Chlortetracycline hydrochloride inclusion compound, preparation method and application thereof, chlortetracycline hydrochloride injection preparation and application thereof

Abstract

The invention relates to the technical field of injection preparations, in particular to a chlortetracycline hydrochloride inclusion compound, a preparation method and application thereof, a chlortetracycline hydrochloride injection preparation and application thereof. The chlortetracycline hydrochloride inclusion compound is mainly prepared from chlortetracycline hydrochloride and a coating material or prepared from chlortetracycline hydrochloride, the coating material and a hydrophilic polymer, the solubility and stability of chlortetracycline hydrochloride can be improved by using the coating material, and the stability constant of the inclusion compound is larger and the inclusion rate is higher by using the hydrophilic polymer; the problems of solubility and stability of chlortetracycline hydrochloride are obviously improved. The chlortetracycline hydrochloride clathrate compound, water, N, N-dimethylformamide and polyethylene glycol 600 are mixed and then filtered, the chlortetracycline hydrochloride injection preparation is prepared in a low-cost and high-safety mode, and the injection preparation has good antibacterial performance.

Description

Technical Field

[0001] The present invention relates to the technical field of injection preparations, and particularly relates to a chlortetracycline hydrochloride inclusion compound, a preparation method and application thereof, a chlortetracycline hydrochloride injection preparation and an application thereof. Background Art

[0002] The chemical name of chlortetracycline hydrochloride is 6-methyl-4-(dimethylamino)-3,6,10,12,12α-pentahydroxy-1,1-dioxo-7-chloro-1,4,4α,5,5α,6,11,12α-octahydro-2-naphthacenecarboxamide hydrochloride. It is a tetracycline antibiotic first discovered by Dr. Benjamin in Streptomyces aureofaciens in 1945 and is composed of actinomycetes. It has the advantages of a broad antibacterial spectrum, a short withdrawal period, and low price. Chlortetracycline hydrochloride acts by inhibiting the protein synthesis of sensitive microorganisms, so it has broad antibacterial activity against both Gram-positive bacteria and Gram-negative bacteria, and can effectively prevent and treat bacterial enteritis, pneumonia, swine dysentery, etc. The US Food and Drug Administration (FDA) has approved chlortetracycline hydrochloride for use in chickens, pigs, calves, etc., so it is widely used to treat animal diseases and human infectious diseases.

[0003] At present, the commonly used chlortetracycline hydrochloride preparations in clinics have a single dosage form, mostly soluble powders, and their bioavailability is low. Moreover, chlortetracycline hydrochloride has unstable chemical properties and strong hydrophobicity, and is easily degraded and inactivated in acidic solutions (pH < 2), neutral solutions or alkaline solutions (pH > 7). Summary of the Invention

[0004] The purpose of the present invention is to provide a chlortetracycline hydrochloride injection preparation and a preparation method thereof, so as to improve the solubility and stability of chlortetracycline hydrochloride.

[0005] In order to achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:

[0006] A chlortetracycline hydrochloride inclusion compound, the raw materials of which include chlortetracycline hydrochloride and a coating material;

[0007] The molar ratio of the chlortetracycline hydrochloride to the coating material is 1:0.25 - 2;

[0008] The coating material includes at least one of β-cyclodextrin, hydroxypropyl-β-cyclodextrin, sulfobutyl-β-cyclodextrin and PLGA.

[0009] Optionally, the raw materials of the chlortetracycline hydrochloride inclusion compound further include a hydrophilic polymer; the hydrophilic polymer includes polyvinyl alcohol, polyvinylpyrrolidone K30, ethyl cellulose, Apisolex TM, At least one of HS15 and Crodasol TMHS HP; the molar ratio of chlortetracycline hydrochloride to the hydrophilic polymer is 1:0.05 to 1.

[0010] The present invention provides a preparation method of a chlortetracycline hydrochloride inclusion complex, comprising the following steps:

[0011] Mix chlortetracycline hydrochloride, an organic solvent and an aqueous solution of a coating material, and sequentially carry out heating, freezing and drying to obtain the chlortetracycline hydrochloride inclusion complex.

[0012] Optionally, in the preparation method of the chlortetracycline hydrochloride inclusion complex, the organic solvent comprises at least one of ethanol, methanol and acetonitrile, and the dosage ratio of chlortetracycline hydrochloride to the organic solvent is 1 g:100 to 300 mL.

[0013] Optionally, in the preparation method of the chlortetracycline hydrochloride inclusion complex, when the raw materials include a hydrophilic polymer, the preparation method of the chlortetracycline hydrochloride inclusion complex comprises the following steps: mix chlortetracycline hydrochloride and the hydrophilic polymer and then carry out ball milling to obtain a solid dispersion;

[0014] Mix the solid dispersion with water to obtain a drug solution;

[0015] Mix the drug solution with an aqueous solution of a coating material, and sequentially carry out freezing and drying to obtain the chlortetracycline hydrochloride inclusion complex.

