Low-energy emulsification method capable of controllably preparing dual nano-emulsion with uniform size
By utilizing the spontaneous emulsification mechanism of interfacial mass transfer coupling and phase separation, and taking advantage of the incompatibility of block copolymers and nonionic surfactants, a low-energy-consumption, simple-to-operate, size-uniform dual nanoemulsion was prepared, solving the problems of high energy consumption and size inhomogeneity in the prior art, and realizing the preparation of nanoemulsions with tunable and stable particle size.
Patent Information
- Application Number
- CN202511095131.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-06
- Publication Date
- 2025-10-31
AI Technical Summary
Existing technologies for preparing dual nanoemulsions suffer from problems such as high energy consumption, complex operation, and non-uniform size.
A spontaneous emulsification mechanism involving interfacial mass transfer coupling and phase separation was employed. By preparing oil and aqueous solutions and stirring or shaking them under specific conditions, a dual nanoemulsion was prepared. The incompatibility of block copolymers and nonionic surfactants was used to trigger the phase separation of oil droplets, forming a stable W/O/W or O/W/O structure.
It has achieved the preparation of uniform-sized dual nanoemulsions with low energy consumption and simple operation, narrow particle size distribution, and adjustable particle size, which is suitable for loading functional molecules and is not affected by preparation temperature and pH value.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of nanoemulsion preparation and relates to a low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions. Background Technology
[0002] Dual nanoemulsions are a class of liquid composite systems with unique internal structures, showing broad application prospects in drug delivery, bioimaging, and material templates. The preparation of dual nanoemulsions generally employs a two-step emulsification process. Specifically, a primary emulsion of water-in-oil or oil-in-water is first formed, followed by secondary emulsification to obtain the dual nanoemulsion. Controllable preparation of dual nanoemulsions is crucial for their applications; however, the controllable preparation of dual nanoemulsions with uniform size still faces significant challenges.
[0003] There are three main methods for preparing dual nanoemulsions: a two-step high-energy emulsification method, a high-energy-low-energy two-step emulsification method, and a two-step low-energy emulsification method. The two-step high-energy emulsification method sequentially prepares a primary emulsion (W1 / O or O / W1) and a dual emulsion (W1 / O / W2 or O / W1 / O2) through two high-energy inputs (such as high-pressure homogenization or ultrasound). While this method offers high throughput, it suffers from high energy consumption and the susceptibility of heat-sensitive components (such as proteins and polyphenols) to high shear stress. The high-energy-low-energy two-step emulsification method first prepares a primary emulsion (W1 / O) using a high-energy method, and then disperses the primary emulsion in an external aqueous phase using a low-energy method (such as the phase transition temperature method) to form a dual emulsion. This method suffers from high energy consumption (due to the use of a high-energy emulsification method in the first step) and complex processes. The two-step low-energy emulsification method mainly prepares dual nanoemulsions through two low-energy inputs (such as spontaneous emulsification and phase inversion). This method avoids high-energy input, but still suffers from problems such as complex processes and non-uniform size of the prepared dual nanoemulsions. Therefore, there is an urgent need to develop a method for preparing dual nanoemulsions that is low in energy consumption, simple in process, and uniform in size. Summary of the Invention
[0004] To address the problems of high energy consumption, complex operation, and non-uniform size of prepared dual nanoemulsions in existing technologies, this invention provides a low-energy emulsification method for the controllable preparation of size-uniform dual nanoemulsions based on the spontaneous emulsification mechanism of interfacial mass transfer coupling and phase separation, so as to achieve low-energy, convenient, and controllable preparation of size-uniform dual nanoemulsions.
[0005] To achieve the above-mentioned objectives, the present invention adopts the following two technical solutions, which belong to a general technical concept.
[0006] The first technical solution is as follows:
[0007] A low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions includes the following steps:
[0008] (1) Preparation of oil phase solution and aqueous phase solution
[0009] Preparation of the oil phase solution: Dissolve the block copolymer in organic solvent A, and thoroughly mix the resulting solution with organic solvent B to obtain the oil phase solution; the concentration of the block copolymer in the oil phase solution is 0.1 wt%~1.0 wt%; the block copolymer is insoluble in water, but soluble in organic solvent A and organic solvent B; organic solvent A and organic solvent B are insoluble or slightly soluble in water;
[0010] Preparation of the aqueous solution: The nonionic surfactant is dissolved in water with a pH of 3-11 to form an aqueous solution; the concentration of the nonionic surfactant in the aqueous solution is 0.1 wt%-1.0 wt%; the nonionic surfactant has a higher solubility in organic solvent A than in water, and is insoluble in organic solvent B; the nonionic surfactant is incompatible with the block copolymer.
[0011] (2) Preparation of dual nanoemulsions
[0012] Add the oil phase solution to the aqueous phase solution, controlling the volume ratio of the aqueous phase solution to the oil phase solution to be at least 20, and between 4 and 70. o Stir or shake for 1-5 minutes to obtain the double nanoemulsion.
