0 - 0.02%, HPMC E50 0 - 0.02%, 1,2 - propylene glycol 3.0 - 5.0%, laurocapram 0 - 2.0%, absolute ethanol 28.0 - 30.0%, the combination of sodium benzoate and potassium sorbate 0.05 - 0.1%, sodium hyaluronate 0.05 - 0.1%, and the balance is water.

[0018] Furthermore, the mass ratio of poloxamer 407 to the penetration enhancer is 1.8 - 5:1.

[0019] The preparation process of the thermosensitive gel of the present invention is as follows:

[0020] (1) Shake poloxamer 407 and the stabilizer and add them to distilled water to obtain an aqueous solution of poloxamer 407;

[0021] (2) Add sodium hyaluronate, the preservative, and the penetration enhancer to the aqueous solution of poloxamer 407, stir evenly, seal, and let stand to obtain a matrix solution;

[0022] (3) Add absolute ethanol, pyriproxyfen, and methoprene to the above - mentioned matrix solution, stir evenly, dissolve by ultrasonic treatment, seal, and let stand.

[0023] (4) Make up the volume to a certain volume with distilled water, stir evenly, and divide into portions with a volume of 0.5 mL to obtain the product.

[0024] Each portion of the prepared thermosensitive gel contains 50 mg of fipronil and 60 mg of methoprene, which is consistent with the drug content of the commercially available product. This preparation is usually stored sealed at room temperature.

[0025] In this experiment, the gelation temperature and the transdermal experiment on rats were used as research methods, and the gelation temperature, gelation time, and transdermal duration were used as evaluation indexes to obtain the optimal thermosensitive gel.

[0026] The results showed that: the gelation temperature of the thermosensitive gel prepared by the present invention was 32±1°C, and the cumulative drug permeation amount of the prepared gel was more than 20% of the cumulative drug permeation amount of the commercially available product. The fitting transdermal duration of one or both of methoprene or fipronil was longer than that of the corresponding drug in the commercially available "Frontline". Among them, when 1,2-propanediol and cromolyn were used as penetration enhancers, the cumulative permeation amounts of the two drugs could reach about 30% of the commercially available product, and the fitting transdermal durations could be more than 2.5 times that of the commercially available product. Description of the Drawings

[0027] Figure 1 It is the gelation temperature diagram of Examples 1-39.

[0028] Figure 2 It is the gelation time diagram of Examples 1-39.

[0029] Figure 3 It is the diagram of the cumulative permeation amount of fipronil over time for Frontline, Examples 8, 11, 14, 15, 32, 33, 36, 37, 38, 39.

[0030] A: Diagram of the cumulative permeation amount of fipronil over time for Frontline, Examples 8, 14, 15, 32, 33.

[0031] B: Diagram of the cumulative permeation amount of fipronil over time for Examples 11, 36-39.

[0032] Figure 4 It is the diagram of the cumulative permeation amount of methoprene over time for Frontline, Examples 8, 11, 14, 15, 32, 33, 36, 37, 38, 39.

[0033] A: Diagram of the cumulative permeation amount of methoprene over time for Frontline, Examples 8, 14, 15, 32, 33.

[0034] B: Diagram of the cumulative permeation amount of methoprene over time for Examples 11, 36-39. Detailed Description of the Invention

[0035] Examples 1-39

[0036] The formulations of Examples 1-39 are shown in Table 1.

[0037] Prepare the thermosensitive gels of Examples 1-39 according to the following preparation method:

[0038] (1) Mix poloxamer 407 and HPMC evenly and add them to 12.0 mL of distilled water. Place it in a refrigerator at 4 °C overnight to obtain an aqueous solution of poloxamer 407.

[0039] (2) Add the combination of potassium sorbate and sodium benzoate as preservatives, a penetration enhancer, and sodium hyaluronate to the aqueous solution of poloxamer 407. Stir evenly, seal, and let it stand in a refrigerator at 4 °C for 1 hour to obtain a matrix solution.

[0040] (3) Add anhydrous ethanol (15.0 mL in amount), pyriproxyfen, and methoprene to the matrix solution prepared in step (2). Ultrasonic in an ultrasonic instrument at room temperature for 30 min until the drug is completely dissolved. After taking it out, make up to 50.0 mL with distilled water, stir evenly, and divide into portions (specification: 0.5 mL, each 0.5 mL contains 50 mg of pyriproxyfen and 60 mg of methoprene) to obtain a thermosensitive gel. Seal and store at room temperature. The obtained preparation is in a milky white and slightly viscous state.

[0041] Determination of the gelation temperature of the thermosensitive gel: Take 0.5 mL of the gel of the example at room temperature into a glass test tube. At this time, the preparation is in a sol state. Place the glass test tube in a water bath and observe the temperature at which the sol turns into a gel under different temperature conditions, which is the gelation temperature. Each example is measured three times and the average value is calculated.

