Nanoscale aluminum hydroxide adjuvant as well as preparation method and application thereof

Abstract

The invention relates to the field of aluminum hydroxide adjuvants, in particular to a nanoscale aluminum hydroxide adjuvant as well as a preparation method and application thereof. The preparation method comprises the following steps: by taking aluminum chloride and sodium hydroxide as raw materials, reacting to generate aluminum hydroxide colloid, introducing lauryl sodium sulfate as a colloid stabilizer, further dispersing and granulating the generated aluminum hydroxide colloid at a high speed, aging, concentrating, filtering, sterilizing and the like, thereby obtaining the aluminum hydroxide colloid. The problems that the aluminum hydroxide colloid is poor in aggregation and dispersity and the like are solved, the aluminum hydroxide colloid reaches the nanoscale, the problem that the aluminum hydroxide colloid cannot be sterilized through filtration in the prior art is solved, and finally the nanoscale aluminum hydroxide colloid with good distribution uniformity and low PDI value is obtained. The problems that in the prior art, the particle size of the aluminum hydroxide adjuvant cannot be accurately controlled, and the obtained aluminum hydroxide adjuvant is poor in uniformity are solved, the preparation method is simple, complex organic solvents do not need to be adopted, and the preparation method is suitable for large-scale production.

Description

Technical Field

[0001] The present invention relates to the field of aluminum hydroxide adjuvants, and specifically to a nano-level aluminum hydroxide adjuvant, its preparation method and application. Background Art

[0002] An adjuvant refers to a substance that, when mixed with an antigen and injected into an animal body, can non-specifically enhance the body's specific immune response to the antigen. Adjuvants can induce a long-term and highly efficient specific immune response in the body, improve the body's protection ability, and at the same time reduce the dosage of immune substances and lower the production cost of vaccines. Currently, only a few are approved for use in human vaccines. Aluminum adjuvants include two types: aluminum hydroxide adjuvant and aluminum phosphate adjuvant. Among them, aluminum hydroxide adjuvant is a common immune enhancer and is the most widely used, with a usage history of nearly a hundred years.

[0003] The aluminum hydroxide adjuvant particles are uniformly fine, have a large specific surface area, and a very high adsorption rate. Its preparation method is usually to add an alkali solution to an aluminum salt solution to form fine aluminum compound particles, which aggregate and precipitate with each other. During the preparation process of aluminum hydroxide adjuvant particles, affected by factors such as the temperature and pH value of the reaction system, the particle size of the formed colloid is different, thus affecting its immune enhancement effect. The prior art generally uses aluminum chloride to react with sodium hydroxide, accurately controls the reaction rate, monitors the pH value of the system, uses a high-pressure homogenizer to generate an aluminum hydroxide colloid with an adjustable particle size, samples and detects the physical and chemical indexes, and obtains a product with a target concentration after vacuum concentration, and is stored in sub-packages after moist heat sterilization.

[0004] In the prior art, the particle size of the aluminum hydroxide adjuvant product is too large to pass through a 0.22 μm sterilizing filter element, so it is necessary to operate under full aseptic conditions or be treated by moist heat sterilization. Full aseptic operation greatly increases the operation difficulty and production cost. Moist heat sterilization is a method of sterilization carried out in saturated steam, boiling water or flowing steam, which may affect its adsorption effect on the antigen. For example, in the method disclosed in Chinese Patent CN113666404B, aluminum chloride reacts with sodium hydroxide, the reaction rate is controlled, the pH value of the system and the particle size of the reaction product are monitored to generate an aluminum hydroxide colloid with a particle size less than 1 μm. The above method uses high-pressure steam sterilization, and multiple high-pressure sterilizations may affect its adsorption effect on the antigen. Although the product can kill microorganisms by using ionizing radiation such as γ-rays and electron beams, a relatively high radiation dose is required for complete sterilization, which may cause adverse changes in the product; unknown secondary products may be generated during the irradiation process.

[0005] In addition, there are some other problems with aluminum hydroxide adjuvants prepared by the prior art. First, the particle size uniformity of the product is poor. For example, in the method disclosed in Chinese Patent CN108066759A, potassium alum is added to a sodium chloride solution and then sodium hydroxide is added dropwise; the method disclosed in Patent CN112569350A is similar, where aluminum chloride is added to a salt solution and then sodium hydroxide is added dropwise, and aluminum adjuvants with different crystal structures are obtained by controlling the pH value of the end solution; the particle size uniformity of the aluminum hydroxide produced by the above methods is poor, and adverse reactions are likely to occur after local injection.

