Method for efficiently preparing nano-emulsion and nano-particles with uniform and controllable size based on spontaneous emulsification

Abstract

The invention provides a method for efficiently preparing a nano-emulsion with uniform and controllable size based on spontaneous emulsification. The method comprises the following steps: taking an organic solvent as an oil phase solution; or dissolving a functional high-molecular polymer or / and functional organic molecules in an organic solvent to form an oil phase solution; the organic solvent is insoluble in water or slightly soluble in water; dissolving a nonionic surfactant in water to form a water phase solution; or dissolving a nonionic surfactant and a substance capable of reacting with the functional organic molecules in water to form a water-phase solution; the nonionic surfactant can be dissolved in both the oil phase solution and the water, and the solubility of the nonionic surfactant in the oil phase solution is greater than the solubility of the nonionic surfactant in the water; and adding the oil-phase solution into the water-phase solution, and stirring or shaking for 1-5 minutes to obtain the nano-emulsion. The invention also provides a method for preparing nano-particles by taking the nano-emulsion as a template. According to the method, low-energy-consumption, convenient, efficient and controllable preparation of the nano-emulsion and the nano-particles with uniform sizes can be realized.

Description

Technical Field

[0001] The present invention belongs to the field of preparation of nanoemulsions and nanoparticles for biomedicine, and relates to a method for efficiently preparing size-uniform and controllable nanoemulsions and nanoparticles based on spontaneous emulsification. Background Art

[0002] Nanoemulsions and nanoparticles have characteristics such as small size, large specific surface area, and high bioavailability, and are widely used in targeted delivery, drug controlled release, diagnostic imaging, etc., and play an important role in the fields of biomedicine and the like. Nanoemulsions are mainly prepared by two-phase emulsification, and synthesizing nanoparticles using nanoemulsions as templates is an important method for preparing nanoparticles. The efficient preparation of nanoemulsions is of great significance for the applications of both nanoemulsions and nanoparticles. However, there are still great challenges in the efficient preparation of nanoemulsions at present.

[0003] Common methods for preparing nanoemulsions include high-pressure homogenization method, ultrasonic emulsification method, phase inversion temperature method, and spontaneous emulsification method, etc. The high-pressure homogenization method needs to be operated under relatively high pressure, with high energy consumption and extremely low energy utilization rate, and the size of the prepared nanoemulsions is large and the size is not easy to control. The ultrasonic emulsification method also needs to use high-energy ultrasound, which not only has high energy consumption, but also needs to regulate various factors such as the ultrasonic reaction chamber and operating conditions, and is difficult to implement in actual production. The phase inversion temperature method requires a rapid heating and cooling process, has high requirements for experimental equipment, and has a complex operation process, and the stability of the prepared nanoemulsions still needs to be improved. When immiscible liquids under non-equilibrium conditions come into contact, the chemical potential gradient between the two phases will trigger spontaneous emulsification. In a binary liquid-liquid system, spontaneous nanoemulsification is usually achieved by changing the properties of surfactants (such as solubility and optimal curvature) to trigger interfacial instability, and they usually require using temperature, pH, composition, and chemical reactions as triggering factors to trigger interfacial instability. In addition, interfacial bubble rupture, steam condensation, and solute transfer allow the destruction of the stability of the surfactant-loaded interface without changing the properties of the surfactant for spontaneous nanoemulsification. In order to obtain more stable and uniform nano-droplets, these methods still need to add a high concentration of surfactants, which brings challenges to its industrial implementation. More importantly, these methods require a time-consuming evolution from a non-equilibrium system to an equilibrium nanoemulsion, resulting in a long preparation time and low efficiency of preparing nanoemulsions. Therefore, there is an urgent need to develop a preparation method for nanoemulsions and nanoparticles with low energy consumption, low requirements for equipment, convenient operation, and higher preparation efficiency at present. Summary of the Invention

[0004] In view of the problems existing in the prior art when preparing nanoemulsions based on spontaneous emulsification, such as long time consumption, low preparation efficiency, high energy consumption, high requirements for equipment, and complex operation, the present invention provides a method for efficiently preparing size-uniform and adjustable nanoemulsions and nanoparticles based on the mechanism of spontaneous nanoemulsification induced by surfactant cross-interface mass transfer and flow-induced interface instability, so as to achieve low-energy consumption, convenient, and efficient controllable preparation of size-uniform nanoemulsions and nanoparticles.

