Polysubstituted cyclodextrin supramolecular material, preparation method and application thereof, and pharmaceutical composition

Abstract

The invention discloses a multi-substituted cyclodextrin supramolecular material as well as a preparation method and application thereof and a pharmaceutical composition, and relates to the technical field of supramolecular materials, and the multi-substituted cyclodextrin supramolecular material is obtained by coordination of multi-substituted cyclodextrin and metal ions. The CD-pMOF prepared by the preparation method disclosed by the invention has relatively strong drug loading capacity, and shows an excellent protective effect on unstable drugs; and the prepared CD-pMOFs with different sizes respectively have relatively good upper respiratory tract and lung deposition effects, and have wide application prospects in inhalation drug delivery systems.

Description

Technical Field

[0001] The present invention relates to the technical field of supramolecular materials, and particularly relates to a multi-substituted cyclodextrin supramolecular material, a preparation method and use thereof, and a pharmaceutical composition. Background Art

[0002] Supramolecular materials are a class of material systems with specific structures and functions formed based on non-covalent intermolecular interactions (such as hydrogen bonds, van der Waals forces, electrostatic interactions, π-π stacking, hydrophobic interactions, etc.). The types of supramolecular materials are rich and diverse, including metal-organic frameworks (MOFs), organic covalent frameworks (COFs), hydrogen-bonded supramolecular systems, crown ether supramolecular systems, and supramolecular polymers. The core lies in the dynamic reversible binding between molecules, rather than the covalently fixed structure of traditional materials. This characteristic endows them with unique self-assembly capabilities, environmental responsiveness, and adjustable properties, and they are widely used in the fields of biomedicine, energy, environment, and materials.

[0003] Although natural cyclodextrins have unique molecular structures and good drug inclusion capabilities, due to limitations in aspects such as water solubility and safety, they often cannot meet the requirements of some applications. Multi-substituted cyclodextrins refer to derivatives formed by chemically modifying the hydroxyl groups of natural cyclodextrin molecules (including α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin) and introducing specific functional groups or substituents (such as hydroxypropyl, sulfobutyl, carboxymethyl, etc.). The number and position distribution of substituents in multi-substituted cyclodextrins are non-uniform, resulting in their substituent polydispersity characteristics and different degrees of substitution. The introduction of specific functional groups or substituents makes multi-substituted cyclodextrins have good water solubility, thermal stability, and biocompatibility, and they are widely used in the pharmaceutical field in injectables, oral preparations, etc.

[0004] Multi-substituted cyclodextrins exhibit more excellent properties in aspects such as drug controlled release, improving drug solubility and drug loading capacity, and can overcome some disadvantages of natural cyclodextrins in drug delivery. For example, hydroxypropyl-β-cyclodextrin (HP-β-CD) can significantly improve its water solubility (about 30 times) and drug inclusion capacity by introducing hydroxypropyl groups into β-cyclodextrin, and it has high biological safety and low toxicity. In addition, during the preparation process of multi-substituted cyclodextrins, due to the complexity of the substitution reaction, the number, position, and distribution of substituents in the resulting product molecules are different, making the final product not a single entity with a definite structure, but a mixture composed of a series of molecules with similar but not completely identical structures. This compositional non-uniformity endows multi-substituted cyclodextrins with polydispersity and high structural complexity, which brings rich functional groups and reaction sites to multi-substituted cyclodextrins and enables them to have multifunctionality. Therefore, multi-substituted cyclodextrins show broader application prospects in drug delivery and other biomedical applications.

[0005] At present, cyclodextrin metal-organic frameworks (CD-MOFs) are usually constructed (to form a crystal structure) based on natural cyclodextrins with a periodic structure as organic ligands. Although patents have mentioned that multi-substituted cyclodextrins can also be used as organic ligands, it has been found that it is difficult to form crystalline CD-MOFs based on multi-substituted cyclodextrins. Instead, due to their polydispersity, disordered structures are formed. As an amorphous CD-MOF is used as a drug carrier, its drug loading capacity and release capacity for drug molecules are significantly different, providing a better choice of carrier excipients for special needs such as inhaled drug delivery. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a multi-substituted cyclodextrin supramolecular material and a preparation method thereof, and the obtained multi-substituted cyclodextrin supramolecular material (CD-pMOF) can be used as a drug carrier in a drug delivery system.

[0007] The technical problem to be solved by the present invention is achieved by the following technical solutions:

[0008] One object of the present invention is to provide a multi-substituted cyclodextrin supramolecular material obtained by coordinating a multi-substituted cyclodextrin with metal ions.

[0009] Further, the multi-substituted cyclodextrin is a derivative obtained by substituting hydroxyl groups on cyclodextrin with different groups, including but not limited to at least one of hydroxypropyl-β-cyclodextrin, sulfobutyl ether-β-cyclodextrin, methylated-β-cyclodextrin, acetylated-β-cyclodextrin, carboxymethyl-β-cyclodextrin, and hydroxyethyl-β-cyclodextrin.

[0010] Further, the degree of substitution of the multi-substituted cyclodextrin is 1 to 21. Preferably, the degree of substitution of the hydroxypropyl-β-cyclodextrin is 2.8 to 10.5; the degree of substitution of the sulfobutyl ether-β-cyclodextrin is 4 to 10. The degree of substitution (DS) of the multi-substituted cyclodextrin refers to the number of hydroxyl groups substituted on each cyclodextrin on average.

[0011] Further, the metal ions include but not limited to Na + 、Li + 、K + 、Rb + 、Cs + 、Mg 2+ 、Ag + 、Ca 2+ and at least one of them.

[0012] Further, the coordination molar ratio of the multi-substituted cyclodextrin to the metal ions is 1:(0.5 to 8).

[0013] Furthermore, the multi-substituted cyclodextrin supramolecular material has a spherical morphology, which endows it with a larger specific surface area, better dispersibility, and a more uniform particle size distribution.

[0014] Furthermore, the multi-substituted cyclodextrin supramolecular material has an amorphous structure, which endows it with higher flexibility and plasticity, making it advantageous in some applications that require material deformation or adaptation to complex environments, such as drug delivery.

[0015] The second object of the present invention is to provide a preparation method of a multi-substituted cyclodextrin supramolecular material, comprising the following steps:

[0016] (1) Dissolve the multi-substituted cyclodextrin and metal ions in a first solvent to obtain a mixed solution;

[0017] (2) Perform post-treatment on the mixed solution prepared in step (1), wash, and dry to obtain the multi-substituted cyclodextrin supramolecular material.

[0018] Furthermore, the molar ratio of the multi-substituted cyclodextrin to the metal ions in the feed is 1:(0.5 - 10), preferably 1:(1 - 4).

[0019] Furthermore, the first solvent includes but is not limited to at least one of water, methanol, ethanol, propanol, and propylene glycol, preferably methanol.

[0020] Furthermore, the concentration of the multi-substituted cyclodextrin in the mixed solution is 0.01 - 0.4 mol / L; the concentration of the metal ions in the mixed solution is 0.02 - 0.8 mol / L.

[0021] Furthermore, the solvent for washing includes but is not limited to at least one of isopropanol, acetone, dichloromethane, ethyl acetate, and n-hexane, preferably acetone.

[0022] Furthermore, the drying temperature is 50 - 90 °C, preferably 60 - 70 °C.

[0023] Furthermore, the post-treatment method includes but is not limited to one of the hot saturated solution cooling method, anti-solvent addition method, solvent diffusion method, and solvent evaporation method.

[0024] In the present invention, the CD-pMOF prepared by the hot saturated solution cooling method has a spherical morphology and an amorphous structure, and the CD-pMOF prepared by the anti-solvent addition method, solvent diffusion method, and solvent evaporation method has an irregular morphology and an amorphous structure.

[0025] As a specific embodiment, in the hot saturated solution cooling method, a second solvent is added dropwise to the mixed solution under heating conditions until white turbidity appears in the solution, and then the addition is stopped and the temperature is cooled. Among them, the second solvent includes but is not limited to at least one of isopropanol, acetone, dichloromethane, chloroform, ethyl acetate, n-hexane, and ether. The heating temperature is 50-90°C, preferably 60-70°C. The cooling includes two methods: direct cooling and gradient cooling. The cooling temperature is -20°C to room temperature, preferably -20 to 4°C; the cooling time is 0.5-8 h, preferably 2-4 h.

[0026] As a specific embodiment, in the anti-solvent addition method, a second solvent is added dropwise to the mixed solution at a certain temperature, and precipitation occurs. Among them, the second solvent includes but is not limited to at least one of isopropanol, acetone, dichloromethane, chloroform, ethyl acetate, n-hexane, and ether. The certain temperature is low temperature (0-4°C), room temperature or heating (40-60°C).