[0006] Second, the particle size of the product cannot be precisely controlled. For example, in Chinese Patent CN113559255A, an aluminum chloride solution is added to an ammonia water solution in a spray form to obtain an aluminum hydroxide adjuvant; this method cannot accurately control the particle size of the product. Although the prior art can also use the cavitation effect generated by high-frequency vibration to generate instant high temperature and high pressure inside the material, thereby generating strong shear force, impact force and tensile force between the material particles to achieve the purpose of crushing. However, it is completed instantaneously and the crushing process is intense, and process monitoring cannot be carried out.

[0007] Third, complex organic solvents are required in the preparation process. For another example, Patent CN201010533334.7 discloses a preparation process of nano-aluminum hydroxide adjuvant. Benzalkonium bromide, n-octanol, and cyclohexane are used in the reaction to obtain the final product with a small particle size of the prepared aluminum adjuvant. However, it uses a variety of organic solvents, and acetone is added for demulsification after the reaction process. It is not easy to remove and is prone to residue, which is likely to cause adverse reactions. Even if the influence of organic solvent residue can be removed by using high temperature multiple times, multiple high temperatures will also affect the product performance. Summary of the Invention

[0008] In view of this, the technical problem to be solved by the present invention is to provide a nano-level aluminum hydroxide adjuvant, its preparation method and application. The preparation method provided by the present invention can precisely control the particle size of the obtained aluminum hydroxide adjuvant to be nano-level, and complex organic solvents are not required in the preparation process; the obtained aluminum hydroxide adjuvant has uniform particle size and good stability, is easy to disperse, and at the same time, its nano-level particle size enables it to use a filter element for sterilization to avoid the influence of high-temperature sterilization on performance.

[0009] The present invention provides a preparation method of a nano-level aluminum hydroxide adjuvant, comprising the following steps:

[0010] S1) Add an aluminum chloride solution to a sodium hydroxide solution for reaction;

[0011] S2) Disperse the material obtained in step S1) in the presence of a colloid stabilizer, then carry out aging and static stratification in sequence, and take the lower layer liquid obtained after static stratification for dialysis, vacuum concentration and sterilization in sequence to obtain the aluminum hydroxide adjuvant;

[0012] The colloid stabilizer is sodium dodecyl sulfate; the dispersion is carried out at a rotation speed of 6000 r / min to 8000 r / min.

[0013] The colloid stabilizer can coat the surface of colloid particles, reduce the surface energy and viscosity, prevent the contact and aggregation of particles among colloids, and thus maintain the dispersed state of the colloid; however, not all colloid stabilizers can coat on the surface of colloid particles to play a significant colloid stabilizing effect. In the present invention, sodium dodecyl sulfate (SDS) is used as the colloid stabilizer. As an anionic surfactant, SDS can play a unique colloid stabilizing effect in the present invention. It can adsorb on the surface of aluminum hydroxide particles through electrostatic interaction, so that a layer of alkyl chains covers the surface of aluminum hydroxide particles, thereby weakening the hydrophilicity, forming a monolayer of particles adsorbed on the gas-liquid interface, playing a role in foaming / stabilizing foam, enhancing the contact between the gas and liquid phases, and promoting the formation of hydrates. The addition amount of the colloid stabilizer in the present invention is 0.1 wt% to 0.4 wt% of the material obtained in step S1).

[0014] Under the action of sodium dodecyl sulfate, the present invention further conducts high-speed dispersion and granulation on the aluminum hydroxide generated by the reaction of aluminum chloride and sodium hydroxide, which can solve problems such as aggregation and poor dispersibility of aluminum hydroxide colloid before aging and make the aluminum hydroxide colloid reach the nanometer level. Finally, a nano-level aluminum hydroxide colloid with good distribution uniformity and a low PDI value (polydispersity index) is obtained. The present invention conducts dispersion at a rotation speed of 6000 r / min to 8000 r / min to obtain the target particle size of the product in this way and prevent the product structure from being affected by too high a speed. In addition, different from directly using a high-pressure homogenizer for granulation in the prior art, the present invention can obtain a nano-level aluminum hydroxide colloid with stable solution properties through dispersion and granulation.

