Metal-organic framework adsorbents, their preparation methods and applications

Abstract

This invention provides a method for preparing a metal-organic framework adsorbent, belonging to the field of adsorbent technology. The invention includes the following steps: dissolving a metal ion salt and an organic ligand in an organic solvent, controlling the reaction temperature and time, centrifuging, washing, and vacuum drying to obtain the metal-organic framework adsorbent; the organic ligand contains one or two of amino, carbonyl, carboxyl, sulfonic acid, and hydroxyl groups; the adsorbent selectively adsorbs glucagon-like peptide-1 analogs. This invention synthesizes a metal-organic framework adsorbent by combining a metal ion salt with an organic ligand containing groups such as amino, carbonyl, carboxyl, sulfonic acid, and hydroxyl groups. It utilizes the charged portion or specific groups in the organic ligand to form hydrogen bonds, ionic bonds, van der Waals forces, and chelation with glucagon-like peptide-1 analog molecules, achieving highly efficient and selective adsorption of glucagon-like peptide-1 analogs, exhibiting high adsorption capacity, fast adsorption rate, and good adsorption stability.

Description

Technical Field

[0001] This invention relates to the field of adsorbent technology, and in particular to a method for preparing a metal-organic framework adsorbent and the application of the metal-organic framework adsorbent prepared by this method in the refinement or separation and enrichment of glucagon-like peptide-1 analogs. Background Technology

[0002] Diabetes and obesity are increasingly prevalent chronic metabolic diseases worldwide, posing significant health risks and economic burdens to individuals and society. There are two types of diabetes: type 1 diabetes, caused by insufficient insulin secretion, and type 2 diabetes, caused by insulin resistance.

[0003] Glucagon-like peptide-1 (GLP-1) analogues are considered the optimal drugs for treating type 2 diabetes and obesity. They work by mimicking and enhancing the effects of the naturally produced GLP-1 hormone, increasing insulin secretion, reducing glucagon release, delaying gastrointestinal emptying, and suppressing appetite and food intake, thereby improving blood sugar control and weight management to achieve therapeutic effects. They have high homology with natural GLP-1. Currently, there are several GLP-1 analogue drugs on the market, such as semaglutide, liraglutide, teduglutide, and exenatide. However, due to the complex separation and purification steps involving column chromatography, high-performance liquid chromatography (HPLC), and gel electrophoresis, the price of GLP-1 analogue drugs remains high. Adsorption methods offer advantages such as high efficiency and selectivity in separation and purification, while being simple and easy to implement, significantly reducing separation and purification costs, thus providing a possibility for low-cost adsorption and enrichment of GLP-1 analogues.

[0004] Metal-organic frameworks (MOFs) have large specific surface area, high pore volume, tunable pore structure design, tunable functional sites, good stability in aqueous solution and high thermal stability, and have good application prospects for peptide separation and enrichment.