[0027] As a specific embodiment, in the solvent diffusion method, an open container I containing the mixed solution and an open container II containing the second solvent are jointly placed in a sealed system, and the sealed system is heated so that the third solvent in the open container II gradually evaporates and diffuses into the mixed solution in the open container I. Among them, the third solvent includes but is not limited to at least one of acetone, dichloromethane, and ether. The heating temperature is 40-60°C.

[0028] As a specific embodiment, in the solvent evaporation method, the mixed solution is placed in an open container, and after adding the fourth solvent, it is heated so that the first solvent in the open container gradually evaporates. Among them, the fourth solvent includes but is not limited to at least one of isopropanol, chloroform, ethyl acetate, and n-hexane. The heating temperature is 40-60°C.

[0029] The third object of the present invention is to provide the use of the multi-substituted cyclodextrin supramolecular material as a drug carrier.

[0030] The fourth object of the present invention is to provide a pharmaceutical composition, comprising the multi-substituted cyclodextrin supramolecular material and an active ingredient loaded on the multi-substituted cyclodextrin supramolecular material.

[0031] Furthermore, the weight ratio of the active ingredient to the multi-substituted cyclodextrin supramolecular material is 0.001-30%, preferably 0.1-20%.

[0032] Furthermore, the active ingredient is a drug for treating lung diseases, such as glucocorticoids, anti-inflammatory drugs, antibacterial drugs, antiviral drugs, and active ingredients of traditional Chinese medicine, including but not limited to at least one of budesonide, dexamethasone, curcumin, quercetin, luteolin, resveratrol, paeonol, baicalein, eucalyptol, D-limonene, α-pinene, and eugenol.

[0033] Furthermore, the active ingredient is a drug for treating upper respiratory diseases, such as glucocorticoids, anti-inflammatory drugs, antibacterial drugs, antiviral drugs, and active ingredients of traditional Chinese medicine, including but not limited to at least one of budesonide, mometasone furoate, iodine, L-menthol, baicalein, berberine, eucalyptol, D-limonene, α-pinene, and eugenol.

[0034] Furthermore, the dosage forms of the pharmaceutical composition include liquid preparations, solid preparations, semi-solid preparations, and gas preparations, and the administration routes include gastrointestinal administration, injection administration, transdermal administration, inhalation administration, mucosal administration, rectal administration, etc., such as granules, tablets, pills, suspensions, patches, capsules, sprays, dry powder inhalers, nasal powders, aerosols, solutions, injections, poultices, etc.

[0035] The beneficial effects of the present invention are as follows:

[0036] 1. The present invention provides a method for self-assembling metal-organic framework materials based on the coordination of multi-substituted cyclodextrin and metal ions. The prepared CD-pMOF has good solubility, biocompatibility, and stability; different from the conventional preparation methods of existing CD-MOFs (such as vapor diffusion method, solvothermal method, ultrasonic / microwave-assisted method), the CD-pMOF prepared by the hot saturated solution cooling method in the present invention has a spherical morphology and an amorphous structure, which is significantly different from the cubic or rod-like morphology and crystal structure of existing CD-MOFs.

[0037] 2. The CD-pMOF prepared by the present invention has strong drug-loading capacity and shows excellent protection for unstable drugs; and the prepared CD-pMOFs with different sizes respectively have better deposition effects in the upper respiratory tract and lungs, and have broad application prospects in the inhalation drug delivery system.

[0038] 3. The CD-pMOF prepared by the present invention can not only be used as a drug carrier, which helps to improve the performance of existing drug delivery systems, but also enriches the types and morphologies of cyclodextrin supramolecular materials, and regulates the material properties to meet the needs of different fields. Description of the Drawings

[0039] Figure 1 It is the scanning electron microscope images of NaAc-CD-pMOF I and NaAc-CD-pMOF II in Example 1;

[0040] Figure 2 Particle size distribution diagrams of NaAc-CD-pMOF I and NaAc-CD-pMOF II in Example 1;

[0041] Figure 3 Scanning electron microscope images of NaAc-CD-pMOF I prepared with HP-β-CD with different degrees of substitution in Example 2;

[0042] Figure 4 Scanning electron microscope images and micrographs of CD-pMOF prepared with different metal salts in Example 3;

[0043] Figure 5 Micrograph of NaI-CD-pMOF III prepared with SEB-β-CD as the organic ligand in Example 4;

[0044] Figure 6 Scanning electron microscope images of CD-pMOF IV prepared by the antisolvent method, solvent diffusion method, and solvent evaporation method in Example 5;

[0045] Figure 7 Powder X-ray diffraction pattern (A), Fourier transform infrared spectrum (B), thermogravimetric analysis chart (C), nitrogen isothermal adsorption and desorption curve (D), pore size distribution diagram (E), and small-angle scattering curve (E) of CD-pMOF in Example 6;

[0046] Figure 8 Coordination molar ratio relationship between HP-β-CD and NaAc in NaAc-CD-pMOF I prepared with different feed molar ratios (A) and different degrees of substitution (B) in Example 6;

[0047] Figure 9 Coordination modes of HP-β-CD with sodium ions when the substitution position on the glucose unit of HP-β-CD is C2 (A), C3 (B), and C6 (C) in Example 6;

[0048] Figure 10 Hypothesis of multiple coordination modes of sodium ions in Example 6;

[0049] Figure 11 Hypothesis of supramolecular structural units of CD-pMOF in Example 6;

[0050] Figure 12 Scanning electron microscope images of Eug@CD-pMOF in Example 7;

[0051] Figure 13 Particle size distribution diagram (A), Fourier transform infrared spectrum (B), Raman spectrum (C), and high-temperature stability evaluation (D) of Eug@CD-pMOF in Example 7;

[0052] Figure 14 For the hypothesis of the Eug@CD-pMOF supramolecular structural unit in Example 7;

[0053] Figure 15 For the in vitro deposition distribution maps of CD-pMOF I and Eug@CD-pMOF I in Example 7;

[0054] Figure 16 For the in vitro deposition distribution maps of CD-pMOF II and Eug@CD-pMOF II in Example 7;

[0055] Figure 17 For the histopathological sections of the throat and lung tissues of rats after inhalation administration of Eug@CD-pMOF in Example 7;

[0056] Figure 18 For the particle size distribution map of I2@CD-pMOF II in Example 8;

[0057] Figure 19 For the Fourier transform infrared spectrum (A) and Raman spectrum (B) of I2@CD-pMOF II in Example 8;

[0058] Figure 20 For the high-temperature stability evaluation (A) and high-humidity stability evaluation (B) of I2@CD-pMOF II in Example 8;

[0059] Figure 21 For the in vitro deposition distribution of I2@CD-pMOF II in Example 8;

[0060] Figure 22 For the hemolytic safety evaluation of I2@CD-pMOF II in Example 8. Detailed implementation manners

[0061] In order to make the technical means, creative features, achieved purposes and effects of the present invention easy to understand, the present invention will be further described below in conjunction with specific embodiments and diagrams.

[0062] Unless otherwise defined, all technical terms and scientific terms used in the present invention have the same meanings as those commonly understood by those of ordinary skill in the art to which the present invention belongs.

[0063] In the present invention, "room temperature" refers to a temperature of 4 - 40 °C, preferably 25 ± 5 °C; HP-β-CD refers to hydroxypropyl-β-cyclodextrin; SBE-β-CD refers to sulfobutyl-β-cyclodextrin; NaAc refers to sodium acetate; NaI refers to sodium iodide; NaCl refers to sodium chloride; KAc refers to potassium acetate; KI refers to potassium iodide; NaOH refers to sodium hydroxide; KOH refers to potassium hydroxide; HPMC refers to hydroxypropyl methylcellulose.

[0064] In the present invention, CD-pMOF I refers to a spherical CD-pMOF based on HP-β-CD as a multi-substituted cyclodextrin, which is precipitated by the method of cooling a hot saturated solution in an ice-water bath at 4°C; CD-pMOF II refers to a spherical CD-pMOF based on HP-β-CD as a multi-substituted cyclodextrin, which is precipitated by the method of cooling a hot saturated solution in a refrigerator at -20°C; CD-pMOF III refers to a spherical CD-pMOF based on SBE-β-CD as a multi-substituted cyclodextrin, which is precipitated by the method of cooling a hot saturated solution in an ice-water bath at 4°C; CD-pMOF IV refers to an irregular CD-pMOF prepared by the anti-solvent addition method / solvent diffusion method / solvent evaporation method.