[0015] The time of the dispersion in the present invention is based on whether the target particle size is reached. In order to make the particle size of the obtained aluminum hydroxide colloid reach the nanometer level, the time of the dispersion is preferably 8 min to 15 min; by controlling the dispersion time, on the one hand, the particle size of the product can be controlled, and on the other hand, the distribution uniformity of the aluminum hydroxide colloid and the low PDI value can be further promoted. The dispersion in the present invention is carried out at a temperature below 30 °C, preferably 15 °C to 30 °C. During the dispersion process, the cutter head of the disperser generates heat, and the temperature during dispersion is controlled to avoid local temperature rise causing changes in the colloid structure.

[0016] The present invention first adds an aluminum chloride solution to a sodium hydroxide solution for reaction. The present invention first adds an aluminum chloride solution to a sodium hydroxide solution to react to form aluminum hydroxide particles. The relevant chemical reaction equation is: 4NaOH + AlCl3 = NaAlO2 + 3NaCl + H2O; AlCl3 + 3NaAlO2 + 6H2O = 4Al(OH)3 (precipitate) + 3NaCl. In certain embodiments of the present invention, the concentration of the aluminum chloride solution is 0.1 mo / L to 0.2 mo / L, and the concentration of the sodium hydroxide solution is 0.2 mol / L to 0.4 mol / L.

[0017] Specifically, the present invention first reacts by adding the aluminum chloride solution to the sodium hydroxide solution at a temperature of 58 °C to 62 °C at a rate of 6 mL / min to 10 mL / min until the pH is 6.5 to 7.0. More specifically, the present invention first stirs the sodium hydroxide solution at a rotation speed of 150 r / min to 250 r / min at a temperature of 58 °C to 62 °C while adding the aluminum chloride solution to it at a rate of 6 mL / min to 10 mL / min. When the pH of the reaction solution is 8.0 to 8.5, the addition rate of the aluminum chloride solution is reduced. When the pH of the reaction solution is 7.0 to 7.5, the addition of the aluminum chloride solution is stopped, and stirring is maintained for 25 min to 35 min. Then, the aluminum chloride solution is continuously added to the reaction solution until the pH of the reaction solution reaches 6.5 to 7.0, at which point the addition of the aluminum chloride solution is stopped, and heat preservation and stirring are continued for 0.8 h to 1.2 h. Without calculating the time for maintaining stirring after stopping the addition of the aluminum chloride solution, the total duration of the operation of adding the aluminum chloride solution in the present invention is 0.8 h to 1.2 h, preferably 1 h.

[0018] The present invention preferably uses a pitched blade turbine agitator for stirring. The pitched blade turbine agitator is also called a curved blade vortex agitator. Using a pitched blade turbine agitator enables the materials to be quickly mixed, resulting in higher mixing efficiency. The curved design of the blades of the agitator can generate a strong axial flow during rotation, which helps to lift and circulate the materials. It is suitable for processing materials with higher viscosity or a tendency to precipitate, and can effectively prevent particle aggregation caused by the continuous increase in salt content during the reaction process, the significant reduction in the size of the ionic cloud and the strength of the electrostatic force, the weakening of the repulsive force, and the decrease in the potential barrier height, and increases the uniformity of the particle size distribution.

[0019] The present invention preferably uses a multi-droplet addition device to add an aluminum chloride solution to a sodium hydroxide solution, which can make the reaction more complete, has good real-time control of pH, and does not increase production costs. The multi-droplet addition device described in the present invention includes: a disk body having a droplet addition hole penetrating through its surface, a positioning column, and a droplet addition pipeline. One end of the positioning column is fixedly connected to the middle position of the disk body correspondingly, the other end of the positioning column is provided with a reduced diameter, and extends outward along the outer normal direction of the disk body surface. The droplet addition holes are annularly arranged on the disk body with the positioning column as the axis.

[0020] After performing step S1) of the present invention, the material obtained in step S1) is dispersed in the presence of a colloid stabilizer. The colloid stabilizer described in the present invention is the same as the foregoing and will not be elaborated. The dispersion described in the present invention is the same as the foregoing and will not be elaborated. In some embodiments of the present invention, the present invention preferably uses a high-speed disperser for dispersion; the particle size is adjusted by dispersion using the disperser. The disperser is easy to operate and has no destructive effect on the colloid. The high-speed dispersion by the disperser can improve the disadvantages of poor uniformity of the colloid particle size distribution and a large PDI value, and the sampling detection is convenient, which is convenient for parallel amplification.

