Biphase drug-loaded Pickering emulsion with stable silk fibroin nanoparticles and antibacterial application of biphase drug-loaded Pickering emulsion

Abstract

The invention belongs to the technical field of functional Pickering emulsion preparation, and particularly discloses a silk fibroin nanoparticle-stabilized biphase drug-loaded Pickering emulsion and an antibacterial application thereof. The curcumin-loaded silk fibroin nanoparticles Cur-SFNPs with uniform form and size are prepared by using an anti-solvent precipitation method. In order to improve the antibacterial effect of the Pickering emulsion, the Cur-SFNPs is utilized to stabilize the soybean oil loaded with resveratrol, and the oil-in-water type Pickering emulsion is prepared. The Pickering emulsion prepared by taking Cur-SFNPs as a stabilizer has the characteristics of small particle size, uniform distribution, storage stability, heating stability, freeze-thaw stability, food safety and environmental friendliness. And as a two-phase drug-loaded emulsion, two natural hydrophobic active drugs are loaded at the same time, so that the solubility and bioavailability of the emulsion can be enhanced, the loaded active substances play a synergistic antibacterial and antioxidant role, and the emulsion can be applied to food preservation.

Description

Technical Field

[0001] The invention belongs to the technical field of functional Pickering emulsion preparation, and specifically discloses a dual-phase drug-loaded Pickering emulsion stabilized by silk fibroin nanoparticles and its antibacterial application. Background Art

[0002] Compared to traditional emulsions, Pickering emulsions offer high stability, low emulsifier usage, and enhanced safety, making them widely used in food, pharmaceuticals, and cosmetics. Solid particles used to stabilize Pickering emulsions include synthetic, inorganic, and organic particles. Synthetic and inorganic particles may present certain biosafety concerns. Consequently, within food-grade Pickering emulsions, researchers are increasingly interested in using natural organic colloidal particles to stabilize emulsions. Protein particles, as natural colloidal particles, have been widely used in Pickering emulsions.

[0003] Silk fibroin, a natural protein extracted from silkworm cocoons, possesses numerous properties due to its unique molecular structure and chemical composition, including biocompatibility, biodegradability, excellent mechanical strength, flexibility, and thermal stability. It also possesses emulsifying, foaming, and gelling properties. As a solid particle stabilizer for Pickering emulsions, SF enhances the texture, stability, and sensory qualities of foods, attracting increasing attention. SF is also being widely explored and applied as a carrier for various bioactive substances.

[0004] Curcumin (Cur) and resveratrol (Res) are natural bioactive substances with antibacterial, anti-inflammatory, and antioxidant properties. However, both are hydrophobic molecules with poor water solubility, instability, and susceptibility to degradation under light, heat, and long-term storage conditions, resulting in low bioavailability. These issues have limited their development and application.

[0005] Existing approaches to address the low bioavailability of natural active pharmaceutical ingredients include nanocarrier delivery systems (nanoparticles, Pickering emulsions, and liposomes), natural macromolecular composite systems, and responsive release strategies. However, existing technologies, when using synthetic surfactants, present certain biosafety issues, and some preparation processes are complex. Furthermore, traditional Pickering emulsions are prone to droplet aggregation during long-term storage, requiring freeze-drying or the addition of stabilizers, which increases costs. Summary of the Invention

[0006] The purpose of the present invention is to provide a dual-phase drug-loaded Pickering emulsion stabilized by silk fibroin nanoparticles (Cur-SFNPs), a preparation method thereof, and application in the antibacterial field.

[0007] Curcumin-silk fibroin nanoparticles (Cur-SFNPs) were first prepared by the antisolvent precipitation method. The nanoparticles were then used as the aqueous phase and soybean oil loaded with resveratrol was used as the oil phase. An emulsion was formed by homogenous shearing. This Pickering emulsion dual-phase drug loading can improve the bioavailability of curcumin and resveratrol. It has the advantages of simple preparation method, high safety, high stability, and good antibacterial properties, and has broad application prospects in the field of food preservation.

[0008] The preparation method of a dual-phase drug-loaded Pickering emulsion with antibacterial properties stabilized by silk fibroin nanoparticles (Cur-SFNPs) comprises the following steps:

[0009] (1) Extraction of SF

[0010] After degumming, the silk was dissolved in 9.3 M LiBr solution and purified by dialysis to obtain the regenerated silk fibroin solution.