[0016] The present invention provides the application of the chlortetracycline hydrochloride inclusion complex in the preparation of a chlortetracycline hydrochloride injection preparation.

[0017] The present invention also provides a chlortetracycline hydrochloride injection preparation, which, by volume, comprises 25 to 50 parts of a cosolvent; 60 to 70 parts of water; the volume concentration of chlortetracycline hydrochloride in the chlortetracycline hydrochloride injection preparation is 1.5 to 8%.

[0018] Optionally, the cosolvent comprises at least one of N,N-dimethylformamide, polyethylene glycol, Tween 80, sodium carboxymethylcellulose and 1,2-propanediol; the pH of the chlortetracycline hydrochloride injection preparation is 4 to 5.

[0019] Optionally, when the raw materials of the chlortetracycline hydrochloride inclusion complex do not contain a hydrophilic polymer, the volume concentration of chlortetracycline hydrochloride in the chlortetracycline hydrochloride injection preparation is 1.5 to 3%; when the raw materials of the chlortetracycline hydrochloride inclusion complex contain a hydrophilic polymer, the volume concentration of chlortetracycline hydrochloride in the chlortetracycline hydrochloride injection preparation is 3 to 8%.

[0020] The present invention also provides the application of the chlortetracycline hydrochloride injection preparation in antibacterial aspects.

[0021] The beneficial effects of the present invention:

[0022] The present invention provides a chlortetracycline hydrochloride inclusion complex, which has good solubility and stability. During the preparation process of the chlortetracycline hydrochloride inclusion complex, the raw materials thereof include a coating material. The central cavity of the coating material with poor hydrophobicity combines with the lipophilic part of the drug molecule to produce an effect. When the drug molecule enters the central cavity of the coating material, a conformational adjustment will occur, maximizing the use of van der Waals forces to increase the solubility and stability of chlortetracycline hydrochloride. In addition, a hydrophilic polymer can also be used to prepare the chlortetracycline hydrochloride inclusion complex. The use of the hydrophilic polymer can further improve the stability constant and inclusion rate of the inclusion complex, further enhance the solubility and stability of chlortetracycline hydrochloride, and can be used for the preparation of chlortetracycline hydrochloride injection preparations.

[0023] The preparation process of the chlortetracycline hydrochloride injection preparation prepared using the chlortetracycline hydrochloride inclusion complex is simple, does not require special production equipment, has low costs, high safety, is suitable for large-scale industrial production, and has good antibacterial properties. Compared with the oral chlortetracycline premix, the injection can directly enter the blood circulation to exert its effect. Description of the Drawings

[0024] Figure 1 It is a microscopic picture of a pathological section of animal tissues of the model group, drug control group A, and drug control group B collected in Application Example 3. Detailed Embodiments

[0025] The present invention provides a chlortetracycline hydrochloride inclusion complex, and its raw materials include chlortetracycline hydrochloride and a coating material;

[0026] The molar ratio of the chlortetracycline hydrochloride to the coating material is 1:0.25 - 2;

[0027] The coating material includes at least one of β-cyclodextrin, hydroxypropyl-β-cyclodextrin, sulfobutyl-β-cyclodextrin, and PLGA.

[0028] Preferably, the raw materials of the chlortetracycline hydrochloride inclusion complex of the present invention further include a hydrophilic polymer; the hydrophilic polymer preferably includes at least one of polyvinyl alcohol, polyvinylpyrrolidone K30, ethyl cellulose, Apisolex TM, HS15, and Crodasol TM HS HP; the molar ratio of the chlortetracycline hydrochloride to the hydrophilic polymer is preferably 1:0.05 - 1.

[0029] The present invention provides a method for preparing a chlortetracycline hydrochloride inclusion complex, which includes the following steps:

[0030] Mix chlortetracycline hydrochloride, an organic solvent, and an aqueous solution of the coating material, and sequentially perform heating, freezing, and drying to obtain a solid powder of the chlortetracycline hydrochloride inclusion complex.

[0031] In the preparation method of the chlortetracycline hydrochloride clathrate of the present invention, the organic solvent preferably includes at least one of ethanol, methanol and acetonitrile, and the dosage ratio of chlortetracycline hydrochloride to the organic solvent is preferably 1 g: 100 - 300 mL, more preferably 1 g: 150 - 200 mL; the organic solvent can promote the dissolution of chlortetracycline hydrochloride.

[0032] In the preparation method of the chlortetracycline hydrochloride clathrate of the present invention, the temperature of heating is preferably 60 °C, the pressure is preferably -80 mpa, and the time is preferably 10 min. Heating is to remove the organic solvent; the temperature of freezing is preferably -80 °C, and the time is preferably 24 h; the drying method is preferably freeze-drying, the temperature is preferably -80 °C, and the time is preferably 24 h.

