Gelatin-based high internal phase emulsion as well as preparation method and application thereof

Abstract

The invention relates to a gelatin-based high internal phase emulsion as well as a preparation method and application thereof. The gelatin-based high internal phase emulsion comprises a water phase and an oil phase; the water phase is prepared from the following raw materials: gelatin, water, glutaraldehyde and a disulfide bond cross-linking agent; the preparation raw materials of the oil phase comprise liquid paraffin and a compound emulsifier. The gelatin-based high-internal-phase emulsion foam material prepared from the gelatin-based high-internal-phase emulsion provided by the invention has the advantages of high porosity, high pore structure connectivity, good structural stability and support performance, good biocompatibility, realization of digestion, and small influence of the digestion process and product on cell activity.

Description

Technical Field

[0001] This invention relates to the field of high internal phase emulsion technology, and in particular to a gelatin-based high internal phase emulsion, its preparation method, and its application. Background Technology

[0002] High internal phase emulsion (HIPE), also known as ultra-concentrated emulsion or gel emulsion, is a type of emulsion with a dispersed phase volume fraction of 74% or higher. Porous functional materials prepared from HIPE possess advantages such as high specific surface area, high porosity, and light weight, and can be applied in various fields such as cell culture and daily chemical hygiene products. In the daily chemical hygiene product field, for example, sanitary napkins and dressings offer advantages such as absorption, flow conduction, water retention, anti-backflow, or sustained release.

[0003] Traditional two-dimensional cell culture cannot simulate the three-dimensional microenvironment of cells in vivo. 3D cell culture, which can simulate the in vivo microenvironment, has become a core technology in cell biology and regenerative medicine. Porous 3D cell scaffold materials are the key carriers for 3D culture.

[0004] Currently, porous 3D cell scaffold materials suffer from problems such as poor controllability of degradation, which can easily affect cell viability, or poor controllability of porosity, making it difficult to form highly interconnected macroporous structures. Although synthetic polymer scaffolds (such as PLGA and PCL) have good biocompatibility and controllable porosity, their degradation products (such as lactic acid) can easily lead to local acidic environments, affecting cell viability. Natural materials (such as collagen sponges and alginate gels) have good biocompatibility, but traditional preparation methods such as freeze-drying or lyophilized foaming are insufficient to form highly interconnected macropores (pore size <50μm) for porous 3D cell scaffold materials, limiting cell colonization and nutrient delivery.

[0005] The current digestion methods for porous 3D cell scaffold materials can easily affect cell viability. The digestion of porous 3D cell scaffold materials usually requires strong acid / base (such as PLGA which needs to be soaked in NaOH for 4~8 hours) or high temperature (>50℃), which can easily lead to cell denaturation and cell viability.

[0006] Therefore, there is a need to develop a high internal phase emulsion that can prepare porous 3D cell scaffold materials with highly interconnected macroporous structures, structural stability, good support, good biocompatibility, the ability to be digested, and minimal impact on cell viability. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a gelatin-based high internal phase emulsion, its preparation method, and its application. The gelatin-based high internal phase emulsion foam material prepared from the gelatin-based high internal phase emulsion has the advantages of high porosity, high pore structure connectivity, good structural stability and support, good biocompatibility, the ability to digest, and minimal impact of the digestion process and products on cell activity.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides a gelatin-based high internal phase emulsion, the gelatin-based high internal phase emulsion comprising an aqueous phase and an oil phase; the raw materials for preparing the aqueous phase include gelatin, water, glutaraldehyde and a disulfide crosslinking agent; the raw materials for preparing the oil phase include liquid paraffin and a composite emulsifier.

