Crystallization method for improving bulk density and granularity of disodium cytidine monophosphate

Abstract

The invention belongs to the technical field of crystallization, and particularly relates to a crystallization method for improving bulk density and granularity of disodium cytidine monophosphate. The method comprises the following steps: adjusting the pH value of a disodium cytidine monophosphate crude product aqueous solution, cooling, dropwise adding a solvent into the disodium cytidine monophosphate crude product aqueous solution, when the disodium cytidine monophosphate crude product aqueous solution becomes turbid, adding a disodium cytidine monophosphate seed crystal, increasing the pressure in a crystallizer, and growing the crystal; after crystal growing is finished, releasing the pressure, continuously cooling, stirring and crystallizing, and continuously dropwise adding a solvent at the same time; and after the dropwise addition of the solvent is finished, continuously stirring, and finally carrying out solid-liquid separation to obtain the disodium cytidine monophosphate crystal. In the crystallization method of the disodium cytidine monophosphate crystal provided by the invention, modes of pressurized crystal growing and gradient temperature crystallization are introduced in the crystallization process of the disodium cytidine monophosphate, the obtained disodium cytidine monophosphate crystal is high in bulk density, large in crystal particle and good in flowability, and the problems that a later product is easy to agglomerate, non-uniform in loading capacity, overlarge in volume and the like are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of crystallization, and particularly relates to a crystallization method for improving the bulk density and particle size of disodium cytidine. Background Art

[0002] With the development of biotechnology industry and pharmaceutical industry, the research and development of nucleotides and their derivatives has become a hot topic and has gradually formed another major industry after amino acids. Nucleotides are a class of biochemical substances with high added value and are widely used, supporting the development of some large industries, such as high-end dairy industry and pharmaceutical industry. As a functional additive in the dairy industry, its addition can make milk powder closer to breast milk, effectively enhance the ability of infants and young children to resist bacterial dysentery, and reduce the occurrence of diarrhea; in the pharmaceutical field, nucleotides are the raw materials for the production of many nucleotide derivatives as pharmaceutical intermediates, and are used to synthesize hundreds of compounds such as CDP, UDP, GTP, CDP-choline, SAM, cGMP, CTP, UTP, cAMP, UDP-acetylglucosamine, GDP-mannose, GDP-glucose, UDP-glucose, etc. Nucleotide drugs have unique therapeutic effects in anti-cancer, anti-viral, treatment of cardiovascular diseases, diabetes and interference induction, and have good application effects and a huge application market.

[0003] Generally, nucleotide crystallization is carried out by low-temperature alcohol precipitation. This method is prone to heterogeneous nucleation, resulting in impurities being embedded, uneven product size, and poor product quality. Nucleotides with low bulk density cannot ensure uniform loading during the production process, and their packaging volume is large and inconvenient for storage and transportation. Therefore, it is particularly important to find a method for preparing nucleotide crystals with high bulk density and good flow properties. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a crystallization method for improving the bulk density and particle size of disodium cytidylate in view of the problems existing in the crystallization process of disodium cytidylate in the prior art.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0006] The invention discloses a crystallization method for improving the bulk density and particle size of disodium cytidylate. The method comprises the following steps: adjusting the pH value of a disodium cytidylate crude aqueous solution, cooling the solution, dripping a solvent into the disodium cytidylate crude aqueous solution, adding disodium cytidylate seed crystals when the disodium cytidylate crude aqueous solution becomes turbid, and increasing the pressure inside a crystallizer to carry out crystal cultivation; after the crystal cultivation is completed, the pressure is released, the temperature is continuously lowered for stirring crystallization, and the solvent is continuously dripped; after the solvent is dripped, the solution is continuously stirred, and finally solid-liquid separation is performed to obtain disodium cytidylate crystals.

