A eutectic solution, a preparation method and application thereof

Abstract

The application provides a eutectic solution, a preparation method and application, and relates to the technical field of block polymers. The eutectic solution comprises a liquid amphiphilic block copolymer containing a hydrogen bond acceptor and raw material components of an active substance and / or a polyol hydrogen bond donor. The liquid amphiphilic block copolymer has a high loading rate for the active substance, good release performance, and the eutectic solution formed by the liquid amphiphilic block copolymer and the polyol has good moisturizing effect.

Description

Technical Field

[0001] This invention belongs to the field of block polymer technology and relates to a eutectic solution, its preparation method, and its application. Background Technology

[0002] Eutectic solvents are high-entropy solutions formed by the hydrogen bond interactions between hydrogen bond donors and acceptors. The resulting hydrogen bond network interferes with the crystallization ability of the original compound (hydrogen bond donors and / or acceptors), maintaining a liquid state at room temperature. Eutectic solvents have shown great application potential in the solubilization and stabilization of water-insoluble active substances, and have promising applications in personal care products, food, and pharmaceuticals.

[0003] Chinese patent CN119925268A discloses a eutectic solvent that promotes ultra-high solubility of curcumin. Hydrogen bond donors include citric acid, ethylene glycol, glycerol, polyethylene glycol, urea, nicotinamide, mannose, trehalose, and glucose, while hydrogen bond acceptors include choline chloride, betaine, mannose, and sorbitol. Water and alcohols are also added as other components to form the eutectic solvent. Chinese patent CN119818988A discloses a natural eutectic solvent prepared by uniformly mixing D-fructose, glycerol, xylitol, and deionized water. Chinese patent CN117481984A discloses a supramolecular bisabolol eutectic solvent, which is composed of bisabolol and ligands. The ligands include cyclohexanol compounds, phenolic compounds, carboxylic acid compounds, non-cyclic monohydric alcohols, polyols, etc. Bisabolol is modified by supramolecular eutectic solvent to obtain bisabolol-based eutectic solvents. The active ingredient is delivered using liposome encapsulation technology and supramolecular eutectic solvent technology, which improves the stability and irritation of the active ingredient, promotes transdermal absorption, sustained release and targeting effects.

[0004] However, existing eutectic solvents used for loading active substances still have some shortcomings. For example, the composition of eutectic solvents is relatively complex, and heating is required when loading active substances with eutectic solvents, which can have adverse effects on some heat-sensitive active substances.

[0005] Therefore, existing eutectic solvents for loading active substances urgently need improvement. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a eutectic solution, its preparation method, and its application.

[0007] The technical solution of the present invention is as follows:

[0008] A eutectic solution comprising a raw material component including an amphiphilic block copolymer and an active substance and / or a polyol; The viscosity of the amphiphilic block copolymer at 25°C does not exceed 10000 mPa·s; The number of hydrogen bond donors contained in the active substance and the polyol is not less than two. The amphiphilic block copolymer contains a number of oxygen atoms.

[0009] Preferably, the amphiphilic block copolymer has the structure shown in formulas (1), (2), (3) and / or (4). AbB(1); AbBbA(2); BA3(3); BbAbB(4); Where A is a hydrophobic segment and B is a hydrophilic segment; The hydrophilic segment contains several oxygen atoms.

[0010] More preferably, the hydrophilic segment is selected from polyethylene glycol segments and / or glycerol polyethylene glycol segments; The hydrophobic segment is biodegradable; The hydrophobic segment is selected from one or a combination of two or more of the following: polylactic acid segment, polycaprolactone segment, polyhydroxybutyrate segment, polyhydroxyacetic acid segment, polydioxane segment, polytrimethylene carbonate segment, polybutylene succinate segment, polysaccharide segment, polysebacate segment, polybutylene adipate-butylene terephthalate copolymer segment, and polyorthoester segment.

[0011] More preferably, the average degree of polymerization of the hydrophobic segment accounts for 2-60% of the average degree of polymerization of the amphiphilic block copolymer.