[0010] Due to its water solubility and temperature-sensitive gel properties, gelatin is difficult to prepare into high internal phase emulsion foam materials using conventional emulsion template methods. During the emulsification process, gelatin tends to gel prematurely (gelation temperature 20~30℃), causing the oil phase droplets to coalesce, resulting in low porosity (porosity <80%) and an inability to form a stable high porosity structure. This invention prepares a gelatin-based high internal phase emulsion by using an aqueous phase made of gelatin, water, glutaraldehyde, and a disulfide crosslinking agent, and an oil phase made of liquid paraffin and a composite emulsifier. A glutaraldehyde-disulfide crosslinking agent composite crosslinking system is formed. Glutaraldehyde helps construct the basic crosslinking network of gelatin, ensuring the structural stability of the gelatin-based high internal phase emulsion foam material made from the emulsion during cell culture. The disulfide crosslinking agent introduces disulfide bond crosslinking points that respond to breakage, providing sites for rapid dissolution under specific stimuli. The resulting gelatin-based high internal phase emulsion foam material possesses both stable support and dissolution characteristics. The composite emulsifier reduces the interfacial tension between the aqueous and oil phases, decreasing oil phase droplet aggregation. The resulting gelatin-based high internal phase emulsion foam material exhibits high porosity and high connectivity.

[0011] Preferably, the raw materials for preparing the aqueous phase include the following components by weight: 10 parts gelatin, 35-85 parts water (e.g., 40, 45, 50, 55, 60, 65, 70, 75 or 80 parts, etc.), 0.05-0.3 parts glutaraldehyde (e.g., 0.08, 0.11, 0.14, 0.17, 0.20, 0.23, 0.26 or 0.29 parts, etc.), and 0.5-5 parts disulfide crosslinking agent (e.g., 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts or 4.5 parts, etc.).

[0012] Preferably, based on the total mass of the raw materials for the preparation of the aqueous phase as 100%, the mass of glutaraldehyde is 0.1% to 0.3%, for example, 0.12%, 0.14%, 0.16%, 0.18%, 0.2%, 0.22%, 0.24%, 0.26%, or 0.28%.

[0013] Preferably, the water comprises deionized water.

[0014] Preferably, the disulfide crosslinking agent comprises cystamine dihydrochloride.

[0015] Preferably, the aqueous phase further includes a pH adjuster.

[0016] Preferably, the pH adjuster comprises an acid and / or a base.

[0017] Preferably, the pH of the aqueous phase is 6 to 8, such as 6.2, 6.4, 6.8, 7.0, 7.2, 7.4, 7.6 or 7.8.

[0018] Preferably, the composite emulsifier includes a hydrophilic surfactant and a hydrophobic surfactant.

[0019] Preferably, the hydrophilic surfactant has an HLB value of 10 to 18, such as 11, 12, 13, 14, 15, 16 or 17.

[0020] Preferably, the hydrophilic surfactant includes Tween 80 (HLB value 15.0).

[0021] Preferably, the hydrophobic surfactant has an HLB value of 3 to 6, such as 3.5, 4, 4.5, 5 or 5.5.

[0022] Preferably, the hydrophobic surfactant includes Span 80 (HLB value 4.3).

[0023] Preferably, the mass ratio of the hydrophilic surfactant to the hydrophobic surfactant is (0.1~10):1, for example, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1 or 9:1, etc.

[0024] Preferably, the raw materials for preparing the oil phase include the following components by weight: 20 parts liquid paraffin and 1-10 parts composite emulsifier.

[0025] Preferably, the mass ratio of the aqueous phase to the oil phase is (4~10):1, for example, 5:1, 6:1, 7:1, 8:1 or 9:1.

[0026] In a second aspect, the present invention provides a method for preparing a gelatin-based high internal phase emulsion as described in the first aspect, the method comprising the following steps: mixing an aqueous phase and an oil phase to obtain the gelatin-based high internal phase emulsion.

[0027] Preferably, the aqueous phase is prepared by the following method: dissolving gelatin in water, then adding a disulfide crosslinking agent and stirring to mix, adding glutaraldehyde dropwise to react, and adding a pH adjuster to adjust the pH to 6-8 (e.g., 6.2, 6.4, 6.8, 7.0, 7.2, 7.4, 7.6 or 7.8, etc.) to obtain the aqueous phase.