[0042] Determination of the gelation time: Use a constant temperature water bath to heat, and then invert to observe whether it gels. The longer the gelation time, the smaller the viscosity of the system.

[0043] Table 1 Formulation table of Examples 1 - 39

[0044]

[0045]

[0046] In Examples 1 - 7, 1,2 - propanediol was used as a penetration enhancer. The amount of 1,2 - propanediol was fixed. Under the condition that other components were the same, the amount of poloxamer 407 was changed, which was equivalent to changing the concentration of poloxamer 407. When the mass - volume percentage content of poloxamer 407 was 8 - 18%, the gelation temperature of the preparation was different. Therefore, the concentration of poloxamer directly affected the gelation temperature of the gel, and the gelation temperature decreased with the increase of the concentration of poloxamer 407. When the concentration of poloxamer 407 was 13 - 14%, the gelation temperature of the preparation was between 32 ± 1 °C.

[0047] Furthermore, the concentration of poloxamer 407 was determined to be 13.6%. When the other components were the same, the type and amount of the penetration enhancer were changed, 1,2-propylene glycol was used as the penetration enhancer, or a combination of 1,2-propylene glycol and laurocapram was used as the penetration enhancer, and the effects of different penetration enhancer compositions and amounts on the gelation temperature and gelation time of the gel were investigated. The formulations are shown in Examples 8-13.

[0048] The results of Examples 8 and 10 show that, when other components are the same, 1,2-propylene glycol is used as a penetration enhancer, and the concentration of 1,2-propylene glycol is changed, the gelling temperature of the preparation is different, and the fluidity of the preparation at room temperature increases. When the concentration of 1,2-propylene glycol is 5-7%, the gelling temperature of the prepared gel is 32±1°C, so the concentration of 1,2-propylene glycol is selected to be 5-7%.

[0049] The results of Examples 9, 11, 12 and 13 show that when the combination of 1,2-propylene glycol and lauryl azone is used as a penetration enhancer, the gelling temperature of the preparation is different when the ratio between the two is changed. When the mass ratio of 1,2-propylene glycol to lauryl azone is 3:2-2:3, the gelling temperature of the gel is 32±1°C. When the combination of 1,2-propylene glycol and lauryl azone is selected to be less than that of 1,2-propylene glycol alone, the fluidity of the preparation at room temperature is reduced, but there is no greater effect on the form of the preparation. Therefore, the penetration enhancer of the present invention is preferably 5-7% of 1,2-propylene glycol and a combination of 1,2-propylene glycol and lauryl azone in a mass ratio of 3:2-2:3.

[0050] Furthermore, the dosage of poloxamer and 1,2-propylene glycol was determined, and the effects of adding different types and dosages of HPMC on the gelation temperature and gelation time of the gel were investigated. The specific formulations are shown in Examples 14-20.

[0051] The results show that, when other components are the same, adding HPMC E5 or HPMC E50 or the combination of the two increases the fluidity of the preparation at room temperature and the gelation temperature. In particular, when the two are used together, the fluidity of the preparation at room temperature increases significantly and the gelation temperature increases significantly. When HPMC E5 or HPMC E50 is used alone at a concentration of 0.01-0.02%, the gelation temperature of the gel is 32±1°C.

[0052] Next, fix the concentration of HPMC E50 at 0.02%, use the combination of 1,2 - propylene glycol and laurocapram as the penetration enhancer, with the concentration of the penetration enhancer being 5%. Change the ratio between the two, and investigate the effects of different ratios of 1,2 - propylene glycol and laurocapram on the gelation temperature and gelation time of the gel. The formulation and results are shown in Examples 21 - 27. The results indicate that as the concentration of laurocapram increases, the fluidity of the preparation at room temperature gradually decreases, and the gelation temperature gradually decreases. When the mass ratio of 1,2 - propylene glycol to laurocapram is 4:1 - 2:3, the gelation temperature is 32 ± 1 °C.

[0053] Based on Example 15, change the ratio of poloxamer 407 to 1,2 - propylene glycol (the ratio is 10:1 - 4:1). The results of Examples 28 - 31 show that as the concentration of 1,2 - propylene glycol increases, the fluidity of the preparation at room temperature gradually increases. When the ratio of poloxamer 407 to 1,2 - propylene glycol is 4:1 - 5:1, the gelation temperature is 32 ± 1 °C.

[0054] In order to investigate the effects of the penetration enhancer on the gelation temperature and gelation time of the gel after adding HPMC. When the dosage of poloxamer 407 and the total amount of the penetration enhancer are fixed, change the penetration enhancer to the combination of 1,2 - propylene glycol and crotamiton. The results show that when the mass ratio of 1,2 - propylene glycol to crotamiton is 1:4 or 9:1, the gelation temperature of the gel is 32 ± 1 °C. The addition of crotamiton does not affect the fluidity of the preparation at room temperature, and there is not much change in the gelation temperature either.