[0021] After the material obtained in step S1) of the present invention is dispersed in the presence of a colloid stabilizer, aging and static layering are carried out in sequence. The lower layer liquid obtained after static layering is subjected to dialysis, vacuum concentration, and sterilization in sequence to obtain an aluminum hydroxide adjuvant. Specifically, after the material obtained in step S1) of the present invention is dispersed in the presence of a colloid stabilizer, the temperature is raised for aging. After the aging is completed, the heating is stopped and the temperature is naturally cooled to room temperature, and then it is left standing overnight for static layering. Then, the lower layer liquid obtained after static layering is subjected to dialysis, vacuum concentration, and sterilization in sequence to obtain an aluminum hydroxide adjuvant.

[0022] The temperature of the aging described in the present invention is 70°C to 90°C, and the time of the aging is 1.5 h to 2.5 h. Through temperature-controlled aging in the present invention, the aluminum hydroxide colloid becomes more ordered during the aging process, the particle aggregation degree decreases, and the stability in the solution increases.

[0023] The function of the dialysis described in the present invention is to remove SDS to ensure that its properties are not affected by the colloid stabilizer. Specifically, water is used for running dialysis, and the dialysis bag is kneaded 2 to 4 times every day during the dialysis process to mix the aluminum hydroxide colloid in the bag. The time of the dialysis described in the present invention is 1.5 to 3 days.

[0024] The vacuum concentration described in the present invention is carried out at 45°C to 50°C. The aluminum content is estimated according to the feeding amount, and after concentrating to the target concentration, it is stirred for 50 min to 70 min under the condition that the stirring speed is 200 rpm / min to 400 rpm / min. The vacuum concentration described in the present invention can control the concentration of the finally obtained product to meet different antigen requirements.

[0025] The sterilization in the present invention specifically refers to filtration sterilization. The filtration sterilization method removes bacteria in liquid or air by physical retention to achieve the purpose of sterility. Specifically, the sterilization in the present invention is: filtering and sterilizing through a pore size of 0.20 μm to 0.25 μm, preferably filtering and sterilizing through a pore size of 0.22 μm. More specifically, to avoid excessive pressure and leakage of the filter element, the filtration sterilization is carried out under a pressure of 100 mmHg to 200 mmHg. After the material obtained in step S1) is dispersed in the presence of a colloid stabilizer, the obtained aluminum hydroxide colloid can achieve filtration sterilization through a 0.22-μm sterilizing filter element due to its small particle size, solving the problem of inability to filter and sterilize, and the product properties before and after sterilization are not affected, avoiding the influence of moist heat sterilization on its antigen adsorption effect, and being applicable to the large-scale production of aluminum hydroxide adjuvant. In addition, the adjuvant after filtration sterilization has stable properties and can maintain its particle stability within a wide pH range.

[0026] The preparation method of the nano-level aluminum hydroxide adjuvant provided by the present invention uses aluminum chloride and sodium hydroxide to react, accurately controls the reaction rate, monitors the pH value of the system, and makes the aluminum hydroxide colloid in the process reach the nano-level by adding a colloid stabilizer and using a high-speed disperser for size adjustment, enabling filtration sterilization, and finally obtaining a nano-level aluminum hydroxide adjuvant with stable properties and uniform particles. This method is simple and easy to operate and is applicable to the large-scale production of aluminum hydroxide adjuvant.

[0027] The present invention also provides a nano-level aluminum hydroxide adjuvant obtained by the preparation method described in any one of the above. The average particle size of the nano-level aluminum hydroxide adjuvant obtained by the preparation method of the present invention is 70 nm to 90 nm.

[0028] The present invention also provides the application of the nano-level aluminum hydroxide adjuvant obtained by the preparation method described in any one of the above or the nano-level aluminum hydroxide adjuvant described in any one of the above in the preparation of vaccines. The nano-level aluminum hydroxide adjuvant of the present invention has excellent suspension stability, is easy to disperse, and has a fluffy structure, which is beneficial to obtaining a product with better uniformity in the process of vaccine production and application.