[0028] Preferably, the melting temperature is 60~80℃, such as 62℃, 64℃, 66℃, 68℃, 70℃, 72℃, 74℃, 76℃ or 78℃.

[0029] Preferably, the reaction temperature is 60~80℃, such as 62℃, 64℃, 66℃, 68℃, 70℃, 72℃, 74℃, 76℃ or 78℃.

[0030] Preferably, the reaction time is 20 to 30 minutes, such as 21 minutes, 22 minutes, 23 minutes, 24 minutes, 25 minutes, 26 minutes, 27 minutes, 28 minutes, or 29 minutes.

[0031] Preferably, the oil phase is prepared by mixing liquid paraffin and a composite emulsifier to obtain the oil phase.

[0032] Preferably, the mixing of the aqueous phase and the oil phase includes adding the aqueous phase dropwise to the oil phase under a first stirring, followed by a second stirring and mixing.

[0033] Preferably, the rotation speed of the first stirring and the second stirring is independently 1000~2000 rpm, such as 1100 rpm, 1200 rpm, 1300 rpm, 1400 rpm, 1500 rpm, 1600 rpm, 1700 rpm, 1800 rpm or 1900 rpm.

[0034] Preferably, the dripping rate is 1 to 5 mL / min, such as 1.5 mL / min, 2 mL / min, 2.5 mL / min, 3 mL / min, 3.5 mL / min, 4 mL / min or 4.5 mL / min.

[0035] Preferably, the second stirring time is 10 to 30 minutes, such as 12 minutes, 14 minutes, 16 minutes, 18 minutes, 20 minutes, 22 minutes, 24 minutes, 26 minutes or 28 minutes.

[0036] In this invention, the composite crosslinking system of glutaraldehyde and disulfide crosslinking agent forms a synergistic effect with the composite emulsifier: glutaraldehyde and disulfide crosslinking agent react simultaneously at 60~80℃, which not only avoids premature gelation of gelatin at low temperature, but also increases the viscosity of the aqueous phase through crosslinking, thereby enhancing the encapsulation stability of oil phase droplets; the HLB value of the composite emulsifier (hydrophilic surfactant and hydrophobic surfactant) is synergistically matched with the gelatin-containing aqueous phase (HLB value of about 9~11), so that the oil phase droplets are uniformly dispersed, and the emulsion stability period after emulsification is ≥24h, providing sufficient time for subsequent curing.

[0037] Thirdly, the present invention provides a gelatin-based high internal phase emulsion foam material, wherein the gelatin-based high internal phase emulsion foam material is prepared by curing and drying the gelatin-based high internal phase emulsion as described in the first aspect.

[0038] In this invention, the gelatin-based high internal phase emulsion foam material can be controlled and digested in two ways: 1. Enzymatic hydrolysis: The gelatin component in the gelatin-based high internal phase emulsion foam material can be specifically hydrolyzed by trypsin, and the disulfide bond cross-linking points do not affect the enzymatic hydrolysis efficiency; 2. Reduction pathway: If it is necessary to avoid the potential impact of enzymes on cells, the disulfide bond cross-linking points can be broken by reduction, for example, by using the reducing agent dithiothreitol (DTT). At the same time, the gelatin slowly swells in a neutral environment, achieving complete digestion of the gelatin-based high internal phase emulsion foam material. Both pathways can gently release cells.

[0039] Preferably, the curing includes cold curing.

[0040] Preferably, the temperature for cold curing is 0~15℃, such as 2℃, 4℃, 6℃, 8℃, 10℃, 12℃ or 14℃.

[0041] Preferably, the refrigeration curing time is 10~24 h, such as 12 h, 14 h, 16 h, 18 h, 20 h or 22 h.

[0042] Preferably, the curing process further includes an extraction and degreasing step.