[0005] To achieve the above-mentioned invention purpose, the technical solution adopted by the present invention is as follows:

[0006] A method for efficiently preparing size-uniform and adjustable nanoemulsions based on spontaneous emulsification, comprising the following steps:

[0007] (1) Prepare an oil-phase solution and an aqueous-phase solution

[0008] Prepare the oil-phase solution: Use an organic solvent as the oil-phase solution; or dissolve a functional polymer or / and a functional organic molecule in an organic solvent to form an oil-phase solution; the organic solvent is insoluble or slightly soluble in water;

[0009] Prepare the aqueous-phase solution: Dissolve a nonionic surfactant in water to form an aqueous-phase solution; or dissolve a nonionic surfactant and a substance capable of reacting with the functional organic molecule in water to form an aqueous-phase solution; the concentration of the nonionic surfactant in the aqueous-phase solution is 0.1 wt% - 1.1 wt%; the nonionic surfactant can dissolve in both the organic solvent and water, and the solubility of the nonionic surfactant in the organic solvent is greater than the solubility of the nonionic surfactant in water;

[0010] (2) Prepare the nanoemulsion

[0011] Add the oil-phase solution to the aqueous-phase solution, control the volume ratio of the aqueous-phase solution to the oil-phase solution to be at least 20, stir or shake for 1 - 5 min, and the nanoemulsion is obtained.

[0012] In the technical solution of the above method for efficiently preparing size-uniform and adjustable nanoemulsions, the organic solvent used when preparing the oil-phase solution has no other special requirements except meeting the two requirements of being insoluble or slightly soluble in water and the solubility of the nonionic surfactant in the organic solvent being greater than the solubility of the nonionic surfactant in water. In practical applications, the organic solvent can be selected according to the specific nonionic surfactant used. Feasible organic solvents include halogenated alkanes, mineral oils, etc., but are not limited to halogenated alkanes and mineral oils.

[0013] In the technical solution of the above method for efficiently preparing nanoemulsions with uniform and adjustable sizes, when formulating the aqueous solution, the non-ionic surfactant used only needs to meet two requirements: being soluble in water and having a higher solubility in the organic solvent than in water. There are no other special requirements for the non-ionic surfactant. In practical applications, the non-ionic surfactant can be selected according to the specific organic solvent used. Feasible non-ionic surfactants include at least one of the Pluronic series surfactants, the Tween series surfactants, and Triton X-100, but are not limited to the non-ionic surfactants listed above. For the Pluronic series surfactants, it can be at least one of Pluronic F127, Pluronic L64, Pluronic L61, Pluronic F108, Pluronic F68, etc. For the Tween series surfactants, it can be at least one of Tween 80, Tween 20, etc.

[0014] In step (2) of the technical solution of the above method for efficiently preparing nanoemulsions with uniform and adjustable sizes, it is preferably to control the volume ratio of the aqueous solution to the oil phase solution to be 20:(0.4 - 1).

[0015] In the technical solution of the above method for efficiently preparing nanoemulsions with uniform and adjustable sizes, when step (2) uses stirring to prepare the nanoemulsion, it is preferably to control the stirring speed to be 500 - 1000 rpm.

[0016] In the technical solution of the above method for efficiently preparing nanoemulsions with uniform and adjustable sizes, the droplet size of the prepared nanoemulsion is 20 - 550 nm, and the polydispersity index of the droplet size of the nanoemulsion prepared by this method does not exceed 0.2.

[0017] In the technical solution of the above method for efficiently preparing nanoemulsions with uniform and adjustable sizes, the material of the container used in step (2) when preparing the nanoemulsion should meet the requirement that the container does not react with the oil phase solution and the aqueous solution. Usually, a glass container can be used to prepare the nanoemulsion.

[0018] In the technical solution of the above method for efficiently preparing nanoemulsions with uniform and adjustable sizes, by adjusting the type of non-ionic surfactant in the aqueous solution, the type of organic solvent used when formulating the oil phase solution, etc., the droplet size of the prepared nanoemulsion can be adjusted. For example, the present invention has confirmed through experiments that when multiple different non-ionic surfactants are used in combination, by adjusting the proportional relationship of different types of non-ionic surfactants in the aqueous solution, the droplet size of the prepared nanoemulsion can be adjusted.

[0019] The present invention also provides a method for preparing nanoparticles, comprising the following steps:

[0020] (1) Prepare a nanoemulsion by using the above method for efficiently preparing a size-uniform and controllable nanoemulsion based on spontaneous emulsification. When preparing the nanoemulsion, the oil-phase solution used contains a functional polymer or / and a functional organic molecule;

[0021] (2) Heat the nanoemulsion obtained in step (1) to completely volatilize the organic solvent in the nanoemulsion, thereby obtaining the nanoparticles.

[0022] In the technical solution of the above method for preparing nanoparticles, the heating temperature of the nanoemulsion in step (2) can be flexibly adjusted according to the boiling point of the organic solvent used when formulating the oil-phase solution, on the basis of not affecting the activities of the functional polymer and the functional organic molecule.

[0023] In the technical solution of the above method for preparing nanoparticles, the functional polymer and the functional organic molecule can be selected according to actual application requirements; the concentrations of the functional polymer and the functional organic molecule in the oil-phase solution can be determined according to actual application requirements and the solubility of the functional polymer and the functional organic molecule in the organic solvent. Feasible functional polymers include biodegradable polymers, temperature-responsive polymers, pH-responsive polymers, conductive polymers, etc., but the feasible functional polymers are not limited to the specific polymers listed above. Feasible functional organic molecules include organic fluorescent molecules, oil-soluble drugs, functional organic precursors, etc., but the feasible functional organic molecules are not limited to the organic molecules listed above.