[0005] Currently used adsorbent materials for peptide adsorption and enrichment include modified silica gel and modified resins, as illustrated in invention patent CN112516973A. This patent provides a polyamide-amine dendritic macromolecule grafted adsorbent material, using a silica gel matrix as a carrier to graft polyamide-amine dendritic macromolecules. Through interaction with the phosphorylated groups in phosphorylated peptides, it achieves rapid adsorption of phosphorylated peptides in solution. Invention patent CN113457630A provides a magnetic metal-organic framework material MUiO-66-NH2 / PA for the adsorption and enrichment of glycopeptides. However, its synthesis process is complex, and the enrichment process mainly relies on the interaction of hydrophilic groups with the glycosyl groups in glycopeptides, making it unsuitable for non-glycopeptides such as glucagon-like peptide-1 analogs. Modified silica gel, modified resins, and MUiO-66-NH2 / PA adsorbents for peptide adsorption, based on functional modifications such as grafting hydrophilic groups and phosphorylation, exhibit good adsorption performance for some phosphopeptides, glycopeptides, and endogenous peptides. However, they show poor selectivity for homologous peptides (isomers produced by the same synthesis process and with similar physicochemical properties). Furthermore, under mild conditions (room temperature and pressure), the adsorption capacity is low and desorption is difficult. Due to the low synthesis concentration and numerous isomers of glucagon-like peptide-1 analogs, existing adsorbents cannot selectively adsorb and enrich glucagon-like peptide-1 analogs. Additionally, the preparation steps of some modified resins and modified silica gel adsorbents are cumbersome and costly, and the modification process requires the introduction of numerous functional groups, some of which are toxic and unsuitable for drug preparation. Currently, there is no adsorbent for glucagon-like peptide-1 analogs that is simple to synthesize, inexpensive to prepare, exhibits excellent adsorption performance, high selectivity, and is recyclable. MOFs (Metal-Oxide-Factory) materials have tunable pore sizes. Based on target peptide molecules with different kinetic diameters, appropriate organic ligands, metal centers, and structural functionalization modifications can be selected for the selective adsorption of glucagon-like peptide-1 (GLP-1) analogs. GLP-1 analogs are mainly peptides composed of more than twenty amino acids, with kinetic diameters ranging from 3 to 9 nm. By selecting suitable ligands and precisely designing the pore size of MOF materials, larger impurities such as enzymes, carrier proteins, and fusion proteins can be screened out. Furthermore, MOFs are composed of metal ions or metal clusters and organic ligands. The charged portion or specific groups in the organic ligands can bind to GLP-1 analog molecules through hydrogen bonds, ionic bonds, van der Waals forces, and chelation, achieving highly efficient and selective adsorption of GLP-1 analogs. In addition, the organic ligands and metal ions selected during the construction of MOFs can be compounds with good biocompatibility and low toxicity, which can be effectively utilized for the separation and enrichment of GLP-1 analogs. Summary of the Invention

[0006] In view of this, to overcome the shortcomings of the prior art, on the one hand, the present invention provides a method for preparing a metal-organic framework adsorbent capable of selectively adsorbing and enriching glucagon-like peptide-1 analogs. This method involves synthesizing metal-organic framework adsorbents with different pore sizes by reacting metal ion salts with organic ligands having specific groups, such as amino, carbonyl, carboxyl, sulfonic acid, and hydroxyl groups. Simultaneously, the charged portion or specific groups in the organic ligands can bind to glucagon-like peptide-1 analog molecules through hydrogen bonds, ionic bonds, van der Waals forces, and chelation, achieving highly efficient and selective adsorption and enrichment of glucagon-like peptide-1 analogs. This method features high adsorption capacity, fast adsorption rate, good adsorption stability, and the metal-organic framework adsorbent itself is non-toxic and harmless, posing no risk to the drug production process. Furthermore, the preparation process is simple and can be used for mass production.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A method for preparing a metal-organic framework adsorbent includes the following steps:

[0009] Metal ion salts and organic ligands are dissolved in organic solvents at a molar ratio of 1:1-10. The reaction temperature is controlled at 50-200℃ and the reaction time is 12-72h. After centrifugation, washing and vacuum drying, metal-organic framework adsorbents are obtained.

[0010] The organic ligand contains one or two of the following groups: amino, carbonyl, carboxyl, sulfonic acid, and hydroxyl groups.

[0011] The organic ligand is preferably one or two of the following: benzotricarboxylic acid, phthalic acid, imidazole dicarboxylic acid, tris(2-chloropropyl) phosphate, and pyrazine dicarboxylic acid;

[0012] The adsorbent selectively adsorbs glucagon-like peptide-1 analogues.

[0013] Preferably, the metal ion salt is one of a metal nitrate, a metal sulfate, and a metal chloride.

[0014] Preferably, the metal ions in the metal ion salt are selected from one or two of groups IB, IIB, IIIB, IVB, VB, VIB, VIIB or VIIIB in the IUPAC periodic table, or one or two of groups IA, IIA, IIIA, IVA or VIIB.