[0007] In some embodiments, preferably, a 15-25 wt% crude disodium cytidylate aqueous solution is adjusted to pH 6.5-7.5 and then added to a crystallizer, cooled to 13-17° C., and a solvent is added dropwise to the crude disodium cytidylate aqueous solution at a flow rate of 8-12% of the crude disodium cytidylate aqueous solution volume / h. When the crude disodium cytidylate aqueous solution becomes turbid, a disodium cytidylate seed crystal is added, and the pressure inside the crystallizer is increased to carry out crystal cultivation; after the crystal cultivation is completed, the pressure is released, the temperature is reduced to 8-12° C., and the mixture is stirred at a speed of less than 100 rpm for stirred crystallization, and the solvent is continued to be added dropwise at a flow rate of 8-12% of the crude disodium cytidylate aqueous solution volume / h until the amount of solvent added reaches 2.0-3.5 times the volume of the crude disodium cytidylate aqueous solution; after the solvent is added dropwise, stirring is continued at 8-12° C. at a speed of less than 100 rpm for 1.5-3.0 h, followed by solid-liquid separation, washing the solid, and drying to obtain disodium cytidylate crystals.

[0008] In some embodiments, it is further preferred that a 20 wt% crude disodium cytidylate aqueous solution is adjusted to pH 7.0 and then added to a crystallizer, cooled to 15°C, and a solvent is added dropwise to the crude disodium cytidylate aqueous solution at a flow rate of 10% of the crude disodium cytidylate aqueous solution volume / h. When the crude disodium cytidylate aqueous solution becomes turbid, a disodium cytidylate seed crystal is added, and the pressure inside the crystallizer is increased to carry out crystal cultivation; after the crystal cultivation is completed, the pressure is released, the temperature is reduced to 10°C, and the mixture is stirred at a speed of less than 100 rpm for stirred crystallization, and the solvent is continued to be added dropwise at a flow rate of 10% of the crude disodium cytidylate aqueous solution volume / h until the amount of solvent added reaches 2.5 times the volume of the crude disodium cytidylate aqueous solution; after the solvent is added dropwise, stirring is continued at 10°C at a speed of less than 100 rpm for 2 hours, followed by solid-liquid separation, washing the solid, and drying to obtain disodium cytidylate crystals.

[0009] In some embodiments, the pH of a 20 wt % aqueous solution of crude disodium cytidylate is adjusted to 7.0, and an alkaline solution is used to adjust the pH to 7.0. The alkaline solution is a conventional alkaline aqueous solution, such as an aqueous sodium carbonate solution, an aqueous sodium bicarbonate solution, or an aqueous sodium hydroxide solution, preferably an aqueous sodium hydroxide solution, more preferably a 25-50 wt % aqueous sodium hydroxide solution, and even more preferably a 30 wt % aqueous sodium hydroxide solution.

[0010] In some embodiments, the solvent is any one of methanol, ethanol, isopropanol and n-butanol, or a combination of several of them.

[0011] In some embodiments, the solvent is ethanol; wherein the solvents are all anhydrous solvents.

[0012] In some embodiments, the mass of the disodium cytidylate seed crystals accounts for 0.5% to 5% of the mass of the crude disodium cytidylate.

[0013] In some embodiments, preferably, the mass of the disodium cytidylate seed crystals accounts for 0.5% to 3% of the mass of the crude disodium cytidylate, more preferably 1% to 2%, and even more preferably 1%.

[0014] In some embodiments, the crystal growing is carried out at 0.01-0.10 MPa.

[0015] In some embodiments, preferably, the crystal growing is carried out at 0.03-0.07 MPa, more preferably 0.04-0.06 MPa, and even more preferably 0.05 MPa.

[0016] In some embodiments, the crystal growing time is 1 to 10 hours.

[0017] In some embodiments, preferably, the crystal growing time is 1 to 6 hours, more preferably 1 to 3 hours, and even more preferably 3 hours.

[0018] In some embodiments, the stirred crystallization is carried out under normal pressure.

[0019] In some embodiments, the drying is vacuum drying, the drying temperature is 30-50° C., and the drying time is 5-15 hours.

[0020] In some embodiments, preferably, the drying is vacuum drying, the drying temperature is 35-45°C, more preferably 40-42°C, and further preferably 40°C; the drying is vacuum drying, the drying time is 5-12h, more preferably 8-12h, and further preferably 10h.