[0024] In the technical solution of the above method for preparing nanoparticles, the nanoparticles include forms such as polymer nanoparticles, nanovesicles, and nanocrystals. The nanoparticles are composed of a functional polymer, or composed of a functional polymer and a functional organic molecule, or formed by reacting a functional organic molecule (such as a functional organic precursor) with a substance in the aqueous phase solution that can react with the functional organic molecule (such as a functional organic precursor).

[0025] The particle size of the nanoparticles prepared by the technical solution of the above method for preparing nanoparticles is generally between 25 and 570 nm. In practical applications, by adjusting the concentrations of the functional polymer or / and the functional organic molecule in the oil-phase solution, and the droplet size of the nanoemulsion, the size of the nanoparticles can be flexibly adjusted.

[0026] In the above technical solution, the "efficient preparation" refers to high-efficiency preparation.

[0027] The principle of the present invention for efficiently preparing a size-uniform and controllable nanoemulsion based on spontaneous emulsification is mainly as follows:

[0028] The method of the present invention realizes the preparation of nanoemulsion based on the mechanism of spontaneous nanoemulsification induced by the interfacial instability caused by the mass transfer flow of surfactants across the interface. Specifically, the organic solvent used to prepare the oil-phase solution is insoluble or slightly soluble in water, and the solubility of the nonionic surfactant in the organic solvent is greater than that in water. The surfactant in the aqueous-phase solution diffuses from the aqueous-phase solution to the oil-phase solution, so that the surfactant can be rapidly enriched at the oil-water interface, and a supersaturated region with a local concentration much higher than the surfactant concentration in the bulk phase is generated. The impact of surfactant flow and the excess of surfactant synergistically induce the instability of the molecular-level interface, resulting in rapid spontaneous emulsification in the surfactant concentration supersaturated region, and the formation of tiny droplets through the self-assembly of surfactants. Then, these tiny droplets undergo repeated emulsification cycles to finally obtain nano-sized emulsion droplets.

[0029] Compared with the prior art, the technical solution of the present invention has the following beneficial technical effects:

[0030] 1. The present invention provides a method for efficiently preparing nanoemulsions with uniform and adjustable sizes based on spontaneous emulsification. By reasonably designing the formulations of the oil-phase solution and the aqueous-phase solution and cooperating with appropriate operations, the method can trigger interfacial instability and achieve spontaneous nanoemulsification without relying on temperature, pH, chemical reactions, etc. as triggering factors, and prepare nanoemulsions with uniform and adjustable sizes. The operation of preparing nanoemulsions by the method of the present invention is very simple, the reagents used are cheap and easily available, there is no need to rely on complex equipment, and there is no need to consume a large amount of energy. More importantly, after adding the oil-phase solution to the aqueous-phase solution, the nanoemulsion can be rapidly prepared by stirring or shaking for 1 to 5 minutes. Compared with the existing methods for preparing nanoemulsions, the method for preparing nanoemulsions of the present invention has the advantages of low energy consumption, low equipment requirements, simple operation and high production efficiency. The prepared nanoemulsions are stable, small in size, narrow in size distribution range and adjustable in size. Therefore, the method for preparing nanoemulsions of the present invention is not only conducive to popularization and application in actual production, but also conducive to improving the quality of nanoemulsions.

[0031] 2. The method for preparing the nanoemulsion according to the present invention can flexibly adjust the droplet size of the nanoemulsion. For example, when the method for preparing the nanoemulsion according to the present invention combines a variety of different non-ionic surfactants, by adjusting the proportional relationship and concentration of different types of non-ionic surfactants in the aqueous solution, the droplet size of the prepared nanoemulsion can be adjusted. The present invention has confirmed through experiments that when Lonikol L61 and Pluronic F127 are used in combination, by adjusting the mass ratio of Lonikol L61 to Pluronic F127 in the aqueous solution, a nanoemulsion with a particle size of 30 nm to 540 nm can be prepared.

[0032] 3. The present invention also provides a method for preparing nanoparticles. This method uses the nanoemulsion prepared by the method for preparing the nanoemulsion according to the present invention as a template, and nanoparticles can be prepared by solvent evaporation. This method is simple, efficient, and energy-saving, and can batch-produce nanoparticles with good morphological uniformity. By controlling the size of the nanoemulsion and the concentration of functional polymer or / and functional organic molecule in the oil phase solution, the size of the nanoparticles can be flexibly adjusted, which can solve the problem that it is difficult to prepare nanoparticles with good size uniformity and adjustable size based on nanoemulsions in the prior art, and at the same time overcome the problems of cumbersome operation and high energy consumption existing in the prior art when preparing nanoparticles.