[0013] The second technical solution is as follows:
[0014] A low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions includes the following steps:
[0015] (1) Preparation of oil phase solution and aqueous phase solution
[0016] Preparation of the oil phase solution: Dissolve the block copolymer and nonionic surfactant in organic solvent A, and thoroughly mix the resulting solution with organic solvent B to obtain the oil phase solution; in the oil phase solution, the concentration of the block copolymer is 0.1 wt%~1.0 wt%, and the concentration of the nonionic surfactant is 0.7 wt%~2.5 wt%; the block copolymer is insoluble in water, but soluble in organic solvent A and organic solvent B; organic solvent A and organic solvent B are insoluble or slightly soluble in water; the solubility of the nonionic surfactant in organic solvent A is greater than its solubility in water, and the nonionic surfactant is insoluble in organic solvent B; the nonionic surfactant is incompatible with the block copolymer;
[0017] Preparation of aqueous solution: Use water with a pH of 3-11 as the aqueous solution;
[0018] (2) Preparation of dual nanoemulsions
[0019] Add the oil phase solution to the aqueous phase solution, controlling the volume ratio of the aqueous phase solution to the oil phase solution to be at least 20, and between 4 and 70. o Stir or shake for 1-5 minutes to obtain the double nanoemulsion.
[0020] In both of the above technical solutions, when preparing the oil phase solution, the organic solvent A only needs to meet three requirements: it must be insoluble or slightly soluble in water, the solubility of the nonionic surfactant in organic solvent A must be greater than its solubility in water, and it must be able to dissolve the block copolymer. There are no other special requirements for organic solvent A. In practical applications, organic solvent A can be selected based on the specific nonionic surfactant and block copolymer used. Dichloromethane is a preferred organic solvent A. Similarly, when preparing the oil phase solution, the organic solvent B only needs to meet three requirements: it must be insoluble or slightly soluble in water, the nonionic surfactant must not dissolve in organic solvent B, and organic solvent B must be able to dissolve the block copolymer. There are no other special requirements for organic solvent B. Ethyl acetate is a preferred organic solvent B.
[0021] In the two technical solutions mentioned above, in step (1), when preparing the oil phase solution, it is preferable to control the volume ratio of organic solvent A to organic solvent B to be 1:(1~2).
[0022] In the two technical solutions mentioned above, feasible nonionic surfactants include the Pluronic series surfactants. Preferably, the nonionic surfactants are Pluronic F68, Pluronic F108, Pluronic F127, Pluronic L61, or Pluronic L64.
[0023] In both of the above technical solutions, when preparing the oil phase solution, the block copolymer used only needs to meet three requirements: the block copolymer is insoluble in water, the block copolymer is soluble in organic solvent A and organic solvent B, and the block copolymer is incompatible with nonionic surfactants. There are no other special requirements for the block copolymer. In practical applications, the block copolymer can be selected based on the specific organic solvents A and B used, as well as the nonionic surfactant. Feasible block copolymers include polystyrene-polybutadiene-polystyrene series block copolymers (PS-b-PB-b-PS) or polystyrene-polyisoprene-polystyrene series block copolymers (PS-b-PI-b-PS), but are not limited to the block copolymers listed above. For polystyrene-polybutadiene-polystyrene block copolymers, the content of polystyrene units in the polystyrene-polybutadiene-polystyrene block copolymers is preferably 23.5 wt% to 33 wt%, and for polystyrene-polyisoprene-polystyrene block copolymers, the content of polystyrene units in the polystyrene-polyisoprene-polystyrene block copolymers is preferably 14 wt% to 22 wt%.
[0024] In the above two technical solutions, step (2) preferably controls the volume ratio of the aqueous phase solution to the oil phase solution to be 20:(0.4~1).
[0025] In the two technical solutions mentioned above, when the double nanoemulsion is prepared by stirring in step (2), it is preferable to control the stirring speed to be 500~1000 rpm.
[0026] In both of the above technical solutions, to prepare a dual nanoemulsion with uniformly sized loaded functional molecules, the oil phase solution and / or aqueous phase solution may also contain functional molecules. Furthermore, to prepare a dual nanoemulsion with uniformly sized loaded different functional molecules, the oil phase solution contains oil-soluble functional molecules, and the aqueous phase solution contains water-soluble functional molecules.
[0027] In the two technical solutions mentioned above, the material of the container used in step (2) when preparing the dual nanoemulsion should meet the requirement that the container does not react with the oil phase solution and the aqueous phase solution. Usually, a glass container can be used to prepare the dual nanoemulsion.
[0028] In both of the above technical solutions, the particle size of the prepared dual nanoemulsions can be adjusted by changing the type of nonionic surfactant in the aqueous solution and the type of block copolymer in the oil solution. For example, this invention has experimentally demonstrated that different particle sizes of dual nanoemulsions can be obtained by using different nonionic surfactants. The average particle size of the dual nanoemulsions prepared by the above two technical solutions is typically between 200 and 1000 nm.
[0029] The polydispersity index of the particle size of the dual nanoemulsions prepared by the above two technical solutions does not exceed 0.3. Further, the polydispersity index of the particle size of the dual nanoemulsions prepared by the above two technical solutions does not exceed 0.25. Even further, the polydispersity index of the particle size of the dual nanoemulsions prepared by the above two technical solutions does not exceed 0.2.
[0030] The principle of the low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions described in this invention is mainly as follows:
[0031] The method described in this invention is based on the spontaneous nanoemulsification mechanism of surfactant cross-interfacial mass transfer coupling phase separation, achieving the controllable preparation of uniformly sized dual nanoemulsions. The nonionic surfactant has a higher solubility in organic solvent A than in water. Simultaneously, the block copolymer is insoluble in water, but soluble in both organic solvent A and organic solvent B. Organic solvents A and B are insoluble or slightly soluble in water. Furthermore, the nonionic surfactant is incompatible with the block copolymer and is insoluble in organic solvent B.