[0015] Preferably, the metal ion in the metal ion salt is Cu. 2+ Fe 3+ Bi 2+ Al 3+ Cr 3+ and Zr 4+Any one or two of them.

[0016] Preferably, the organic solvent is one or two of N,N-dimethylformamide, methanol, ethanol, ethyl acetate, dimethyl thionamide, and acetone.

[0017] On the other hand, the present invention provides a metal-organic framework adsorbent, which is prepared according to the above-described method for preparing metal-organic framework adsorbents.

[0018] Furthermore, the present invention also provides the application of the above-mentioned metal-organic framework adsorbent in the refinement or separation and enrichment of glucagon-like peptide-1 analogs.

[0019] Preferably, the concentration of the glucagon-like peptide-1 analog is 0.05–50 mg / mL, and the adsorption capacity of the metal-organic framework adsorbent is 0.5–1200 mg / g.

[0020] Preferably, the glucagon-like peptide-1 analogue is a refined or crude product of a GLP-1 receptor agonist and its precursor peptide.

[0021] Preferably, the purity of the glucagon-like peptide-1 analog on the metal-organic framework adsorbent reaches 90-97%.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The method for preparing metal-organic framework adsorbents provided by this invention involves synthesizing metal-organic framework adsorbents with different pore sizes by reacting metal ion salts with organic ligands having specific groups, such as amino, carbonyl, carboxyl, sulfonic acid, and hydroxyl groups. Simultaneously, the charged portion or specific groups in the organic ligands can bind to glucagon-like peptide-1 analog molecules through hydrogen bonding, ionic bonding, van der Waals forces, and chelation, achieving highly efficient and selective adsorption of glucagon-like peptide-1 analogs. This method exhibits high adsorption capacity, fast adsorption rate, and good adsorption stability. Furthermore, the metal-organic framework adsorbent itself is non-toxic and harmless, posing no risk to the drug production process, and can be recycled. The desorption process is simple, significantly reducing the cost of purifying glucagon-like peptide-1 analogs. The preparation process is also simple and suitable for mass production.

[0024] The present invention provides a method for preparing metal-organic framework (MOF) adsorbents and the resulting MOF adsorbents. Compared to existing adsorbents, the MOF adsorbents used in this invention are non-toxic, harmless, have good biological tolerance, and cause minimal environmental pollution. Furthermore, they overcome the shortcomings of existing adsorbents, such as poor selectivity and low adsorption capacity.

[0025] The metal-organic framework (MOF) adsorbent prepared by this invention has a large specific surface area, large pore volume, adjustable pore size (pore diameter of 2-12 nm), and modifiable pore surface. It has a large adsorption capacity and high selectivity, and its adsorption performance can be significantly improved.

[0026] The metal-organic framework (MOF) adsorbent prepared by this invention can be regenerated at a temperature of 25–35°C. The regeneration process requires a low amount of eluent, and the MOF adsorbent can be recycled with stable performance.

[0027] The metal-organic framework adsorbent provided by this invention is used for the refinement or separation and enrichment of glucagon-like peptide-1 analogs. When the concentration of glucagon-like peptide-1 analogs is 0.05-50 mg / mL, the adsorption capacity of the metal-organic framework (MOFs) adsorbent is as high as 0.5-1200 mg / g. After eluting the glucagon-like peptide-1 analogs on the metal-organic framework adsorbent, the purity can reach 90-97%. Detailed Implementation

[0028] To overcome the problems of insufficient biocompatibility, toxicity, low adsorption capacity, slow adsorption rate, difficult desorption, and poor adsorption selectivity of existing adsorbents, this invention aims to expand the research on non-toxic and harmless green metal-organic framework (MOF) adsorbents. This invention provides a method for preparing a metal-organic framework adsorbent, comprising the following steps:

[0029] The metal ion salt and organic ligand are dissolved in an organic solvent at a molar ratio of 1:1-10 (preferably 1:1-4). The reaction temperature is controlled at 50-200℃, and the reaction time is 12-72h. After centrifugation (centrifugation speed can be selected as 6000-12000 rpm), washing (washing solvent can be methanol or DMF, washing can be carried out at room temperature, and the liquid-solid ratio can be selected as 5:1 to 50:1), and vacuum drying (vacuum drying can be selected at 60-90℃ for 8-24h) to obtain the metal-organic framework adsorbent.