[0029] The present invention provides a nano-level aluminum hydroxide adjuvant, its preparation method and application. The present invention uses sodium dodecyl sulfate as a colloid stabilizer to further perform high-speed dispersion and size adjustment on the aluminum hydroxide generated by the reaction of aluminum chloride and sodium hydroxide, which can solve problems such as aggregation and poor dispersibility of the aluminum hydroxide colloid before aging and make the aluminum hydroxide colloid reach the nano-level, solve the problem that the prior art cannot filter and sterilize the aluminum hydroxide colloid through filtration, and finally obtain a nano-level aluminum hydroxide colloid with good distribution uniformity and a low PDI value, solve the problems that the prior art cannot accurately control the particle size of the aluminum hydroxide adjuvant and the obtained aluminum hydroxide adjuvant has poor uniformity, and the preparation method is simple and does not require the use of complex organic solvents, being suitable for large-scale production. Brief Description of the Drawings

[0030] Figure 1 It is a schematic diagram of the folded-blade turbine stirring paddle described in the present invention;

[0031] Figure 2 It is a schematic diagram of the multi-dropwise addition device described in the present invention;

[0032] Figure 3 It is a process flow chart of the preparation of the nano-level aluminum hydroxide adjuvant described in the present invention;

[0033] Figure 4 It is a particle size detection diagram of the aluminum hydroxide adjuvant product before filtration and sterilization;

[0034] Figure 5 It is a particle size detection diagram of the aluminum hydroxide adjuvant product after filtration and sterilization;

[0035] Figure 6 It is a ZETA potential diagram of the aluminum hydroxide adjuvant product before filtration and sterilization;

[0036] Figure 7 It is a ZETA potential diagram of the aluminum hydroxide adjuvant product after filtration and sterilization;

[0037] Figure 8 It is a particle size detection diagram of the aluminum hydroxide adjuvant product obtained by using SDBS as a colloid stabilizer;

[0038] Figure 9 It is a ZETA potential diagram of the aluminum hydroxide adjuvant product obtained by using SDBS as a colloid stabilizer. Detailed Description of the Invention

[0039] The present invention discloses a nano-level aluminum hydroxide adjuvant, its preparation method and application. Those skilled in the art can draw on the content of this article and appropriately modify the process parameters to achieve. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art, and they are all considered to be included in the present invention. The methods and applications of the present invention have been described through preferred embodiments, and those skilled in the art can obviously make changes or appropriate modifications and combinations to the methods and applications in this article without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0040] The main instrument and equipment used in the specific implementation mode of the present invention are shown in Table 1:

[0041] Table 1

[0042] Instrument Name Model Equipment Manufacturer Cantilever Mechanical Stirrer JJ-1BA Changzhou Runhua Multi-parameter Tester S470 METTLER TOLEDO Rotary Evaporator RE-52A Shanghai Yarong Double-sided Clean Bench for Two Persons SW-CJ-2F Sujing Installation Electronic Balance TD20002A LICHEN Peristaltic Pump MILLIPORE Hot Air Circulating Oven GZX-9246MBE Shanghai Boxun High-speed Disperser XHF-DY SCIENTZ

[0043] The main experimental reagents used in the specific implementation mode of the present invention are shown in Table 2:

[0044] Table 2

[0045] Name Batch Number Supplier Aluminum Chloride Anhydrous 20220106 Sinopharm Group Sodium Hydroxide 20230403 Sinopharm Group SDS 21117010270 GENVIEW SDBS 20240221 Sinopharm Group

[0046] The present invention uses a pitched-blade turbine agitator for agitation, as Figure 1 shown, Figure 1 which is a schematic diagram of the pitched-blade turbine agitator of the present invention.

[0047] The self-made perforated pipeline used in the present invention is the aforementioned multi-dropwise addition device, as Figure 2 shown, Figure 2 which is a schematic diagram of the multi-dropwise addition device of the present invention.

[0048] The general preparation process of the nano-level aluminum hydroxide adjuvant in the present invention is as Figure 3 shown, Figure 3 which is a process flow diagram of the preparation of the nano-level aluminum hydroxide adjuvant of the present invention.

[0049] The present invention is further described below in conjunction with embodiments:

[0050] Embodiment 1

[0051] ① Sterilize the required beakers, flasks, medicine spoons and other utensils by dry heat, soak the thermometer, agitator, dropping pipeline, etc. in alkali, and wash them with purified water before use.

[0052] ② Weigh 2.43 g of sodium hydroxide into a beaker, dissolve it with purified water and dilute it to 200 mL of solution. Cool the solution to room temperature for later use. Transfer the cooled solution to a flask, heat it up to 60 °C, and stir mechanically at 200 r / min.