[0033] 4. In the method for preparing nanoparticles according to the present invention, by adding a certain amount of functional polymer or / and functional organic molecule in the oil phase solution, nanoparticles with different properties and functions can be prepared, such as polymer nanoparticles, nanovesicles, and nanocrystals, etc. There are no special requirements for the functional polymer and functional organic molecule except meeting the solubility requirements, and the selection range is wider. At the same time, the size of the nanoparticles can be flexibly controlled, and this method has good versatility and is a general method for preparing nanoparticles with diverse functions.

[0034] 5. Taking the preparation of nanoparticles with an oil phase solution containing the model drug curcumin and poly (lactic-co-glycolic acid) as an example, the present invention has confirmed through experiments that the method of the present invention can achieve the dispersion of substances that are poorly soluble or insoluble in aqueous media in aqueous media. Description of the Drawings

[0035] Figure 1 Figure a shows the change in the particle size distribution of the nanoemulsion prepared in Example 1 with the concentration of F127 in the aqueous solution, Figure 1 Figure b shows the TEM image of the nanoemulsion prepared in Example 1 when the concentration of F127 in the aqueous solution is 0.2 wt%.

[0036] Figure 2Figures a - b and c - d are the particle size distribution diagram and TEM image of the nanoemulsion prepared in Example 2 using F108 and Tween 20 as surfactants.

[0037] Figure 3 Figures a - b are the particle size distribution diagram and TEM image of the nanoemulsion prepared in Example 3 using dichloromethane as the oil - phase solution. Figure 3 Figure c is the graph showing the change in the average particle size of the nanoemulsion prepared in Example 4 with the mass ratio of L61 to F127 in the aqueous - phase solution. Figure 3 Figure d is the TEM image of the nanoemulsion prepared in the Example when R = 0.1.

[0038] Figure 4 Figure a is the TEM image and particle size distribution diagram of the PLGA nanoparticles prepared in Example 5. Figure 4 Figure b is the fluorescence spectra of the PLGA nanoparticles encapsulating Cur and separate Cur, and the optical image of the aqueous solution of the PLGA nanoparticles encapsulating Cur prepared in Example 5.

[0039] Figure 5 Figures a - b are the TEM image and particle size distribution diagram of the PS - b - PB - b - PS nanovesicles prepared in Example 6. Figure 5 Figures c - d are the TEM image and particle size distribution diagram of the ZIF - 8 nanocrystals prepared in Example 7.

[0040] Figure 6 Figure a is the macroscopic image during the batch preparation of the nanoemulsion in Example 8. Figure 6 Figure b is the TEM image of the nanoemulsion prepared in the batch in Example 8. Figure 6 Figure c is the particle size distribution diagram of the nanoemulsion prepared in the batch in Example 8.

[0041] Figure 7 Figure a is the macroscopic image during the batch preparation of the nanoemulsion containing PLGA in Example 9. Figure 7 Figure b is the TEM image of the PLGA nanoparticles prepared in the batch in Example 9. Figure 7 Figure c is the particle size distribution diagram of the PLGA nanoparticles prepared in the batch in Example 9. Detailed implementation manners

[0042] The following further illustrates the method for efficiently preparing size - uniform and tunable nanoemulsions and nanoparticles based on spontaneous emulsification provided by the present invention through examples. It is necessary to point out that the following examples are only used to further illustrate the present invention and should not be construed as limiting the protection scope of the present invention. Those skilled in the art make some non - essential improvements and adjustments to the present invention based on the above - mentioned invention content for specific implementation, which still fall within the protection scope of the present invention.

[0043] In the following embodiments, the nanoemulsion is formed by dispersing an oil-phase solution in an aqueous-phase solution. The particle size of the nanoemulsion refers to the particle size of the nanoemulsion droplets (oil-phase droplets dispersed in the aqueous-phase solution), and the size of the nanoemulsion refers to the size of the nanoemulsion droplets (oil-phase droplets dispersed in the aqueous-phase solution).

[0044] Example 1

[0045] In this example, the effect of the concentration of the surfactant in the aqueous-phase solution on the size of the nanoemulsion prepared by the method of the present invention was investigated. The steps are as follows:

[0046] (1) Prepare an oil-phase solution and an aqueous-phase solution

[0047] Prepare the oil-phase solution: Use dichloromethane (DCM) as the oil-phase solution.

[0048] Prepare the aqueous-phase solution: Dissolve the surfactant Pluronic F127 (F127) in deionized water to prepare F127 aqueous solutions with F127 concentrations of 0.05 wt%, 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.5 wt%, and 1 wt% as the aqueous-phase solutions.

[0049] (2) Prepare the nanoemulsion by the spontaneous emulsification method

[0050] Take 4 mL of each aqueous-phase solution with different surfactant concentrations and add them to each glass vial. Then, use a micropipette to add 100 μL of the oil-phase solution to each glass vial, and then shake or stir for 1 min to obtain the nanoemulsion.