[0055] Experimental Example 1 Transdermal Test of Thermosensitive Gel

[0056] Transdermal Test on Rats

[0057] The commercially available "Frontline" drops are administered once a month. The effective components of the compound fipronil methoprene thermosensitive gel are fipronil and methoprene. Fipronil acts as an adulticide on adult ticks and fleas, and methoprene acts as an insect growth regulator on flea eggs and larvae. Therefore, the present invention can effectively prevent and treat animal flea and tick infections, and can be used as an adjuvant treatment for flea - induced allergic dermatitis. The insecticidal effect is stable and has high application value.

[0058] In this experiment, a vertical diffusion cell is used. The rat skin is fixed between the dosing chamber and the receiving chamber, with the stratum corneum facing the supply chamber and the dermis facing the receiving chamber. The effective diffusion area is 1.54 cm 2The embodiments 8, 11, 14, 15, 32, 33, 36, 37, 38, 39 and the commercially available "Frontline" drops were respectively added to the dosing pool and evenly applied on the skin of rats. Additionally, 4 ml of 30% ethanol physiological saline was added to the receiving pool. After removing air bubbles, the skin of the rats was made to contact the liquid surface. Under the conditions of 32 °C and 500 (r / min), continuous stirring was carried out. At 0.5 h, 1 h, 3 h, 5 h, 7 h, 18 h, 20 h, 22 h, 24 h, 28 h, 32 h, 44 h, and 48 h after administration, 4 ml of the receiving liquid was extracted and fresh receiving liquid of the same volume and temperature was replenished. The extracted receiving liquid was filtered through a 0.45 μm filter membrane to obtain the filtrate, and the ultraviolet absorbance was measured to calculate the cumulative permeation amount Q. The results are shown in Table 2.

[0059]

[0060] ρn is the mass concentration at the nth sampling point (μg·mL －1 ), V is the sampling volume, and A is the permeation area.

[0061] Table 2 Cumulative transdermal amount and transdermal duration of the drug

[0062]

[0063] After a 48-hour transdermal test on rats, the results showed that:

[0064] The cumulative transdermal permeation amount of methoprene in the commercially available product Frontline was 0.1157 mg / cm 2 , the drug release time was 24388 h, and the cumulative transdermal permeation amount of fipronil was 0.1068 mg / cm 2 , and the drug release time was 18178 h.

[0065] For the 3 batches of test samples of Example 8, the cumulative transdermal permeation amount of methoprene was 0.0618 mg / cm 2 , the sustained release time was 32255 h; the cumulative transdermal permeation amount of fipronil was 0.0719 mg / cm 2 , and the sustained release time was 27034 h.

[0066] The above results indicate that the permeation durations of methoprene and fipronil in Example 8 were 1.3 times and 1.5 times that of Frontline, respectively.

[0067] The cumulative transdermal permeation amount of methoprene in Example 14 was 0.0462 mg / cm 2 , the release duration was 49987 h, which was 2.0 times that of Frontline; the cumulative transdermal permeation amount of fipronil was 0.0524 mg / cm 2 , and the release duration was 24388 h, which was 1.3 times that of the commercially available product.

[0068] The cumulative transdermal penetration amount of methoprene in Example 15 was 0.0593 mg / cm 2 , and the release duration was 39985 h, which was 1.6 times that of Frontline; the cumulative transdermal penetration amount of fipronil was 0.0865 mg / cm 2 , and the release duration was 24384 h, which was 1.3 times that of Frontline.

[0069] The above results show that, compared with Example 8 without HPMC, HPMC E5 has no promoting effect on drug penetration and slows down drug penetration. HPMC E50 has a promoting effect on the penetration of fipronil, has no obvious effect on the penetration of methoprene, and has a longer sustained release time than Frontline.

[0070] The cumulative transdermal penetration amount of methoprene in Example 32 was 0.0934 mg / cm 2 , and the release duration was 20537 h, which was 0.8 times that of Frontline; the cumulative transdermal penetration amount of fipronil was 0.0449 mg / cm 2 , and the release duration was 38456 h, which was 2.1 times that of Frontline.

[0071] The cumulative transdermal penetration amount of methoprene in Example 33 was 0.0331 mg / cm 2 , and the release duration was 59994 h, which was 2.5 times that of Frontline; the cumulative transdermal penetration amount of fipronil was 0.03175 mg / cm 2 , and the release duration was 49994 h, which was 2.8 times that of Frontline. The thermosensitive gel prepared by Example 33 can achieve a good sustained release effect, and the expected sustained release duration is at least more than 2 months.