[0053] ③ Weigh 2.74 g of anhydrous aluminum chloride into a beaker, dissolve it with purified water and dilute it to 200 mL of solution. There are white fumes and heat release during the dissolution process. Let it stand at room temperature for later use.

[0054] ④ Pump the solution in ③ into the solution in ② evenly by a peristaltic pump (using the self-made perforated pipeline), adjust the dropping speed to about 8 mL / min, control the reaction temperature at 60 °C, and the stirring speed at 200 r / min; as the dropping progresses, if the temperature rises too fast, cool it appropriately. White precipitates gradually precipitate. Take samples to monitor the pH value. When the pH of the solution is 8.5, reduce the dropping speed and continue dropping. Stop dropping when the pH is 7.5. Stir for half an hour and then continue dropping. Finally, stop dropping when the pH value of the solution is 6.8, and keep stirring while maintaining the temperature.

[0055] ⑤ Maintain the reaction system at 60 ± 2 °C, keep the stirring speed, and stir while maintaining the temperature for 1 hour. Naturally cool it to below 30 °C, add 0.8 g of SDS, disperse it with a high-speed disperser at 8000 r / min for 10 min. Take samples for detection after dispersion. The particle size has dropped below 100 nm, and then heat up and stir.

[0056] ⑥ After heating to 80 °C and aging for 2 hours, stop heating, let it cool naturally to room temperature, and then let it stand overnight.

[0057] ⑦ Separate the supernatant the next day. Put the lower layer liquid into a dialysis bag and dialyze it with running purified water. During dialysis, knead the dialysis bag 3 times a day to mix the aluminum hydroxide in the bag, and carry out dialysis for 2 days.

[0058] ⑧ Concentrate the material under reduced pressure at 45 - 50 °C, estimate the volume to be distilled, concentrate to about 10 mg / mL (calculated by aluminum content), and stir for 60 min at a stirring speed of 300 rpm / min.

[0059] ⑨ Inject the aluminum hydroxide solution into the filter, and pay attention to controlling the pressure at 180 mmHg to pass through a 0.22 μm sterilizing filter element to obtain the aluminum hydroxide adjuvant product, which is stored for later use.

[0060] The comparison of the particle sizes of the product before and after filtration and sterilization is as Figure 4 and Figure 5 shown. Figure 4 Figure for the particle size detection of the aluminum hydroxide adjuvant product before filtration and sterilization, Figure 5 Figure for the particle size detection of the aluminum hydroxide adjuvant product after filtration and sterilization.

[0061] The comparison of the ZETA potential measurements of the product before and after filtration and sterilization is as Figure 6 and Figure 7 shown. Figure 6 ZETA potential diagram of the aluminum hydroxide adjuvant product before filtration and sterilization, Figure 7 ZETA potential diagram of the aluminum hydroxide adjuvant product after filtration and sterilization.

[0062] Comparative Example 1

[0063] ① Take the required beakers, flasks, spoons and other utensils for the experiment and perform dry heat sterilization treatment, soak the thermometer, stirring paddle, dropping pipeline, etc. with caustic soda, and wash them with purified water before use.

[0064] ② Weigh 2.47 g of sodium hydroxide in a beaker, dissolve it with purified water and dilute it to 200 mL of solution. Let the solution cool to room temperature for later use. Transfer the cooled solution to a flask, heat it to 60 ± 2 °C, and stir mechanically at 200 r / min.

[0065] ③ Weigh 2.76 g of anhydrous aluminum chloride in a beaker, dissolve it with purified water and dilute it to 200 mL of solution. There are white fumes and heat release during the dissolution process. Let it stand at room temperature for later use.

[0066] ④ Pump the solution in ③ into the solution in ② at a constant speed using a peristaltic pump (using a self-made perforated pipeline), adjust the dropping speed to about 8 mL / min, control the reaction temperature at 60 ± 2 °C, and the stirring speed at 200 r / min; when white precipitate gradually appears, take a sample to monitor the pH value. When the pH of the solution is 8.5, reduce the dropping speed and continue dropping. Stop dropping when the pH is 7.5. After stirring for half an hour, continue dropping. Finally, stop dropping when the pH value of the solution is 6.8, and keep stirring while maintaining the temperature.