[0043] In this invention, the extraction for oil removal refers to the removal of liquid paraffin. Exemplarily, the extraction includes using 95% ethanol (composed of 95% ethanol and 5% water by volume) as the extractant, immersing and extracting at room temperature (25°C), with each immersion extraction lasting 2 hours and repeated 3 times to ensure complete removal of the oil phase and avoid residues affecting cell activity.

[0044] Preferably, the oil removal process includes oil removal using ethanol.

[0045] Preferably, the drying includes vacuum drying.

[0046] Preferably, the vacuum drying temperature is 20~30℃, such as 21℃, 22℃, 23℃, 24℃, 25℃, 26℃, 27℃, 28℃ or 29℃.

[0047] Preferably, the vacuum drying time is 5 to 20 hours, such as 7 hours, 9 hours, 11 hours, 13 hours, 15 hours, 17 hours, or 19 hours.

[0048] Fourthly, the present invention provides the application of a gelatin-based high internal phase emulsion foam material as described in the first aspect in 3D cell culture or daily chemical hygiene products.

[0049] For example, the gelatin-based high internal phase emulsion foam material can be used in the field of 3D cell culture to provide cells with a 3D environment that is closer to the natural tissue environment.

[0050] For example, the gelatin-based high internal phase emulsion foam material can be used in the field of sanitary napkins, dressings, and other daily chemical hygiene products. One or more layers of gelatin-based high internal phase emulsion foam material with the same or different pore sizes can be used as the core of sanitary napkins, dressings, and other daily chemical hygiene products. Through its high porosity, high connectivity, and controllable pore size, it can absorb, guide, lock in water, prevent backflow, or slowly release liquids such as water, menstrual blood, blood, body fluids, and nutrients, giving the product excellent properties such as thinness, dryness, long-lasting effect, and slow release.

[0051] Compared with the prior art, the present invention has at least the following beneficial effects:

[0052] In this invention, a gelatin-based high internal phase emulsion is prepared using an aqueous phase made of gelatin, water, glutaraldehyde, and a disulfide crosslinking agent, and an oil phase made of liquid paraffin and a composite emulsifier. The gelatin-based high internal phase emulsion foam material prepared using this emulsion exhibits advantages such as high porosity and high connectivity, good structural stability and support, good biocompatibility, the ability to digest, and minimal impact of the digestion process and products on cell activity. The porosity of the prepared gelatin-based high internal phase emulsion foam material is ≥75%, and the connectivity is ≥88%. Preferably, the porosity of the gelatin-based high internal phase emulsion foam material is ≥80%, and the connectivity is ≥90%. Attached Figure Description

[0053] Figure 1 The image shows a SEM image of the gelatin-based high internal phase emulsion foam material provided in Example 1. Detailed Implementation

[0054] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0055] Unless otherwise specified, the materials and equipment involved in the following detailed embodiments are all conventional materials and equipment in the art and will not affect the technical effects of the present invention.

[0056] The sources of some of the raw materials used in the following examples and comparative examples are as follows:

[0057] Gelatin: Model number G9382, manufacturer: Sigma-Aldrich;

[0058] Liquid paraffin: AR grade, manufactured by Sinopharm Chemical Reagent Co., Ltd.

[0059] Example 1

[0060] This embodiment provides a gelatin-based high internal phase emulsion, its preparation method, and a gelatin-based high internal phase emulsion foam material. The gelatin-based high internal phase emulsion is prepared by the following method:

[0061] (1) Dissolve 10 parts by weight of gelatin (model G9382) in 65 parts by weight of deionized water at 60°C, then add 1.5 parts by weight of disulfide crosslinking agent (cystamine dihydrochloride) and stir to mix, add 0.2 parts by weight of glutaraldehyde dropwise and react at 65°C for 20 minutes, then add pH adjuster (1 mol / L hydrochloric acid) to adjust the pH to 6.8 to obtain the aqueous phase.

[0062] (2) Mix 20 parts by weight of liquid paraffin (AR grade), 2 parts by weight of hydrophilic surfactant (Tween 80) and 1 part by weight of lipophilic surfactant (Span 80) to obtain the oil phase.

