Phase-change-controllable eutectic gel as well as preparation method and application thereof

Abstract

The invention relates to phase-change-controllable eutectic gel and a preparation method and application thereof.The eutectic gel comprises a eutectic solvent and a temperature-sensitive material, the eutectic solvent is formed by compounding a hydrogen bond acceptor and a hydrogen bond donor through hydrogen bond interaction, and the temperature-sensitive material is pluronic F127; the eutectic gel has a reversible sol-gel phase change behavior, the phase change temperature of the eutectic gel is regulated and controlled in a wide temperature range by adjusting the composition structure of the eutectic solvent, the ratio of a hydrogen bond acceptor to a hydrogen bond donor and the water content of Pluronic F127, and the phase change direction can be selected as forward temperature-sensitive change or reverse temperature-sensitive change. Compared with the prior art, by regulating and controlling the DES structure, the pluronic F127 water content and the proportion of the DES structure and the pluronic F127, forward and reverse reversible sol-gel phase change within the range of 0-60 DEG C can be achieved, and the phase change material is suitable for multiple scenes such as low-temperature storage, cold-chain transportation and intelligent cold compress.

Description

Technical Field

[0001] This invention relates to the field of polymer composite materials technology, and in particular to a eutectic gel with phase change control, its preparation method and application. Background Technology

[0002] Eutectic solvents (DES), as a green and designable solvent system, are formed by hydrogen bonded donors and acceptors. The network structure between its components disrupts the crystal arrangement, making DES liquid at room temperature. They possess advantages such as good biocompatibility and strong solubility, enabling efficient loading of poorly soluble drug components (such as metal oxides and biomacromolecules), demonstrating potential value in drug delivery. However, DES itself lacks gelling and controlled release capabilities, making it difficult to directly use as a highly efficient drug carrier. Existing technologies attempt to improve functionality through DES-based materials, but significant limitations remain. For example, the hemicellulose-based hydrogel described in publication number CN 114702697 A utilizes DES to enhance the solubility and conductivity of hemicellulose, focusing on applications in flexible wearable devices. However, its drug loading capacity is limited, and its phase transition temperature is fixed, making it impossible to achieve controllable drug release under varying temperature environments. The self-healing, high-adhesion, low-eutectic solvate gel developed in publication number CN 118909191 A improves its antifreeze and mechanical properties by introducing a polyhydroxyl enhancer, and is applied in the biomedical field. However, it does not solve the problem of adjustable phase transition temperature, resulting in unstable drug release behavior in temperature-sensitive scenarios such as cold chain transportation, making it difficult to meet the requirements for efficient delivery.

[0003] Comprehensive analysis reveals a common key technical problem with existing DES-based materials: a fixed phase transition temperature. This limits their application in efficient drug delivery and makes it difficult to meet the stringent requirements for temperature adjustability and controllable release in emerging scenarios such as cold chain transportation. Summary of the Invention

[0004] The purpose of this invention is to overcome the defects of the prior art by providing a phase transition-tunable eutectic gel, its preparation method, and its application. This invention uses a combination of hydrogen bond acceptor (HBA) and hydrogen bond donor (HBD) as a eutectic solvent (DES) and Pluronic F127 as a temperature-sensitive material. By controlling the structure of DES, the water content of Pluronic F127, and the ratio of the two, reversible sol-gel phase transitions in the forward and reverse directions within the range of 0~60℃ can be achieved.

[0005] In the conceptualization process of this invention, Pluronic F127 was considered to be a thermosensitive triblock copolymer surfactant. Its unique PEO-PPO-PEO structure allows it to dissolve in water at low temperatures and rapidly transform into a gel state near body temperature. Therefore, it is widely used as a drug carrier and gel matrix, exhibiting good biocompatibility and biodegradability. However, its fixed phase transition temperature limits its application in efficient drug delivery and makes it difficult to meet the needs of emerging scenarios such as cold chain transportation.