[0012] Preferably, the active substance is selected from one or a combination of two or more of the following: palmitoyl pentapeptide-4, palmitoyl tetrapeptide-7, blue ketone peptide, palmitoyl tripeptide-1, ganoderic triterpenes, ginsenosides, artemisinin, ferulic acid, astaxanthin, tea polyphenols, vitamin E, resveratrol, glycyrrhizin, rutin, quercetin, caffeine, penicillin G, omeprazole, imatinib, berberine, and quinine.

[0013] Preferably, the polyol is selected from one or a combination of two or more of ethylene glycol, glycerol, butanediol, pentanediol, 1,2,5-pentanediol, dipentaerythritol, and pentaerythritol.

[0014] Preferably, the weight ratio of the amphiphilic block copolymer to the active substance is 10:0.0001-3; The weight ratio of the amphiphilic block copolymer to the polyol is 1:0.5-10.

[0015] A method for preparing a eutectic solution according to any of the above embodiments involves mixing the raw material components comprising the amphiphilic block copolymer and the active substance and / or the polyol and stirring until transparent to obtain the eutectic solution.

[0016] The application of the eutectic solution described in any of the above embodiments is used in the preparation of personal care products or pharmaceuticals.

[0017] The beneficial effects of this invention are: (1) The present invention found that amphiphilic block copolymers that are in a liquid state at room temperature (the degree of polymerization of liquid amphiphilic block copolymers is not high) can act as hydrogen bond acceptors, and can directly form more and stronger hydrogen bond interactions with active substances and / or polyols containing hydrogen bond donors, and convert solid active substances into liquid state, forming eutectic solutions, and improving the solubility of active substances in water, or improving the solubility of liquid active substances with poor water solubility in water, with obvious solubilization effect, or the combination of amphiphilic block copolymers and polyols can further improve the moisturizing effect.

[0018] (2) The eutectic solution of the present invention can be obtained uniformly and stably without the addition of solvent components such as water and ethanol. Moreover, the amphiphilic block copolymer and active material can be well mixed by stirring at room temperature. The process is simple, does not require complicated equipment, and can avoid the adverse effects of heating on some active materials with poor heat resistance. Attached Figure Description

[0019] Figure 1 This is a comparison of the appearance of the eutectic solution in Example 1 and the appearance of the resveratrol aqueous dispersion.

[0020] Figure 2 This is a TEM image of the nanoaggregates in the aqueous solution of the eutectic solution in Example 1.

[0021] Figure 3 The image shows the appearance of the eutectic solution in Example 4. Detailed Implementation

[0022] The technical solution of the present invention will be further explained and described below through specific embodiments.

[0023] On the one hand, the present invention proposes a eutectic solution composed of raw material components comprising amphiphilic block copolymers and active substances and / or polyols; The viscosity of the amphiphilic block copolymer at 25°C does not exceed 10000 mPa·s; The active substance and the polyol each contain at least two hydrogen bond donors. Amphiphilic block copolymers contain several oxygen atoms.

[0024] In this invention, the presence of hydrogen bond donors in the active substance and polyol refers to the presence of a group (i.e., an active hydrogen group) in the molecule of the active substance or polyol that can provide a hydrogen atom, and this group contains a highly electronegative atom (such as O, N, S) directly bonded to the hydrogen atom. The group can be -OH, -SH, -NH2, -NH-, -SO3H, -CONH-, -COOH, etc. These groups can form hydrogen bonds with electronegative atoms of other substances (such as O, N, F). For example, the group containing a hydrogen atom in a polyol is a hydroxyl group.

[0025] This invention discovers that amphiphilic block copolymers that are liquid at room temperature (i.e., amphiphilic block copolymers with low degree of polymerization and containing several oxygen atoms, which can act as hydrogen bond acceptors) and active substances containing hydrogen bond donors can directly form a homogeneous and transparent eutectic liquid without the need to add solvent components such as water, ethanol, or isopropanol. Specifically, the eutectic solution formed in this invention has two conditions: (1) the amphiphilic block copolymer is liquid at room temperature; (2) the amphiphilic block copolymer contains hydrogen bond acceptors, and the active substance and / or polyol each contain hydrogen bond donors. When the active substance containing hydrogen bond donors has low solubility in water, the solubility of the active substance in water can be increased by forming a eutectic solution. Therefore, the eutectic solution of this invention has a good solubilizing effect on active substances with low solubility. For polyols as hydrogen bond donors, this invention discovers that after the amphiphilic block copolymer and polyol, which are liquid at room temperature, form a eutectic solution, the moisturizing effect of the polyol can be improved, achieving long-lasting moisturizing.