[0065] Example 1

[0066] Preparation of spherical CD-pMOF with different particle sizes

[0067] Under the conditions of a temperature of 60°C and a stirring speed of 500 rpm, 1.408 g of HP-β-CD (degree of substitution 4.71) and 0.164 g of NaAc (molar ratio of HP-β-CD to NaAc is 1:2) were dissolved in 15 mL of methanol, and then isopropanol was added dropwise. During the addition process, the state of the solution was observed. When a milky turbidity appeared in the solution, the solution was in a hot saturated state at this time, and the addition was immediately stopped. The solution was quickly transferred to an ice-water bath at 4°C and a refrigerator at -20°C respectively and allowed to stand for 2 h. The supernatant was discarded, centrifuged at 4000 rpm for 5 min, washed with acetone (10 mL × 3), and dried in a forced-air drying oven at 70°C for 2 h to obtain NaAc-CD-pMOF I and NaAc-CD-pMOF II.

[0068] As Figure 1 and Figure 2 shown, both NaAc-CD-pMOF I and NaAc-CD-pMOF II are spherical in shape. Among them, NaAc-CD-pMOF I has a smaller particle size, and the particle size D50 and D90 are 2.42 μm and 4.67 μm respectively; NaAc-CD-pMOF II has a larger particle size, and the particle size D50 and D90 are 5.75 μm and 10.91 μm respectively.

[0069] Example 2

[0070] Preparation of spherical CD-pMOF with different degrees of substitution

[0071] Under the conditions of a temperature of 60 °C and a stirring speed of 500 rpm, HP-β-CD with degrees of substitution of 4.56, 4.71, 5.55, 5.59, and 6.19 (corresponding masses of 1.399 g, 1.408 g, 1.457 g, 1.459 g, and 1.494 g respectively) and 0.164 g of NaAc (the molar ratio of HP-β-CD to NaAc is 1:2) were dissolved in 15 mL of methanol, and then isopropanol was added dropwise. During the addition process, the state of the solution was observed. When a milky white turbidity appeared in the solution, the solution was in a hot saturated state, and the addition was immediately stopped. The solution was quickly transferred to a 4 °C ice-water bath and allowed to stand for 2 h. The supernatant was discarded, and it was centrifuged at 4000 rpm for 5 min, washed with acetone (10 mL × 3), and dried in a forced-air drying oven at 70 °C for 2 h to obtain NaAc-CD-pMOF I.

[0072] As Figure 3 shown, NaAc-CD-pMOF I prepared with HP-β-CD with different degrees of substitution was in a spherical morphology.

[0073] Example 3

[0074] 1. Preparation of spherical CD-pMOF using NaI as the metal salt

[0075] Under the conditions of a temperature of 60 °C and a stirring speed of 500 rpm, 2.988 g of HP-β-CD (degree of substitution of 6.19) and 0.5996 g of NaI (the molar ratio of HP-β-CD to NaI is 1:2) were dissolved in 25 mL of methanol, and then isopropanol was added dropwise. During the addition process, the state of the solution was observed. When a milky white turbidity appeared in the solution, the solution was in a hot saturated state, and the addition was immediately stopped. The solution was quickly transferred to a -20 °C refrigerator and allowed to stand for 2 h. The supernatant was discarded, and it was centrifuged at 4000 rpm for 5 min, washed with acetone (10 mL × 3), and dried in a forced-air drying oven at 70 °C for 2 h to obtain NaI-CD-pMOF II.

[0076] 2. Preparation of spherical CD-pMOF using NaCl as the metal salt

[0077] Under the conditions of a temperature of 50 °C and a stirring speed of 500 rpm, 1.408 g of HP-β-CD (degree of substitution is 4.71) and 0.117 g of NaCl (the molar ratio of HP-β-CD to NaCl is 1:2) were dissolved in 15 mL of methanol. Then, isopropanol was added dropwise. During the dropping process, the state of the solution was observed. When a milky white turbidity appeared in the solution, the solution was in a hot saturated state at this time, and the dropping was immediately stopped. The solution was quickly transferred to a 4 °C ice-water bath and allowed to stand for 2 h. The supernatant was discarded, and it was centrifuged at a speed of 4000 rpm for 5 min. The product was washed with acetone (10 mL × 3) and dried in a forced-air drying oven at 70 °C for 2 h to obtain NaCl-CD-pMOF I.

[0078] 3. Preparation of spherical CD-pMOF using KAc as the metal salt

[0079] Under the conditions of a temperature of 70 °C and a stirring speed of 500 rpm, 1.408 g of HP-β-CD (degree of substitution is 4.71) and 0.196 g of KAc (the molar ratio of HP-β-CD to KAc is 1:2) were dissolved in 15 mL of methanol. Then, isopropanol was added dropwise. During the dropping process, the state of the solution was observed. When a milky white turbidity appeared in the solution, the solution was in a hot saturated state at this time, and the dropping was immediately stopped. The solution was quickly transferred to a 4 °C ice-water bath and allowed to stand for 2 h. The supernatant was discarded, and it was centrifuged at a speed of 4000 rpm for 5 min. It was washed with acetone (10 mL × 3) and dried in a forced-air drying oven at 70 °C for 2 h to obtain KAc-CD-pMOF I.

[0080] 4. Preparation of spherical CD-pMOF using KI as the metal salt

[0081] Under the conditions of a temperature of 90 °C and a stirring speed of 500 rpm, 1.408 g of HP-β-CD (degree of substitution is 4.71) and 0.332 g of KI (the molar ratio of HP-β-CD to NaCl is 1:2) were dissolved in 40 mL of an ethanol-water solution (the volume ratio of ethanol to water is 95:5). Then, isopropanol was added dropwise. During the dropping process, the state of the solution was observed. When a milky white turbidity appeared in the solution, the solution was in a hot saturated state at this time, and the dropping was immediately stopped. The solution was quickly transferred to a 4 °C ice-water bath and allowed to stand for 2 h. The supernatant was discarded, and it was centrifuged at a speed of 4000 rpm for 5 min. It was washed with acetone (10 mL × 3) and dried in a forced-air drying oven at 70 °C for 2 h to obtain KI-CD-pMOF I.

[0082] 5. Preparation of spherical CD-pMOF using NaOH as the metal salt

[0083] Under the conditions of a temperature of 60 °C and a stirring speed of 500 rpm, 1.408 g of HP-β-CD (substitution degree 4.71) and 0.080 g of NaOH (molar ratio of HP-β-CD to NaOH is 1:2) were dissolved in 15 mL of methanol. Then, isopropanol was added dropwise. During the addition process, the state of the solution was observed. When a milky white turbidity appeared in the solution, the solution was in a hot saturated state at this time, and the addition was immediately stopped. The solution was quickly transferred to a 4 °C ice-water bath and allowed to stand for 2 h. The supernatant was discarded, centrifuged at 4000 rpm for 5 min, washed with acetone (10 mL × 3), and dried in a forced-air drying oven at 70 °C for 2 h to obtain NaOH-CD-pMOF I.

[0084] 6. Preparation of spherical CD-pMOF using KOH as the metal salt

[0085] Under the conditions of a temperature of 60 °C and a stirring speed of 500 rpm, 1.408 g of HP-β-CD (substitution degree 4.71) and 0.112 g of KOH (molar ratio of HP-β-CD to KOH is 1:2) were dissolved in 15 mL of methanol. Then, isopropanol was added dropwise. During the addition process, the state of the solution was observed. When a milky white turbidity appeared in the solution, the solution was in a hot saturated state at this time, and the addition was immediately stopped. The solution was quickly transferred to a 4 °C ice-water bath and allowed to stand for 2 h. The supernatant was discarded, centrifuged at 4000 rpm for 5 min, washed with acetone (10 mL × 3), and dried in a forced-air drying oven at 70 °C for 2 h to obtain KOH-CD-pMOF I.

[0086] As Figure 4 shown, the CD-pMOF prepared using different metal salts is in a spherical morphology.

[0087] Example 4

[0088] Preparation of spherical CD-pMOF using sulfobutyl ether-β-cyclodextrin as the organic ligand

[0089] Under the conditions of a temperature of 60 °C and a stirring speed of 500 rpm, 2.2 g of SBE-β-CD (substitution degree 5.46) and 1.2 g of NaI (molar ratio of SBE-β-CD to NaI is 1:8) were dissolved in 4 mL of pure water. Then, isopropanol was added dropwise. During the addition process, the state of the solution was observed. When a milky white turbidity appeared in the solution, the solution was in a hot saturated state at this time, and the addition was immediately stopped. After the solution was naturally cooled to room temperature, it was transferred to a 4 °C ice-water bath and allowed to stand for 2 h. The supernatant was discarded, centrifuged at 4000 rpm for 5 min, washed with isopropanol (10 mL × 3), and dried in a forced-air drying oven at 70 °C for 2 h to obtain NaI-CD-pMOF III.