[0006] This deficiency primarily stems from the lack of dynamic tunability in the hydrogen bond network of DES, making the drug carrier unable to adapt to changes in external temperature, leading to uncontrolled release rates or functional failure. This invention addresses this core issue by innovatively designing the gelation mechanism and phase transition behavior of DES, aiming to overcome existing limitations and achieve temperature-responsive drug delivery.

[0007] The objective of this invention can be achieved through the following technical solutions: The first aspect of this invention provides a phase-change tunable eutectic gel, the eutectic gel comprising a eutectic solvent and a thermosensitive material, wherein the eutectic solvent is composed of a hydrogen bond acceptor and a hydrogen bond donor through hydrogen bonding, and the thermosensitive material is Pluronic F127. The eutectic gel exhibits reversible sol-gel phase transition behavior. The phase transition temperature of the eutectic gel can be controlled over a wide temperature range by adjusting the composition and structure of the eutectic solvent, the ratio of hydrogen bond acceptors to hydrogen bond donors, and the water content of Pluronic F127. Furthermore, the phase transition direction can be selected as either a positive or negative thermosensitive change.

[0008] Furthermore, the hydrogen bond acceptor is selected from at least one of quaternary ammonium salts (such as choline chloride, betaine, etc.) and their derivatives, amino acids (such as glycine, alanine, etc.) and their derivatives, amides (such as acetamide, etc.) and their derivatives, alkaloids (such as strychnine, etc.) and their derivatives; The hydrogen bond donor is selected from at least one of the following: alcohols (such as methanol, ethanol, propanol, etc.) and their derivatives; carboxylic acids (such as oxalic acid, malic acid, citric acid, lactic acid, etc.) and their derivatives; polyols (such as ethylene glycol, 1,3-propanediol, sorbitol, glycerol, etc.) and their derivatives; amides (such as urea, etc.) and their derivatives; phenols (such as phenol, catechol, etc.) and their derivatives; sugars (such as fructose, trehalose, sucrose, glucose, etc.) and their derivatives; and amino acids (such as proline, glutamic acid, etc.) and their derivatives. The hydrogen bond acceptor, based on its strong hydrogen bond acceptance ability, can form a stable hydrogen bond network with the hydrogen bond donor, thereby destroying their respective crystal structures and forming a uniform eutectic solvent. Preferably, the combination of betaine and lactic acid has a synergistic effect, which can improve the biocompatibility and phase transition sensitivity of the gel.

[0009] Furthermore, the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is (9~1):(1~9).

[0010] Furthermore, the eutectic gel can achieve reversible sol-gel phase transitions in both directions within the range of 0~60℃; The reversible sol-gel phase transition process includes: The hydrogen bond network in the eutectic solvent and the micelle structure of Pluronic F127 undergo dynamic reorganization through hydrogen bonding and hydrophobic balance. The positive temperature-sensitive change corresponds to the hydrogen bond network dominating and forming a sol state in the range of 0℃ to phase transition temperature T, and the Pluronic F127 micelles aggregating and forming a gel state in the range of phase transition temperature T to 60℃. The phase transition temperature T is adjusted within the range of 0~60℃ by the composition and ratio of the eutectic solvent.

[0011] The second aspect of this invention provides a method for preparing a phase-change-tunable eutectic gel as described above, comprising the following steps: S1. Mix the hydrogen bond acceptor and the hydrogen bond donor, and stir or rotary evaporate under heating conditions until a transparent and clear eutectic solvent is formed. Heating promotes the formation of hydrogen bonds. S2. Disperse Prönnick F127 in pure water at low temperature to obtain an aqueous solution of F127. S3. Under low temperature conditions, the eutectic solvent prepared in S1 is added to the F127 aqueous solution prepared in S2 and mixed evenly, so that the eutectic solvent and F127 can synergistically form a gel network through hydrogen bonding and hydrophobic interaction to obtain a eutectic gel.