[0026] The active material and the polyol contain at least two hydrogen bond donors, meaning at least two active hydrogen groups. This allows them to form more hydrogen bonds with the amphiphilic block copolymer. Through the interaction between hydrogen bond donors and acceptors, the eutectic solution exhibits better performance, such as being able to load more active materials and form a uniform and transparent state, or extending the moisturizing time of the polyol and providing a long-lasting moisturizing effect.

[0027] For the above-mentioned active material and amphiphilic block copolymer to form a eutectic solution, the eutectic solution can be obtained by stirring at room temperature; when the active material has a high melting point and / or dissolves slowly, the active material with good heat resistance can also be appropriately heated to promote the rapid mixing of the two raw material components.

[0028] In this invention, there are no particular limitations on viscosity testing; for example, an NDJ-5S rotational viscometer can be used. There are also no particular limitations on the viscosity of the amphiphilic block copolymer at 25°C; examples include 10000 mPa·s, 9000 mPa·s, 8000 mPa·s, 6000 mPa·s, 5000 mPa·s, 3000 mPa·s, 2000 mPa·s, 1000 mPa·s, 800 mPa·s, 600 mPa·s, 500 mPa·s, 300 mPa·s, and 200 mPa·s.

[0029] In some embodiments, the amphiphilic block copolymer has the structure shown in formulas (1), (2), (3) and / or (4). AbB(1); AbBbA(2); BA3(3); BbAbB(4); Where A is a hydrophobic segment and B is a hydrophilic segment; The hydrophilic segment contains several oxygen atoms as described above.

[0030] In the structures shown in equations (1), (2), (3), and (4) above, b represents a block. For example, AbB represents a diblock copolymer composed of A and B segments; AbBbA represents a triblock copolymer composed of A and B segments, with the segment order being A, B, A; BA3 represents a branched structure formed by grafting three A segments onto one B segment at the center. The hydrophilic segments contain multiple oxygen atoms, which can form numerous hydrogen bonds with active substances and / or polyols.

[0031] In some embodiments, the hydrophilic segment is selected from polyethylene glycol (PEG) segments and / or glycerol PEG segments. For PEG segments, for example, the number average molecular weight can be 200 g / mol (denoted as PEG-200, and so on), 400 g / mol, 600 g / mol, 800 g / mol, 1000 g / mol, 2000 g / mol, 4000 g / mol, 6000 g / mol, etc. Glycerol PEG, also known as polyethylene glycol triol, contains three PEG branched structures and is obtained by ring-opening ethylene oxide reaction using glycerol as an initiator. For example, the average degree of polymerization (DP) of each PEG branched structure can be 3-20, that is, the average number of vinyl oxygen atoms in each PEG branched structure is 3-20. Both PEG segments and / or glycerol PEG segments contain several oxygen atoms, making them suitable as hydrogen bond acceptors.

[0032] The hydrophobic segments are biodegradable; The hydrophobic segment is selected from one or a combination of two or more of the following: polylactic acid (PLLA or PDLA) segments, polycaprolactone (PCL) segments, polyhydroxybutyrate (PHB) segments, polyhydroxyacetic acid (PGA) segments, polydioxane (PDS) segments, polytrimethylene carbonate (PTMC) segments, polybutylene succinate (PBS) segments, polysaccharide sebacate (PSPA) segments, polybutylene adipate-butylene terephthalate copolymer (PBAT) segments, and polyorthoester (POE) segments.

[0033] In this invention, the hydrophobic segments may or may not be biodegradable. When the hydrophobic segments are biodegradable, they exhibit good biocompatibility. Furthermore, as the hydrophobic segments degrade, the eutectic solution gradually dissociates and releases the active substances and / or polyols, thereby achieving the loading and release of high-concentration active substances or prolonging the moisturizing effect of the polyols, providing long-lasting hydration.