[0033] In the preparation method of the chlortetracycline hydrochloride clathrate of the present invention, when the raw material contains a hydrophilic polymer, the preparation method of the chlortetracycline hydrochloride clathrate preferably includes the following steps: mixing chlortetracycline hydrochloride and the hydrophilic polymer and then ball-milling to obtain a solid dispersion;

[0034] Mixing the solid dispersion with water to obtain a drug solution;

[0035] Mixing the drug solution with an aqueous solution of the coating material, and sequentially performing freezing and drying to obtain the chlortetracycline hydrochloride clathrate.

[0036] In the preparation method of the chlortetracycline hydrochloride clathrate of the present invention, when the raw material contains a hydrophilic polymer, the ball-milling in the preparation method preferably means placing chlortetracycline hydrochloride and the hydrophilic polymer in a grinding tank, putting 16 grinding beads of different sizes (diameter 2 - 15 mm), and grinding in a media mill at 350 rpm for 1 h. After ball-milling, it is preferably sieved to obtain a solid dispersion; the temperature of freezing is preferably -20 °C, and the time is preferably 12 h; the drying method is preferably freeze-drying, the temperature is preferably -80 °C, and the time is preferably 24 h.

[0037] The present invention provides the application of the chlortetracycline hydrochloride clathrate in the preparation of a chlortetracycline injection preparation.

[0038] The present invention also provides a chlortetracycline injection preparation, which contains 25 - 50 parts of a cosolvent; 60 - 70 parts of water by volume; the volume concentration of chlortetracycline hydrochloride in the chlortetracycline injection preparation is 1.5 - 8%.

[0039] In the present invention, the volume fraction of the cosolvent is preferably 30 to 45 parts; the cosolvent preferably comprises at least one of N,N-dimethylformamide, polyethylene glycol, Tween 80, sodium carboxymethyl cellulose, and 1,2-propanediol; when there are two or more of the above cosolvents, the ratio between the cosolvents can be determined according to the actual situation. Preferably, when the cosolvents are N,N-dimethylformamide and polyethylene glycol 600, their volume ratio is 15:10.

[0040] The pH of the chlortetracycline hydrochloride injection preparation is preferably 4 to 5, and more preferably 4.15 to 4.5; a pH value of 4 to 5 is the optimal stability range of the chlortetracycline hydrochloride injection, and adjusting the pH can reduce the irritation of the injection.

[0041] In the present invention, the preparation method of the chlortetracycline hydrochloride injection preparation preferably comprises dissolving the chlortetracycline hydrochloride inclusion complex in water, then adding the cosolvent and mixing well. After the drug is completely dissolved, the pH value is adjusted using PBS buffer solution, and the chlortetracycline hydrochloride injection preparation is obtained through filtration; the polyethylene glycol is preferably polyethylene glycol 600.

[0042] In the chlortetracycline hydrochloride injection preparation of the present invention, the volume concentration of chlortetracycline hydrochloride in the chlortetracycline hydrochloride injection preparation is preferably 1.5 to 8%.

[0043] In the chlortetracycline hydrochloride injection preparation of the present invention, when the raw material of the chlortetracycline hydrochloride inclusion complex does not contain a hydrophilic polymer, the volume concentration of chlortetracycline hydrochloride in the chlortetracycline hydrochloride injection preparation is preferably 1.5 to 3%; when the raw material of the chlortetracycline hydrochloride inclusion complex contains a hydrophilic polymer, the volume concentration of chlortetracycline hydrochloride in the chlortetracycline hydrochloride injection preparation is preferably 3 to 8%.

[0044] In the chlortetracycline hydrochloride injection preparation of the present invention, preferably, when the coating material is β-cyclodextrin or sulfobutyl-β-cyclodextrin, the volume concentration of chlortetracycline hydrochloride in the obtained chlortetracycline hydrochloride injection preparation is 1.5%;

[0045] When the coating material is hydroxypropyl-β-cyclodextrin or PLGA, the volume concentration of chlortetracycline hydrochloride in the obtained chlortetracycline hydrochloride injection preparation is 1.5 to 3%;

[0046] When the hydrophilic polymer is polyvinylpyrrolidone K30 or Apisolex TM and the coating material is hydroxypropyl-β-cyclodextrin or PLGA, the volume concentration of chlortetracycline hydrochloride in the obtained chlortetracycline hydrochloride injection preparation is 3 to 5%.

[0047] The present invention also provides the application of the chlortetracycline hydrochloride injection preparation in antibacterial.