[0012] Furthermore, in S1, the molar ratio of hydrogen bond acceptor to hydrogen bond donor is (9~1):(1~9); The heating conditions are as follows: continuous stirring within a temperature range of 50°C to 80°C until the hydrogen bond acceptor and hydrogen bond donor are completely fused through hydrogen bonding to form a uniform and transparent eutectic solvent.

[0013] Furthermore, in S2, the low-temperature condition is 0°C to 10°C; The concentration of F127 aqueous solution is 35~60wt%.

[0014] Furthermore, in S3, F127 ultimately accounts for 15-30% of the mass of the eutectic gel.

[0015] The third aspect of the present invention provides the application of the eutectic gel as described above, which is capable of phase change regulation, as a phase change energy storage material or thermal management medium in temperature regulation, as a thickener or gel matrix in a composition, as an active ingredient carrier or protectant in a composition, and as a smart material responsive to temperature changes in sensing and controlled release.

[0016] Furthermore, the applications of phase change energy storage materials or thermal management media can include cryogenic storage, cold chain transportation, intelligent cooling, and other applications, and can be extended to all scenarios that require temperature control, such as building energy conservation.

[0017] In low-temperature storage, the eutectic gel serves as a stabilizing matrix for heat-sensitive active ingredients. It utilizes its reverse thermosensitive phase transition properties to form a gel state at 2~8℃ and below, and fixes molecular motion through a hydrogen bond network to significantly delay activity decay. In this gel structure, heat-sensitive active ingredients (such as peptides, proteins, cytokines or easily oxidized small molecules) are embedded in a three-dimensional hydrogen bond network structure constructed between a eutectic solvent and Pluronic F127. Their Brownian motion is significantly restricted, which significantly reduces the rate of oxidation of active ingredients. Therefore, when using this eutectic gel as a stabilizing matrix, the long-term structural stability of active ingredients and the significant delay of activity decay can be achieved under conventional 2~8℃ cold storage or refrigerator conditions, thereby improving the product's shelf life.

[0018] In cold chain transportation, the eutectic gel serves as a temperature buffer medium, maintaining the gel state during transportation to protect the integrity of the goods. That is, it can remain in a continuous semi-solid gel state within the transportation temperature range of 0~10℃, and can be used as a temperature buffer layer inside the transportation container. During transportation, even if there are short-term fluctuations in the external temperature, the gel phase will not immediately transform into a fluid state due to its phase transition hysteresis, thus effectively maintaining the internal goods within the target temperature range. Simultaneously, the gel network provides physical encapsulation and mechanical shock protection for easily deformable goods, reducing the risk of damage during vibration and collisions. Therefore, this system can be used for temperature control and structural protection of products such as pharmaceuticals, food, and biomaterials that require cold chain transportation.

[0019] In the preparation of intelligent cold compress products, the eutectic gel serves as a carrier for thermotherapy. By adjusting the ratio of the eutectic solvent to Pluronic F127, forward / reverse phase transition switching is achieved in the range of 4~37℃, allowing the gel to continuously release cold or heat through the phase transition process after contacting the skin.

[0020] In other words, by increasing the content of the eutectic solvent, the system can be made to undergo a reverse phase transition, which is in a solution state at low temperature and rapidly transforms into a gel state upon contact with the skin. This allows the system to absorb heat during the phase transition, thereby generating a continuous cooling effect. Conversely, by increasing the content of F127, the system can be made to be in a gel state at room temperature and gradually swell at the temperature upon contact with the skin. This swelling process releases the stored heat, achieving the effect of thermotherapy. Therefore, compared to traditional cooling gels that require pre-freezing or pre-heating, this system can achieve adaptive cold / heat release by adjusting the formula ratio, which has better intelligence and convenience.

[0021] Furthermore, the uses of thickeners or gel matrixes can include applications in matrices for food, cosmetics, skin care products, and medical preparations, and can extend to industrial fields such as paints.