[0030] The organic ligand contains one or two of the following groups: amino, carbonyl, carboxyl, sulfonic acid, and hydroxyl groups.

[0031] The organic ligand is preferably one or two of the following: tribenzoic acid, phthalic acid, imidazole dicarboxylic acid, tri(2-chloropropyl) phosphate, and pyrazine dicarboxylic acid; wherein, tribenzoic acid is preferably 1,3,5,-pyromellitic acid, and phthalic acid is preferably terephthalic acid or 2,5-dicarboxy-1,4-phthalic acid.

[0032] The adsorbent selectively adsorbs glucagon-like peptide-1 analogues.

[0033] In this invention, the metal ion salt is one of metal nitrate, metal sulfate, and metal chloride.

[0034] In this invention, the metal ion in the metal ion salt is selected from one or two of groups IB, IIB, IIIB, IVB, VB, VIB, VIIB, or VIIIB in the IUPAC periodic table, or one or two of groups IA, IIA, IIIA, IVA, or VIIB, such as Cu. 2+ Fe 3+ Bi 2+ Al 3+ Cr 3+ and Zr 4+ Any one or two of them.

[0035] In this invention, the organic solvent is one or two of N,N-dimethylformamide, methanol, ethanol, ethyl acetate, dimethyl thionamide, and acetone.

[0036] On the other hand, the present invention provides a metal-organic framework adsorbent, which is prepared according to the above-mentioned method for preparing metal-organic framework adsorbents, wherein the pore size of the metal-organic framework adsorbent is preferably 2-12 nm.

[0037] Furthermore, the present invention also provides the application of the above-mentioned metal-organic framework adsorbent in the refinement or separation and enrichment of glucagon-like peptide-1 analogs.

[0038] In this invention, the concentration of the glucagon-like peptide-1 analog is 0.05–50 mg / mL (preferably 1–3 mg / L), the adsorption capacity of the metal-organic framework adsorbent is 0.5–1200 mg / g, the adsorption temperature is preferably 25–35 °C, and the adsorption time is preferably 30–120 min.

[0039] In this invention, the glucagon-like peptide-1 analogue is a refined or crude product of a GLP-1 receptor agonist and its precursor peptide, wherein the GLP-1 receptor agonist preferably includes liraglutide, semaglutide, tiduglutide, and exenatide.

[0040] In this invention, the purity of the crude glucagon-like peptide-1 analog (GLP-1) and its precursor peptide can be selected as 10-90%. After eluting the glucagon-like peptide-1 analog on the metal-organic framework adsorbent, its purity can reach 90-97%. The eluent can be acetonitrile and water, acetonitrile and buffer, or ethanol and buffer. Preferably, the eluent is acetonitrile and water (60:40, v:v). The desorption temperature is 25-35°C, and the desorption time is 30-60 min.

[0041] The technical solution of the present invention will be clearly and thoroughly described below with reference to specific embodiments.

[0042] Example 1

[0043] Bismuth nitrate pentahydrate and 1,3,5,-pyromellitic acid were dissolved in 50 mL of N,N-dimethylformamide at a molar ratio of 1:1. The mixture was poured into a polytetrafluoroethylene (PTFE) reactor and reacted at 140 °C for 24 h. After centrifugation at 8000 rpm, the mixture was washed with methanol and DMF, and then dried under vacuum at 70 °C to obtain the adsorbent Bi-MOF-1. The pore size distribution of Bi-MOF-1 was calculated using the NLDFT model based on nitrogen adsorption / desorption isotherms, and the pore size of the adsorbent Bi-MOF-1 was found to be 9–11 nm.