[0011] (2) Preparation of curcumin-loaded silk fibroin nanoparticles (Cur-SFNPs)

[0012] Curcumin was dissolved in ethanol, and then the curcumin ethanol solution was injected into the silk fibroin solution according to the volume ratio. When the curcumin solution and the silk fibroin solution were mixed, curcumin-silk fibroin nanoparticles (Cur-SFNPs) were quickly formed.

[0013] The concentration of the curcumin ethanol solution is 0.5-2.5 mg / mL; the volume ratio of the curcumin ethanol solution to the silk fibroin solution is 1:10.

[0014] (3) Preparation of resveratrol-loaded soybean oil

[0015] Resveratrol was added to a solution containing 4% ethanol and 96% soybean oil (v / v), and stirred and ultrasonicated until it was completely dissolved to form an oil phase.

[0016] The concentration of resveratrol in the oil phase was 100-225 μg / mL.

[0017] (4) Preparation of Pickering emulsion

[0018] Cur-SFNPs dispersion was used as the aqueous phase and resveratrol-loaded soybean oil was used as the oil phase. The aqueous phase and the oil phase were then mixed and subjected to high-speed shearing in an ice bath at a speed of 15,000 rpm / min for 4 minutes to obtain a Pickering emulsion stabilized by curcumin-silk fibroin nanoparticles.

[0019] The concentration of silk fibroin in the Cur-SFNPs dispersion as the aqueous phase was 2-18 mg / mL, and the volume ratio of the aqueous phase to the oil phase was 3:7-7:3.

[0020] The beneficial effects of the present invention are:

[0021] (1) The present invention uses all-natural ingredients, no chemical surfactants, and is green and safe. The natural stabilizer, silk fibroin nanoparticles, is used to stabilize the Pickering emulsion, which has the characteristics of high stability, food safety, and environmental friendliness.

[0022] (2) The present invention can improve the loading capacity of hydrophobic active ingredients and enhance their solubility and bioavailability;

[0023] (3) The dual-phase drug delivery method of the present invention, wherein the aqueous phase carries curcumin and the oil phase carries resveratrol, can simultaneously allow the loaded active substances to exert synergistic antibacterial and antioxidant effects, and can be applied to food preservation.

[0024] This study demonstrates the potential of natural food-derived curcumin-silk fibroin nanoparticles (Cur-SFNPs) as Pickering emulsion stabilizers, providing a promising approach to enhance the delivery of hydrophobic bioactive compounds and having broad application prospects in the field of antimicrobial food preservation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The actual picture and particle size distribution diagram of Cur-SFNPs.

[0026] Figure 2 FTIR spectra of SF, Cur-SFNPs and Cur.

[0027] Figure 3 is the encapsulation efficiency of silk fibroin nanoparticles loaded with different concentrations of curcumin.

[0028] Figure 4 Actual photos and microscopic images of Pickering emulsions prepared with different silk fibroin concentrations on day 0 and day 14 (C SF =2-18 mg / mL, soybean oil: 50%).

[0029] Figure 5 Figure 2 shows the particle size changes of Pickering emulsions prepared with different silk fibroin concentrations on day 0 and day 14.

[0030] Figure 6 The physical pictures and micrographs of Pickering emulsions prepared with different oil phase volume ratios (soybean oil: 30%-70%, C SF =10 mg / mL).

[0031] Figure 7 The particle size changes of Pickering emulsions prepared with different oil phase volume ratios on day 0 and day 14.

[0032] Figure 8 This is a photo of Pickering emulsion before and after freeze-thaw.

[0033] Figure 9 Microscopic images of Pickering emulsion before and after freeze-thaw.

[0034] Figure 10 This is a graph showing the change in particle size of the Pickering emulsion droplets before and after freeze-thaw.

[0035] Figure 11 These are the actual pictures of Pickering emulsion before and after heating at 90°C.

[0036] Figure 12 Microscopic images of Pickering emulsion before and after heating at 90°C.

[0037] Figure 13 This is a graph showing the change in particle size of the Pickering emulsion droplets before and after heating at 90°C.

[0038] Figure 14 The colony formation of S. aureus after treatment with different concentrations of Pickering.

[0039] Figure 15 The corresponding quantitative statistical results of S. aureus colonies after being treated with different concentrations of Pickering.