[0032] In the first technical solution, when the oil phase solution comes into contact with the aqueous phase solution, the nonionic surfactant in the aqueous phase solution diffuses from the aqueous phase solution into the organic solvent A of the oil phase solution. This causes the nonionic surfactant to rapidly accumulate in the organic solvent A at the oil-water interface, meaning the concentration of the nonionic surfactant in the organic solvent A at the oil-water interface continuously increases. Because the nonionic surfactant is incompatible with the block copolymer, this triggers phase separation of the oil droplets, causing the block copolymer to transfer into the organic solvent B. During the diffusion process of the nonionic surfactant, some of the aqueous phase is carried into the organic solvent B and stabilized to form internal water droplets. The nonionic surfactant and the block copolymer redistribute on the newly formed interface to stabilize the newly formed W / O. B / O A / W triple emulsion, of which O B The layer is an organic solvent B, O containing block copolymers. A The layer is an organic solvent A containing a nonionic surfactant, in O A Under the action of nonionic surfactants in the layers, the triple emulsion ultimately achieves O2 through backwetting. A The layer was replaced by water, resulting in a W / O ratio. B / W dual nanoemulsion.
[0033] In the second technical solution, when the oil phase solution comes into contact with the aqueous phase solution, the nonionic surfactant itself is enriched in the organic solvent A of the oil droplets. Because the nonionic surfactant is incompatible with the block copolymer, this triggers phase separation of the oil droplets, causing the block copolymer to transfer into the organic solvent B. Some of the aqueous phase also enters the organic solvent B due to the solubility and diffusion of the nonionic surfactant and stabilizes to form internal water droplets. The nonionic surfactant and block copolymer redistribute at the newly formed interface to stabilize the newly formed W / O mixture. B / O A / W triple emulsion, of which O B The layer is an organic solvent B, O containing block copolymers. A The layer is an organic solvent A containing a nonionic surfactant, in O A Under the action of nonionic surfactants in the layers, the triple emulsion ultimately achieves O2 through backwetting. A The layer was replaced by water, resulting in a W / O ratio. B / W dual nanoemulsion.
[0034] Compared with the prior art, the technical solution of the present invention has the following beneficial technical effects:
[0035] 1. This invention provides a low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions. This method, through rational design of the formulations of the oil and aqueous phase solutions and simple operation, induces interfacial instability and achieves spontaneous nanoemulsification without relying on temperature, pH conditions, or chemical reactions as triggering factors, thus preparing size-uniform and controllable dual nanoemulsions. The operation of preparing dual nanoemulsions according to this invention is very simple, using inexpensive and readily available reagents, requiring no complex equipment or large energy consumption. More importantly, the method of this invention achieves rapid preparation of dual nanoemulsions by adding the oil phase solution to the aqueous phase solution and then stirring or shaking for 1-5 minutes. Compared with existing dual nanoemulsion preparation methods, the method of this invention has the advantages of low energy consumption, low equipment requirements, and simple operation. The prepared dual nanoemulsions are stable, have a narrow particle size distribution range, and controllable particle size. Therefore, the method of this invention is not only beneficial for promotion and application in actual production but also helps improve the quality of dual nanoemulsions.
[0036] 2. The method described in this invention can flexibly adjust the particle size of the dual nanoemulsion. For example, by using different nonionic surfactants, block copolymers, or the ratio of hydrophilic / hydrophobic blocks in the block copolymer, the particle size of the dual nanoemulsion can be adjusted. The control method is simple and effective.
[0037] 3. The method described in this invention is unaffected by external environmental factors, such as preparation temperature and pH value of the aqueous solution, in preparing dual nanoemulsions. Experiments have confirmed that the preparation temperature and pH value of the aqueous solution have no significant impact on the preparation effect of the dual nanoemulsions using the method described in this invention. The prepared dual nanoemulsions exhibit good particle size uniformity, and the method also has no significant impact on the particle size distribution range and average particle size.
[0038] 4. The method described in this invention can also be used to prepare dual nanoemulsions loaded with functional molecules. For example, this invention uses an oil phase solution containing the model drug curcumin (Cur) and an aqueous phase solution containing the model drug rhodamine B (RhB) as examples to prepare dual nanoemulsions that simultaneously encapsulate curcumin (Cur) and rhodamine B (RhB), confirming that the method described in this invention can achieve co-encapsulation of water-soluble and oil-soluble functional molecules. Attached Figure Description
[0039] Figure 1 Figures a-b are the particle size distribution and TEM images of the dual nanoemulsion prepared in Example 1. Figure 1 Figures c to d show the particle size distribution and TEM images of the nanoemulsion prepared in Comparative Example 1.
[0040] Figure 2 Figures a-b are the particle size distribution and TEM images of the dual nanoemulsion prepared in Example 2.
[0041] Figure 3 Figures a-b are the particle size distribution and TEM images of the dual nanoemulsion prepared in Example 3.
[0042] Figure 4 Figure a shows the variation of the average particle size and PDI of the dual nanoemulsion prepared in Example 4 with the type of surfactant in the aqueous solution. Figure 4 Figure b shows the variation of the average particle size and PDI of the dual nanoemulsion prepared in Example 5 with the type of block copolymer in the oil phase solution.
[0043] Figure 5 Figures a-b show the average particle size, PDI of the particle size, and particle size distribution of the dual nanoemulsion prepared in Example 6 as a function of temperature.