[0090] As Figure 5As shown, NaI-CD-pMOF III prepared with sulfobutyl ether-β-cyclodextrin as the organic ligand is in a spherical morphology.

[0091] Example 5

[0092] 1. Preparation of irregular-shaped CD-pMOF by anti-solvent addition method

[0093] Under the conditions of a temperature of 60 °C and a stirring speed of 500 rpm, 1.408 g of HP-β-CD and 0.328 g of NaAc (the molar ratio of HP-β-CD to NaAc is 1:4) were dissolved in 10 mL of methanol and cooled to room temperature. 20 mL of isopropanol was slowly dropped into the mixed system under the condition of a stirring speed of 1000 rpm to obtain a large amount of white solid. The supernatant was discarded, centrifuged at 4000 rpm for 5 min, washed with acetone (10 mL × 3), and dried in a forced-air drying oven at 70 °C for 2 h to obtain NaAc-CD-pMOF IV.

[0094] 2. Preparation of irregular-shaped CD-pMOF by solvent diffusion method

[0095] Under the conditions of a temperature of 60 °C and a stirring speed of 500 rpm, 1.408 g of HP-β-CD and 0.328 g of NaAc (the molar ratio of HP-β-CD to NaAc is 1:4) were dissolved in 2 mL of water and cooled to room temperature. The solution was transferred to a beaker and placed in a wide-mouth bottle pre-filled with 50 mL of acetone (the height of the acetone does not exceed the height of the beaker). The wide-mouth bottle was sealed, and the sealed wide-mouth bottle was heated at 50 °C to allow the acetone to gradually evaporate and diffuse into the solution in the beaker. After 4 h, a white jelly-like substance was obtained. The supernatant was discarded, centrifuged at 4000 rpm for 5 min, washed with acetone (10 mL × 3), and dried in a forced-air drying oven at 70 °C for 2 h to obtain NaAc-CD-pMOF IV.

[0096] 3. Preparation of irregular-shaped CD-pMOF by solvent evaporation method

[0097] Under the conditions of a temperature of 60 °C and a stirring speed of 500 rpm, 1.408 g of HP-β-CD and 0.328 g of NaAc (the molar ratio of HP-β-CD to NaAc is 1:4) were dissolved in 15 mL of methanol, and then 15 mL of isopropanol was added, and the solvent was evaporated in an open state. After 4 h, a white jelly-like substance was obtained. The supernatant was discarded, centrifuged at 4000 rpm for 5 min, washed with acetone (10 mL × 3), and dried in a forced-air drying oven at 70 °C for 2 h to obtain NaAc-CD-pMOF IV.

[0098] As Figure 6As shown, the CD-pMOFs prepared by the anti-solvent addition method, solvent diffusion method, and solvent evaporation method are all irregular in shape.

[0099] Comparative Example 1

[0100] At a temperature of 60 °C and a stirring speed of 500 rpm, 1.408 g of HP-β-CD (substitution degree of 4.71) was dissolved in 15 mL of methanol, and then isopropanol was added dropwise. During the dropwise addition process, the solution state was observed. When a milky white turbidity appeared in the solution, the solution was in a hot saturated state at this time, and the dropwise addition was immediately stopped. The solution was quickly transferred to a 4 °C ice-water bath and allowed to stand for 2 h. The supernatant was discarded, centrifuged at 4000 rpm for 5 min, washed with acetone (10 mL × 3), and dried in a forced-air drying oven at 70 °C for 2 h to obtain the HP-β-CD control.

[0101] Comparative Example 2

[0102] HP-β-CD and NaAc were mixed evenly according to the coordination molar ratio of 1:1.32 in CD-pMOF to obtain a physical mixture of HP-β-CD and NaAc.

[0103] Example 6

[0104] 1. Structural Characterization of CD-pMOF

[0105] Structural characterizations were performed on the raw material HP-β-CD (Raw HP-β-CD), NaAc, NaAc-CD-pMOF I and NaAc-CD-pMOF II (CD-pMOF I and CD-pMOF II) prepared in Example 1, the HP-β-CD control (Control HP-β-CD) prepared in Comparative Example 1, and the physical mixture of HP-β-CD and NaAc (Physical mixture) prepared in Comparative Example 2.

[0106] A powder X-ray diffractometer (XRD) was used to measure NaAc, Raw HP-β-CD, Control HP-β-CD, CD-pMOF I, and Physical mixture. As Figure 7 (A) shows, CD-pMOF I has no obvious characteristic diffraction peaks and is in an amorphous state; while the diffraction peaks in the Physical mixture are at 8.9°, 23.0°, 30.1°, 43.1°, and 52.0°, which are consistent with the diffraction peaks of NaAc. This indicates that there is not a simple physical mixture between HP-β-CD and NaAc in CD-pMOF I, but a certain interaction has occurred, so CD-pMOF belongs to a new compound.

[0107] The infrared absorption spectra of NaAc, Raw HP-β-CD, Control HP-β-CD, CD-pMOFI, and Physical mixture were analyzed using a Fourier transform infrared absorption spectrometer (FTIR). As Figure 7 (B) shows, the stretching vibration peaks of -OH in Raw HP-β-CD and Control HP-β-CD are located at 3404.72 cm -1 and 3401.09 cm -1 , respectively, which are almost the same as the -OH absorption peak position of 3404.74 cm -1 in the Physical mixture. However, the -OH in CD-pMOF I shows a red shift to 3385.61 cm -1 , indicating that a coordination interaction has occurred between the -OCCO- binding sequence in HP-β-CD and Na + , strengthening the intermolecular hydrogen bonds.

[0108] The thermodynamic behaviors of NaAc, Raw HP-β-CD, Control HP-β-CD, CD-pMOFI, and Physical mixture were analyzed using a thermogravimetric analyzer. As Figure 7 (C) shows, the pyrolysis curve of CD-pMOF I is different from those of HP-β-CD and Physical mixture, indicating that CD-pMOF I has different thermodynamic behaviors and physicochemical properties from HP-β-CD, thus reflecting the formation of a new spatial structure in CD-pMOF I.

[0109] The specific surface areas and pore size distributions of HP-β-CD, CD-pMOFI, and CD-pMOFII were determined by nitrogen adsorption method. As Figure 7 (D) shows, the specific surface area of CD-pMOF is significantly increased compared with that of HP-β-CD. As Figure 7 (E) shows, HP-β-CD contains a small amount of micropores, which correspond to the inherent cavities of its molecular structure; while CD-pMOF has both micropores and mesopores, and its micropores are derived from the inherent structural characteristics of HP-β-CD. CD-pMOF I and CD-pMOF II show two different pore size peaks at 2.65 nm, 3.46 nm and 2.65 nm, 3.33 nm respectively, which are new nano-mesopores formed by the coordination of HP-β-CD molecules and Na + . The dual presence of micropores (less than 2 nm) and mesopores (2 - 50 nm) reflects the hierarchical pore network in CD-pMOF, which is crucial for applications that benefit from increased specific surface area and adjustable pore size, especially in drug loading.

[0110] The small-angle X-ray scattering technique was used to measure HP-β-CD, CD-pMOFI, and CD-pMOFII, and the scattering vector (q) ranged from 0.115 to 2.360 nm. -1 , and the pore size was calculated according to the formula d = 2π / q. As Figure 7 (F) shows, compared with HP-β-CD, CD-pMOF exhibits significantly different small-angle scattering curves, especially in the high-q value region, which reflects the significantly different small pore structures of CD-pMOF and HP-β-CD. These changes indicate that the coordination between HP-β-CD and Na + introduces new channels inside CD-pMOF, thus changing the pore connectivity.