[0021] In some embodiments, the bulk density of the disodium cytidylate crystals is 0.50-0.68 g / mL, and the average particle size is 220-240 μm.

[0022] Beneficial effects:

[0023] In the crystallization method of disodium cytidylate crystals provided by the present invention, a pressurized crystal cultivation and a step temperature crystallization method are introduced in the disodium cytidylate crystallization process, and the obtained disodium cytidylate crystals have high bulk density, large crystal particles, and good fluidity, thereby avoiding the problems of easy agglomeration, uneven loading, and excessive volume of the later product. The method provided by the present invention is simple and easy to operate, and the industrial amplification and conversion are simple, and it is suitable for large-scale industrial application. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, and the above and / or other advantages of the present invention will become more clear.

[0025] Figure 1 : This is a picture of the morphology of the crude disodium cytidylate used in the examples.

[0026] Figure 2 This is a morphology picture of the disodium cytidylate crystal product prepared in Example 1. DETAILED DESCRIPTION

[0027] The present invention can be better understood according to the following examples. However, it is easy for those skilled in the art to understand that the contents described in the examples are only used to illustrate the present invention, and should not and will not limit the present invention described in detail in the claims.

[0028] The experimental methods described in the following examples are conventional methods unless otherwise specified; the reagents and materials described are commercially available unless otherwise specified.

[0029] In the following embodiments, the method for detecting the parameters of the crystal is as follows:

[0030] 1. Crystal bulk density detection method:

[0031] Take a quantity of powder sufficient to complete the test and pass it through a sieve with an aperture greater than 1.0 mm. Place it in a dry, graduated 250 mL measuring cylinder (readable to 2 mL) and gently introduce, without compacting, about 100 grams (m) of the test sample, with an accuracy of 0.1%. Spread the powder carefully, without compression, and read the unit volume (V) to the nearest scale mark when untreated. Bulk density = m / V g / mL.

[0032] 2. Method for detecting average particle size of crystals: detection by particle size distribution instrument.

[0033] 3. The bulk density, particle size, and purity parameters of the crude disodium cytidylate and the disodium cytidylate seed crystals used in the following examples of the present invention are as follows: the bulk density of the crude disodium cytidylate is 0.18 g / mL, the average particle size is 82 μm, and the purity is 96%; the bulk density of the disodium cytidylate seed crystals is 0.60 g / mL, the average particle size is 200 μm, and the purity is 99%. The morphology of the crude disodium cytidylate is shown in the figure below. Figure 1 shown.

[0034] Embodiment 1:

[0035] Take 100g of crude disodium cytidylate, prepare 500mL of aqueous solution with a concentration of 200g / L, stir and dissolve, use 30wt% sodium hydroxide aqueous solution to adjust the pH to 7.0, obtain disodium cytidylate aqueous solution, and place it in a crystallizer; cool the disodium cytidylate aqueous solution crystallization system to 15°C, and add anhydrous ethanol at a rate of 50mL / h; when the disodium cytidylate aqueous solution becomes turbid, add 1g of disodium cytidylate seed crystals, and at the same time, start to increase the internal pressure of the crystallization container to 0.05MPa, and grow crystals at 15°C for 3h. After the growth of crystals, release the pressure, then reduce the temperature of the crystallization system to 10°C, stir and crystallize at normal pressure and a speed of less than 100rpm, and continue to add anhydrous ethanol at a flow rate of 50mL / h, and finally the total volume of anhydrous ethanol added is 1250mL. After the addition of anhydrous ethanol was completed, the mixture was stirred at a speed of less than 100 rpm and 10° C. for 2 h, separated by a centrifuge, the solid was washed with anhydrous ethanol, and vacuum dried at 40° C. for 10 h to obtain disodium cytidine crystals with a bulk density of 0.68 g / mL, an average particle size of 230 μm, and a purity of 99.5%.

[0036] The morphology of the prepared disodium cytidylate crystal product is shown in the figure below: Figure 2 shown.