[0048] The technical solution provided by the present invention will be described in detail below in conjunction with embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0049] Example 1

[0050] Dissolve 1.5 g of chlortetracycline hydrochloride in 150 mL of ethanol to obtain a chlortetracycline hydrochloride solution;

[0051] Dissolve 2 g of β-cyclodextrin in 50 mL of distilled water to obtain an aqueous solution of the coating material;

[0052] Mix the obtained chlortetracycline hydrochloride solution with the aqueous solution of the coating material, and stir magnetically at a speed of 800 rpm for 4 h to fully mix. Then place it in a rotary evaporator and evaporate for 10 min at 60 °C and a pressure of -80 mPa to remove the organic solvent. After the evaporation of the organic solvent is completed, place the solution in a refrigerator at -80 °C and freeze for 24 h. When the solution is completely frozen, place it in a freeze dryer at -80 °C for 24 h to complete vacuum drying. Finally, obtain the solid powder of chlortetracycline hydrochloride clathrate after grinding, pulverizing and sieving;

[0053] Add all the prepared solid powder of chlortetracycline hydrochloride clathrate to 70 mL of water for injection; then add 15 mL of N,N-dimethylformamide and 10 mL of polyethylene glycol 600 and stir evenly; adjust the pH to 4.15 with PBS buffer solution to obtain an injection of chlortetracycline hydrochloride clathrate, and obtain an injection preparation of chlortetracycline hydrochloride after filtering with a 0.22 μm PVDF filter element; the volume concentration of chlortetracycline hydrochloride in the injection preparation is 1.5%.

[0054] Example 2

[0055] Based on Example 1, the difference between Example 2 and Example 1 is that hydroxypropyl-β-cyclodextrin is used instead of β-cyclodextrin; the volume concentration of chlortetracycline hydrochloride in the injection preparation is 1.5%.

[0056] Example 3

[0057] Based on Example 1, the difference between Example 3 and Example 1 is that sulfobutyl-β-cyclodextrin is used instead of β-cyclodextrin; the volume concentration of chlortetracycline hydrochloride in the injection preparation is 1.5%.

[0058] Example 4

[0059] Based on Example 1, the difference between Example 4 and Example 1 is that PLGA is used instead of β-cyclodextrin; the volume concentration of chlortetracycline hydrochloride in the injection preparation is 1.5%.

[0060] Example 5

[0061] Dissolve 3 g of chlortetracycline hydrochloride in 300 mL of ethanol to obtain a chlortetracycline hydrochloride solution;

[0062] Dissolve 10 g of hydroxypropyl-β-cyclodextrin in 50 mL of distilled water to obtain an aqueous solution of the coating material;

[0063] Mix the obtained chlortetracycline hydrochloride solution with the aqueous solution of the coating material, and magnetically stir at a speed of 800 rpm for 4 h to fully mix. Then place it in a rotary evaporator and evaporate for 10 min at 60 °C and a pressure of -80 mPa to remove the organic solvent. After the evaporation of the organic solvent is completed, place the solution in a refrigerator at -80 °C and freeze for 24 h. When the solution is completely frozen, place it in a freeze dryer at -80 °C for 24 h to complete vacuum drying. Finally, obtain the solid powder of chlortetracycline hydrochloride inclusion complex after grinding, pulverizing and sieving;

[0064] Add all the obtained solid powder of chlortetracycline hydrochloride inclusion complex to 70 mL of water for injection; then add 15 mL of N,N-dimethylformamide and 10 mL of polyethylene glycol 600 and stir evenly; adjust the pH to 4.15 with PBS buffer solution to obtain an injection of chlortetracycline hydrochloride inclusion complex, and obtain an injection preparation of chlortetracycline hydrochloride after filtering with a 0.22 μm PVDF filter element; the volume concentration of chlortetracycline hydrochloride in the injection preparation is 3%.

[0065] Example 6

[0066] Based on Example 5, the difference between Example 6 and Example 5 is that PLGA is used instead of hydroxypropyl-β-cyclodextrin; the volume concentration of chlortetracycline hydrochloride in the injection preparation is 3%.

[0067] Example 7

[0068] Place 3 g of chlortetracycline hydrochloride and 2 g of polyvinylpyrrolidone K30 in a grinding jar, put in 16 grinding beads of different sizes (diameter 2 - 15 mm), and grind in a media mill at a speed of 350 rpm for 1 h. Obtain a solid dispersion after sieving, and weigh 5 g of the solid dispersion and dissolve it in 150 mL of distilled water to obtain a drug solution;

[0069] Dissolve 8 g of hydroxypropyl-β-cyclodextrin in 50 mL of distilled water to obtain an aqueous solution of the coating material;

[0070] Mix the obtained drug solution with the aqueous solution of the coating material, and magnetically stir at a speed of 800 rpm for 4 h to fully mix. Then place the solution in a refrigerator at -80 °C and freeze for 24 h. When the solution is completely frozen, place it in a freeze dryer at -80 °C to complete vacuum drying. Finally, obtain the chlortetracycline hydrochloride inclusion complex after grinding, pulverizing and sieving;

[0071] All of the prepared chlortetracycline hydrochloride inclusion complex was added to 60 mL of water for injection; then 15 mL of N,N-dimethylformamide and 10 mL of polyethylene glycol 600 were added and stirred evenly; the pH was adjusted to 4.15 with PBS buffer solution to obtain a chlortetracycline hydrochloride inclusion complex injection solution, and a chlortetracycline hydrochloride injection preparation was obtained after filtration with a 0.22 μm PVDF filter element; the volume concentration of chlortetracycline hydrochloride in the injection preparation was 3%.