[0111] 2. Study on the coordination mechanism of CD-pMOF

[0112] CD-pMOF was prepared with HP-β-CD (substitution degree of 4.71) and NaAc at different molar ratios (0.5:1, 1:1, 1:2, 1:4, 1:6, 1:8) (according to the method for preparing NaAc-CD-pMOF I in Example 1). The content of HP-β-CD in CD-pMOF was determined by high performance liquid chromatography-evaporative light scattering detection (HPLC-ELSD). After deducting the water and residual organic solvents introduced during the preparation process, the molar ratio of HP-β-CD to NaAc in CD-pMOF was calculated based on the average molecular weight of HP-β-CD. Liquid chromatography conditions: the mobile phase was methanol-water (volume ratio of 90:10), the flow rate was 1.0 mL / min, the column temperature was 25 °C, the detector was an evaporative light scattering detector, the drift tube temperature was 50 °C, the gain was 5, and the injection volume was 5 μL. As Figure 8 (A) shows, the molar ratio of HP-β-CD to NaAc in CD-pMOF is stably maintained at 1.32:1, with a relatively fixed stoichiometric relationship, and does not show a positive correlation with the increase in the feeding molar ratio. This indicates that HP-β-CD can coordinate with Na + to form a multi-substituted cyclodextrin supramolecular material.

[0113] CD-pMOF was prepared with HP-β-CD with different substitution degrees (4.56, 4.71, 5.55, 5.59, 6.19) and NaAc at a feeding molar ratio of 1:2 (according to the method of Example 1). The content of HP-β-CD was determined according to the above HPLC-ELSD detection method, and the molar ratio of HP-β-CD to NaAc in CD-pMOF was calculated based on the average molecular weight of HP-β-CD with each substitution degree. As Figure 8As shown in (B), the molar ratio of HP-β-CD to NaAc in CD-pMOF decreases with the increase of the substitution degree of HP-β-CD, indicating that the number of hydroxypropyl substitutions affects the coordination ability of HP-β-CD. The greater the substitution degree, the fewer the number of binding sites available for coordination on the HP-β-CD molecule, resulting in a change in the binding mode between HP-β-CD and Na + Ac. As a multi-substituted cyclodextrin, HP-β-CD has hydroxypropyl groups substituting the hydrogen atoms of the hydroxyl groups at positions C2, C3, and C6 of β-cyclodextrin. As shown in Figure 9 (A), when the hydroxypropyl substitution site is C2-OH, the C6-OH on this glucosyl unit has the ability to coordinate with Na + Ac. However, due to steric hindrance and the influence of the connected ring structure, the oxygen atom at the C2 position is difficult to coordinate with Na + Ac together with the -OH on C3-OH or the hydroxypropyl group. When the substitution site is C3, as shown in Figure 9 (B), the coordination mode is the same. Therefore, when the substitution site is at C2 or C3, only one coordination binding mode can be observed within the glucosyl unit of HP-β-CD. As shown in Figure 9 (C), when the substitution site is C6, there are three -OCCO- motifs with the ability to coordinate with Na + Ac within the glucosyl unit, including C2 and C3-OH, the oxygen atom at the C6 position and the oxygen atom of the glycoside ring, and the oxygen atom at the C6 position and the -OH on the hydroxypropyl group. Therefore, there are three ligand binding modes. Under the mild preparation conditions of HP-β-CD, hydroxypropyl will preferentially substitute the hydrogen atoms of C2 and C3-OH on β-cyclodextrin. In this case, the greater the substitution degree, the more C2 or C3-OH are substituted, and the fewer the coordination sites available for binding with Na + Ac in HP-β-CD, resulting in a smaller molar ratio of HP-β-CD to Na + Ac in the formed CD-pMOF.

[0114] In the CD-MOF with Na + Ac as the metal node, affected by steric hindrance, Na + is usually connected to at most 4 cyclodextrins and mainly shows two coordination modes: hexacoordination and dicoordination. Generally speaking, when the coordination molar ratio of CD to Na + Ac is 1:1, Na + is connected to the cyclodextrin in a hexacoordination mode. If the coordination molar ratio is 1:2, both the hexacoordination and dicoordination modes will exist simultaneously. In the multi-substituted cyclodextrin supramolecular material based on HP-β-CD, the coordination molar ratio of HP-β-CD to Na + Ac is between 1:1 and 1:2. Therefore, Na +It is very likely that both six - coordination (Na1) and two - coordination (Na2) modes are presented simultaneously, as Figure 10 shown. In this case, Na + coordinates with 4 HP - β - CD to form a six - coordination mode, involving C6 - OH and the oxygen atoms of adjacent glycoside rings, C2 and C3 - OH, as well as the - OH on two hydroxypropyl groups. The two - coordination mode is formed by coordinating with the - OH on the hydroxypropyl groups of two HP - β - CD respectively.

[0115] 3. Hypothesis of the supramolecular structural unit of CD - pMOF

[0116] In order to visually present the stacking mode of CD - pMOF, a hypothesis of its supramolecular structural unit is proposed. CD - pMOF has different pore - size peaks from HP - β - CD, which indicates that CD - pMOF forms a new type of nano - mesopore. It is speculated that these nano - mesopores have a spherical structure, and HP - β - CD molecules occupy the surface of the spherical pores, forming supramolecular spherical cavities with diameters of 2.65 nm and 3.40 nm respectively. According to the diameters of these spherical cavities and the secondary - face diameter of HP - β - CD molecules (1.54 ± 0.04 nm), the surface areas of these two spherical pores are calculated to be approximately 21.9 nm 2 and 36.2 nm 2 , while the surface area of the secondary - face of HP - β - CD is 1.8 - 2.0 nm 2 . In addition, considering the molar ratio of HP - β - CD to Na + in CD - pMOF is 1:1.32, it is estimated that on the surface of the spherical cavity with a diameter of 2.65 nm, there are approximately 12 HP - β - CD molecules and 14 Na + ; on the surface of the spherical cavity with a diameter of 3.40 nm, there are approximately 18 HP - β - CD molecules and 24 Na + , as Figure 11 shown. Therefore, by means of molecular modeling, randomly combine three different substitution - type HP - β - CD molecules, and according to the obtained quantity ratio, a CD - pMOF supramolecular structural unit with two types of spherical cavities (2.65 nm and 3.40 nm) is proposed.

[0117] Example 7

[0118] 1. Loading eugenol by gas - solid method

[0119] Accurately weigh 20 mg of eugenol (Eug) and 380 mg of CD-pMOF (NaAc-CD-pMOF I and NaAc-CD-pMOF II prepared in Example 1) into a gas-phase vial, seal it, and vortex mix. Then place it in a forced-air drying oven at 90 °C. During this period, take it out every 10 min, vortex mix for 1 min, repeat 6 times, seal and store it after cooling to obtain Eug@CD-pMOF I and Eug@CD-pMOF II. And prepare Eug@HP-β-CD by the same method. Determine the content of Eug by high-performance liquid chromatography. The liquid chromatography conditions are as follows: mobile phase methanol-water-acetonitrile (volume ratio 31:31:38), flow rate 1.0 mL / min, detection wavelength 280 nm, column temperature 35 °C, detector ultraviolet detector, injection volume 5 μL, injection time 5 min. The contents of Eug in Eug@CD-pMOF I, Eug@CD-pMOF II, and Eug@HP-β-CD are 5.00%, 4.77%, and 4.06% respectively.

[0120] 2. Related characterizations of Eug@CD-pMOF

[0121] Observe the morphologies of Eug@CD-pMOF I and Eug@CD-pMOF II using a scanning electron microscope. As Figure 12 shown, Eug@CD-pMOF maintains the spherical morphology of CD-pMOF, and the drug-loading process does not change the morphology of the original CD-pMOF particles.

[0122] Determine the particle size distribution of the drug-loaded microparticles using a dry laser particle size analyzer. As Figure 13 (A) shows, although the particle sizes D 50 of Eug@CD-pMOF I and Eug@CD-pMOF II increase to 3.71 μm and 6.78 μm respectively, they still meet the inhalation particle size requirements.

[0123] Measure the infrared absorption spectra and Raman absorption spectra of Eug, CD-pMOF I, CD-pMOF II, Eug@CD-pMOF I, and Eug@CD-pMOF II using FTIR and a laser micro-Raman imager. As Figure 13 (B) shows, Eug shows an infrared absorption peak at 1514 cm -1 . As Figure 13 (C) shows, Eug shows a Raman absorption peak at 1643 cm -1 , corresponding to the benzene ring skeletal vibration and C═C stretching vibration respectively. In Eug@CD-pMOF, these characteristic absorption peaks disappear or weaken, thus confirming that Eug is successfully loaded into CD-pMOF.