[0044] In the adsorption process, Bi-MOF-1 adsorbent was added to the crude semaglutide solution (purity 73.5%, concentration 1 mg / mL) at a solid-liquid ratio of 1 mg / mL, and the solution was placed in a constant temperature shaker at 30℃ for 60 min. After adsorption was complete, the supernatant was collected, and the absorbance at 280 nm was measured using a spectrophotometer. The adsorption amount was determined based on the absorbance values ​​before and after adsorption, and the equilibrium adsorption amount reached 945 mg / g.

[0045] Elution was performed using acetonitrile / water (60:40, v:v) at 25°C. The eluent was freeze-dried (10 mL concentrated to 200 μL) and tested by high performance liquid chromatography (HPLC). The purity of the purified peptide was 97%, indicating that the target peptide and impurity peptides were effectively separated through selective enrichment of the adsorbent.

[0046] Example 2

[0047] Bismuth nitrate pentahydrate and 1,3,5,-pyromellitic acid were dissolved in 50 mL of N,N-dimethylformamide at a molar ratio of 1:10. The mixture was poured into a polytetrafluoroethylene reactor and reacted at 80 °C for 72 h. After centrifugation at 8000 rpm, the mixture was washed with methanol and DMF, and then dried under vacuum at 70 °C to obtain Bi-MOF-2 adsorbent with a pore size of 3-4 nm.

[0048] Bi-MOF-2 was added to the crude semaglutide solution (purity 72.5%, concentration 1 mg / mL) at a solid-liquid ratio of 1 mg / mL and placed in a constant temperature shaker at 30°C for 60 min for adsorption. After adsorption was completed, the adsorption amount and the purity after elution and drying were determined according to the method in Example 1. The equilibrium adsorption amount reached 442 mg / g, and the purity after purification was 90.3%.

[0049] Example 3

[0050] Bismuth nitrate pentahydrate and 1,3,5,-pyromellitic acid were dissolved in 50 mL of N,N-dimethylformamide / methanol (1:1, v:v) at a molar ratio of 1:2. The mixture was poured into a polytetrafluoroethylene reactor and reacted at 140 °C for 48 h. After centrifugation at 8000 rpm, the mixture was washed with methanol and DMF, and then dried under vacuum at 70 °C to obtain Bi-MOF-3 adsorbent with a pore size of 7–9 nm.

[0051] In the adsorption process, Bi-MOF-3 adsorbent was added to the crude semaglutide solution (purity 73.4%, concentration 50 mg / mL) at a solid-liquid ratio of 1 mg / mL and placed in a constant temperature shaker at 37℃ for 30 min for adsorption. After adsorption was completed, the adsorption amount and the purity after elution and drying were determined according to the method in Example 1. The equilibrium adsorption amount reached 1163 mg / g, and the purity after purification was 96.1%.

[0052] Example 4

[0053] Bismuth nitrate pentahydrate and terephthalic acid were dissolved in N,N-dimethylformamide at a molar ratio of 1:2, mixed thoroughly, and poured into a polytetrafluoroethylene reactor. The reaction temperature was 50℃, the reaction time was 72h, and the mixture was centrifuged at 8000rpm. The mixture was washed with methanol and DMF respectively, and then dried under vacuum at 70℃ to obtain Bi-MOF-4 adsorbent. The pore size of Bi-MOF-4 is 4-6nm.

[0054] In the adsorption process, Bi-MOF-4 adsorbent was added to the crude semaglutide solution (purity 71.8%, concentration 0.5 mg / mL) at a solid-liquid ratio of 1 mg / mL and placed in a constant temperature shaker at 30℃ for 60 min for adsorption. After adsorption was completed, the adsorption amount and the purity after elution and drying were determined according to the method in Example 1. The equilibrium adsorption amount reached 375 mg / g, and the purity after purification was 91.6%.