[0034] There are no particular limitations on the preparation methods of the above-mentioned amphiphilic block copolymers, which are well known to those skilled in the art. For example, living polymerization methods, such as living cationic polymerization, can be used, with polyethylene glycol, polyethylene glycol monomethyl ether, or glycerol polyethylene glycol as initiators, catalyzing the ring-opening polymerization of cyclic monomers such as lactide and caprolactone under the catalysis of a cationic catalyst (such as stannous octoate). The above-mentioned amphiphilic block copolymers can also be obtained by direct polymer reaction methods, such as by the addition reaction of isocyanate-double-terminated polyethylene glycol with a single-hydroxyl-terminated polymer, or by the addition reaction of polyethylene glycol or glycerol polyethylene glycol with a single-isocyanate-terminated polymer. Specifically, taking PCL-PEG-PCL triblock copolymer as an example, the preparation method can be as follows: ε-caprolactone monomer is purified by vacuum distillation at 100-130℃; polyethylene glycol (e.g., PEG-200, PEG-600) is vacuum-treated at 80-100℃ for 1-5 hours, then heated to 130-170℃, and stannous octoate and ε-caprolactone monomer are added. The reaction is carried out for 1-48 hours, cooled, and dissolved in chloroform. The product is then precipitated in a large amount of diethyl ether at 0-10℃. The product is freeze-dried to obtain the triblock copolymer. The molecular weight of the PCL segments can be adjusted according to the molar amounts of caprolactone monomer and PEG.

[0035] For example, the number-average molecular weight of hydrophobic segments can be 300-2000 g / mol.

[0036] In some embodiments, the average degree of polymerization of the hydrophobic segment accounts for 2-60% of the average degree of polymerization of the amphiphilic block copolymer. For example, if the amphiphilic block copolymer is AbBbA, the hydrophilic segment is PEG with an average degree of polymerization of 12, and the hydrophobic segment is PCL with an average degree of polymerization of 3, then the average degree of polymerization of the hydrophobic segment accounts for (3+3) / (12+3+3)=33%. For example, the average degree of polymerization of the hydrophobic segment can be any value or any value between 2%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, etc., without particular limitation. When the average degree of polymerization of the hydrophobic segment accounts for a low percentage of the average degree of polymerization of the amphiphilic block copolymer, such as 2-10%, it indicates that the average degree of polymerization of the hydrophobic segment in the amphiphilic block copolymer is low; for example, the average degree of polymerization of the hydrophobic segment can be 1-3. Furthermore, the average degree of polymerization of the hydrophobic segments accounts for 3-60% of the average degree of polymerization of the amphiphilic block copolymer.

[0037] In some embodiments, the active substance is selected from one or a combination of two or more of palmitoyl pentapeptide-4, palmitoyl tetrapeptide-7, blue ketone peptide, palmitoyl tripeptide-1, ganoderic triterpenes, ginsenosides, artemisinin, ferulic acid, astaxanthin, tea polyphenols, vitamin E, resveratrol, glycyrrhizin, rutin, quercetin, caffeine, penicillin G, omeprazole, imatinib, berberine, and quinine. The above-mentioned active substances have low solubility in water; for example, metformin has a solubility of 10-20 mg / ml in water at 20-25°C. Using the method of this invention to form a eutectic solution with an amphiphilic block copolymer can increase the solubility in water by 2-5 times. Astaxanthin is a typical hydrophobic active substance with a solubility of 0.1-1 μg / ml in water at 20-25℃. The solubility in water can be increased by more than 100 times after forming a eutectic solution with an amphiphilic block copolymer using the method of this invention.

[0038] In some embodiments, the polyol is selected from one or a combination of two or more of ethylene glycol, glycerol, butylene glycol, pentanediol, 1,2,5-pentanediol, dipentaerythritol, and pentaerythritol. Polyols have good hygroscopic properties and are commonly used humectants in personal care products. This invention uses an amphiphilic block copolymer and a polyol to form a eutectic solution, which can further prolong the moisturizing effect.