[0072] Example 8

[0073] Based on Example 7, the difference between Example 8 and Example 7 is that PLGA is used instead of hydroxypropyl-β-cyclodextrin; the volume concentration of chlortetracycline hydrochloride in the injection preparation is 3%.

[0074] Example 9

[0075] Based on Example 7, the difference between Example 9 and Example 7 is that Apisolex TM is used instead of povidone K30; the volume concentration of chlortetracycline hydrochloride in the injection preparation is 3%.

[0076] Example 10

[0077] Based on Example 7, the difference between Example 10 and Example 7 is that Apisolex TM is used instead of povidone K30 and PLGA is used instead of hydroxypropyl-β-cyclodextrin; the volume concentration of chlortetracycline hydrochloride in the injection preparation is 3%.

[0078] Example 11

[0079] 5 g of chlortetracycline hydrochloride and 5 g of povidone K30 were placed in a grinding jar, 16 grinding beads of different sizes (diameter 2 - 15 mm) were put in, and ground in a media mill at a speed of 350 rpm for 1 h. After sieving, a solid dispersion was obtained. 10 g of the solid dispersion was weighed and dissolved in 300 mL of water to obtain a drug solution;

[0080] 10 g of hydroxypropyl-β-cyclodextrin was dissolved in 50 mL of distilled water to obtain an aqueous solution of the coating material;

[0081] The obtained drug solution and the aqueous solution of the coating material were mixed and stirred evenly with magnetic stirring at a speed of 800 rpm for 4 h. Then the solution was placed in a -80 °C refrigerator and frozen for 24 h. When the solution was completely frozen, it was placed in a -80 °C freeze dryer for vacuum drying. Finally, after grinding, pulverizing and sieving, a chlortetracycline hydrochloride inclusion complex was obtained;

[0082] All of the prepared chlortetracycline hydrochloride inclusion complex was added to 60 mL of water for injection; then 15 mL

[0083] Mix N,N-dimethylformamide and 10 mL of polyethylene glycol 600 evenly; adjust the pH to 4.15 with PBS buffer solution to obtain chlortetracycline hydrochloride inclusion complex injection, and obtain chlortetracycline hydrochloride injection preparation after filtering with a 0.22 μm PVDF filter element; the volume concentration of chlortetracycline hydrochloride in the injection preparation is 5%.

[0084] Example 12

[0085] Based on Example 11, the difference between Example 12 and Example 11 is that PLGA is used instead of hydroxypropyl-β-cyclodextrin; the volume concentration of chlortetracycline hydrochloride in the injection preparation is 5%.

[0086] Example 13

[0087] Based on Example 11, the difference between Example 13 and Example 11 is that Apisolex TM is used instead of polyvinylpyrrolidone K30; the volume concentration of chlortetracycline hydrochloride in the injection preparation is 5%.

[0088] Example 14

[0089] Based on Example 11, the difference between Example 14 and Example 11 is that Apisolex TM is used instead of polyvinylpyrrolidone K30 and PLGA is used instead of hydroxypropyl-β-cyclodextrin; the volume concentration of chlortetracycline hydrochloride in the injection preparation is 5%.

[0090] Comparative Example 1

[0091] Dissolve 3 g of chlortetracycline hydrochloride in 300 mL of ethanol to obtain a chlortetracycline hydrochloride solution;

[0092] Dissolve 10 g of β-cyclodextrin in 50 mL of distilled water to obtain an aqueous solution of the coating material;

[0093] Mix the obtained chlortetracycline hydrochloride solution and the aqueous solution of the coating material, stir magnetically at a speed of 800 rpm for 4 h to mix evenly, then place it in a rotary evaporator and evaporate the organic solvent at 60 °C and a pressure of -80 mPa for 10 min. After the evaporation of the organic solvent is completed, place the solution in a -80 °C refrigerator and freeze it for 24 h. When the solution is completely frozen, place it in a -80 °C freeze dryer for 24 h to complete vacuum drying. Finally, obtain the solid powder of chlortetracycline hydrochloride inclusion complex after grinding, pulverizing and sieving;

[0094] Add all the obtained solid powder of chlortetracycline hydrochloride inclusion complex to 70 mL of injection water; then add 15 mL of N,N-dimethylformamide and 10 mL of polyethylene glycol 600 and stir evenly; adjust the pH to 4.15 with PBS buffer solution to obtain chlortetracycline hydrochloride inclusion complex injection, and obtain chlortetracycline hydrochloride injection preparation after filtering with a 0.22 μm PVDF filter element;

[0095] The obtained injection solution was turbid, and the chlortetracycline hydrochloride inclusion complex could not be completely dissolved.

[0096] Comparative Example 2

[0097] Based on Comparative Example 1, the difference between Comparative Example 2 and Comparative Example 1 was that sulfobutyl-β-cyclodextrin was used instead of β-cyclodextrin; the obtained injection solution was turbid, and the chlortetracycline hydrochloride inclusion complex could not be completely dissolved.