[0055] Example 5

[0056] Bismuth nitrate pentahydrate and imidazole dicarboxylic acid were dissolved in 50 mL of methanol at a molar ratio of 1:2. The mixture was poured into a polytetrafluoroethylene reactor and reacted at 200 °C for 12 h. After centrifugation at 8000 rpm, the mixture was washed with methanol and DMF, and then dried under vacuum at 70 °C to obtain Bi-MOF-5 adsorbent. The pore size of the adsorbent Bi-MOF-5 was calculated to be 2–4 nm using the method described in Example 1.

[0057] In the adsorption process, Bi-MOF-5 adsorbent was added to the crude semaglutide solution (purity 70.2%, concentration 0.1 mg / mL) at a solid-liquid ratio of 1 mg / mL and placed in a constant temperature shaker at 30℃ for 60 min for adsorption. After adsorption was completed, the adsorption amount and the purity after elution and drying were determined according to the method in Example 1. The equilibrium adsorption amount reached 76 mg / g, and the purity after purification was 90.6%.

[0058] Example 6

[0059] Aluminum nitrate and 1,3,5,-pyromellitic acid were dissolved in 50 mL of N,N-dimethylformamide at a molar ratio of 1:2. The mixture was poured into a polytetrafluoroethylene reactor and reacted at 140 °C for 24 h. After centrifugation at 6000 rpm, the mixture was washed with methanol and DMF, and then dried under vacuum at 60 °C to obtain Al-MOF-1 adsorbent. The pore size of Al-MOF-1 is 6–8 nm.

[0060] In the adsorption process, Al-MOF-1 adsorbent was added to the crude semaglutide solution (purity 72.2%, concentration 0.1 mg / mL) at a solid-liquid ratio of 1 mg / mL and placed in a constant temperature shaker at 30℃ for 60 min for adsorption. After adsorption was completed, the adsorption amount and the purity after elution and drying were determined according to the method in Example 1. The equilibrium adsorption amount reached 93 mg / g, and the purity after purification was 91.1%.

[0061] Example 7

[0062] Ferric chloride and 1,3,5,-pyromellitic acid were dissolved in 50 mL of N,N-dimethylformamide at a molar ratio of 1:2. The mixture was poured into a polytetrafluoroethylene reactor and reacted at 140 °C for 24 h. After centrifugation at 6000 rpm, the mixture was washed with methanol and DMF, and then dried under vacuum at 60 °C to obtain Fe-MOF-1 adsorbent. The pore size of Fe-MOF-1 was 2–5 nm. In the adsorption process, Fe-MOF-1 adsorbent was added to a crude semaglutide solution (purity 72.2%, concentration 1 mg / mL) at a solid-liquid ratio of 1 mg / mL and placed in a constant temperature shaker at 30 °C for 60 min. After adsorption, the adsorption capacity and the purity after elution and drying were determined according to the method in Example 1. The equilibrium adsorption capacity reached 47 mg / g, and the purified purity was 93.1%.

[0063] Example 8

[0064] Zirconium chloride and terephthalic acid were dissolved in 50 mL of N,N-dimethylformamide at a molar ratio of 1:1.5, mixed thoroughly, and then placed in a polytetrafluoroethylene reactor. The reaction temperature was 120 °C, and the reaction time was 24 h. After centrifugation at 10,000 rpm, the mixture was washed with methanol and DMF, and then dried under vacuum at 60 °C to obtain Zr-MOF-1 adsorbent. The pore size of Zr-MOF-1 was 7–10 nm. In the adsorption process, Zr-MOF-1 adsorbent was added to a crude liraglutide solution (purity 71.2%, concentration 0.1 mg / mL) at a solid-liquid ratio of 1 mg / mL and placed in a constant temperature shaker at 30 °C for 60 min. After adsorption, the adsorption capacity and the purity after elution and drying were determined according to the method in Example 1. The equilibrium adsorption capacity reached 82 mg / g, and the purified purity was 91.4%.