[0044] Figure 6 Figures a-b show the average particle size and PDI of the dual nanoemulsion prepared in Example 7 as a function of pH of the aqueous solution, as well as the particle size distribution.
[0045] Figure 7Figure a shows the particle size distribution of the dual nanoemulsion (DNEs) prepared in Example 1, the dual nanoemulsion encapsulating Cur (DNEs@Cur) prepared in Comparative Example 2, and the dual nanoemulsion co-encapsulating Cur and RhB (DNEs@Cur-RhB) prepared in Example 8. Figure 7 Figure b shows the fluorescence spectra of RhB, DNEs@Cur prepared in Comparative Example 2, and DNEs@Cur-RhB prepared in Example 8. Detailed Implementation
[0046] The following examples further illustrate the low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions provided by the present invention. It should be noted that the following examples are only for further illustration of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-essential improvements and adjustments made to the present invention by those skilled in the art based on the above description are still within the scope of protection of the present invention.
[0047] Example 1
[0048] In this embodiment, taking the DCM(EA+SBS) / H2O(F127) system as an example, the low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions according to the present invention is illustrated in the following steps:
[0049] (1) Preparation of oil phase solution and aqueous phase solution
[0050] Preparation of the oil phase solution: Dissolve the block copolymer PS-b-PB-b-PS (30 wt% styrene, SBS) with a PS unit content of 30 wt% in dichloromethane (DCM), and then mix the resulting solution with ethyl acetate (EA) at a volume ratio of DCM to EA of 1:1 to obtain the oil phase solution; the concentration of SBS in the oil phase solution is 0.6 wt%.
[0051] Preparation of aqueous solution: Dissolve surfactant Prönnick F127 (F127) in deionized water to obtain an aqueous solution with a concentration of 0.2 wt%.
[0052] (2) Preparation of dual nanoemulsions
[0053] Add 4 mL of the aqueous phase solution to a glass vial, and then add 200 μL of the oil phase solution to the vial using a micropipette. Shake or stir for 1 min to obtain a dual nanoemulsion, denoted as DNEs.
[0054] The particle size distribution of the dual nanoemulsion prepared in this embodiment was tested using dynamic light scattering (DLS), and the dual nanoemulsion was also tested using transmission electron microscopy (TEM). Figure 1 Figure a shows the particle size distribution of the dual nanoemulsion prepared in this embodiment. Figure 1 Figure b is a transmission electron microscope (TEM) image of the dual nanoemulsion prepared in this embodiment. Figure 1 As shown in Figures a to b, the particle size distribution of the dual nanoemulsion prepared in this embodiment exhibits a single-peak distribution, indicating that the size of the dual nanoemulsion is uniform. The average particle size of the dual nanoemulsion is 220 nm. At the same time, the dual nanoemulsion has a good core-shell structure and good morphology.
[0055] Comparative Example 1
[0056] This comparative example is used to compare with Example 1. In preparing the oil phase solution, only DCM was used as the organic solvent; EA was not added. The operation was similar to that in Example 1, and the steps are as follows:
[0057] (1) Preparation of oil phase solution and aqueous phase solution
[0058] Preparation of oil phase solution: The block copolymer PS-b-PB-b-PS (30 wt% styrene, SBS) was dissolved in DCM to obtain an oil phase solution; the concentration of SBS in the oil phase solution was 0.6 wt%.
[0059] Preparation of aqueous solution: Dissolve surfactant F127 in deionized water to obtain aqueous solution. The concentration of F127 in aqueous solution is 0.2 wt%.
[0060] (2) Preparation of nanoemulsions
[0061] Add 4 mL of the aqueous phase solution to a glass vial, and then add 200 μL of the oil phase solution to the vial using a micropipette. Shake or stir for 1 min to obtain the nanoemulsion.
[0062] The nanoemulsion prepared in this comparative example was subjected to particle size distribution testing and transmission electron microscopy (TEM) analysis. Figure 1 Figure c shows the particle size distribution of the dual nanoemulsion prepared in this comparative example. Figure 1 Image d is a transmission electron microscope (TEM) image of the dual nanoemulsion prepared in this comparative example. Figure 1 As shown in Figures c to d, the nanoemulsion prepared in this comparative example is a single emulsion. The particle size distribution of the nanoemulsion exhibits a single-peak distribution, indicating that the nanoemulsion has uniform size and an average particle size of 30 nm.
[0063] As can be seen from Example 1 and Comparative Example 1, without adding EA when preparing the oil phase solution, it is impossible to prepare a dual nanoemulsion under the same operating conditions.
[0064] Example 2
[0065] In this embodiment, the system DCM(EA+SBS) / H2O(F127) (V EA :V DCM Taking (e.g., 2:1) as an example, the low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions according to the present invention is illustrated in the following steps:
[0066] (1) Preparation of oil phase solution and aqueous phase solution
[0067] Preparation of oil phase solution: Dissolve SBS in DCM, and then mix the resulting solution with EA at a volume ratio of DCM to EA of 1:2 to obtain an oil phase solution; the concentration of SBS in the oil phase solution is 0.4 wt%.
[0068] Preparation of aqueous solution: Dissolve surfactant F127 in deionized water to obtain aqueous solution. The concentration of F127 in aqueous solution is 0.2 wt%.