[0022] Furthermore, the uses of active ingredient carriers or protectants may include applications such as loading and delivery of drugs, cosmetic active ingredients, and food additives.

[0023] Furthermore, smart materials that respond to temperature changes can be used in applications such as drug controlled release, smart packaging, and sensors.

[0024] Compared with the prior art, the present invention has the following beneficial effects: The eutectic gel provided by this invention is a compound of eutectic solvent (DES) and Pluronic F127, enabling intelligent phase transition control of the gel. When F127 is used alone to formulate a hydrogel, it exhibits the characteristic of forming a sol at low temperatures and a gel at room temperature and above, thus limiting its application to human injection and implantation. With the addition of DES, the phase transition temperature of the eutectic gel can be adjusted by regulating its hydrogen bond network and micellar balance. Under certain conditions, it can even exhibit a reverse thermosensitive change, forming a gel at low temperatures and a sol at room temperature and above, thus enabling applications in various fields and scenarios. DES is a green raw material, and F127 is one of the longest-used and most widely used pharmaceutical-grade thermosensitive materials globally; the combination of the two enhances safety. Simultaneously, the excellent solubility of DES significantly broadens the drug delivery spectrum, allowing for the efficient encapsulation of poorly soluble small molecules, proteins, or cells. Release behavior can be intelligently controlled from immediate to sustained release, meeting personalized treatment needs. Attached Figure Description

[0025] Figure 1 The state diagrams of Example 1, Example 2, and the control sample at 0~60℃; Figure 2 The inverted state diagram of Example 2 at 4~37℃; Figure 3 The graph shows the DPPH radical scavenging capacity of different samples. Figure 4 The graph shows the scavenging capacity of ABTS radicals for different samples. Detailed Implementation

[0026] The embodiments of this application will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are only for illustrating this application and should not be regarded as limiting the scope of this application. Unless otherwise specified in the examples, conventional conditions are followed; unless the manufacturer of the reagents or instruments in the examples is specified, they are all commercially available products.

[0027] The eutectic gel of this invention uses a combination of hydrogen bond acceptor (HBA) and hydrogen bond donor (HBD) as a eutectic solvent (DES), and Pluronic F127 as a temperature-sensitive material. By controlling the DES structure, the water content of Pluronic F127, and the ratio of the two, reversible sol-gel phase transitions in both directions can be achieved within the range of 0-60°C. The eutectic gel provided by this invention possesses antioxidant and drug solubilizing properties, making it suitable for various scenarios such as low-temperature storage, cold chain transportation, and intelligent cold compresses.

[0028] The eutectic gel described in this invention uses a combination of hydrogen bond acceptor (HBA) and hydrogen bond donor (HBD) as a eutectic solvent (DES) and Pluronic F127 as a temperature-sensitive material.

[0029] In one embodiment of the present invention, the hydrogen bond acceptor (HBA) is at least one of quaternary ammonium salts (such as choline chloride, betaine, etc.) and their derivatives, amino acids (such as glycine, alanine, etc.) and their derivatives, amides (such as acetamide, etc.) and their derivatives, alkaloids (such as strychnine, etc.) and their derivatives; the hydrogen bond donor (HBD) is at least one of alcohols (such as methanol, ethanol, propanol, etc.) and their derivatives, carboxylic acids (such as oxalic acid, malic acid, citric acid, lactic acid, etc.) and their derivatives, polyols (such as ethylene glycol, 1,3-propanediol, sorbitol, glycerol, etc.) and their derivatives, amides (such as urea, etc.) and their derivatives, phenols (such as phenol, catechol, etc.) and their derivatives, sugars (such as fructose, trehalose, sucrose, glucose, etc.) and their derivatives, and amino acids (such as proline, glutamic acid, etc.) and their derivatives. Preferably, the hydrogen bond acceptor (HBA) is betaine and the hydrogen bond donor (HBD) is lactic acid.