[0063] (3) Under the first stirring at 1500 rpm, the aqueous phase obtained in step (1) is added dropwise to the oil phase obtained in step (2) at a rate of 3 mL / min. The mass ratio of the aqueous phase to the oil phase is 7:1. Then, the second stirring is carried out at 1500 rpm for 20 min to obtain the gelatin-based high internal phase emulsion.

[0064] The gelatin-based high internal phase emulsion foam material was prepared by the following method:

[0065] The gelatin-based high internal phase emulsion was refrigerated and cured at 4°C for 12 h. 95% ethanol (composed of 95% ethanol and 5% water by volume) was used as the extractant, and the emulsion was extracted by soaking at room temperature (25°C) for 2 h each time, repeated 3 times. The emulsion was then vacuum dried at 30°C for 8 h to obtain the gelatin-based high internal phase emulsion foam material.

[0066] Example 2

[0067] This embodiment provides a gelatin-based high internal phase emulsion, its preparation method, and a gelatin-based high internal phase emulsion foam material. The gelatin-based high internal phase emulsion is prepared by the following method:

[0068] (1) Dissolve 10 parts by weight of gelatin (model G9382) in 35 parts by weight of deionized water at 60°C, then add 0.5 parts by weight of disulfide crosslinking agent (cystamine dihydrochloride) and stir to mix, add 0.1 parts by weight of glutaraldehyde dropwise and react at 62°C for 20 minutes, then add pH adjuster (1 mol / L sodium hydroxide) to adjust the pH to 7 to obtain the aqueous phase.

[0069] (2) Mix 20 parts by weight of liquid paraffin (AR grade), 1 part by weight of hydrophilic surfactant (Tween 80) and 7 parts by weight of lipophilic surfactant (Span 80) to obtain the oil phase.

[0070] (3) Under the first stirring at 1000 rpm, the aqueous phase obtained in step (1) is added dropwise to the oil phase obtained in step (2) at a rate of 5 mL / min. The mass ratio of the aqueous phase to the oil phase is 4:1. Then, the second stirring is carried out at 1000 rpm for 20 min to obtain the gelatin-based high internal phase emulsion.

[0071] The gelatin-based high internal phase emulsion foam material was prepared by the following method:

[0072] The gelatin-based high internal phase emulsion was refrigerated and cured at 3°C ​​for 10 h. 95% ethanol (composed of 95% ethanol and 5% water by volume) was used as the extractant, and the emulsion was extracted by soaking at room temperature (25°C) for 2 h each time, repeated 3 times. The emulsion was then vacuum dried at 25°C for 12 h to obtain the gelatin-based high internal phase emulsion foam material.

[0073] Example 3

[0074] This embodiment provides a gelatin-based high internal phase emulsion, its preparation method, and a gelatin-based high internal phase emulsion foam material. The gelatin-based high internal phase emulsion is prepared by the following method:

[0075] (1) Dissolve 10 parts by weight of gelatin (model G9382) in 85 parts by weight of deionized water at 60°C, then add 5 parts by weight of disulfide crosslinking agent (cystamine dihydrochloride) and stir to mix, add 0.3 parts by weight of glutaraldehyde and react at 70°C for 20 minutes, then add pH adjuster (1 mol / L hydrochloric acid) to adjust the pH to 6.5 to obtain the aqueous phase.

[0076] (2) Mix 20 parts by weight of liquid paraffin (AR grade), 8 parts by weight of hydrophilic surfactant (Tween 80) and 1 part by weight of lipophilic surfactant (Span 80) to obtain the oil phase.

[0077] (3) Under the first stirring at 2000 rpm, the aqueous phase obtained in step (1) is added dropwise to the oil phase obtained in step (2) at a rate of 1 mL / min. The mass ratio of the aqueous phase to the oil phase is 10:1. Then, the second stirring is carried out at 2000 rpm for 20 min to obtain the gelatin-based high internal phase emulsion.