[0065] Example 9

[0066] Ferric chloride and terephthalic acid were dissolved in 50 mL of N,N-dimethylformamide and methanol (1:1, v:v) at a molar ratio of 1:3. The mixture was poured into a polytetrafluoroethylene reactor and reacted at 180 °C for 12 h. After centrifugation at 8000 rpm, the mixture was washed with methanol and DMF, and then vacuum dried at 60 °C to obtain Fe-MOF-2 adsorbent. The pore size of the adsorbent Fe-MOF-2 was calculated to be 6–9 nm using the method described in Example 1. During the adsorption process, Fe-MOF-2 was added to a crude solution of tedoglutide (purity 81.2%, concentration 0.1 mg / mL) at a solid-liquid ratio of 2 mg / mL and placed in a constant temperature shaker at 35 °C for 60 min. After adsorption, the adsorption capacity and the purity after elution and drying were determined according to the method described in Example 1. The equilibrium adsorption capacity reached 46 mg / g, and the purity after purification was 93.8%.

[0067] Example 10

[0068] Zirconium chloride and 2,5-dicarboxy-1,4-phthalic acid were dissolved in 50 mL of N,N-dimethylformamide at a molar ratio of 1:2. The mixture was poured into a polytetrafluoroethylene reactor and reacted at 160 °C for 24 h. After centrifugation at 8000 rpm, the mixture was washed with methanol and DMF, and then dried under vacuum at 80 °C to obtain Zr-MOF-2 adsorbent. The pore size of Zr-MOF-2 is 7–10 nm. Zr-MOF-2 adsorbent was added to semaglutide solution (concentration 30 mg / mL) at a solid-liquid ratio of 1 mg / mL and placed in a constant temperature shaker at 30 °C for 60 min for adsorption. After adsorption, the equilibrium adsorption capacity reached 946 mg / g.

[0069] Example 11

[0070] Aluminum nitrate and terephthalic acid were dissolved in 50 mL of N,N-dimethylformamide in a molar ratio of 1:1. The mixture was poured into a polytetrafluoroethylene (PTFE) reactor and reacted at 150 °C for 24 h. After centrifugation at 8000 rpm, the mixture was washed with methanol and DMF, and then dried under vacuum at 80 °C to obtain Al-MOF-2 adsorbent. The pore size of Al-MOF-2 was 8–12 nm. In the adsorption process, Al-MOF-2 adsorbent was added to liraglutide solution (concentration 1 mg / mL) at a solid-liquid ratio of 2 mg / mL and placed in a constant temperature shaker at 25 °C for 60 min. After adsorption, the equilibrium adsorption capacity reached 446 mg / g.

[0071] Example 12

[0072] Bismuth nitrate and trimesic acid were dissolved in 50 mL of N,N-dimethylformamide at a molar ratio of 1:2, mixed thoroughly, and poured into a polytetrafluoroethylene reactor. The reaction temperature was 140 °C, and the reaction time was 48 h. After centrifugation at 6000 rpm, the mixture was washed with methanol and DMF, and then dried under vacuum at 70 °C to obtain Bi-MOF-3 adsorbent. In the adsorption process, Bi-MOF-3 adsorbent was added to tiduglutide solution (concentration 50 mg / mL) at a solid-liquid ratio of 10 mg / mL and placed in a constant temperature shaker at 25 °C for 60 min. After adsorption, the equilibrium adsorption capacity reached 115 mg / g.

[0073] Comparative Example 1

[0074] The crude semaglutide solution (purity 73.5%, concentration 1 mg / mL, the crude solution used in Example 1) was purified using an AKTA explorer 100 protein chromatography system. This method is commonly used in peptide separation. An Agilent C18 column (10 mm * 250 mm) was used. The mobile phase A was water and the mobile phase B was acetonitrile. A gradient of 20% to 80% of the mobile phase B was formed over 60 min and maintained for 30 min. The flow rate was 1 mL / min, the temperature was 30 °C, and the injection volume was 1 mL. The main peak was collected based on the real-time chromatogram. Gradient elution of the column was performed before and after purification to form a gradient of 20% to 80% of the mobile phase B over 10 min. The purity of the collected solution was determined using the method in Example 1, and the purity was 92.4%.