[0030] In one embodiment of the present invention, the molar ratio of the hydrogen bond acceptor (HBA) to the hydrogen bond donor (HBD) is (9~1):(1~9).

[0031] Preferably, the molar ratio of the two is (3~1):(1~3).

[0032] In one embodiment of the present invention, the gel may encapsulate a drug, cells or active factors; Preferably, the drug is a poorly soluble polyphenol, protein, or vaccine.

[0033] In one embodiment of the present invention, the phase transition direction is: (S1) Positive temperature-sensitive changes: low-temperature sol, high-temperature gel; (S2) Reverse temperature-sensitive changes: low-temperature gel, high-temperature sol; The method for preparing the eutectic gel with intelligent phase transition control in this invention includes the following steps: (S1) Mix hydrogen bond acceptor (HBA) and hydrogen bond donor (HBD) in a certain proportion, and heat and stir or rotary evaporate until a clear liquid is formed to obtain eutectic solvent (DES). (S2) Disperse Prönnicke F127 in pure water at 4°C to obtain an aqueous solution of F127; (S3) Add DES to the F127 solution at 4°C and mix until homogeneous.

[0034] In practical applications, drugs, cells, or active factors can be added.

[0035] In one embodiment of the present invention, the concentration of the F127 aqueous solution is 35-60 wt%; Preferably, the concentration of the F127 aqueous solution is 40% w / w.

[0036] In one embodiment of the present invention, the F127 accounts for 15-30% of the total mass of the system; Preferably, the F127 accounts for 20% of the total mass.

[0037] The third objective of this invention is to provide an application of a low-eutectic gel with intelligent phase change control in low-temperature storage, cold chain transportation, and intelligent cold compress. The low-eutectic gel has antioxidant properties and adjustable positive and negative temperature-sensitive changes; it also has lubricating and moisturizing effects, and can play a role in multiple fields such as cosmetics and medicine.

[0038] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. Unless otherwise specified, all reagents used in the following embodiments are commercially available, and all detection methods and techniques used are conventional detection methods and techniques in the art.

[0039] Example 1 This embodiment provides a method for preparing a eutectic gel, specifically including the following steps: (S1) Weigh 10g of betaine raw material (such as anhydrous betaine) into a container, and slowly add 8g of lactic acid dropwise into the container. After the addition is complete, stir and dissolve the mixture at 50°C until a eutectic solvent (DES) is formed. (S2) Weigh 35g of Prönkel F127 into 100g of deionized water to form an aqueous solution of F127; (S3) Take 12g of the above DES and add 16g of the above F127 aqueous solution to mix, stir evenly, shake to defoam until a transparent and colorless sol is formed, and refrigerate for later use.

[0040] Example 2 This embodiment provides a method for preparing a eutectic gel, specifically including the following steps: (S1) Weigh 10g of betaine raw material (such as anhydrous betaine) into a container, and slowly add 16g of lactic acid dropwise into the container. After the addition is complete, stir and dissolve the mixture at 80°C until a eutectic solvent (DES) is formed. (S2) Weigh 60g of Prönkel F127 into 100g of deionized water to form an aqueous solution of F127; (S3) Take 12g of the above DES and add 6g of the above F127 aqueous solution to mix. Stir well, shake to defoam, until a transparent and colorless sol is formed, and refrigerate for later use.

[0041] Example 3 This embodiment provides a method for preparing a eutectic gel, specifically including the following steps: (S1) Weigh 14g of choline-based raw material (such as choline chloride) and 83g of glycerol into a container, add deionized water until both are completely dissolved, and then rotary evaporate the reaction until a eutectic solvent (DES) is formed. (S2) Weigh 10g of anthocyanin powder and dissolve it with the above DES in an ultrasonic machine at 60°C until the anthocyanin powder is evenly dispersed in the system; (S3) Weigh 40g of Prönkel F127 and dissolve it in 100g of deionized water to form an F127 aqueous solution; (S4) Take 12g of the above anthocyanin-DES system and add 24g of the above F127 aqueous solution to mix and stir evenly. Place in an ultrasonic machine to defoam and refrigerate for later use.