[0067] ⑤ Maintain the reaction system at 60 ± 2 °C, keep the stirring speed, and stir while maintaining the temperature for 1 hour. Naturally cool down to below 30 °C, add 0.8 g of SDBS (sodium dodecylbenzenesulfonate, hereinafter referred to as SDBS), and disperse it with a high-speed disperser at 8000 r / min for 10 min. After dispersion, take a sample for detection. The measured particle size is above 180 nm. Disperse it again for 10 min. The particle size does not change, and the PDI value is 1.000, indicating that its particle size is uneven and the particle size distribution is not concentrated. Stop dispersion and heat and stir the solution.

[0068] ⑥ After aging at 80 °C for 2 hours, stop heating, naturally cool down to room temperature, and then let it stand overnight.

[0069] ⑦ Separate the supernatant the next day. Put the lower-layer liquid into a dialysis bag and dialyze it with purified water flowing. During dialysis, knead the dialysis bag 3 times a day to mix the aluminum hydroxide in the bag, and perform dialysis for 2 days.

[0070] ⑧ Control the material at 45 - 50 °C for vacuum concentration. Estimate the volume to be distilled, and concentrate it to about 10 mg / mL (calculated based on the aluminum content), and stir for 60 min under the condition of a stirring speed of 300 rpm / min.

[0071] ⑨ Inject the aluminum hydroxide solution into the filter. Control the pressure at 180 mmHg and it cannot pass through a 0.22 μm sterilizing filter element. Increase the pressure to 200 mmHg and the solution still cannot pass through the 0.22 μm sterilizing filter element. Stop filtration, collect the solution for particle size and ZETA potential measurement, as Figure 8 and Figure 9 shown, Figure 8 is the particle size detection chart of the aluminum hydroxide adjuvant product obtained using SDBS as a colloid stabilizer, Figure 9 is the ZETA potential chart of the aluminum hydroxide adjuvant product obtained using SDBS as a colloid stabilizer. As Figure 8 can be seen, due to the poor particle size uniformity, some particle sizes are too large to be shown in the figure, and some overly large particle size values have raised the overall particle size average value.

[0072] ⑩ From the detection results, it can be judged that the particle size of this product is relatively large, and it is impossible to achieve filtration sterilization. At the same time, the absolute value of the Zeta potential is relatively low, the system tends to coagulate or aggregate, and the system stability is poor.

[0073] The above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent substitutions or changes, shall be covered by the protection scope of the present invention.

Claims

1. A method for preparing a nano-scale aluminum hydroxide adjuvant, characterized in that: The following steps are involved: S1) adding aluminum chloride solution to sodium hydroxide solution to react; S2) dispersing the material obtained in step S1) in the presence of a colloidal stabilizer, and then aging and stratifying in sequence, taking the lower layer liquid obtained after stratification and dialysis, vacuum concentration and sterilization in sequence to obtain an aluminum hydroxide adjuvant; The colloidal stabilizer is sodium dodecyl sulfate; the dispersion is carried out at a rotation speed of 6000 r / min to 8000 r / min.

2. The preparation method according to claim 1, characterized in that: In step S2), the amount of the colloid stabilizer added is 0.1wt% to 0.4wt% of the material obtained in step S1).

3. The preparation method according to claim 1, characterized in that: In step S2), the dispersion time is 8 min to 15 min.

4. The preparation method according to claim 1, characterized in that: In step S2), the dispersion is performed at a temperature below 30°C.

5. The preparation method according to claim 1, characterized in that: Step S1) is specifically: At a temperature of 58° C. to 62° C., the aluminum chloride solution is added to the sodium hydroxide solution at a rate of 6 mL / min to 10 mL / min to react until the pH is 6.5 to 7.

0.

6. The preparation method according to claim 1, characterized in that: In step S2), the aging temperature is 70° C. to 90° C., and the aging time is 1.5 h to 2.5 h.

7. The preparation method according to claim 1, characterized in that: In step S2), the sterilization is specifically: filtering and sterilizing through a pore size of 0.20 μm to 0.25 μm.

8. The preparation method according to claim 7, characterized in that: Filtration sterilization is performed at a pressure of 100 mmHg to 200 mmHg.

9. The nano-scale aluminum hydroxide adjuvant obtained by the preparation method according to any one of claims 1 to 8.

10. Use of the nano-sized aluminum hydroxide adjuvant obtained by the preparation method according to any one of claims 1 to 8 or the nano-sized aluminum hydroxide adjuvant according to claim 8 or 9 in the preparation of vaccines.

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