[0078] The gelatin-based high internal phase emulsion was refrigerated and cured at 10°C for 24 h. 95% ethanol (composed of 95% ethanol and 5% water by volume) was used as the extractant, and the emulsion was extracted by soaking at room temperature (25°C) for 2 h each time, repeated 3 times. The emulsion was then vacuum dried at 30°C for 8 h to obtain the gelatin-based high internal phase emulsion foam material.

[0079] Example 4

[0080] This embodiment provides a gelatin-based high internal phase emulsion, its preparation method, and a gelatin-based high internal phase emulsion foam material. The difference between this embodiment and Example 1 is that the weight of the disulfide crosslinking agent (cystamine dihydrochloride) in step (1) is adjusted to 6 parts, while other conditions are the same as in Example 1.

[0081] Example 5

[0082] This embodiment provides a gelatin-based high internal phase emulsion, its preparation method, and a gelatin-based high internal phase emulsion foam material. The difference between this embodiment and Example 1 is that the weight of the disulfide crosslinking agent (cystamine dihydrochloride) in step (1) is adjusted to 0.3 parts, while other conditions are the same as in Example 1.

[0083] Example 6

[0084] This embodiment provides a gelatin-based high internal phase emulsion, its preparation method, and a gelatin-based high internal phase emulsion foam material. The difference between this embodiment and Example 1 is that the weight of glutaraldehyde in step (1) is adjusted to 0.35 parts, while other conditions are the same as in Example 1.

[0085] Example 7

[0086] This embodiment provides a gelatin-based high internal phase emulsion, its preparation method, and a gelatin-based high internal phase emulsion foam material. The difference between this embodiment and Example 1 is that the weight of glutaraldehyde in step (1) is adjusted to 0.04 parts, while other conditions are the same as in Example 1.

[0087] Example 8

[0088] This embodiment provides a gelatin-based high internal phase emulsion, its preparation method, and a gelatin-based high internal phase emulsion foam material. The difference between this embodiment and Embodiment 1 is that the second stirring speed in step (3) is adjusted to 2200 rpm, while other conditions are the same as in Embodiment 1.

[0089] Comparative Example 1

[0090] This comparative example provides a gelatin-based high internal phase emulsion, its preparation method, and a gelatin-based high internal phase emulsion foam material. The difference between this example and Example 1 is that glutaraldehyde is not added in step (1), and the other conditions are the same as in Example 1.

[0091] Comparative Example 2

[0092] This comparative example provides a gelatin-based high internal phase emulsion, its preparation method, and a gelatin-based high internal phase emulsion foam material. The difference between this example and Example 1 is that no disulfide crosslinking agent is added in step (1), while other conditions are the same as in Example 1.

[0093] Comparative Example 3

[0094] This comparative example provides a gelatin-based high internal phase emulsion and its preparation method, as well as a gelatin-based high internal phase emulsion foam material. The difference between this example and Example 1 is that in step (2), no lipophilic surfactant is added, and the weight of the hydrophilic surfactant (Tween 80) is adjusted to 3 parts. Other conditions are the same as in Example 1.

[0095] Comparative Example 4

[0096] This comparative example provides a gelatin-based high internal phase emulsion and its preparation method, as well as a gelatin-based high internal phase emulsion foam material. The difference between this example and Example 1 is that in step (1), no hydrophilic surfactant is added, and the weight of the lipophilic surfactant (Span 80) is adjusted to 3 parts. Other conditions are the same as in Example 1.

[0097] The gelatin-based high internal phase emulsion foam materials provided in Examples 1-8 and Comparative Examples 1-4 were subjected to the following performance tests.

[0098] (1) Porosity test: The liquid displacement method (anhydrous ethanol) was used for testing. The gelatin-based high internal phase emulsion foam material was vacuum dried at 50℃ for 12 h and weighed (recorded as m1). Then it was immersed in anhydrous ethanol and degassed under vacuum for 30 min to ensure that it was fully saturated with anhydrous ethanol. The weight was then recorded as m2. The volume V was measured by the water displacement method. The porosity was calculated as (m2-m1) / (ρ×V)×100%, where ρ is the density of anhydrous ethanol, ρ=0.789g / cm³. 3 .