[0075] Compared with Comparative Example 1, the purity of the purified samples in Example 1 is approximately equal. The purity of Example 1 after enrichment and elution with the adsorbent is 92.1%, while the purity of Comparative Example 1 is 92.4%. However, the adsorption time of Example 1 is 60 min and the desorption time is 20 min, which is significantly less than the purification time required by the ATKA protein chromatography instrument. Furthermore, the purification process using the ATKA protein chromatography instrument requires approximately 54 mL of acetonitrile and 36 mL of water (excluding the consumption during column rinsing), while Example 1 only consumes approximately 12 mL of acetonitrile and 8 mL of water. Compared with common purification equipment, this invention has advantages in both purification time and solvent consumption while ensuring the purification purity. Chromatographic techniques mainly rely on the adsorption differences between sample molecules and the stationary phase to achieve separation and purification. Taking the C18 column, which is commonly used in peptide separation, as an example, the column is packed with octadecylsilane-bonded silica gel. It has no selectivity for target peptides, fusion proteins, enzymes, and other substances in crude glucagon-like peptide-1 analogues. Separation is required through a relatively sensitive elution gradient. However, the adsorbent developed in this invention can selectively adsorb glucagon-like peptide-1 analogues, thereby significantly reducing the use of organic solvents and purification time while maintaining purification purity.

Claims

1. The application of a metal-organic framework adsorbent in the purification or separation and enrichment of glucagon-like peptide-1 analogs; The preparation method of the metal-organic framework adsorbent includes the following steps: Metal ion salts and organic ligands are dissolved in organic solvents at a molar ratio of 1:1-10. The reaction temperature is controlled at 50-200℃ and the reaction time is 12-72h. After centrifugation, washing and vacuum drying, metal-organic framework adsorbents are obtained. The organic ligand contains one or two of the following groups: amino, carbonyl, carboxyl, sulfonic acid, and hydroxyl groups. The adsorbent selectively adsorbs glucagon-like peptide-1 analogues.

2. The application according to claim 1, characterized in that, The concentration of the glucagon-like peptide-1 analog is 0.05~50 mg / mL, and the adsorption capacity of the metal-organic framework adsorbent is 0.5-1200 mg / g.

3. The application according to claim 1, characterized in that, The glucagon-like peptide-1 analogue is a refined or crude product of a GLP-1 receptor agonist and its precursor peptide.

4. The application according to claim 1, characterized in that, The organic ligand is one or two of the following: benzotricarboxylic acid, phthalic acid, imidazole dicarboxylic acid, tri(2-chloropropyl) phosphate, and pyrazine dicarboxylic acid.

5. The application according to claim 1, characterized in that, After elution of the glucagon-like peptide-1 analog on the metal-organic framework adsorbent, the purity reached 90-97%.

6. The application according to claim 1, characterized in that, The metal ion salt is one of metal nitrate, metal sulfate, and metal chloride.

7. The application according to claim 1, characterized in that, The metal ions in the metal ion salt are selected from one or two of groups IB, IIB, IIIB, IVB, VB, VIB, VIIB or VIIIB in the IUPAC periodic table, or one or two of groups IA, IIA, IIIA, IVA or VIIB.

8. The application according to claim 7, characterized in that, The metal ion in the metal ion salt is Cu. 2+ Fe 3+ Bi 2+ Al 3+ Cr 3+ and Zr 4+ Any one or two of them.

9. The application according to any one of claims 1-8, characterized in that, The organic solvent is one or two of N,N-dimethylformamide, methanol, ethanol, ethyl acetate, dimethyl thionamide, and acetone.