[0037] Embodiment 2:

[0038] Take 100g of crude disodium cytidylate, prepare 500mL of aqueous solution with a concentration of 200g / L, stir and dissolve, use 30wt% sodium hydroxide aqueous solution to adjust the pH to 7.0, obtain disodium cytidylate aqueous solution, and place it in a crystallizer; cool the disodium cytidylate aqueous solution crystallization system to 15°C, and add anhydrous ethanol at a rate of 50mL / h; when the disodium cytidylate aqueous solution becomes turbid, add 2g of disodium cytidylate seed crystals, and at the same time, start to increase the internal pressure of the crystallization container to 0.05MPa, and grow crystals at 15°C for 2h. After the growth of crystals, release the pressure, then reduce the temperature of the crystallization system to 10°C, stir and crystallize at normal pressure and a speed of less than 100rpm, and continue to add anhydrous ethanol at a flow rate of 50mL / h, and finally the total volume of anhydrous ethanol added is 1250mL. After the addition of anhydrous ethanol was completed, the mixture was stirred at a speed of less than 100 rpm and 10° C. for 2 h, separated by a centrifuge, the solid was washed with anhydrous ethanol, and vacuum dried at 42° C. for 8 h to obtain disodium cytidine crystals with a bulk density of 0.56 g / mL, an average particle size of 220 μm, and a purity of 99.0%.

[0039] Embodiment 3:

[0040] Take 100g of crude disodium cytidylate, prepare 500mL of aqueous solution with a concentration of 200g / L, stir and dissolve, use 30wt% sodium hydroxide aqueous solution to adjust the pH to 7.0, obtain disodium cytidylate aqueous solution, and place it in a crystallizer; cool the disodium cytidylate aqueous solution crystallization system to 15°C, and add anhydrous ethanol at a rate of 50mL / h; when the disodium cytidylate aqueous solution becomes turbid, add 1.5g disodium cytidylate seed crystals, and at the same time, start to increase the internal pressure of the crystallization container to 0.07MPa, and grow crystals at 15°C for 3h. After the growth of crystals, release the pressure, then reduce the temperature of the crystallization system to 10°C, stir and crystallize at normal pressure and a speed of less than 100rpm, and continue to add anhydrous ethanol at a flow rate of 50mL / h, and finally the total volume of anhydrous ethanol added is 1250mL. After the addition of anhydrous ethanol was completed, the mixture was stirred at a speed of less than 100 rpm and 10° C. for 2 h, separated by centrifuge, the solid was washed with anhydrous ethanol, and vacuum dried at 42° C. for 8 h to obtain disodium cytidine crystals with a bulk density of 0.58 g / mL, an average particle size of 225 μm, and a purity of 99.2%.

[0041] Embodiment 4:

[0042] Take 100g of crude disodium cytidylate, prepare 500mL of aqueous solution with a concentration of 200g / L, stir and dissolve, use 30wt% sodium hydroxide aqueous solution to adjust the pH to 7.0, obtain disodium cytidylate aqueous solution, and place it in a crystallizer; cool the disodium cytidylate aqueous solution crystallization system to 15°C, and add anhydrous ethanol at a rate of 50mL / h; when the disodium cytidylate aqueous solution becomes turbid, add 2g of disodium cytidylate seed crystals, and at the same time, start to increase the internal pressure of the crystallization container to 0.03MPa, and grow crystals at 15°C for 1h. After the growth of crystals, release the pressure, then reduce the temperature of the crystallization system to 10°C, stir and crystallize at normal pressure and a speed of less than 100rpm, and continue to add anhydrous ethanol at a flow rate of 50mL / h, and finally the total volume of anhydrous ethanol added is 1250mL. After the addition of anhydrous ethanol was completed, the mixture was stirred at a speed of less than 100 rpm and 10° C. for 2 h, separated by centrifuge, the solid was washed with anhydrous ethanol, and vacuum dried at 42° C. for 8 h to obtain disodium cytidine crystals with a bulk density of 0.56 g / mL, an average particle size of 225 μm, and a purity of 99.3%.