[0069] (2) Preparation of dual nanoemulsions
[0070] Add 4 mL of the aqueous phase solution to a glass vial, and then add 200 μL of the oil phase solution to the vial using a micropipette. Shake or stir for 1 min to obtain a dual nanoemulsion.
[0071] The particle size distribution and transmission electron microscopy (TEM) tests were performed on the dual nanoemulsion prepared in this embodiment. Figure 2 Figure a shows the particle size distribution of the dual nanoemulsion prepared in this embodiment. Figure 2 Figure b is a transmission electron microscope (TEM) image of the dual nanoemulsion prepared in this embodiment. Figure 2 As shown in Figures a to b, the particle size distribution of the dual nanoemulsion prepared in this embodiment is very close to a single-peak distribution, indicating that the size of the dual nanoemulsion prepared by this system is relatively uniform. The average particle size of the dual nanoemulsion is 232 nm. At the same time, the dual nanoemulsion has a good core-shell structure and good morphology.
[0072] Example 3
[0073] In this embodiment, the system DCM(EA+SBS+F127) / H2O(V) is used. EA :V DCM Taking a ratio of 1:1 as an example, the low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions according to the present invention is illustrated in the following steps:
[0074] (1) Preparation of oil phase solution and aqueous phase solution
[0075] Preparation of oil phase solution: Dissolve SBS and surfactant F127 in DCM, and then mix the resulting solution with EA at a volume ratio of 1:1 to obtain oil phase solution; the concentration of SBS in oil phase solution is 0.5 wt%, and the concentration of F127 is 2.5 wt%.
[0076] Preparation of aqueous solution: Deionized water is used as the aqueous solution.
[0077] (2) Preparation of dual nanoemulsions
[0078] Add 4 mL of the aqueous phase solution to a glass vial, and then add 200 μL of the oil phase solution to the vial using a micropipette. Shake or stir for 1 min to obtain a dual nanoemulsion.
[0079] The particle size distribution and transmission electron microscopy (TEM) tests were performed on the dual nanoemulsion prepared in this embodiment. Figure 3 Figure a shows the particle size distribution of the dual nanoemulsion prepared in this embodiment. Figure 3 Figure b is a transmission electron microscope (TEM) image of the dual nanoemulsion prepared in this embodiment. Figure 3 As shown in Figures a to b, the particle size distribution of the dual nanoemulsion prepared in this embodiment exhibits a single-peak distribution, indicating that the size of the dual nanoemulsion prepared by this system is uniform. The average particle size of the dual nanoemulsion is 223 nm. At the same time, the dual nanoemulsion has a good core-shell structure and regular morphology.
[0080] Example 4
[0081] In this embodiment, Pluronic F68 (F68), Pluronic F108 (F108), Pluronic F127 (F127), Pluronic L64 (L64), and Pluronic L61 (L61) were used as surfactants to investigate the effect of different types of nonionic surfactants on the dual nanoemulsions prepared by the method of the present invention. The steps are as follows:
[0082] (1) Preparation of oil phase solution and aqueous phase solution
[0083] Preparation of oil phase solution: Dissolve SBS in DCM, and then mix the resulting solution thoroughly with EA at a volume ratio of DCM to EA of 1:1 to obtain the oil phase solution; the concentration of SBS in the oil phase solution is 0.5 wt%.
[0084] Preparation of aqueous solutions: Different nonionic surfactants (F68, F108, F127, L64, L61) were dissolved in deionized water to obtain aqueous solutions; the concentration of nonionic surfactants in each aqueous solution was 0.2 wt%.
[0085] (2) Preparation of dual nanoemulsions
[0086] Take 4 mL of each different aqueous phase solution and add it to each glass vial. Then add 200 μL of oil phase solution to each glass vial using a micropipette. Shake or stir for 1 min to obtain a dual nanoemulsion.
[0087] The particle size distribution of each dual nanoemulsion prepared in this embodiment was tested and the polydispersity index (PDI) of the particle size was calculated. Figure 4 Figure a shows the variation of the average particle size and PDI of the dual nanoemulsion prepared in this embodiment with the type of surfactant in the aqueous solution. Figure 4 As shown in Figure a, when F68, F108, F127, L64, or L61 are used as surfactants, the PDI of the particle size of the dual nanoemulsions prepared in this embodiment is less than 0.24, indicating that the prepared dual nanoemulsions have a narrow particle size distribution range and uniform particle size. With the change of nonionic surfactant, the particle size of the dual nanoemulsions varies, increasing from 207 nm to 674 nm. In particular, when L64 and L61 are used as surfactants, the particle size of the prepared dual nanoemulsions is significantly larger.
[0088] The above experimental results demonstrate that the method described in this invention is applicable to the preparation of dual nanoemulsions using different nonionic surfactants, and that the particle size of the dual nanoemulsions can be flexibly controlled by adjusting the type of surfactant.
[0089] Example 5
[0090] In this embodiment, PS-b-PB-b-PS (30 wt% styrene, SBS) with a PS unit content of 30 wt%, PS-b-PB-b-PS (23.5 wt% styrene, SBS-1) with a PS unit content of 23.5 wt%, PS-b-PB-b-PS (approximately 29 wt% PS block content, SBS-2) with a viscosity of 500 cps, PS-b-PB-b-PS (approximately 33 wt% PS block content, SBS-3) with a viscosity of 3000 cps, and PS-b-PI-b-PS (22 wt% styrene, SIS) with a PS block content of 22 wt% were used as block copolymers to investigate the effect of different types of block copolymers on the dual nanoemulsion prepared by the method of the present invention. The steps are as follows:
[0091] (1) Preparation of oil phase solution and aqueous phase solution
[0092] Preparation of oil phase solutions: The block copolymers (SBS, SBS-1, SBS-2, SBS-3, SIS) were dissolved in DCM respectively. Then, the resulting solutions were thoroughly mixed with EA at a volume ratio of 1:1 to obtain oil phase solutions. The concentration of the block copolymers in each oil phase solution was 0.4 wt%.