[0040] Figure 16 The colony formation of E. CoLi after treatment with different concentrations of Pickering emulsion.

[0041] Figure 17 These are the quantitative statistical results of E.CoLi colonies treated with different concentrations of Pickering.

[0042] Figure 18 The biofilm inhibition effect of S. aureus after Pickering emulsion treatment.

[0043] Figure 19 The biofilm inhibition effect of E.CoLi after Pickering emulsion treatment.

[0044] Figure 20 The biofilm disruption effect of S. aureus after Pickering emulsion treatment.

[0045] Figure 21 The biofilm destruction effect of E.CoLi after Pickering emulsion treatment.

[0046] Figure 22This is the appearance of strawberries wrapped with Pickering emulsion and stored at 20°C.

[0047] Figure 23 The weight loss of strawberries at different time points during storage.

[0048] Figure 24 This is a physical picture of curcumin and resveratrol co-loaded in the aqueous phase.

[0049] Figure 25 This is the release curve of the Pickering emulsion prepared in Comparative Example 3 in pH 7.4 PBS buffer.

[0050] Figure 26 This is a process flow chart for preparing Pickering emulsion. DETAILED DESCRIPTION

[0051] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the embodiments. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0052] Example 1 Extraction of SF

[0053] (1) Degumming: Weigh 2.12 g of anhydrous sodium carbonate solid and dissolve it in 1 L of deionized water. Add 20 g of cocoons to the solution, cut into pieces, and boil for 30 min. Remove the cocoons, cool them in cold water, rinse them, wring them out, and then tear them apart. Repeat this process four times until all the silk becomes fibrous. Then, dry the silk in an oven.

[0054] (2) Dissolution: Weigh 16.15 g of lithium bromide with weighing paper, dissolve it in a fume hood, and dilute to 20 mL with deionized water. Preheat the LiBr solution on a magnetic stirrer at 60°C, weigh 2.85 g of degummed silk, place it in the solution, and stir until it is completely dissolved to obtain a yellow silk fibroin lithium bromide mixed solution.

[0055] (3) Dialysis: Pour the above solution into a dialysis bag, clamp both ends with clips, and place the dialysis bag in deionized water for 3 days.

[0056] Example 2 Preparation of Cur-SFNPs and its particle size distribution and FITC spectrum

[0057] (1) 1.5 mg of curcumin was dissolved in 10 mL of ethanol, and the curcumin ethanol solution was injected into the silk fibroin solution prepared in Example 1 at a volume ratio of 1:10. When the curcumin solution and the silk fibroin solution were mixed, curcumin-silk fibroin nanoparticles (Cur-SFNPs) were rapidly formed.

[0058] (2) The SF solution obtained in Example 1 and the Cur-SFNPs were freeze-dried using a freeze dryer and then detected using an infrared spectrometer.

[0059] The size distribution and PDI of Cur-SFNPs were detected by MaLvern Zetasizer Nano analyzer. Figure 1 As shown in the attached figure, the average droplet size of Cur-SFNPs is about 207 nm and the PDI is 0.173. Figure 2 As shown, compared with pure curcumin (Cur) and pure SF, in Cur-SFNPs nanoparticles, 3506 cm -1 The phenolic hydroxyl groups at the position of silk fibroin moved to lower wavenumbers, which may be due to the formation of hydrogen bonds by the phenolic hydroxyl groups. The changes in the peak positions of the amide I and amide III bands of silk fibroin indicate changes in its secondary structure, indicating that the loading was successful.

[0060] Example 3 Effect of different curcumin concentrations on nanoparticle encapsulation efficiency

[0061] (1) 0.5 mg, 1 mg, 1.5 mg, 2 mg, and 2.5 mg of curcumin were dissolved in 10 mL of ethanol, respectively. The curcumin ethanol solution was injected into the silk fibroin solution of Example 1 at a volume ratio of 1:10. When the curcumin solution and the silk fibroin solution were mixed, curcumin-silk fibroin nanoparticles (Cur-SFNPs) were rapidly formed, and Cur-SFNPs with final curcumin concentrations of 45, 91, 136, 181, and 227 μg / mL were obtained.

[0062] (2) Take 2 mL of the above-mentioned Cur-SFNPs nanoparticle solution with different concentrations, add 2 mL of anhydrous ethanol solution, sonicate for 20 min, centrifuge at 8000 rpm for 10 min, take the supernatant and dilute it, and measure its absorbance using a UV spectrophotometer.