[0099] (2) Average pore diameter: The diameter of 100 pores was randomly measured and averaged using a scanning electron microscope (SEM, TESCAN MIRA3).

[0100] (3) Connectivity: Observation was performed using a scanning electron microscope (SEM, TESCAN MIRA3). The number of connected channels was counted from 100 randomly observed channels. Connectivity = Number of connected channels / Total number of channels × 100%.

[0101] (4) Digestion performance test: Digestion was performed at 37°C using trypsin solution (0.25% mass percentage of trypsin, commercially available) and at 25°C using DTT-PBS solution (10 mmol / L concentration, pH=7.4, commercially available), and the complete digestion time was recorded. The effect of the digestion solution on the activity of L929 cells was tested using the CCK-8 method (24h of culture, cell viability retention rate ≥90% is qualified).

[0102] (5) Structural stability: The compressive modulus was tested using a universal testing machine (Instron 5967). The sample size was 5mm×5mm×5mm, the compression rate was 1mm / min, and the compressive stress at 8% strain was taken. The compressive modulus was calculated. If the compressive modulus was ≥0.1MPa, it was recorded as "no collapse". If the compressive modulus was ≥0.05MPa and <0.1MPa, it was recorded as "partial collapse". If the compressive modulus was <0.05MPa, it was recorded as "complete collapse".

[0103] The test results are shown in Table 1 below.

[0104] Table 1

[0105]

[0106] According to the test results in Table 1, the gelatin-based high internal phase emulsion foam materials provided in Examples 1-8 have a porosity of ≥75% and a connectivity of ≥88%, enabling digestion and minimizing the impact of digestion products on cell activity.

[0107] Figure 1 The image shows a SEM image of the gelatin-based high internal phase emulsion foam material provided in Example 1, with interconnected channels.

[0108] Compared with Example 1, if the weight fraction of the disulfide crosslinking agent is too high (Example 4), excessive crosslinking leads to a decrease in porosity and connectivity, resulting in a dense structure; if the weight fraction of the disulfide crosslinking agent is too low (Example 5), insufficient crosslinking leads to a decrease in structural stability and local collapse. Therefore, it can be seen that the gelatin-based high internal phase emulsion foam material prepared by controlling the weight fraction of the disulfide crosslinking agent in the aqueous phase within a specific range has better performance.

[0109] Compared with Example 1, if the weight fraction of glutaraldehyde is too high (Example 6), excessive basic cross-linking leads to a decrease in porosity and connectivity, and a slower digestion rate; if the weight fraction of glutaraldehyde is too low (Example 7), weak basic cross-linking leads to poor structural stability and local collapse. Therefore, it can be seen that the gelatin-based high internal phase emulsion foam material prepared by controlling the weight fraction of glutaraldehyde in the aqueous phase within a specific range has better performance.

[0110] Compared with Example 1, if the second stirring speed is too low (Example 8), the stability of the gelatin-based high internal phase emulsion is impaired, local droplet breakage leads to a decrease in structural stability and local collapse. Therefore, it can be seen that the gelatin-based high internal phase emulsion foam material prepared by controlling the second stirring speed within a specific range has better performance.

[0111] Compared with Example 1, if glutaraldehyde (Comparative Example 1) is not added, there is no basic cross-linking network, resulting in poor structural stability, complete collapse, and inability to achieve the supporting function.

[0112] Compared to Example 1, without the addition of a disulfide crosslinking agent (Comparative Example 2), there are no responsive digestion sites, and the gelatin-based high internal phase emulsion foam material cannot be completely digested.

[0113] Compared with Example 1, if no lipophilic surfactant is added (Comparative Example 3) or no hydrophilic surfactant is added (Comparative Example 4), there is no composite emulsification effect, the oil phase is unevenly dispersed, and the porosity and connectivity decrease.