[0042] This embodiment utilizes the reverse thermosensitive phase transition property of eutectic gels, which exhibit a gel state at low temperatures. This provides a stable solid matrix environment for active ingredients such as anthocyanins, effectively reducing their degradation. It is suitable for the storage of substances such as vaccines, protein drugs, or cells that need to maintain their activity at low temperatures for a long time.

[0043] Example 4 This embodiment provides a method for preparing a eutectic gel, which differs from Example 3 in that: The raw materials for the prepared eutectic solvent were glycine and citric acid, with glycine weighing 35g and citric acid weighing 10g. Antioxidant experiments verified that its DPPH free radical scavenging and ABTS scavenging effects were close to those of the eutectic gel in Example 3.

[0044] Example 5 This embodiment provides a method for preparing a eutectic gel, which differs from Example 3 in that: The raw materials for the prepared eutectic solvent were acetamide and sorbitol, with 18g of acetamide and 18g of sorbitol. Antioxidant experiments verified that its DPPH free radical scavenging and ABTS scavenging effects were close to those of the eutectic gel in Example 3.

[0045] Example 6 This embodiment provides a method for preparing a eutectic gel, which differs from Example 3 in that: The raw materials for the prepared eutectic solvent were alanine and glucose, with alanine weighing 16g and glucose weighing 33g. Antioxidant experiments verified that its DPPH free radical scavenging and ABTS scavenging effects were close to those of the eutectic gel in Example 3.

[0046] Verification Example 1 (1) Determination of DPPH free radical scavenging rate: Weigh 2.3 mg of 1,1-diphenyl-2-trinitrophenylhydrazine (DPPH) into a test tube, add 40 ml of anhydrous ethanol to dissolve it. If necessary, sonication can be used to assist dissolution until the DPPH powder is completely dissolved, forming a deep purple DPPH solution. Use a UV spectrophotometer to measure its absorbance at 517 nm. The absorbance can be adjusted to between 1.2 and 1.3 using anhydrous ethanol and DPPH powder. Store in the dark at low temperature.

[0047] At room temperature, 4 mL of DPPH solution was placed in a test tube as a blank, and the absorbance was recorded as A0. 2 g of F127 (20% w / w), 2 g of DES (10 g betaine, 8 g lactic acid), and 2 g of DES (10 g betaine, 16 g lactic acid) were placed in test tubes, and 2 mL of DPPH solution was added to each tube as a control group. 2 g of the prepared eutectic gel was placed in a test tube, and 2 mL of DPPH solution was added to each tube as an experimental group. The absorbance values ​​of the control group and the experimental group were recorded as A. After thorough mixing, the mixture was reacted in the dark for 30 min. The mixture was then evenly distributed onto an ELISA plate, and the absorbance values ​​of the control and the sample were measured at 517 nm using an ELISA reader.

[0048] The formula for calculating DPPH free radical scavenging rate is: Where A0 is the absorbance of the blank control group and A is the absorbance of the experimental group.

[0049] (2) Determination of ABTS free radical scavenging rate: Weigh 19.2 mg of 2,2'-adiazon-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) into a test tube, dissolve in 5 mL of deionized water, and sonicate. Weigh 3.32 mg of potassium persulfate, dissolve in 5 mL of deionized water, and sonicate. After dissolving, mix the two solutions completely and store in a refrigerator protected from light for 12 hours.

[0050] Take 25 drops of the mixture in a test tube, add 0.1 mol / L PBS solution with a pH of 7.4, and measure its absorbance at 734 nm using a UV spectrophotometer. The absorbance can be adjusted to 0.7 ± 0.02 using the mixture and PBS. Store in the dark at low temperature.