[0124] 3. High-temperature stability evaluation and drug-loading mechanism research

[0125] Accurately weigh 10 mg of Eug, Eug@CD-pMOF I, Eug@CD-pMOF II, and Eug@HP-β-CD into 10 mL centrifuge tubes respectively, place them open in an environment at 60 °C, and sample at 0, 2, 4, 8, 12, and 24 h. Add 2 mL of methanol-water-acetonitrile (volume ratio 31:31:38) for dissolution, and determine the content of Eug by high performance liquid chromatography. As Figure 13 (D) shows, under the condition of 60 °C, the residual amount of Eug after 24 h is 27.74%, and the remaining content of Eug in Eug@HP-β-CD is 48.23%, which indicates that HP-β-CD has a limited effect on improving the thermal stability of Eug. While the residual amounts of Eug in Eug@CD-pMOF I and Eug@CD-pMOF II are 95.87% and 96.96% respectively, which indicates that CD-pMOF can effectively solidify Eug, significantly improve the thermal stability of Eug and reduce its volatility. This shows that in Eug@CD-pMOF, Eug is not only encapsulated by the traditional cavity structure of HP-β-CD, but is effectively protected in the new nano-spherical pores of CD-pMOF, which emphasizes the superiority of the multi-substituted cyclodextrin supramolecular material in structure and function, and further reveals the possible existence state of eugenol in the CD-pMOF supramolecular structure. It is speculated that Eug exists in the structural unit of CD-pMOF in the form of nano-clusters. According to the 5% Eug loading in Eug@CD-pMOF, the molar ratio of HP-β-CD, Na + and Eug is calculated to be 1:1.32:0.462. As Figure 14 shown, it is calculated that the cavity with a diameter of 2.65 nm in CD-pMOF can encapsulate 5 Eug molecules, and the cavity with a diameter of 3.40 nm can accommodate 8 Eug molecules. These nano-clusters are effectively encapsulated by the spherical structure formed by the coordination of HP-β-CD and Na + , providing a basis for the controlled release of drugs. During the release process of Eug, it must pass through the HP-β-CD molecular channels in CD-pMOF layer by layer, and these molecular channels play the role of a "curtain wall", restricting the evaporation rate of Eug, thus realizing controlled release. This mechanism ensures the stability of Eug and significantly reduces its volatility. Therefore, compared with HP-β-CD, the supramolecular structure of CD-pMOF shows better performance in improving drug stability and delivery.

[0126] 4. Aerodynamic evaluation

[0127] Determined according to the method for measuring the evacuation rate in the 2020 edition of the Chinese Pharmacopoeia. Take the second-generation HPMC capsules, accurately weigh them, and record the mass of the empty capsule shell as W1. Each capsule is filled with 20 mg of CD-pMOF (prepared in Example 1) and Eug@CD-pMOF respectively. The mass of the capsule filled with the carrier powder is W2. Place it in the inhalation device for the NGI experiment. Set the flow rate to 60 L / min. After the operation ends, record the total mass of the capsule and the remaining drug as W3, and calculate the evacuation rate. The formula is as follows:

[0128]

[0129] The results showed that at a volume flow rate of 60 L / min, the capsule evacuation rates of CD-pMOF I, CD-pMOF II, Eug@CD-pMOF I, and Eug@CD-pMOF II were 96.21%, 95.8%, 95.65%, and 96.66% respectively, meeting the evacuation rate requirements (greater than 90%) of inhalation preparations.

[0130] Accurately weigh 20 mg of the sample to be tested and fill it into the second-generation HPMC capsules. There are 5 capsules in each group, and a total of three groups. Coat each collection plate of the NGI with a 1% silicone oil n-hexane solution to avoid particle bounce and inaccurate test results. Load 15 mL of methanol-water (volume ratio 90:10) or methanol-water-acetonitrile (volume ratio 31:31:38) into the pre-separator of the NGI. After assembling the NGI as required, connect the two-way magnetic flux valve and the vacuum pump in sequence, and set the pumping time T (4 s) on the two-way magnetic flux valve. Place the filled capsules into the inhalation device, pierce the capsules, tightly connect the inhalation device with the adapter and the NGI, press the start button to start the inhalation test, and remove the inhalation device after 10 s. Repeat the test for 5 capsules. After the test, the CD-pMOF group uses methanol-water (volume ratio 90:10) to clean the inhalation device, adapter, larynx, pre-separator, collection plates Stage-1 to Stage-7, and the MOC plate, and transfer the washing solutions to volumetric flasks respectively. Determine the content according to "HPLC-ELSD"; Eug@CD-pMOF uses methanol-water-acetonitrile (volume ratio 31:31:38) to clean the inhalation device, adapter, artificial larynx, pre-separator, collection plates Stage-1 to Stage-7, and the MOC plate, and transfer the washing solutions to volumetric flasks respectively. Determine the content of Eug according to the aforementioned liquid chromatography conditions, and calculate the deposition ratio of the sample to be tested at each stage. As Figure 15 shown, the percentages of fine particles of CD-pMOF I and Eug@CD-pMOF I were 64.1% and 65.05% respectively, showing excellent in vitro pulmonary deposition effects and meeting the requirements of the pulmonary deposition rate of dry powder inhalants. As Figure 16As shown, CD-pMOF II and Eug@CD-pMOF II were mainly deposited in the upper respiratory tract, with deposition percentages of 73.8% and 82.19% respectively, showing strong targeting in upper respiratory tract drug delivery. Therefore, as a new drug delivery carrier, CD-pMOF can be selectively deposited in the respiratory tract, having great potential in inhalation therapy and making it an ideal carrier for future respiratory tract treatment.

[0131] 5. Safety evaluation

[0132] The irritation study of Eug@CD-pMOF in rats was carried out to evaluate its inhalation safety.

[0133] Eug@CD-pMOF II was sprayed on the throats of rats at a dose of 200 mg / kg. At the same time, Eug@CD-pMOF I was delivered to the lungs of rats at a dose of 40 mg / kg with the help of a DP-4 dry powder inhaler. The drug was administered once a day for 7 consecutive days. After administration, all rats were fasted and water-deprived for 30 min. On the 7th day, the rats were euthanized 12 h after administration. The throat and lung tissues were collected, fixed in neutral paraformaldehyde for 24 h, and histological analysis was performed using hematoxylin-eosin (HE) staining. As Figure 17 shown, the staining results of tissue sections showed that the surface layer of the throat tissue of the control group rats was covered with non-keratinized stratified epithelial cells, and the basal layer and submucosa were normal. After the administration of Eug@CD-pMOF II to the throat, there was no obvious difference from the control group, and no irritating reaction was observed. The alveolar structure of the administration group was normal, and no inflammatory cells were found. The results showed that CD-pMOF had good safety and no irritation in upper respiratory tract and lung drug delivery, laying a foundation for its application in the treatment of respiratory-related diseases and drug delivery fields.

[0134] Example 8

[0135] 1. Loading iodine by gas-solid method

[0136] Precisely weigh 10 mg of iodine (I2) and 990 mg of CD-pMOF II (NaI-CD-pMOF II prepared with NaI as the metal salt in Example 3) into a 50 mL centrifuge tube, seal it, and manually mix for 1 min. Place the centrifuge tube in a forced-air drying oven at 60 °C. During this period, take it out every 10 min, manually shake and mix for 1 min, repeat 6 times, and store it sealed after cooling to obtain I2@CD-pMOF II.

[0137] 2. Characterization of I2@CD-pMOF

[0138] The particle size distribution of the drug-loaded microparticles was measured using a dry laser particle size analyzer. As Figure 18 shown, there was no obvious change in the particle size before and after iodine loading, and it still met the inhalation particle size requirements.

[0139] The infrared spectra of I2, HP-β-CD, CD-pMOF II, and I2@CD-pMOF II were measured using an FTIR instrument. As Figure 19 (A) shows, the characteristic peak at 1400.6 cm -1 belongs to I2, and this characteristic peak disappears in I2@CD-pMOF II, indicating that I2 is loaded onto CD-pMOF II.

[0140] A laser micro-Raman imager was used to analyze CD-pMOF II and I2@CD-pMOF II. As Figure 19 (B) shows, a new peak appears at around 107 cm in I2@CD-pMOF II. This peak belongs to the characteristic peak of I3 -1 , indicating that there is a charge transfer of I2 in the carrier, and further proving that the mechanism of iodine loading lies in that I - can form I3 with I2 - , and I3 - is relatively stable and can be stably loaded. -

[0141] 3. High-temperature and high-humidity stability evaluation

[0142] Iodine has poor stability to temperature and humidity, and such poor stability is not conducive to its use, storage, and transportation. Referring to the guiding principles for stability tests of raw drugs and preparations in the Chinese Pharmacopoeia (2020 Edition, Volume IV), the high-temperature (60 °C) and high-humidity (25 °C, RH 75%) conditions in the stress testing were set to evaluate the stability of I2@CD-pMOF II. After accurately weighing an appropriate amount of the sample with the same iodine content, it was laid flat in a vial or weighing bottle and placed in an open state in a constant-temperature drying oven at 60 °C and a stability test chamber at 25 °C and RH 75%. Samples were taken out at 0, 5, and 10 days, and the remaining iodine content in the samples was determined by potentiometric titration. The determination method was as follows: Prepare a 1.005 mmol / L NaS2O3 standard titrant and a 0.05 mol / L KI solution. Take I2@CD-pMOF and place it in a titration cup, add 80 mL of 0.05 mol / L KI solution, dissolve it by ultrasonic treatment, and then perform potentiometric titration. Record the volume of the titrant consumed to reach the titration end point. Calculate the iodine content according to the following formula:

[0143]

[0144] is the volume of the titrant consumed during the titration process, is the concentration of the titrant, 254 is the relative molecular mass of I2, and N is the weighed amount of I2@NaI-HP-β-CD.