[0039] In some embodiments, the weight ratio of the amphiphilic block copolymer to the active substance is 10:0.0001-3. For example, the weight ratio of the amphiphilic block copolymer to the active substance can be any value or any value between 10:0.0001, 10:0.01, 10:0.1, 10:0.2, 10:0.3, 10:0.5, 10:0.6, 10:0.8, 10:1, 10:1.5, 10:2, 10:2.5, 10:3, etc., without particular limitation. Further, the weight ratio of the amphiphilic block copolymer to the active substance can be 10:0.1-2.

[0040] The weight ratio of the amphiphilic block copolymer to the polyol is 1:0.5-10. For example, the weight ratio of the amphiphilic block copolymer to the polyol can be any value or any value between 1:0.5, 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5, 1:5.5, 1:6, 1:6.5, 1:7, 1:7.5, 1:8, 1:8.5, 1:9, 1:9.5, 1:10, etc., without particular limitation. Further, the weight ratio of the amphiphilic block copolymer to the polyol can be 1:0.5-5.

[0041] On the other hand, the present invention also proposes a method for preparing the eutectic solution described in any of the above embodiments, wherein a raw material component comprising an amphiphilic block copolymer and an active substance and / or a polyol is mixed and stirred until a transparent state is obtained to obtain the eutectic solution. The eutectic solution of the present invention can be prepared by directly mixing a raw material component comprising an amphiphilic block copolymer and an active substance and / or the polyol at room temperature until a uniform and transparent state is achieved.

[0042] Furthermore, the present invention also proposes an application of the eutectic solution described in any of the above embodiments for the preparation of personal care products or pharmaceuticals. When using the eutectic solution of the present invention, it can be directly added to water and stirred to disperse evenly; the concentration in water can be 0.1-10 wt%.

[0043] The technical solutions of the present invention will be further described and explained below with reference to various embodiments.

[0044] Example 1 The block copolymer is PCL-PEG-PCL, the number average molecular weight of PEG is 600 g / mol, the viscosity of the block copolymer at 25℃ is 760 mPa·s, and the average degree of polymerization of PCL accounts for 48% of the average degree of polymerization of the block copolymer.

[0045] At room temperature, 10g of PCL-PEG-PCL block copolymer was added to a container, followed by 2g of resveratrol. The mixture was stirred at 100rpm until the solution became clear, yielding a eutectic solution. The appearance of the eutectic solution is shown in the attached figure. Figure 1 The right image shows a transparent, colorless solution, indicating that the block copolymer and resveratrol form a eutectic solution. (Comparison) Figure 1 In the left image, resveratrol is poorly soluble in water, so a 1 wt% aqueous dispersion appears turbid.

[0046] The eutectic solution in this embodiment remained transparent even after being left at room temperature for one month, indicating that the formed eutectic solution is very stable.

[0047] The above eutectic solution was added to deionized water to prepare a 2wt% aqueous solution. The aqueous solution was transparent to translucent, and the D value was measured by a laser particle size analyzer. 50 The particle size is 201 nm. TEM images of the aggregated particles in aqueous solution are attached. Figure 2 As shown, the aqueous solution remained transparent to translucent after being left at room temperature for one month without any change, indicating good stability.

[0048] The release test method for resveratrol in the above aqueous solution is as follows: A nylon membrane with a pore size of 0.2 μm is used to simulate a cell membrane. A tube with a pore size of 1 cm is divided into two parts. Ethanol / water (50:50, v / v) is added to the lower part as the acceptor part, and the above eutectic solution aqueous solution is injected into the upper part as the donor part. Then the tube is sealed. Every 1 h, 200 μL of the upper liquid is taken and the amount of resveratrol reduction is tested by HPLC. At the same time, 200 μL of block copolymer aqueous solution (concentration of 5 wt%) is added after each sampling.

[0049] The reduction in resveratrol in the eutectic solution aqueous solution is shown in Table 1 below.

[0050] Table 1

[0051] As can be seen from the data in Table 1 above, the eutectic solution of the present invention can achieve good release of the active substance resveratrol after dissolving in water.

[0052] Example 2 The block copolymer is PLLA-PEG-PLLA, the number average molecular weight of PEG is 400 g / mol, the viscosity of the block copolymer at 25℃ is 2780 mPa·s, and the average degree of polymerization of PLLA accounts for 45% of the average degree of polymerization of the block copolymer.