[0093] Preparation of aqueous solution: Dissolve surfactant F127 in deionized water to obtain aqueous solution; the concentration of F127 in aqueous solution is 0.2 wt%.
[0094] (2) Preparation of dual nanoemulsions by spontaneous emulsification method
[0095] Take 4 mL of the aqueous phase solution and add it to each glass vial. Then, use a micropipette to add 200 μL of different oil phase solutions to each glass vial. Shake or stir for 1 min to obtain a dual nanoemulsion.
[0096] The particle size distribution of each dual nanoemulsion prepared in this embodiment was tested and the polydispersity index (PDI) of the particle size was calculated. Figure 4 Figure b shows the variation of the average particle size and PDI of the dual nanoemulsion prepared in this embodiment with the type of block copolymer in the oil phase solution. Figure 4 As shown in Figure b, when SBS, SBS-1, SBS-2, SBS-3, and SIS are used as block copolymers, the PDI of the dual nanoemulsions prepared in this embodiment is less than 0.3, indicating that the prepared dual nanoemulsions have a narrow particle size distribution range and uniform particle size. With the change of the type of block copolymer and the ratio of hydrophilic / hydrophobic blocks, the particle size of the dual nanoemulsions varies.
[0097] The above experimental results demonstrate that the method described in this invention is applicable to the preparation of dual nanoemulsions using different block copolymers, and the particle size of the dual nanoemulsions can be adjusted by changing the type of block copolymer and the ratio of its hydrophilic / hydrophobic blocks.
[0098] Example 6
[0099] In this embodiment, the effect of temperature on the dual nanoemulsion prepared by the method of the present invention is investigated, and the steps are as follows:
[0100] (1) Preparation of oil phase solution and aqueous phase solution
[0101] Preparation of oil phase solution: Dissolve SBS in DCM, and then mix the resulting solution thoroughly with EA at a volume ratio of DCM to EA of 1:1 to obtain the oil phase solution; the concentration of SBS in the oil phase solution is 0.5 wt%.
[0102] Preparation of aqueous solution: Dissolve surfactant F127 in deionized water to obtain aqueous solution; the concentration of F127 in aqueous solution is 0.2 wt%.
[0103] (2) Preparation of dual nanoemulsions
[0104] Add 4 mL of the aqueous phase solution to each glass vial, and then add 200 μL of the oil phase solution to each glass vial using a micropipette. Shake or stir for 1 min to obtain the dual nanoemulsion.
[0105] Seal each glass vial and place each double nanoemulsion separately in 4 o C, 25 o C, 37 o C, 50 o C and 70 o The particles were kept in a water bath at C for 2 hours, and then the particle size distribution was tested and the polydispersity index (PDI) of the particles was calculated. Figure 5 Figure a shows the changes in average particle size and PDI of the dual nanoemulsion prepared in this embodiment as a function of temperature. Figure 5 Figure b is the particle size distribution diagram of the dual nanoemulsion prepared in this embodiment. Figure 5 It can be seen that the dual nanoemulsion prepared in this embodiment has a temperature range of 4~37°C. o After being kept in a water bath at temperature C for 2 hours, the average particle size of the dual nanoemulsion remained essentially unchanged. However, when the water bath temperature was increased to 50-70°C... o After temperature C, the average particle size of the dual nanoemulsion increased slightly. However, after maintaining it under different water bath conditions for 2 hours, the PDI of the particle size of the dual nanoemulsion was less than 0.24. This indicates that temperature does not significantly affect the uniformity of the particle size of the dual nanoemulsion prepared by the method of the present invention.
[0106] The above experimental results demonstrate that the method described in this invention can operate at temperatures ranging from 4 to 70°C. o Dual nanoemulsions were prepared within the range of C.
[0107] Example 7
[0108] In this embodiment, the effect of the pH value of the aqueous solution on the dual nanoemulsion prepared by the method of the present invention was investigated, and the steps are as follows:
[0109] (1) Preparation of oil phase solution and aqueous phase solution
[0110] Preparation of oil phase solution: Dissolve SBS in DCM, and then mix the resulting solution thoroughly with EA at a volume ratio of DCM to EA of 1:1 to obtain the oil phase solution; the concentration of SBS in the oil phase solution is 0.5 wt%.
[0111] Preparation of aqueous solutions: The pH of deionized water was adjusted to 3, 5, 7, 9 and 11 respectively with hydrochloric acid solution or sodium hydroxide solution. Surfactant F127 was dissolved in deionized water with different pH values to obtain aqueous solutions. The concentration of F127 in each aqueous solution was 0.2 wt%.
[0112] (2) Preparation of dual nanoemulsions
[0113] Take 4 mL of aqueous solution with different pH values and add it to each glass vial. Then, add 200 μL of different oil solution to each glass vial using a micropipette. Shake or stir for 1 min to obtain a dual nanoemulsion.