[0098] Comparative Example 3

[0099] 5 g of chlortetracycline hydrochloride and 5 g of polyvinyl alcohol were placed in a grinding jar, and 16 grinding beads of different sizes (diameter 2 - 15 mm) were added. It was ground in a media mill at a rotation speed of 350 rpm for 1 h, and the solid dispersion was obtained through sieving. The obtained solid dispersion was dissolved in 300 mL of water to obtain a drug solution;

[0100] 10 g of hydroxypropyl-β-cyclodextrin was dissolved in 50 mL of distilled water to obtain an aqueous solution of the coating material;

[0101] The obtained drug solution and the aqueous solution of the coating material were mixed and sufficiently stirred evenly under the action of magnetic stirring at a rotation speed of 800 rpm for 4 h. Subsequently, the solution was placed in a -80 °C refrigerator and frozen for 24 h. When the solution was completely frozen, it was placed in a -80 °C freeze dryer to complete vacuum drying. Finally, after grinding, pulverizing, and sieving, the chlortetracycline hydrochloride inclusion complex was obtained;

[0102] All of the prepared chlortetracycline hydrochloride inclusion complex was added to 60 mL of injection water; subsequently, 15 mL of N,N-dimethylformamide and 10 mL of polyethylene glycol 600 were added and stirred evenly; the pH was adjusted to 4.15 with PBS buffer solution to obtain an injection of chlortetracycline hydrochloride inclusion complex. After filtration with a 0.22 μm PVDF filter element, a chlortetracycline hydrochloride injection preparation was obtained; the obtained injection solution was turbid, and the chlortetracycline hydrochloride inclusion complex could not be completely dissolved.

[0103] Comparative Example 4

[0104] Based on Comparative Example 3, the difference between Comparative Example 4 and Comparative Example 3 was that ethyl cellulose was used instead of polyvinyl alcohol; the obtained injection solution was turbid, and the chlortetracycline hydrochloride inclusion complex could not be completely dissolved.

[0105] Comparative Example 5

[0106] Based on Comparative Example 3, the difference between Comparative Example 5 and Comparative Example 3 was that HS15 was used instead of polyvinyl alcohol; the obtained injection solution was turbid, and the chlortetracycline hydrochloride inclusion complex could not be completely dissolved.

[0107] Comparative Example 6

[0108] Taking Comparative Example 3 as a reference, the difference between Comparative Example 6 and Comparative Example 3 is the use of Crodasol TM HS HP to replace polyvinyl alcohol; the resulting injection solution is turbid and the chlortetracycline hydrochloride clathrate cannot be completely dissolved.

[0109] Comparative Example 7

[0110] Taking Comparative Example 3 as a reference, the difference between Comparative Example 7 and Comparative Example 3 is the use of PLGA to replace hydroxypropyl-β-cyclodextrin; the resulting injection solution is turbid and the chlortetracycline hydrochloride clathrate cannot be completely dissolved.

[0111] Comparative Example 8

[0112] Taking Comparative Example 3 as a reference, the difference between Comparative Example 8 and Comparative Example 3 is the use of ethylcellulose to replace polyvinyl alcohol and the use of PLGA to replace hydroxypropyl-β-cyclodextrin; the resulting injection solution is turbid and the chlortetracycline hydrochloride clathrate cannot be completely dissolved.

[0113] Comparative Example 9

[0114] Taking Comparative Example 3 as a reference, the difference between Comparative Example 9 and Comparative Example 3 is the use of HS15 to replace polyvinyl alcohol and the use of PLGA to replace hydroxypropyl-β-cyclodextrin; the resulting injection solution is turbid and the chlortetracycline hydrochloride clathrate cannot be completely dissolved.

[0115] Comparative Example 10

[0116] Taking Comparative Example 3 as a reference, the difference between Comparative Example 10 and Comparative Example 3 is the use of Crodasol TM HS HP to replace polyvinyl alcohol and the use of PLGA to replace hydroxypropyl-β-cyclodextrin; the resulting injection solution is turbid and the chlortetracycline hydrochloride clathrate cannot be completely dissolved.