[0145] As Figure 20As shown in the figure, under the constant temperature and humidity conditions of 60 °C and 25 °C, 75% RH, the iodine content of I2@CD-pMOF did not change significantly within ten days, maintaining good stability, which proves that the carrier CD-pMOF is of great help in improving the stability of iodine.

[0146] 4. In vitro deposition distribution

[0147] Take the second-generation HPMC capsules, weigh them precisely, and record the mass of the empty capsule shell as W1. Then, fill each capsule with 20 mg of CD-pMOF II and I2@CD-pMOF II respectively. The mass of the capsule filled with the carrier powder is W2. Place it in the inhalation device for the NGI experiment. Set the flow rate to 60 L / min. After the operation, record the total mass of the capsule and the residual drug W3, and calculate the evacuation rate. The formula is as follows:

[0148]

[0149] The results show that at a volume flow rate of 60 L / min, the evacuation rates of the capsules of CD-pMOF II and I2@CD-pMOF II are about 95%, both greater than 90%, meeting the requirements of inhalation administration.

[0150] Precisely weigh 20 mg of the sample to be tested and fill it into the second-generation HPMC capsules. There are 5 capsules in each group, and a total of three groups. Coat each collection plate of the NGI with a 1% silicone oil n-hexane solution to avoid particle bounce and inaccurate test results. Load 15 mL of methanol-water (volume ratio 90:10) or 0.05 mol / L KI solution into the pre-separator of the NGI. After assembling the NGI as required, connect the two-way magnetic flux valve and the vacuum pump in sequence, and set the pumping time T (4 s) on the two-way magnetic flux valve. Place the filled capsule into the inhalation device, pierce the capsule, tightly connect the inhalation device with the adapter and the NGI, press the start button to start the inhalation test. After 10 s, remove the inhalation device, and repeat the test for 15 capsules. After the test, the CD-pMOF II group uses methanol-water (volume ratio 90:10) to clean the inhalation device, adapter, artificial larynx, pre-separator, MOC plate, and collection plates Stage-1 to Stage-7, and uses HPLC-ELSD for content determination; while the I2@CD-pMOF II group uses 80 ml of KI solution to clean the inhalation device, adapter, artificial larynx, pre-separator, MOC plate, and collection plates Stage-1 to Stage-7, transfer it to the titration cup, and use potentiometric titration to determine the iodine content. As Figure 21As shown, CD-pMOF II and I2@CD-pMOF II were mainly deposited in the upper respiratory tract, with deposition percentages of 79.36% and 85.61% respectively. This indicates that CD-pMOF II has good upper respiratory tract targeted delivery ability as a drug carrier, and the delivery efficiency is higher after loading iodine, which is beneficial for local drug delivery in the upper respiratory tract.

[0151] 5. Antibacterial efficacy evaluation

[0152] To evaluate the antibacterial efficacy of I2@CD-pMOF II, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of I2 and I2@CD-pMOF II against E.coil and S.aureus were determined. 500 μg / mL I2 and I2@CD-pMOF II solutions prepared with 0.25 mol / L NaI solution were respectively added to sterile 96-well plates, and serially diluted in half with the same concentration of NaI solution. Then, 100 μL of bacterial suspension was added to each well, and each sample was repeated in 3 rows. After culturing at 37 °C for 24 h, the lowest concentration at which the medium was not turbid was visually observed as the MIC value. According to the MIC value, 50 μL of solution was taken from each well with the lowest inhibitory concentration and the wells where no turbidity was visually observed, and 50 μL of LB liquid medium was added and mixed. After mixing evenly, 50 μL was taken from it for plating, and cultured at 37 °C for 12 h. The concentration in the well with no bacterial growth was used as the MBC value of the sample against the bacterium, as shown in Table 1. The results showed that the antibacterial effect of I2@CD-pMOF II was better than that of I2, which might be due to the enhanced inhibition of I2 itself against the two bacteria after the stable binding of I2 and CD-pMOF II.

[0153] Table 1 Antibacterial efficacy evaluation of I2 and I2@CD-pMOF II

[0154]

[0155] 6. Hemolysis safety evaluation

[0156] To evaluate the in vitro safety of CD-pMOF II, its hemolytic property was determined. A negative control group was prepared by adding 0.4 mL of normal saline to 0.4 mL of rabbit red blood cell suspension; a positive control group was prepared by adding 0.4 mL of water to 0.4 mL of rabbit red blood cell suspension; the test sample solution was diluted with 0.9% sodium chloride to prepare test sample solutions at different concentrations, and 0.4 mL of each was taken and added to 0.4 mL of rabbit red blood cell suspension as the sample group. The solutions of each group were gently shaken and mixed evenly, and incubated in a water bath at 37 °C for 3 h. After taking out from the water bath, the hemolytic phenomenon was observed, and the absorbance (A) was measured at a wavelength of 545 nm to plot the hemolysis rate-concentration curve of each sample. The hemolysis rate was calculated according to the following formula:

[0157]

[0158] As Figure 22 shown, the hemolysis rate of CD-pMOF II showed concentration dependence and maintained a low hemolysis rate within a relatively large concentration range, indicating that CD-pMOF II has good safety.

[0159] Example 9

[0160] 1. Loading eucalyptol by gas-solid method

[0161] Weigh accurately 20 mg of eucalyptol, D-limonene and α-pinene respectively, and place them in a gas-phase vial together with 380 mg of CD-pMOF II (NaAc-CD-pMOF II prepared in Example 1), seal the vial, and vortex mix. Place it in a forced-air drying oven at 90 °C, take it out every 10 min during this period, vortex mix for 1 min, repeat 6 times, and store it sealed after cooling to obtain eucalyptol@CD-pMOF II, D-limonene@CD-pMOF II and α-pinene@CD-pMOF II. The contents of eucalyptol, D-limonene and α-pinene were determined by high performance liquid chromatography respectively. The liquid chromatography conditions were as follows: the mobile phase was acetonitrile-water (volume ratio 70:30), the flow rate was 1.0 mL / min, the detection wavelength was 203 nm, the column temperature was 35 °C, the detector was an ultraviolet detector, and the injection volume was 20 μL. The contents of eucalyptol, D-limonene and α-pinene in eucalyptol@CD-pMOF II, D-limonene@CD-pMOF II and α-pinene@CD-pMOF II were 4.65%, 4.67% and 4.72% respectively.

[0162] 2. Loading paeonol by gas-solid method

[0163] Accurately weigh 20 mg of paeonol (PAE) and 380 mg of CD-pMOF II (NaAc-CD-pMOF II prepared in Example 1) into a gas-phase vial, seal it, and vortex mix. Place it in a forced-air drying oven at 90 °C. During this period, take it out every 10 min, vortex mix for 1 min, repeat 6 times, seal and store it after cooling to obtain PAE@CD-pMOF II. Determine the content of PAE by high-performance liquid chromatography. The liquid chromatography conditions are as follows: the mobile phase is methanol-water (volume ratio 45:55), the flow rate is 0.8 mL / min, the detection wavelength is 274 nm, the column temperature is 25 °C, the detector is an ultraviolet detector, and the injection volume is 10 μL. The content of PAE in PAE@CD-pMOF II is 4.82%.

[0164] 3. Loading of L-menthol by gas-solid method

[0165] Accurately weigh 20 mg of L-menthol and 380 mg of CD-pMOF II (NaAc-CD-pMOF II prepared in Example 1) into a gas-phase vial, seal it, and vortex mix. Place it in a forced-air drying oven at 70 °C. During this period, take it out every 10 min, vortex mix for 1 min, repeat 6 times, seal and store it after cooling to obtain L-menthol@CD-pMOF II. Determine the content of L-menthol by gas chromatography. The gas chromatography conditions are as follows: the flow rate is 1.0 mL / min, the injection volume is 1 μL, and the split ratio is 5:1; the inlet temperature is 250 °C, the detector temperature is 260 °C, and the programmed temperature rise (initial temperature, 80 °C, hold for 1 min, rise to 250 °C at 30 °C / min, hold for 2 min). The content of PAE in L-menthol@CD-pMOF II is 4.85%.