[0114] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A gelatin-based high internal phase emulsion, characterized in that, The gelatin-based high internal phase emulsion comprises an aqueous phase and an oil phase; The raw materials for preparing the aqueous phase include gelatin, water, glutaraldehyde, and disulfide crosslinking agent; The raw materials for preparing the oil phase include liquid paraffin and a composite emulsifier.

2. The gelatin-based high internal phase emulsion according to claim 1, characterized in that, The raw materials for preparing the aqueous phase include the following components by weight: 10 parts gelatin, 35-85 parts water, 0.05-0.3 parts glutaraldehyde, and 0.5-5 parts disulfide crosslinking agent.

3. The gelatin-based high internal phase emulsion according to claim 1 or 2, characterized in that, The water includes deionized water; Preferably, the disulfide crosslinking agent comprises cystamine dihydrochloride; Preferably, the aqueous phase further includes a pH adjuster; Preferably, the pH adjuster comprises an acid and / or a base; Preferably, the pH of the aqueous phase is 6 to 8.

4. The gelatin-based high internal phase emulsion according to any one of claims 1 to 3, characterized in that, The composite emulsifier includes hydrophilic surfactants and hydrophobic surfactants; Preferably, the hydrophilic surfactant has an HLB value of 10 to 18; Preferably, the hydrophilic surfactant includes Tween 80; Preferably, the hydrophobic surfactant has an HLB value of 3 to 6; Preferably, the hydrophobic surfactant includes Span 80; Preferably, the mass ratio of the hydrophilic surfactant to the hydrophobic surfactant is (0.1~10):1; Preferably, the raw materials for preparing the oil phase include the following components by weight: 20 parts liquid paraffin and 1-10 parts composite emulsifier; Preferably, the mass ratio of the aqueous phase to the oil phase is (4~10):

1.

5. A method for preparing a gelatin-based high internal phase emulsion as described in any one of claims 1 to 4, characterized in that, The preparation method includes the following steps: mixing the aqueous phase and the oil phase to obtain the gelatin-based high internal phase emulsion.

6. The preparation method according to claim 5, characterized in that, The aqueous phase was prepared by the following method: gelatin was dissolved in water, then a disulfide crosslinking agent was added and stirred, glutaraldehyde was added dropwise to react, and a pH adjuster was added to adjust the pH to 6-8 to obtain the aqueous phase. Preferably, the melting temperature is 60~80℃; Preferably, the reaction temperature is 60~80℃; Preferably, the reaction time is 20-30 min; Preferably, the oil phase is prepared by mixing liquid paraffin and a composite emulsifier to obtain the oil phase.

7. The preparation method according to claim 5 or 6, characterized in that, The mixing of the aqueous phase and the oil phase includes adding the aqueous phase dropwise to the oil phase under a first stirring, and then mixing under a second stirring. Preferably, the rotation speed of the first stirring and the second stirring is independently 1000~2000 rpm; Preferably, the dripping rate is 1~5 mL / min; Preferably, the second stirring time is 10-30 min.

8. A gelatin-based high internal phase emulsion foam material, characterized in that, The gelatin-based high internal phase emulsion foam material is made by curing and drying the gelatin-based high internal phase emulsion as described in any one of claims 1 to 4.

9. The gelatin-based high internal phase emulsion foam material according to claim 8, characterized in that, The curing includes cold curing; Preferably, the temperature for cold storage curing is 0~15℃; Preferably, the cold storage curing time is 10~24 h; Preferably, the curing process further includes an extraction and degreasing step; Preferably, the oil removal process includes oil removal using ethanol; Preferably, the drying includes vacuum drying; Preferably, the vacuum drying temperature is 20~30℃; Preferably, the vacuum drying time is 5 to 20 hours.

10. The application of a gelatin-based high internal phase emulsion foam material as described in claim 8 or 9 in 3D cell culture or daily chemical hygiene products.

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