[0117] Comparative Example 11

[0118] Place 5 g of chlortetracycline hydrochloride, 5 g of polyvinylpyrrolidone K30 and 5 g of Apisolex TM in a grinding jar, put 16 grinding beads of different sizes (diameter 2 - 15 mm), grind in a media mill at a speed of 350 rpm for 1 h, obtain a solid dispersion through sieving, and dissolve the obtained solid dispersion in 300 mL of water to obtain a drug solution;

[0119] Dissolve 10 g of hydroxypropyl-β-cyclodextrin in 50 mL of distilled water to obtain an aqueous solution of the coating material;

[0120] The obtained drug solution was mixed with the aqueous solution of the coating material and magnetically stirred at a speed of 800 rpm for 4 h to be fully stirred evenly. Subsequently, the solution was placed in a -80 °C refrigerator and frozen for 24 h. When the solution was completely frozen, it was placed in a -80 °C freeze dryer to complete vacuum drying. Finally, the chlortetracycline hydrochloride inclusion complex was obtained after grinding, pulverizing, and sieving; all of the prepared chlortetracycline hydrochloride inclusion complex was added to 60 mL of water for injection; then 15 mL of N,N-dimethylformamide and 10 mL of polyethylene glycol 600 were added and stirred evenly; the pH was adjusted to 4.15 with PBS buffer solution to obtain the chlortetracycline hydrochloride inclusion complex injection solution, and the chlortetracycline hydrochloride injection preparation was obtained after filtration with a 0.22 μm PVDF filter element;

[0121] The obtained injection solution was turbid, and the chlortetracycline hydrochloride inclusion complex could not be completely dissolved.

[0122] Comparative Example 12

[0123] Based on Comparative Example 11, the difference between Comparative Example 12 and Comparative Example 11 was that PLGA was used instead of hydroxypropyl-β-cyclodextrin; the obtained injection solution was turbid, and the chlortetracycline hydrochloride inclusion complex could not be completely dissolved.

[0124] Application Example 1

[0125] According to the relevant requirements of the "Technical Guidelines for the Study of Drug Irritation, Hypersensitivity, and Hemolysis", the chlortetracycline hydrochloride injection preparations described in Examples 5 and 11 and Comparative Examples 1 and 3 were used for the study of muscle irritation in rabbits.

[0126] Twenty-four healthy rabbits were randomly divided into four groups, namely Group A, Group B, Group C, and Group D, with 6 rabbits in each group. The preparation obtained in Example 5 was injected into Group A, the preparation obtained in Example 11 was injected into Group B, the injection solution obtained in Comparative Example 1 was injected into Group C, and the injection solution obtained in Comparative Example 3 was injected into Group D;

[0127] During injection, the blood vessels should be avoided. At the anterior side of the thigh, at the midpoint between the knee joint and the femoral joint, the needle was inserted vertically 1 cm into the muscle, and the injection was slowly pushed at a speed of 1 mL / 10 s. After injection, the needle was quickly withdrawn, and the injection site was not massaged. The same amount of normal saline was injected into the right quadriceps femoris muscle in the same way; after administration, the experimental animals and the injection site were examined every day to observe the general condition of the rabbits and check for local reactions such as swelling, congestion, and exudation at the injection site.

[0128] At 2, 7, and 14 days after administration, 2 rabbits in each group were randomly selected and sacrificed by injecting air into the marginal ear vein. The quadriceps femoris muscle was dissected, longitudinally incised, and observed for pathological changes such as congestion, edema, exudation, hardening, or necrosis at the injection site; it was fixed by soaking in 10% formalin to make pathological sections, and the necrosis and infiltration of inflammatory cells in the quadriceps femoris muscle were observed under a microscope.

[0129] Score according to the muscle irritation reaction and injection reaction rating criteria described in Table 1, evaluate the degree of muscle irritation, calculate the total muscle irritation reaction level and determine the irritation level. The results are shown in Table 2.

[0130] Table 1 Muscle irritation reaction and injection reaction rating criteria

[0131]

[0132]

[0133] Table 2 Total muscle irritation reaction level and irritation level

[0134]

[0135] It can be found from Table 2 that when the chlortetracycline hydrochloride injection preparations prepared in Examples 5 and 11 are administered, there are no obvious reactions in the administered parts of the rabbits observed by naked eyes and light microscopy; while after administering the chlortetracycline hydrochloride injection preparations prepared in Comparative Examples 1 and 3, slight congestion appears in the administered parts, showing certain irritation. This indicates the safety of the injection provided by the present invention.

[0136] Application Example 2 Stability study of chlortetracycline hydrochloride injection preparation

[0137] Method: The chlortetracycline hydrochloride injection preparations prepared in Examples 5 and 11 and Comparative Examples 1 and 3 of the present invention were placed for 6 months under the conditions of temperature 40±2°C and relative humidity 70±5%. Samples were taken once at the end of the 0th month, 1st month, 2nd month, 3rd month, and 6th month, and the properties and contents of the chlortetracycline hydrochloride injection preparations were recorded. The recording results are shown in Table 3.

[0138] Table 3 Properties and contents of chlortetracycline hydrochloride injection preparation

[0139]

[0140]

[0141] Note: The normal range of the content labeled amount is 90-110%.

[0142] It can be found from Table 3 that in the accelerated stability study of the chlortetracycline hydrochloride injection preparations prepared in Examples 5 and 11, the drug contents from 0 to 6 months are all within the normal range of the labeled amount, indicating good stability of the injection; while for the chlortetracycline hydrochloride injection preparations prepared in Comparative Examples 1 and 3, the drug contents from 0 to 6 months show a downward trend and are lower than 90% of the normal range of the labeled amount, indicating poor stability of the injection.