[0166] 4. Loading of dexamethasone by incubation method

[0167] Weigh 20 mg of dexamethasone (DEX) and dissolve it in 40 mL of acetone. Ultrasonic for 5 min, filter, add 380 mg of CD-pMOF II (NaAc-CD-pMOF II prepared in Example 1), and react at a temperature of 40 °C and a stirring speed of 200 rpm for 3 h. Centrifuge at a speed of 4000 rpm for 5 min, discard the supernatant, add an appropriate amount of 10 mL of acetone to wash away the free drug, and dry the precipitate in a vacuum drying oven at 40 °C for 12 h to obtain DEX@CD-pMOF II. Determine the content of DEX by HPLC-MS / MS. The liquid chromatography conditions are as follows: the mobile phase is acetonitrile-0.1% formic acid aqueous solution (volume ratio 30:70), the flow rate is 0.5 mL / min, the column temperature is 35 °C, and the ion source is ESI +, the detection mode was MRM, the ion pair was m / z 393.2→373, and the injection volume was 10 μL. The content of DEX in DEX@CD-pMOF II was measured to be 2.02%.

[0168] 5. Loading budesonide by incubation method

[0169] Weigh 20 mg of budesonide (BUD) and dissolve it in 50 mL of acetone. Sonicate for 5 min, filter, add 380 mg of CD-pMOF II (NaAc-CD-pMOF II prepared in Example 1), and react at 40 °C with a stirring speed of 200 rpm for 3 h. Centrifuge at 4000 rpm for 5 min, discard the supernatant, add an appropriate amount of 10 mL of acetone to wash away the free drug, and dry the precipitate in a vacuum drying oven at 40 °C for 12 h to obtain BUD@CD-pMOF II. The content of BUD was determined by HPLC-MS / MS. The liquid chromatography conditions were as follows: the mobile phase was acetonitrile-5 mM ammonium acetate aqueous solution (volume ratio 80:20), the flow rate was 0.7 mL / min, the column temperature was 25 °C, and the ion source was ESI + , the detection mode was MRM, the ion pair was m / z 431.2→413.2, and the injection volume was 5 μL. The content of BUD in BUD@CD-pMOF II was measured to be 2.83%.

[0170] 6. Loading mometasone furoate by incubation method

[0171] Weigh 20 mg of mometasone furoate (MF) and dissolve it in 20 mL of acetone. Sonicate for 5 min, filter, add 380 mg of CD-pMOF II (NaAc-CD-pMOF II prepared in Example 1), and react at 40 °C with a stirring speed of 200 rpm for 3 h. Centrifuge at 4000 rpm for 5 min, discard the supernatant, add an appropriate amount of 10 mL of acetone to wash away the free drug, and dry the precipitate in a vacuum drying oven at 40 °C for 12 h to obtain MF@CD-pMOF II. The content of MF was determined by high performance liquid chromatography. The liquid chromatography conditions were as follows: the mobile phase was methanol-water (volume ratio 75:25, containing 0.2% acetic acid), the flow rate was 1.0 mL / min, the detection wavelength was 254 nm, the column temperature was 40 °C, the detector was an ultraviolet detector, and the injection volume was 20 μL. The content of MF in MF@CD-pMOF II was measured to be 2.62%.

[0172] The foregoing has shown and described the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments, and what is described in the above embodiments and the specification is only to illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A multi-substituted cyclodextrin supramolecular material, characterized in that: The multi-substituted cyclodextrin supramolecular material is obtained by coordinating a multi-substituted cyclodextrin with metal ions.

2. The multi-substituted cyclodextrin supramolecular material according to claim 1, characterized in that: The multi-substituted cyclodextrin is at least one of hydroxypropyl-β-cyclodextrin, sulfobutyl ether-β-cyclodextrin, methylated-β-cyclodextrin, acetylated-β-cyclodextrin, carboxymethyl-β-cyclodextrin, and hydroxyethyl-β-cyclodextrin; Preferably, the degree of substitution of the multi-substituted cyclodextrin is 1 to 21; more preferably, the degree of substitution of the hydroxypropyl-β-cyclodextrin is 2.8 to 10.5; the degree of substitution of the sulfobutyl ether-β-cyclodextrin is 4 to 10; Preferably, the metal ion is Na + , Li + , K + , Rb + , Cs + , Mg 2+ , Ag + , Ca 2+ or at least one of them; Preferably, the coordination molar ratio of the multi-substituted cyclodextrin to the metal ions is 1:(0.5 to 8); Preferably, the multi-substituted cyclodextrin supramolecular material has a spherical morphology; Preferably, the multi-substituted cyclodextrin supramolecular material has an amorphous structure.

3. The preparation method of the multi-substituted cyclodextrin supramolecular material according to claim 1 or 2, characterized in that, It includes the following steps: (1) Dissolve the multi-substituted cyclodextrin and metal ions in a first solvent to obtain a mixed solution; (2) Perform post-treatment, washing, and drying on the mixed solution prepared in step (1) to obtain the multi-substituted cyclodextrin supramolecular material; Preferably, the feeding molar ratio of the multi-substituted cyclodextrin to the metal ions is 1:(0.5 to 10), more preferably 1:(1 to 4); Preferably, the first solvent is at least one of water, methanol, ethanol, propanol, and propylene glycol; Preferably, the concentration of the multi-substituted cyclodextrin in the mixed solution is 0.01 to 0.4 mol / L; the concentration of the metal ions in the mixed solution is 0.02 to 0.8 mol / L; Preferably, the solvent for washing is at least one of isopropanol, acetone, dichloromethane, ethyl acetate, and n-hexane; Preferably, the drying temperature is 50 to 90 °C, more preferably 60 to 70 °C.

4. The preparation method according to claim 3, characterized in that: The method of the post-treatment is one of the hot saturated solution cooling method, anti-solvent addition method, solvent diffusion method, and solvent evaporation method.

5. The preparation method according to claim 4, characterized in that: The hot saturated solution cooling method is to dropwise add a second solvent to the mixed solution under heating conditions until the solution shows white turbidity, and then stop dropping and cool down; Preferably, the second solvent is at least one of isopropanol, acetone, dichloromethane, chloroform, ethyl acetate, n-hexane, and ether; Preferably, the heating temperature is 50 to 90 °C, more preferably 60 to 70 °C; Preferably, the cooling and temperature reduction include two methods of direct cooling and gradient cooling, the cooling temperature is -20 °C to room temperature, more preferably -20 to 4 °C; the cooling time is 0.5 to 8 h, more preferably 2 to 4 h.

6. The preparation method according to claim 4, characterized in that: The anti-solvent addition method is to dropwise add a second solvent to the mixed solution at a certain temperature, and precipitation occurs; Preferably, the second solvent is at least one of isopropanol, acetone, dichloromethane, chloroform, ethyl acetate, n-hexane, and ether. Preferably, the certain temperature is low temperature, room temperature, or heating; more preferably, the low temperature is 0 to 4 °C; the heating temperature is 40 to 60 °C.

7. The preparation method according to claim 4, characterized in that: The solvent diffusion method is to jointly place an open container I containing a mixed solution and an open container II containing a third solvent in a sealed system, and heat the sealed system so that the third solvent in the open container II gradually evaporates and diffuses into the mixed solution in the open container I; Preferably, the third solvent is at least one of acetone, dichloromethane, and ether; Preferably, the heating temperature is 40 to 60 °C.

8. The preparation method according to claim 4, characterized in that: The solvent evaporation method is to place the mixed solution in an open container, add a fourth solvent and then heat it so that the first solvent in the open container gradually evaporates; Preferably, the fourth solvent is at least one of isopropanol, chloroform, ethyl acetate, and n-hexane; Preferably, the heating temperature is 40 to 60 °C.

9. Use of the multi-substituted cyclodextrin supramolecular material according to any one of claims 1 to 2 or the multi-substituted cyclodextrin supramolecular material prepared by the preparation method according to any one of claims 3 to 8 as a drug carrier.

10. A pharmaceutical composition, characterized in that: Comprising the multi-substituted cyclodextrin supramolecular material according to any one of claims 1 to 2 or the multi-substituted cyclodextrin supramolecular material prepared by the preparation method according to any one of claims 3 to 8, and an active ingredient loaded on the multi-substituted cyclodextrin supramolecular material.

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