[0053] At room temperature, 10g of PLLA-PEG-PLLA block copolymer was added to a container, followed by the addition of 1g of astaxanthin. The mixture was stirred at 100rpm until the solution became transparent, yielding a eutectic solution. The eutectic solution remained transparent after being left at room temperature for one month.

[0054] The above eutectic solution was added to deionized water to prepare a 1 wt% aqueous solution. The aqueous solution was transparent to translucent, and the D value was measured by a laser particle size analyzer. 50 The particle size is 285 nm. The aqueous solution remained transparent to translucent for one month at room temperature without change, indicating good stability. Therefore, the block copolymer of this invention can form a eutectic solution with astaxanthin and achieves a solubilizing effect in water for astaxanthin that is insoluble in water (its solubility in water at 25°C is less than 1 mg / L).

[0055] Following the release test method in Example 1, the release of astaxanthin in the aqueous solution of the eutectic solution in this example is shown in Table 2 below.

[0056] Table 2

[0057] As can be seen from the data in Table 2 above, the eutectic solution of the present invention can achieve good release of the active substance astaxanthin after dissolving in water.

[0058] Example 3 The block copolymer is PLLA-PEG-PLLA, the number average molecular weight of PEG is 200 g / mol, the viscosity of the block copolymer at 25℃ is 3560 mPa·s, and the average degree of polymerization of PLLA accounts for 14% of the average degree of polymerization of the block copolymer.

[0059] At room temperature, 10g of PLLA-PEG-PLLA block copolymer was added to a container, followed by 1g of blue ketone peptide. The mixture was stirred at 60rpm until the solution became clear, yielding a eutectic solution. The eutectic solution remained clear after being left at room temperature for one month.

[0060] The above eutectic solution was added to deionized water to prepare a 3wt% aqueous solution. The aqueous solution was transparent to semi-transparent, and the D value was measured by a laser particle size analyzer. 50 The particle size is 237 nm. The aqueous solution remained transparent to translucent after being left at room temperature for one month without any change, indicating good stability.

[0061] Following the release test method in Example 1, the release of blue ketone peptides in the aqueous solution of the eutectic solution in this example is shown in Table 3 below.

[0062] Table 3

[0063] As can be seen from the data in Table 3 above, the eutectic solution of the present invention can achieve good release of the active substance - blue ketone peptide after dissolving in water.

[0064] Example 4 At room temperature, 10g of the PCL-PEG-PCL block copolymer from Example 1 was added to a container, followed by the addition of 10g of glycerol. The mixture was stirred at 100 rpm until the solution became clear, yielding a eutectic solution with the appearance shown in the attached figure. Figure 3 As shown, the eutectic solution remained transparent even after being left at room temperature for one month.

[0065] Add 20g of water to the eutectic solution and stir at 100 rpm until the solution becomes nearly transparent and homogeneous, obtaining an aqueous solution of the eutectic solution. The aqueous solution remained nearly transparent after being left at room temperature for one month, indicating good stability.

[0066] Moisturizing effect test method: Place approximately 10g of the sample to be tested into a 30×50mm flat weighing bottle, open it, and place it in an environment with 40% humidity and 20℃. Maintain constant ambient temperature and humidity, and weigh the sample at regular intervals. Calculate the weight difference of the sample before and after the test to determine the water loss rate of the sample. Water loss rate = (m0-m1) / m0×100%, where m0 is the initial weight of the sample and m1 is the weight of the sample at time t. The lower the water loss rate, the better the moisturizing effect.

[0067] A glycerol aqueous solution consisting of 20g glycerol and 20g water was used as a comparison. The moisturizing effects are shown in Table 4 below.

[0068] Table 4 Water loss rate / %

[0069] Therefore, as can be seen from the results in Table 4 above, the aqueous solution of the eutectic solution composed of the block copolymer of the present invention and glycerol has a lower water loss rate than the aqueous solution of glycerol, indicating that the eutectic solution has a better moisturizing effect than glycerol.