[0051] The variation of the particle size distribution of the nanoemulsion prepared in this example with the concentration of the surfactant in the aqueous-phase solution is as shown in Figure 1 Figure a. It can be seen from this figure that the concentration of the surfactant in the aqueous-phase solution has little effect on the particle size of the nanoemulsion, but has a certain effect on the polydispersity of the nanoemulsion. When the concentration of F127 in the aqueous-phase solution is 0.1 wt% - 1 wt%, the polydispersity index (PDI) of the nanoemulsion < 0.1, indicating that the size of the prepared nanoemulsion is uniform. Figure 1 Figure b is a transmission electron microscopy (TEM) image of the nanoemulsion prepared when the concentration of F127 in the aqueous-phase solution is 0.2 wt%. It can be seen from this figure that the size of the nanoemulsion is uniform and the morphology is good.

[0052] Example 2

[0053] In this example, it was investigated whether the method of the present invention is applicable to different non-ionic surfactants. The steps are as follows:

[0054] (1) Prepare the oil phase solution and the aqueous phase solution

[0055] Prepare the oil phase solution: Use DCM as the oil phase solution.

[0056] Prepare the aqueous phase solution: Dissolve different non-ionic surfactants in deionized water to prepare a surfactant solution with a concentration of 0.2 wt% as the aqueous phase solution. The non-ionic surfactants used specifically include: Pluronic F127 (F127), Pluronic L64 (L64), Pluronic L61 (L61), Pluronic F108 (F108), Pluronic F68 (F68), Tween 80, Tween 20, and Triton X-100.

[0057] (2) Prepare nanoemulsions by the spontaneous emulsification method

[0058] Take 4 mL of the aqueous phase solution with different surfactant types and add them to each glass vial respectively. Then use a micropipette to add 100 μL of the oil phase solution to each glass vial, and then shake or stir for 1 min to obtain nanoemulsions.

[0059] Perform TEM tests on the nanoemulsions prepared in this example and draw the particle size distribution diagrams of the nanoemulsions according to the TEM test results. It is found that when preparing nanoemulsions with the above different non-ionic surfactants to prepare the aqueous phase solution in this example, nanoemulsions with a narrow particle size distribution range and uniform particle size can be successfully prepared. Figure 2 Show the particle size distribution diagrams and TEM images of the nanoemulsions prepared with the aqueous phase solution formulated with some non-ionic surfactants in this example. Figure 2 Figures a - b in show the particle size distribution diagrams and TEM images of the nanoemulsions prepared with F108 as the surfactant, and figures c - d in show the particle size distribution diagrams and TEM images of the nanoemulsions prepared with Tween 20 as the surfactant. From Figure 2 It can be seen that the nanoemulsions prepared with the aqueous phase solution formulated with F108 and Tween 20 as the surfactants have a narrow particle size distribution range and uniform particle size, indicating that the method of the present invention is applicable to preparing nanoemulsions with different non-ionic surfactants.

[0060] Example 3

[0061] In this example, to investigate whether the method of the present invention is applicable to different organic solvents, the steps are as follows:

[0062] (1) Prepare the oil phase solution and the aqueous phase solution

[0063] Prepare the oil phase solution: Use dichloromethane, bromoethane, and 1-bromopropane as the oil phase solutions respectively.

[0064] Prepare the aqueous solution: Dissolve Pluronic L61 (L61) in deionized water to prepare an L61 aqueous solution with a concentration of 0.2 wt% as the aqueous solution.

[0065] (2) Prepare the nanoemulsion by the spontaneous emulsification method

[0066] Take 4 mL of each of the three aqueous solutions and add them to each glass vial respectively. Then, use a micropipette to add 100 μL of each oil phase solution to each glass vial. After that, shake or stir for 1 min to obtain the nanoemulsion.

[0067] Perform TEM tests on the nanoemulsions prepared in this example and draw the particle size distribution diagrams of the nanoemulsions according to the TEM test results. It is found that when dichloromethane, bromoethane, or 1-bromopropane is used as the oil phase solution to prepare the nanoemulsion in this example, nanoemulsions with uniform particle sizes can be successfully prepared. Figure 3 Figures a - b of this example show the particle size distribution diagram and TEM image of the nanoemulsion prepared with dichloromethane as the oil phase solution. It can be seen from this figure that the prepared nanoemulsion has a narrow particle size distribution range and uniform particle sizes. The above experimental results show that the method described in the present invention is applicable to the preparation of nanoemulsions with different organic solvents.

[0068] Example 4

[0069] In this example, the influence of different combinations of surfactants on the size of the nanoemulsion prepared by the method described in the present invention was investigated. The steps are as follows:

[0070] (1) Prepare the oil phase solution and the aqueous solution

[0071] Prepare the oil phase solution: Use DCM as the oil phase solution.

[0072] Prepare the aqueous solution: Dissolve Pluronic L61 (L61) and Pluronic F127 (F127) in deionized water at different mass ratios (R) to obtain a series of aqueous solutions. The specific compositions of each aqueous solution are as follows:

[0073] When R = 0, the concentration of L61 in the aqueous solution is 0 wt%, and the concentration of F127 is 0.2 wt%;

[0074] When R = 0.1, the concentration of L61 in the aqueous solution is 0.1 wt%, and the concentration of F127 is 1 wt%;

[0075] When R = 0.25, the concentration of L61 in the aqueous solution is 0.05 wt%, and the concentration of F127 is 0.2 wt%;

[0076] When R = 1, the concentration of L61 in the aqueous solution is 0.2 wt%, and the concentration of F127 is 0.2 wt%.