[0072] The transdermal results of Examples 36 - 39 show that Example 36 (crotamiton is 0.5%, and both HPMC E5 and E50 are 0.01%) has the best permeation promoting effect. The transdermal duration of fipronil was 21735 h, which was 2.0 times that of Frontline, and the transdermal duration of methoprene was 7054 h, which was 0.3 times that of Frontline. In addition, crotamiton has a particularly significant promoting effect on the permeation of methoprene, and the transdermal duration is greatly reduced.

Claims

1. A non-prednisolone methoprene thermosensitive gel, characterized in that: The thermosensitive gel comprises fepronil, methoprene, poloxamer 407, a stabilizer, a penetration enhancer, a preservative, anhydrous ethanol, a moisturizer and distilled water; the weight volume percentage of each component in the thermosensitive gel is: 10% of fepronil, 12% of methoprene, 12-14% of poloxamer 407, 0-0.05% of the stabilizer, 2.5-7.0% of the penetration enhancer, 28.0-30.0% of the anhydrous ethanol, 0.05-0.1% of the preservative, 0.05-0.1% of the moisturizer and the balance of water.

2. The non-prednisolone methoprene thermosensitive gel according to claim 1, characterized in that The penetration enhancer is one or a combination of 1,2-propylene glycol, laurocapram and crotamiton; preferably 1,2-propylene glycol, a combination of 1,2-propylene glycol and laurocapram, and a combination of 1,2-propylene glycol and crotamiton.

3. The non-prednisolone methoprene thermosensitive gel according to claim 2, characterized in that: When the penetration enhancer is a combination of 1,2-propylene glycol and lauryl azone, the mass ratio of 1,2-propylene glycol to lauryl azone is 2:3-4:1, preferably 1:1-3:

2.

4. The non-prednisolone methoprene thermosensitive gel according to claim 2, characterized in that: When the penetration enhancer is a combination of 1,2-propylene glycol and crotamiton, the mass ratio of 1,2-propylene glycol to crotamiton is 1:3-5 or 8-10:

1.

5. The non-prednisolone methoprene thermosensitive gel according to claim 1, characterized in that: The stabilizer is one or a combination of HPMC E50 and HPMC E50, and the dosage is 0.01-0.02%.

6. The fepronil methoxyprene thermosensitive gel according to any one of claims 1 to 5, characterized in that: Fipronil 10%, methoprene 12%, poloxamer 407 13-14%, HPMC E5 0-0.02%, HPMC E50 0-0.02%, 1,2-propylene glycol 3.0-5.0%, laurocapram 0-2.0%, anhydrous ethanol 28.0-30.0%, a combination of sodium benzoate and potassium sorbate 0.05-0.1%, sodium hyaluronate 0.05-0.1%, and the balance is water; Or the weight volume percentage of each component in the thermosensitive gel is: 10% of fepronil, 12% of methoprene, 13-14% of poloxamer 407, 0-0.02% of HPMC E5, 0-0.02% of HPMC E50, 3.0-5.0% of 1,2-propylene glycol, 0.5-4.0% of crotamiton, 28.0-30.0% of anhydrous ethanol, 0.05-0.1% of a combination of sodium benzoate and potassium sorbate, 0.05-0.1% of sodium hyaluronate, and the balance of water.

7. The fepronil methoprene thermosensitive gel according to any one of claims 1 to 6, characterized in that: The weight volume percentage of each component in the thermosensitive gel is: 10% of fepronil, 12% of methoprene, 13-14% of poloxamer 407, 4.0-5.0% of 1,2-propylene glycol, 28.0-30.0% of anhydrous ethanol, 0.05-0.1% of a combination of sodium benzoate and potassium sorbate, 0.05-0.1% of sodium hyaluronate, and the balance of water.

8. The fepronil methoprene thermosensitive gel according to any one of claims 1 to 7, characterized in that: The mass ratio of poloxamer 407 to the penetration enhancer is 1.8-5:

1.

9. The method for preparing the fepronil methoprene thermosensitive gel according to claim 1, characterized in that: (1) Poloxamer 407 and a stabilizer are shaken and then added into distilled water to obtain an aqueous solution of poloxamer 407; (2) adding sodium hyaluronate, preservatives, and penetration enhancers to the aqueous solution of poloxamer 407, stirring evenly, sealing, and standing to obtain a matrix solution; (3) adding anhydrous ethanol, fipronil and methoprene to the above matrix solution, stirring evenly, dissolving by ultrasonication, sealing and allowing to stand; (4) Add distilled water to a certain volume, stir evenly, and divide into 0.5 mL portions.

10. Use of the fepronil methoprene thermosensitive gel according to any one of claims 1 to 8 in the preparation of insecticides.

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