[0114] The particle size distribution of each dual nanoemulsion prepared in this embodiment was tested and the polydispersity index (PDI) of the particle size was calculated. Figure 6 Figure a shows the variation of the average particle size and PDI of the dual nanoemulsion prepared in this embodiment with the pH value of the aqueous solution. Figure 6 Figure b is the particle size distribution diagram of the dual nanoemulsion prepared in this embodiment. Figure 6 It can be seen that the pH value of the aqueous solution has a certain influence on the particle size distribution range of the dual nanoemulsion. The particle size distribution (PDI) of the dual nanoemulsion prepared with pH=7 in the aqueous solution is the smallest, with PDI less than 0.1. However, when the pH of the aqueous solution is in the range of 3 to 11, the PDI of the prepared dual nanoemulsion is less than 0.24, indicating that the particle size of the nanoemulsion still has good uniformity.
[0115] The above experimental results demonstrate that the method described in this invention is applicable to the preparation of dual nanoemulsions using aqueous solutions with different pH values (pH=3~11).
[0116] Example 8
[0117] In this embodiment, a dual nanoemulsion encapsulating the model drugs curcumin (Cur) and rhodamine B (RhB) is prepared using the method described in this invention. The steps are as follows:
[0118] (1) Preparation of oil phase solution and aqueous phase solution
[0119] Preparation of oil phase solution: In order to prepare dual nanoemulsion loaded with Cur and RhB, Cur was used as a model drug. Cur and SBS were added to DCM and stirred until completely dissolved. Then, the resulting solution was thoroughly mixed with EA at a volume ratio of 1:1 to obtain an oil phase solution. The concentration of SBS and Cur in the oil phase solution was 0.6 wt%.
[0120] Preparation of aqueous solution: Dissolve the surfactant F127 labeled with RhB (RhB-F127) in deionized water to obtain an aqueous solution; the concentration of RhB-F127 in the aqueous solution is 0.2 wt%.
[0121] (2) Preparation of dual nanoemulsions
[0122] Add 4 mL of the aqueous phase solution to a glass vial, and then add 200 μL of the oil phase solution to the vial using a micropipette. Shake or stir for 1 min to obtain a dual nanoemulsion that co-encapsulates Cur and RhB, denoted as DNEs@Cur-RhB.
[0123] Comparative Example 2
[0124] In this comparative example, a dual nanoemulsion for encapsulating the model drug Cur was prepared using the method described in this invention, and the steps are as follows:
[0125] (1) Preparation of oil phase solution and aqueous phase solution
[0126] Preparation of oil phase solution: Add Cur and SBS to DCM and stir thoroughly until completely dissolved. Then, mix the resulting solution with EA at a volume ratio of 1:1 to obtain the oil phase solution. The concentration of SBS and Cur in the oil phase solution is 0.6 wt.
[0127] Preparation of aqueous solution: Dissolve surfactant F127 in deionized water to obtain aqueous solution; the concentration of F127 in aqueous solution is 0.2 wt%.
[0128] (2) Preparation of dual nanoemulsions
[0129] Add 4 mL of the aqueous phase solution to a glass vial, and then add 200 μL of the oil phase solution to the vial using a micropipette. Shake or stir for 1 min to obtain a dual nanoemulsion that co-encapsulates Cur, denoted as DNEs@Cur.
[0130] The particle size distribution diagrams of the dual nanoemulsions (DNEs) prepared in Example 1, the dual nanoemulsions encapsulating Cur (DNEs@Cur) prepared in Comparative Example 2, and the dual nanoemulsions co-encapsulating Cur and RhB (DNEs@Cur-RhB) prepared in Example 8 are shown below. Figure 7 As shown in Figure a, it can be seen that DNEs, DNEs@Cur, and DNEs@Cur-RhB have uniform particle size and narrow particle size distribution range, with particle sizes of 226 nm, 228 nm, and 264 nm, respectively. This indicates that drug encapsulation does not significantly affect the particle size uniformity of the dual nanoemulsions. Fluorescence spectroscopy tests were performed on RhB, DNEs@Cur, and DNEs@Cur-RhB, and the results are as follows... Figure 7 As shown in Figure b, the fluorescence characteristic peaks of Cur and RhB remain basically unchanged before and after encapsulation, indicating that DNEs@Cur-RhB successfully encapsulated Cur and RhB, and the dual nanoemulsion after drug encapsulation has good fluorescence properties.
[0131] Example 9
[0132] In this embodiment, a low-energy emulsification method for preparing controllable size-uniform dual nanoemulsions is provided. The operation is basically the same as in Example 1, except that: in the oil phase solution of step (1), the concentration of SBS is 0.1 wt%; in the aqueous phase solution of step (1), the concentration of F127 is 0.1 wt%; in step (2), the amount of aqueous phase solution used is 4 mL and the amount of oil phase solution used is 80 μL.
[0133] The particle size distribution of the dual nanoemulsion prepared in this embodiment was tested. The results showed that the particle size distribution of the dual nanoemulsion prepared in this embodiment exhibited a single-peak distribution, indicating that the size of the dual nanoemulsion was uniform.
[0134] Example 10
[0135] In this embodiment, a low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions is provided. The operation is basically the same as in Example 1, except that: SBS in step (1) is replaced with PS-b-PI-b-PS (14 wt% styrene, SIS-1) with a PS block content of 14 wt%. In the oil phase solution of step (1), the concentration of SIS-1 is 1.0 wt%; in the aqueous phase solution of step (1), the concentration of F127 is 1.0 wt%.