[0070] Example 5 At room temperature, 10g of the PLLA-PEG-PLLA block copolymer from Example 2 was added to a container, followed by the addition of 30g of glycerol. The mixture was stirred at 100rpm until the solution became transparent, yielding a eutectic solution. The eutectic solution remained transparent after being left at room temperature for one month.

[0071] Add 40g of water to the above eutectic solution and stir at 100 rpm until the solution becomes clear, obtaining an aqueous solution of the eutectic solution. The aqueous solution remains clear after being left at room temperature for one month, indicating good stability.

[0072] Following the water loss rate test method of Example 4, the water loss rate results of the aqueous solution of the eutectic solution in this example are shown in Table 5 below.

[0073] Table 5 Water Loss Rate / %

[0074] Comparing the data in Tables 5 and 4, the eutectic solution in this embodiment also exhibits better moisturizing properties than glycerol.

[0075] Example 6 The block copolymer is PCL-PEG-PCL, the number average molecular weight of PEG is 800 g / mol, the viscosity of the block copolymer at 25℃ is 830 mPa·s, and the average degree of polymerization of PCL accounts for 3% of the average degree of polymerization of the block copolymer.

[0076] Take 10g of the above PCL-PEG-PCL block copolymer and add it to a container. Then add 50g of glycerol and stir at 100rpm until the solution is clear to obtain a eutectic solution. The eutectic solution remains clear after being left at room temperature for 1 month.

[0077] Add 50g of water to the above eutectic solution and stir at 100rpm until the solution becomes nearly transparent and homogeneous, obtaining an aqueous solution of the eutectic solution. The aqueous solution remained nearly transparent after being left at room temperature for one month, indicating good stability.

[0078] Following the water loss rate test method of Example 4, the water loss rate results of the aqueous solution of the eutectic solution in this example are shown in Table 6 below.

[0079] Table 6 Water Loss Rate / %

[0080] Comparing the data in Tables 6 and 4, the eutectic solution in this embodiment also exhibits better moisturizing properties than glycerol.

[0081] As described above, the basic principles, main features, and advantages of the present invention have been shown and described. Those skilled in the art should understand that the present invention is not limited to the above embodiments, which are merely preferred embodiments and should not be construed as limiting the scope of the invention. All equivalent changes and modifications made in accordance with the scope of the patent and the description should still fall within the scope of the present invention. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A eutectic solution, characterized in that, It is composed of amphiphilic block copolymers and active substances; The weight ratio of the amphiphilic block copolymer to the active substance is 10:0.0001-3; The viscosity of the amphiphilic block copolymer at 25°C does not exceed 10000 mPa·s; The active substance contains at least two hydrogen bond donors; The amphiphilic block copolymer contains a number of oxygen atoms; The amphiphilic block copolymer is PCL-PEG-PCL, the viscosity of the amphiphilic block copolymer at 25°C is 760 mPa·s, the number average molecular weight of PEG is 600 g / mol, and the average degree of polymerization of PCL accounts for 48% of the average degree of polymerization of the amphiphilic block copolymer. Alternatively, the amphiphilic block copolymer is PLLA-PEG-PLLA, the viscosity of the amphiphilic block copolymer at 25°C is 2780 mPa·s, the number-average molecular weight of PEG is 400 g / mol, and the average degree of polymerization of PLLA accounts for 45% of the average degree of polymerization of the amphiphilic block copolymer; Alternatively, the amphiphilic block copolymer is PLLA-PEG-PLLA, the viscosity of the amphiphilic block copolymer at 25°C is 3560 mPa·s, the number-average molecular weight of PEG is 200 g / mol, and the average degree of polymerization of PLLA accounts for 14% of the average degree of polymerization of the amphiphilic block copolymer; The active substance is selected from one of the following: blue ketone peptide, palmitoyl tripeptide-1, ferulic acid, astaxanthin, resveratrol, and glycyrrhizin.

2. A method for preparing the eutectic solution according to claim 1, characterized in that, The raw material components containing the amphiphilic block copolymer and the active substance are mixed and stirred until transparent to obtain the eutectic solution.

3. An application of the eutectic solution according to claim 1, characterized in that, It is used in the preparation of personal care products.

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