[0051] At room temperature, 2 mL of ABTS solution was placed in a test tube as a blank, and the absorbance was recorded as A0. 1 g of F127 (20% w / w), 1 g of DES (10 g betaine, 8 g lactic acid), and 2 g of DES (10 g betaine, 16 g lactic acid) were placed in a test tube, and 2 mL of ABTS solution was added to each tube to create a control group. 1 g of the prepared eutectic gel was placed in a test tube, and 2 mL of ABTS solution was added to each tube to create an experimental group. The absorbance values ​​of the control group and the experimental group were recorded as A. After thorough mixing, the mixture was incubated in the dark for 6 minutes. The mixture was then evenly distributed onto an ELISA plate, and the absorbance of the control and sample was measured at 734 nm using an ELISA reader.

[0052] The formula for calculating the ABTS free radical scavenging rate is: Where A0 is the absorbance of the blank control group and A is the absorbance of the experimental group.

[0053] Results Analysis Figure 1 The diagrams show the state of the samples from Example 1, Example 2, and the control sample at temperatures ranging from 0 to 60°C. It can be seen that the sample from Example 1 is in a sol state at temperatures between 4 and 45°C and in a gel state at around 60°C; the sample from Example 2 is in a gel state at around 4°C and begins to transform into a sol state above 25°C; the control sample 20% w / w F127 is in a sol state at around 4°C and in a gel state above 25°C.

[0054] Figure 2 The diagram shows the inverted state of Example 2 at temperatures ranging from 4 to 37°C. It can be seen that the sample of Example 2 is in a gel state at 4°C, begins to undergo a phase transition at 25°C, and completely transforms into a sol state at 37°C.

[0055] DPPH free radical scavenging results are as follows Figure 3As shown, in the control group, the DPPH radical scavenging rate of F127 at a concentration of 20% w / w was 39.05%, the scavenging rate of DES with a betaine to lactate molar ratio of approximately 1:1 was 61.68%, and the scavenging rate of DES with a betaine to lactate molar ratio of approximately 1:2 was 63.47%. In the experimental group, the scavenging rate of Example 1 was 64.10%, and the scavenging rate of Example 2 was 67.89%. It can be clearly seen that the DPPH radical scavenging rate is improved after combining DES with F127. The above results indicate that the eutectic gel prepared in this example has a certain antioxidant effect, and its antioxidant properties are improved compared with F127 hydrogel of the same concentration and DES of the same formulation ratio.

[0056] ABTS free radical scavenging results are as follows Figure 4 As shown, in the control group, the ABTS radical scavenging rate of F127 at a concentration of 20% w / w was 49.26%, the scavenging rate of DES with a betaine to lactate molar ratio of approximately 1:1 was 49.23%, and the scavenging rate of DES with a betaine to lactate molar ratio of approximately 1:2 was 54.55%. In the experimental group, the scavenging rate of Example 1 was 42.49%, and the scavenging rate of Example 2 was 52.96%. It is also evident that the ABTS radical scavenging rate was significantly improved after combining DES with F127. These results indicate that the eutectic gel prepared in this example has a certain antioxidant effect, and its antioxidant properties are improved compared to F127 hydrogels of the same concentration and DES of the same formulation ratio.

[0057] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A eutectic gel with phase change tunable, characterized in that, The eutectic gel comprises a eutectic solvent and a thermosensitive material, wherein the eutectic solvent is composed of a hydrogen bond acceptor and a hydrogen bond donor through hydrogen bonding, and the thermosensitive material is Prönnick F127. The eutectic gel exhibits reversible sol-gel phase transition behavior. The phase transition temperature of the eutectic gel can be controlled over a wide temperature range by adjusting the composition and structure of the eutectic solvent, the ratio of hydrogen bond acceptors to hydrogen bond donors, and the water content of Pluronic F127. Furthermore, the phase transition direction can be selected as either a positive or negative thermosensitive change.