[0136] The particle size distribution of the dual nanoemulsion prepared in this embodiment was tested. The results showed that the particle size distribution of the dual nanoemulsion prepared in this embodiment exhibited a single-peak distribution, indicating that the size of the dual nanoemulsion was uniform.
[0137] Example 11
[0138] In this embodiment, a low-energy emulsification method for preparing controllable size-uniform dual nanoemulsions is provided. The operation is basically the same as in Example 3, except that the concentration of SBS in the oil phase solution of step (1) is 0.1 wt% and the concentration of F127 is 0.7 wt%.
[0139] The particle size distribution of the dual nanoemulsion prepared in this embodiment was tested. The results showed that the particle size distribution of the dual nanoemulsion prepared in this embodiment exhibited a single-peak distribution, indicating that the size of the dual nanoemulsion was uniform.
[0140] Example 12
[0141] In this embodiment, a low-energy emulsification method for preparing controllable size-uniform dual nanoemulsions is provided. The operation is basically the same as in Example 3, except that: in the oil phase solution of step (1), the concentration of SBS is 1.0 wt% and the concentration of F127 is 2.0 wt%; in step (2), the amount of aqueous phase solution is 4 mL and the amount of oil phase solution is 80 μL.
[0142] The particle size distribution of the dual nanoemulsion prepared in this embodiment was tested. The results showed that the particle size distribution of the dual nanoemulsion prepared in this embodiment exhibited a single-peak distribution, indicating that the size of the dual nanoemulsion was uniform.
Claims
1. A low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions, characterized in that, Includes the following steps: (1) Preparation of oil phase solution and aqueous phase solution Preparation of the oil phase solution: Dissolve the block copolymer in organic solvent A, and thoroughly mix the resulting solution with organic solvent B to obtain the oil phase solution; the concentration of the block copolymer in the oil phase solution is 0.1 wt%~1.0 wt%; the block copolymer is insoluble in water, but soluble in organic solvent A and organic solvent B; organic solvent A and organic solvent B are insoluble or slightly soluble in water; Preparation of the aqueous solution: The nonionic surfactant is dissolved in water with a pH of 3-11 to form an aqueous solution; the concentration of the nonionic surfactant in the aqueous solution is 0.1 wt%-1.0 wt%; the nonionic surfactant has a higher solubility in organic solvent A than in water, and is insoluble in organic solvent B; the nonionic surfactant is incompatible with the block copolymer. (2) Preparation of dual nanoemulsions Add the oil phase solution to the aqueous phase solution, controlling the volume ratio of the aqueous phase solution to the oil phase solution to be at least 20, and between 4 and 70. o Stir or shake for 1-5 minutes to obtain the double nanoemulsion.
2. A low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions, characterized in that, Includes the following steps: (1) Preparation of oil phase solution and aqueous phase solution Preparation of the oil phase solution: Dissolve the block copolymer and nonionic surfactant in organic solvent A, and thoroughly mix the resulting solution with organic solvent B to obtain the oil phase solution; in the oil phase solution, the concentration of the block copolymer is 0.1 wt%~1.0 wt%, and the concentration of the nonionic surfactant is 0.7 wt%~2.5 wt%; the block copolymer is insoluble in water, but soluble in organic solvent A and organic solvent B; organic solvent A and organic solvent B are insoluble or slightly soluble in water; the solubility of the nonionic surfactant in organic solvent A is greater than its solubility in water, and the nonionic surfactant is insoluble in organic solvent B; the nonionic surfactant is incompatible with the block copolymer; Preparation of aqueous solution: Use water with a pH of 3-11 as the aqueous solution; (2) Preparation of dual nanoemulsions Add the oil phase solution to the aqueous phase solution, controlling the volume ratio of the aqueous phase solution to the oil phase solution to be at least 20, and between 4 and 70. o Stir or shake for 1-5 minutes to obtain the double nanoemulsion.
3. The low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions according to claim 1 or 2, characterized in that, In step (1), when preparing the oil phase solution, the volume ratio of organic solvent A to organic solvent B is 1:(1~2).
4. The low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions according to claim 3, characterized in that, Organic solvent A includes dichloromethane, and organic solvent B includes ethyl acetate.
5. The low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions according to claim 1 or 2, characterized in that, The nonionic surfactants include Pluronic F68, Pluronic F108, Pluronic F127, Pluronic L61, or Pluronic L64.
6. The low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions according to claim 1 or 2, characterized in that, The block copolymers include polystyrene-polybutadiene-polystyrene block copolymers or polystyrene-polyisoprene-polystyrene block copolymers.
7. The low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions according to claim 6, characterized in that, In polystyrene-polybutadiene-polystyrene block copolymers, the content of polystyrene units is 23.5 wt%~33 wt%; in polystyrene-polyisoprene-polystyrene block copolymers, the content of polystyrene units is 14 wt%~22 wt%.
8. The low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions 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).
9. The low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions according to claim 1 or 2, characterized in that, The oil phase solution contains oil-soluble functional molecules, and the aqueous phase solution contains water-soluble functional molecules.
10. The low-energy emulsification method for controllably preparing size-uniform dual nanoemulsions according to claim 1 or 2, characterized in that, The polydispersity index of the particle size of the dual nanoemulsion prepared in step (2) does not exceed 0.3.