[0143] Application Example 3 Pharmacodynamic evaluation test of chlortetracycline hydrochloride injection preparation

[0144] A total of 36 Liangfeng chickens weighing 550 ± 25 g were selected and divided into 3 groups, namely the model group, drug control group A, and drug control group B, with 12 chickens in each group;

[0145] The model group was not given any treatment;

[0146] Drug control group A was given 10 mg / kg of the sample in Example 5 by intramuscular injection;

[0147] Drug control group B was given 10 mg / kg of florfenicol injection from Jixing Company by intramuscular injection;

[0148] After 3 days of treatment, the animals were observed for one week, and animal tissues (heart, liver, spleen, lungs, and kidneys) were collected. After H&E staining, the tissue lesions were observed under a microscope. The results are shown in Figure 1 .

[0149] Through Figure 1 It can be found that the tissues of the Liangfeng chickens in the model group all showed varying degrees of lesions. After treatment with the chlortetracycline hydrochloride injection preparation, it was found that the hearts, livers, and spleens of the chickens were effectively improved, and there was slight congestion in the lungs and kidneys, which may be related to the severity of the infection itself. In contrast, for the florfenicol injection, although each tissue was improved to varying degrees after treatment, compared with the chlortetracycline hydrochloride injection preparation, the lesion phenomenon was obvious, indicating that the chlortetracycline hydrochloride injection preparation has a significantly better treatment effect than the florfenicol injection.

[0150] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A chlortetracycline hydrochloride inclusion compound, characterized in that: Its raw materials include chlortetracycline hydrochloride and coating materials; The molar ratio of chlortetracycline hydrochloride to the coating material is 1:0.25-2; The coating material comprises at least one of β-cyclodextrin, hydroxypropyl-β-cyclodextrin, sulfobutyl-β-cyclodextrin and PLGA.

2. The chlortetracycline hydrochloride inclusion compound according to claim 1, characterized in that: The raw materials also include hydrophilic polymers; the hydrophilic polymers include polyvinyl alcohol, povidone K30, ethyl cellulose, Apisolex TM , HS15 and Crodasol TM At least one of HS and HP; the molar ratio of chlortetracycline hydrochloride to the hydrophilic polymer is 1:0.05-1.

3. The method for preparing the chlortetracycline hydrochloride inclusion compound according to any one of claims 1 or 2, characterized in that: The following steps are involved: The chlortetracycline hydrochloride, the organic solvent and the aqueous solution of the coating material are mixed, and then heated, frozen and dried in sequence to obtain the chlortetracycline hydrochloride inclusion complex.

4. The preparation method according to claim 3, characterized in that: The organic solvent comprises at least one of ethanol, methanol and acetonitrile, and the dosage ratio of the chlortetracycline hydrochloride to the organic solvent is 1g:100-300mL.

5. The preparation method according to claim 3, characterized in that: When the raw material includes a hydrophilic polymer, the preparation method of the chlortetracycline hydrochloride inclusion compound includes the following steps: mixing chlortetracycline hydrochloride and the hydrophilic polymer and then ball milling to obtain a solid dispersion; mixing the solid dispersion with water to obtain a drug solution; The drug solution is mixed with the coating material aqueous solution, and then frozen and dried in sequence to obtain the chlortetracycline hydrochloride inclusion complex.

6. Use of the chlortetracycline hydrochloride inclusion complex according to any one of claims 1 or 2 or the chlortetracycline hydrochloride inclusion complex prepared by the preparation method according to any one of claims 3 to 5 in the preparation of chlortetracycline hydrochloride injection preparations.

7. A chlortetracycline hydrochloride injection preparation, characterized in that: Calculated by volume, the preparation comprises 25 to 50 parts of cosolvent and 60 to 70 parts of water. The volume concentration of chlortetracycline hydrochloride in the chlortetracycline hydrochloride injection preparation is 1.5 to 8%.

8. The chlortetracycline hydrochloride injection preparation according to claim 7, characterized in that: The cosolvent comprises at least one of N,N-dimethylformamide, polyethylene glycol, Tween 80, sodium carboxymethyl cellulose and 1.2-propylene glycol; the pH of the chlortetracycline hydrochloride injection preparation is 4-5.

9. The chlortetracycline hydrochloride injection preparation according to claim 7, characterized in that: When the raw material of the chloramphenicol hydrochloride inclusion complex does not contain a hydrophilic polymer, the volume concentration of chloramphenicol hydrochloride in the chloramphenicol hydrochloride injection preparation is 1.5-3%; when the raw material of the chloramphenicol hydrochloride inclusion complex contains a hydrophilic polymer, the volume concentration of chloramphenicol hydrochloride in the chloramphenicol hydrochloride injection preparation is 3-8%.

10. Use of the chlortetracycline hydrochloride injection preparation according to any one of claims 7 to 9 in antibacterial applications.

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