[0043] Comparative Example 1: No tank pressure

[0044] Take 100g of crude disodium cytidylate, prepare 500mL of aqueous solution with a concentration of 200g / L, stir and dissolve, use 30wt% sodium hydroxide aqueous solution to adjust the pH to 7.0, obtain disodium cytidylate aqueous solution, and place it in a crystallizer; cool the disodium cytidylate aqueous solution crystallization system to 15°C, and add anhydrous ethanol at a rate of 50mL / h; when the disodium cytidylate aqueous solution becomes turbid, add 1g of disodium cytidylate seed crystals, and grow crystals at normal pressure and 15°C for 3h. Then, lower the temperature of the crystallization system to 10°C, stir and crystallize at normal pressure and a speed of less than 100rpm, and continue to add anhydrous ethanol at a flow rate of 50mL / h, and finally the total volume of anhydrous ethanol added is 1250mL. After the addition of anhydrous ethanol was completed, the mixture was stirred at a speed of less than 100 rpm and 10° C. for 2 h, and then separated by centrifugation, the solid was washed with anhydrous ethanol, and vacuum dried at 40° C. for 10 h to obtain disodium cytidine crystals with a bulk density of 0.32 g / mL, an average particle size of 122 μm, and a purity of 98.0%

[0045] Comparative Example 2: No Seed

[0046] Take 100g of crude disodium cytidylate, prepare 500mL of aqueous solution with a concentration of 200g / L, stir and dissolve, use 30wt% sodium hydroxide aqueous solution to adjust the pH to 7.0, obtain disodium cytidylate aqueous solution, and place it in a crystallizer; cool the disodium cytidylate aqueous solution crystallization system to 15°C, and add anhydrous ethanol at a rate of 50mL / h; when the disodium cytidylate aqueous solution becomes turbid, increase the internal pressure of the crystallization container to 0.05MPa, and grow crystals at 15°C for 3h. Then, lower the temperature of the crystallization system to 10°C, stir and crystallize at normal pressure and a speed of less than 100rpm, and continue to add anhydrous ethanol at a flow rate of 50mL / h, and finally the total volume of anhydrous ethanol added is 1250mL. After the addition of anhydrous ethanol was completed, the mixture was stirred at a speed of less than 100 rpm and 10° C. for 2 h, separated by centrifuge, the solid was washed with anhydrous ethanol, and vacuum dried at 40° C. for 10 h to obtain disodium cytidine crystals with a bulk density of 0.44 g / mL, an average particle size of 138 μm, and a purity of 98.2%.

[0047] Comparative Example 3: No crystal growth

[0048] 100 g of crude disodium cytidylate was prepared into 500 mL of an aqueous solution with a concentration of 200 g / L, stirred and dissolved, and a 30 wt % sodium hydroxide aqueous solution was used to adjust the pH to 7.0 to obtain an aqueous solution of disodium cytidylate, which was placed in a crystallizer; the crystallization system of the aqueous solution of disodium cytidylate was cooled to 15° C., and anhydrous ethanol was added dropwise at a rate of 50 mL / h; when the aqueous solution of disodium cytidylate became turbid, 1 g of disodium cytidylate seed crystals was added, and then the temperature of the crystallization system was reduced to 10° C., and stirred crystallization was performed at normal pressure and a rotation speed of less than 100 rpm, while anhydrous ethanol was continued to be added dropwise at a flow rate of 50 mL / h, and the total volume of anhydrous ethanol added dropwise was finally 1250 mL. After the addition of anhydrous ethanol was completed, the mixture was stirred at a speed of less than 100 rpm and 10° C. for 2 h, separated by a centrifuge, the solid was washed with anhydrous ethanol, and vacuum dried at 40° C. for 10 h to obtain disodium cytidine crystals with a bulk density of 0.18 g / mL, an average particle size of 92 μm, and a purity of 98.4%.

[0049] The present invention provides a method and idea for improving the bulk density and particle size of disodium cytidine monophosphate crystallization. There are many methods and approaches to implement the technical solution. The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention. All components not specified in this embodiment can be implemented by existing technologies.