[0077] When R = 2, the concentration of L61 in the aqueous solution is 0.4 wt%, and the concentration of F127 is 0.2 wt%.

[0078] When R = 2.5, the concentration of L61 in the aqueous solution is 0.5 wt%, and the concentration of F127 is 0.2 wt%.

[0079] (2) Preparation of nanoemulsion by spontaneous emulsification method

[0080] Take 4 mL of aqueous solutions with different R values and add them to each glass vial respectively. Then use a micropipette to add 100 μL of oil phase solution to each glass vial, and then shake or stir for 1 min to obtain nanoemulsion.

[0081] When different surfactants are combined in different mass ratios to prepare the aqueous solution in this example, the prepared nanoemulsion has uniform particle size and narrow particle size distribution. Figure 3 Figure d shows the TEM image of the nanoemulsion prepared when R = 0.1. It can be seen from this figure that the particle size of the nanoemulsion is uniform. At the same time, when different surfactants are combined in different mass ratios to prepare the aqueous solution in this example, the particle size of the prepared nanoemulsion varies in the range of 30 nm to 540 nm with the change of the mass ratio of L61 to F127 in the aqueous solution, as shown in Figure 3 Figure c. This shows that the method of the present invention can flexibly control the size of nanoemulsion through the combination of different surfactants.

[0082] Example 5

[0083] In this example, poly(lactic-co-glycolic acid) (PLGA) nanoparticles and PLGA nanoparticles encapsulating curcumin (Cur) are prepared by the method of the present invention. The steps are as follows:

[0084] (1) Preparation of oil phase solution and aqueous solution

[0085] Prepare the oil phase solution: To prepare PLGA nanoparticles, PLGA was added to DCM and stirred thoroughly until completely dissolved to obtain an oil phase solution. In this oil phase solution, the mass ratio of PLGA to DCM was 0.01:1. To prepare PLGA nanoparticles loaded with Cur, using DCM as the organic solvent, PLGA as the functional polymer, and Cur as the functional organic molecule (model drug), PLGA and Cur were added to DCM and stirred thoroughly until completely dissolved to obtain an oil phase solution. In this oil phase solution, the mass ratio of PLGA to DCM was 0.01:1, and the mass ratio of Cur to DCM was 0.01:1.

[0086] Prepare the aqueous phase solution: The surfactant F127 was dissolved in deionized water to prepare an F127 aqueous solution with a concentration of 0.2 wt% as the aqueous phase solution.

[0087] (2) Prepare the nanoemulsion by the spontaneous emulsification method

[0088] Prepare the nanoemulsion containing PLGA: Take 4 mL of the aqueous phase solution and add it to a glass vial. Then, use a micropipette to add 100 μL of the oil phase solution containing PLGA to the glass vial, and then shake or stir for 1 min to obtain a nanoemulsion containing PLGA.

[0089] Prepare the nanoemulsion containing PLGA and Cur: Take 4 mL of the aqueous phase solution and add it to a glass vial. Then, use a micropipette to add 100 μL of the oil phase solution containing both PLGA and Cur to the glass vial, and then shake or stir for 1 min to obtain an oil phase solution containing PLGA and Cur.

[0090] (3) Prepare PLGA nanoparticles and PLGA nanoparticles encapsulating Cur

[0091] Place the nanoemulsion containing PLGA in a water bath at 40 °C and heat for 2 h to completely volatilize the DCM in the emulsion, thus obtaining PLGA nanoparticles.

[0092] Place the nanoemulsion containing PLGA and Cur in a water bath at 40 °C and heat for 2 h to completely volatilize the DCM in the emulsion, thus obtaining PLGA nanoparticles encapsulating Cur.

[0093] The TEM image and particle size distribution diagram of the PLGA nanoparticles prepared in this example are as shown in Figure 4 Figure a. It can be seen from this figure that the PLGA nanoparticles have uniform particle sizes, a narrow particle size distribution range, and good morphology. The fluorescence spectra of the PLGA nanoparticles encapsulating Cur and the individual Cur, and the optical images of the aqueous solution of the PLGA nanoparticles encapsulating Cur are as shown in Figure 4As shown in Figure b, it can be seen from this figure that the fluorescence characteristic peaks of Cur before and after encapsulation are basically unchanged, and the light transmittance of the solution of the encapsulated nanoparticles is good and uniform, indicating that the PLGA nanoparticles encapsulating Cur have good dispersibility.

[0094] Example 6

[0095] In this example, polystyrene-b-polybutadiene-b-polystyrene (PS-b-PB-b-PS) nanovesicles were prepared by the method described in the present invention, and the steps are as follows:

[0096] (1) Prepare an oil phase solution and an aqueous phase solution

[0097] Prepare the oil phase solution: Using DCM as an organic solvent and as a functional polymer, add PS-b-PB-b-PS to DCM and stir well until completely dissolved to obtain an oil phase solution. The concentration of PS-b-PB-b-PS in the oil phase solution is 2 wt%.