2. The eutectic gel with phase change control according to claim 1, characterized in that, The hydrogen bond acceptor is selected from at least one of quaternary ammonium salts and their derivatives, amino acids and their derivatives, amides and their derivatives, alkaloids and their derivatives, etc. The hydrogen bond donor is selected from at least one of alcohols and their derivatives, carboxylic acids and their derivatives, polyols and their derivatives, amides and their derivatives, phenols and their derivatives, sugars and their derivatives, amino acids and their derivatives, etc. The hydrogen bond acceptor, based on its strong hydrogen bond acceptance ability, can form a stable hydrogen bond network with the hydrogen bond donor, thereby destroying their respective crystal structures and forming a uniform eutectic solvent.

3. The eutectic gel with phase change control according to claim 1, characterized in that, The molar ratio of hydrogen bond acceptor to hydrogen bond donor is (9~1):(1~9).

4. The eutectic gel with phase change control according to claim 1, characterized in that, The eutectic gel can achieve reversible sol-gel phase transitions in both directions within the range of 0~60℃; The reversible sol-gel phase transition process includes: The hydrogen bond network in the eutectic solvent and the micelle structure of Pluronic F127 undergo dynamic reorganization through hydrogen bonding and hydrophobic balance. The positive temperature-sensitive change corresponds to the hydrogen bond network dominating and forming a sol state in the range of 0℃ to phase transition temperature T, and the Pluronic F127 micelles aggregating and forming a gel state in the range of phase transition temperature T to 60℃. The phase transition temperature T is adjusted within the range of 0~60℃ by the composition and ratio of the eutectic solvent.

5. A method for preparing a phase-transformable eutectic gel as described in any one of claims 1 to 4, characterized in that, Includes the following steps: S1. Mix the hydrogen bond acceptor and the hydrogen bond donor, and stir or rotary evaporate under heating conditions until a transparent and clear eutectic solvent is formed. Heating promotes the formation of hydrogen bonds. S2. Disperse Prönnick F127 in pure water at low temperature to obtain an aqueous solution of F127. S3. Under low temperature conditions, the eutectic solvent prepared in S1 is added to the F127 aqueous solution prepared in S2 and mixed evenly, so that the eutectic solvent and F127 can synergistically form a gel network through hydrogen bonding and hydrophobic interaction to obtain a eutectic gel.

6. The method for preparing a phase-change tunable eutectic gel according to claim 5, characterized in that, In S1, the molar ratio of hydrogen bond acceptor to hydrogen bond donor is (9~1):(1~9); The heating conditions are as follows: continuous stirring and purification within a temperature range of 50°C to 80°C until the hydrogen bond acceptor and hydrogen bond donor are completely fused through hydrogen bonding to form a homogeneous and transparent eutectic solvent.

7. The method for preparing a phase-change tunable eutectic gel according to claim 5, characterized in that, In S2, the low temperature condition is 0°C to 10°C; The concentration of F127 aqueous solution is 35~60wt%.

8. The method for preparing a phase-change tunable eutectic gel according to claim 5, characterized in that, In S3, F127 ultimately accounts for 15-30% of the mass of the eutectic gel.

9. The application of a phase change-tunable eutectic gel as described in any one of claims 1 to 4 as a phase change energy storage material or thermal management medium in temperature regulation, or as a thickener or gel matrix in a composition, or as an active ingredient carrier or protectant in a composition, or as a temperature-responsive smart material in sensing and controlled release.

10. The application of the phase-change tunable eutectic gel according to claim 9, characterized in that, The applications of the phase change energy storage material or thermal management medium in temperature regulation include: applications in low-temperature storage, cold chain transportation, and intelligent cold compress; The uses of the thickener or gel matrix include applications in the composition, including applications in food, cosmetics, skin care products, and medical formulations. The applications of active ingredient carriers or protectants in compositions include: applications in loading and delivering pharmaceuticals, cosmetic active ingredients, and food additives; The applications of smart materials that respond to temperature changes in sensing and controlled release include applications in drug controlled release, smart packaging, and sensors.

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