Claims

1. A crystallization method for improving the bulk density and particle size of disodium cytidylate, characterized in that: The pH of the crude disodium cytidylate aqueous solution is adjusted and then cooled, and a solvent is added dropwise to the crude disodium cytidylate aqueous solution. When the crude disodium cytidylate aqueous solution becomes turbid, disodium cytidylate seed crystals are added, and the pressure inside the crystallizer is increased to carry out crystal cultivation; after the crystal cultivation is completed, the pressure is released, the temperature is continued to be lowered for stirring crystallization, and the solvent is continued to be added dropwise; after the solvent is added dropwise, stirring is continued, and finally solid-liquid separation is carried out to obtain disodium cytidylate crystals.

2. The crystallization method according to claim 1, characterized in that A 15-25 wt% aqueous solution of crude disodium cytidylate is adjusted to pH 6.5-7.5 and then added to a crystallizer, cooled to 13-17° C., and a solvent is added dropwise to the crude disodium cytidylate aqueous solution at a flow rate of 8-12% of the volume of the crude disodium cytidylate aqueous solution / h. When the crude disodium cytidylate aqueous solution becomes turbid, a disodium cytidylate seed crystal is added, and the pressure inside the crystallizer is increased to carry out crystal cultivation; after the crystal cultivation is completed, the pressure is released, the temperature is reduced to 8-12° C., and the mixture is stirred at a speed of less than 100 rpm for stirred crystallization, and the solvent is continuously added dropwise at a flow rate of 8-12% of the volume of the crude disodium cytidylate aqueous solution / h until the amount of solvent added reaches 2.0-3.5 times the volume of the crude disodium cytidylate aqueous solution; after the solvent is added dropwise, stirring is continued at 8-12° C. at a speed of less than 100 rpm for 1.5-3.0 h, followed by solid-liquid separation, washing the solid, and drying to obtain disodium cytidylate crystals.

3. The crystallization method according to claim 1, characterized in that A 20 wt % aqueous solution of crude disodium cytidylate is adjusted to pH 7.0 and then added to a crystallizer, cooled to 15° C., and a solvent is added dropwise to the crude disodium cytidylate aqueous solution at a flow rate of 10% of the volume of the crude disodium cytidylate aqueous solution / h. When the crude disodium cytidylate aqueous solution becomes turbid, a disodium cytidylate seed crystal is added, and the pressure inside the crystallizer is increased to carry out crystal cultivation; after the crystal cultivation is completed, the pressure is released, the temperature is reduced to 10° C., and the mixture is stirred at a speed of less than 100 rpm for stirred crystallization, and the solvent is continuously added dropwise at a flow rate of 10% of the volume of the crude disodium cytidylate aqueous solution / h until the amount of solvent added reaches 2.5 times the volume of the crude disodium cytidylate aqueous solution; after the solvent is added dropwise, stirring is continued at 10° C. at a speed of less than 100 rpm for 2 hours, followed by solid-liquid separation, washing the solid, and drying to obtain disodium cytidylate crystals.

4. The crystallization method according to any one of claims 1 to 3, characterized in that The solvent is any one of methanol, ethanol, isopropanol and n-butanol or a combination of several of them.

5. The crystallization method according to any one of claims 1 to 3, characterized in that The mass of the disodium cytidylate seed crystals accounts for 0.5% to 5% of the mass of the crude disodium cytidylate.

6. The crystallization method according to any one of claims 1 to 3, characterized in that The crystal growing is carried out at 0.01-0.10 MPa.

7. The crystallization method according to any one of claims 1 to 3, characterized in that The crystal growing time is 1 to 10 hours.

8. The crystallization method according to any one of claims 1 to 3, characterized in that The stirred crystallization is carried out under normal pressure.

9. The crystallization method according to any one of claims 1 to 3, characterized in that The drying is vacuum drying, the drying temperature is 30-50°C, and the drying time is 5-15h.

10. The crystallization method according to any one of claims 1 to 3, characterized in that The bulk density of the disodium cytidylate crystals is 0.50-0.68 g / mL, and the average particle size is 220-240 μm.

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