[0098] Prepare the aqueous phase solution: Dissolve the surfactant F127 in deionized water to prepare an F127 aqueous solution with a concentration of 0.2 wt% as the aqueous phase solution.

[0099] (2) Prepare a nanoemulsion by the spontaneous emulsification method

[0100] Take 4 mL of the aqueous phase solution and add it to a glass vial. Then use a micropipette to add 100 μL of the oil phase solution to the glass vial, and then shake or stir for 1 min to obtain a nanoemulsion.

[0101] (3) Prepare PS-b-PB-b-PS nanovesicles

[0102] Place the nanoemulsion in a water bath at 40 °C and heat for 2 h to completely volatilize the DCM in the emulsion, thus obtaining PS-b-PB-b-PS nanovesicles.

[0103] The TEM image and particle size distribution diagram of the PS-b-PB-b-PS nanovesicles prepared in this example are as shown in Figure 5 Figures a - b. It can be seen from this figure that the sizes of the PS-b-PB-b-PS nanovesicles are uniform and the size distribution range is narrow. The particle sizes of the PS-b-PB-b-PS nanovesicles are concentrated around 30 nm and the morphology is good.

[0104] Example 7

[0105] In this example, ZIF-8 nanocrystals were prepared by the method described in the present invention, and the steps are as follows:

[0106] (1) Prepare an oil phase solution and an aqueous phase solution

[0107] Prepare the oil-phase solution: Using DCM as the organic solvent and 2-methylimidazole (2-MI) as the functional organic precursor, add 2-MI to DCM and stir well until completely dissolved to obtain the oil-phase solution. The concentration of 2-MI in the oil-phase solution is 0.3 mol / L.

[0108] Prepare the water-phase solution: Dissolve the surfactant F127 and zinc nitrate hexahydrate in deionized water to obtain the water-phase solution. In the water-phase solution, the concentration of F127 is 0.2 wt% and the concentration of zinc nitrate is 0.031 mol / L.

[0109] (2) Prepare the nanoemulsion by the spontaneous emulsification method

[0110] Take 4 mL of the water-phase solution and add it to a glass vial. Then, use a micropipette to add 100 μL of the oil-phase solution to the glass vial. After that, shake or stir for 1 min to obtain the nanoemulsion.

[0111] (3) Prepare ZIF-8 nanocrystals

[0112] Place the nanoemulsion in a water bath at 40 °C and heat for 2 h to completely evaporate the DCM in the emulsion, thus obtaining ZIF-8 nanocrystals.

[0113] The TEM image and particle size distribution diagram of the ZIF-8 nanocrystals prepared in this example are as shown in Figure 5 Figures c - d of. It can be seen from this figure that the size distribution range of the ZIF-8 nanocrystals is narrow, and the particle size of the ZIF-8 nanocrystals is concentrated around 40 nm with good morphology.

[0114] Example 8

[0115] In this example, the method described in the present invention is used to batch-prepare nanoemulsions with uniform size. The steps are as follows:

[0116] (1) Prepare the oil-phase solution and the water-phase solution

[0117] Prepare the oil-phase solution: Use DCM as the oil-phase solution.

[0118] Prepare the water-phase solution: Dissolve the surfactant F127 in deionized water to prepare an F127 aqueous solution with a concentration of 0.2 wt% as the water-phase solution.

[0119] (2) Prepare the nanoemulsion by the spontaneous emulsification method

[0120] Take 1000 mL of the water-phase solution and add it to a beaker. Then, add 50 mL of the oil-phase solution. After that, stir magnetically at a speed of 600 r / min for 1 min to obtain the nanoemulsion.

[0121] Figure 6Figure a in this example is a macroscopic picture during the batch preparation of nanoemulsion. The left picture of this figure is a photo right after the oil-phase solution is added to the water-phase solution, and the right picture of this figure is a photo after the oil-phase solution is added to the water-phase solution and stirred for 1 min. Figure 6 Figure b in this example is a TEM image of the nanoemulsion prepared in batch. Figure 6 Figure c in this example is a particle size distribution diagram of the nanoemulsion prepared in batch. Figure 6 In Figure c, Upper, Middle, and Lower represent the particle size distribution diagrams obtained by TEM testing and statistics of the nanoemulsion taken from the upper, middle, and lower parts of the beaker after the nanoemulsion preparation is completed. Figure 6 It can be seen that the particle sizes of the nanoemulsion prepared in batch in this example are uniform. The particle size distribution ranges of the nanoemulsion in the upper, middle, and lower parts of the beaker have slight differences but are not obvious. The average particle size of the nanoemulsion is about 30 nm, and the particle size distribution of the nanoemulsion is basically the same as that of the nanoemulsion prepared in Example 1 when using 0.2 wt% F127 aqueous solution as the water-phase solution.

[0122] Example 9

[0123] In this example, the PLGA nanoparticles are prepared in batch by the method of the present invention, and the steps are as follows:

[0124] (1) Prepare the oil-phase solution and the water-phase solution

[0125] Prepare the oil-phase solution: Using DCM as the organic solvent and PLGA as the functional polymer, add PLGA to DCM and stir well until completely dissolved to obtain the oil-phase solution. The concentration of PLGA in the oil-phase solution is 1 wt%.

[0126] Prepare the water-phase solution: Dissolve the surfactant F127 in deionized water to prepare a 0.2 wt% F127 aqueous solution as the water-phase solution.

[0127] (2) Prepare the nanoemulsion by the spontaneous emulsification method

[0128] Take 1000 mL of the water-phase solution and add it to a beaker, then add 50 mL of the oil-phase solution, and then magnetically stir at a speed of 600 r / min for 1 min to obtain the nanoemulsion.

[0129] (3) Prepare the PLGA nanoparticles

[0130] Place the nanoemulsion in a water bath at 40 °C and heat for 2 h to completely volatilize the DCM in the nanoemulsion, thus obtaining the PLGA nanoparticles.

[0131] Figure 7Figure a in this example is a macroscopic picture of the batch preparation of PLGA-containing nanoemulsions. The left picture in this figure is a photo just after adding the oil-phase solution to the water-phase solution, and the right picture in this figure is a photo after stirring the oil-phase solution in the water-phase solution for 1 minute. Figure 7 Figure b in this example is a TEM image of the PLGA nanoparticles prepared in batch. Figure 7 Figure c in this example is a particle size distribution diagram of the PLGA nanoparticles prepared in batch. Figure 7 In Figure c, Upper, Middle, and Lower represent the particle size distribution diagrams obtained by TEM testing and statistics of the solutions of PLGA nanoparticles taken from the upper, middle, and lower parts of the beaker after the preparation of the PLGA nanoparticles is completed. Figure 7 It can be seen that the particle sizes of the PLGA nanoparticles prepared in batch in this example are uniform. The particle size distribution ranges of the PLGA nanoparticles in the upper, middle, and lower parts of the beaker are slightly different but not obvious. The average particle size of the PLGA nanoparticles is about 30 nm, and the particle size distribution of the PLGA nanoparticles is basically the same as that of the PLGA nanoparticles prepared in Example 5.

Claims

1. A method for efficiently preparing a nanoemulsion with uniform and controllable size based on spontaneous emulsification, characterized in that: The following steps are involved: (1) Preparation of oil phase solution and water phase solution Prepare the oil phase solution: use an organic solvent as the oil phase solution; or dissolve the functional polymer or / and the functional organic molecule in an organic solvent to form an oil phase solution; the organic solvent is insoluble in water or slightly soluble in water; Prepare an aqueous phase solution: dissolve a nonionic surfactant in water to form an aqueous phase solution; or dissolve a nonionic surfactant and a substance capable of reacting with functional organic molecules in water to form an aqueous phase solution; The concentration of the nonionic surfactant in the aqueous solution is 0.1wt% to 1.1wt%; the nonionic surfactant is soluble in both the oil solution and water, and the solubility of the nonionic surfactant in the oil solution is greater than the solubility of the nonionic surfactant in water; (2) Preparation of nanoemulsion The oil phase solution is added to the water phase solution, the volume ratio of the water phase solution to the oil phase solution is controlled to be at least 20, and the mixture is stirred or shaken for 1 to 5 minutes to obtain a nanoemulsion.

2. The method for efficiently preparing a nanoemulsion with uniform and controllable size based on spontaneous emulsification according to claim 1, characterized in that: The nonionic surfactant includes at least one of Pluronic series surfactants, Tween series surfactants, and Triton X-100.

3. The method for efficiently preparing a nanoemulsion with uniform and controllable size based on spontaneous emulsification according to claim 1 or 2, characterized in that: In step (2), the volume ratio of the aqueous phase solution to the oil phase solution is controlled to be 20:(0.4-1).

4. The method for efficiently preparing a nanoemulsion with uniform and controllable size based on spontaneous emulsification according to claim 1 or 2, characterized in that: When the nanoemulsion is prepared by stirring in step (2), the stirring speed is controlled to be 500-1000 rpm.

5. The method for efficiently preparing a nanoemulsion with uniform and controllable size based on spontaneous emulsification according to claim 1 or 2, characterized in that: The droplet particle size of the nanoemulsion prepared by the method is 20-550nm, and the polydispersity index of the droplet particle size of the nanoemulsion prepared by the method is no more than 0.

2.

6. A method for preparing nanoparticles, characterized in that: The following steps are involved: (1) preparing a nanoemulsion by the method according to any one of claims 1 to 5, wherein the oil phase solution used in preparing the nanoemulsion contains a functional polymer or / and a functional organic molecule; (2) heating the nanoemulsion obtained in step (1) to completely volatilize the organic solvent in the nanoemulsion, thereby obtaining nanoparticles.

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