[0063] As attached Figure 3 As shown in the figure, when the concentration of curcumin is 1.5 mg / mL, the encapsulation efficiency of silk fibroin solution is the highest, which can reach 94%.

[0064] Example 4 Effect of different SF concentrations on Pickering emulsion formation

[0065] (1) Preparation of Cur-SFNPs: The silk fibroin solution obtained in Example 1 was diluted with a lithium bromide mixed solution to a concentration of 2, 6, 10, 14, and 18 mg / mL. A 1.5 mg / mL curcumin ethanol solution was injected into the silk fibroin solutions of different concentrations at a volume ratio of 1:10, and the mixture was stirred at 300 rpm to obtain Cur-SFNPs.

[0066] (2) Preparation of Pickering emulsion: Cur-SFNPs dispersions with different silk fibroin concentrations were used as the aqueous phase and pure soybean oil as the oil phase (water-oil ratio of 1:1). The mixture was homogenized using a homogenizer under an ice bath at a speed of 15,000 rpm / min for 4 min.

[0067] The prepared Pickering emulsions were stored at room temperature. Images of all scales were collected on day 0 and day 14 to visually assess storage stability. The average droplet size and distribution of the Pickering emulsions were further analyzed using a 20× inverted fluorescence microscope. The actual images and average droplet size and distribution of the Pickering emulsions at silk fibroin concentrations of 2-18 mg / mL are shown in the attached figure. Figure 4 As shown in Figure 2, phase separation is negatively correlated with the concentration of silk fibroin. Figure 5 As shown, the size of all emulsion droplets increased after 14 days, among which the emulsion with a silk fibroin concentration of 10 mg / mL had the smallest particle size and the least particle size growth, indicating it was the most stable.

[0068] Example 5 Effect of different oil ratios on Pickering emulsion formation

[0069] (1) Preparation of Cur-SFNPs: The silk fibroin solution obtained in Example 1 was diluted with a lithium bromide mixed solution to a concentration of 10 mg / mL, and a 1.5 mg / mL curcumin ethanol solution was injected into the silk fibroin solution at a volume ratio of 1:10. The mixture was stirred at 300 rpm to obtain Cur-SFNPs.

[0070] (2) Preparation of Pickering emulsion: Cur-SFNPs dispersion with a silk fibroin concentration of 10 mg / mL was used as the aqueous phase, and pure soybean oil was used as the oil phase (water / oil volume ratio of 3:7, 4:6, 5:5, 6:4, 7:3). The mixture was homogenized using a homogenizer under an ice bath at a speed of 15,000 rpm / min for 4 min.

[0071] The prepared Pickering emulsions were stored at room temperature. Images of all ratios were collected on day 0 and day 14 to visually assess storage stability. The average droplet size and distribution of the Pickering emulsions were further analyzed using a 20× inverted fluorescence microscope. The average droplet size and distribution of the Pickering emulsions prepared with water / oil volume ratios of 3:7, 4:6, 5:5, 6:4, and 7:3 are shown in the attached figure. Figure 6 As shown in the figure, as the volume ratio of the oil phase increases, the yellow color of the emulsion changes from dark to light. Figure 7As shown in the figure, on day 0, the droplet size of the emulsions increased with the oil phase increasing from 30% to 70%. After 14 days, the droplet size of all emulsion groups changed, but the droplet size of the emulsion with 50% soybean oil showed the smallest change, indicating that the emulsion has good storage stability.

[0072] Example 6 Physical stability evaluation of the prepared Pickering emulsion

[0073] (1) Heating stability: Pickering emulsions with different water-oil ratios (water / oil volume ratios of 3:7, 4:6, 5:5, 6:4, and 7:3) prepared in fresh Example 5 were heated at 95°C for 30 min and then returned to room temperature. The actual images of the emulsions before and after heating, as well as the average droplet size and distribution of the emulsions are shown in the attached figure. Figure 8 、 9 The thermal stability of the emulsion was evaluated by the change in particle size of the emulsion droplets before and after heating. Figure 10 As shown in the figure, no obvious change in the droplet size of each group of emulsions was observed with increasing temperature, indicating that the emulsions have good heating stability.

[0074] (2) Freeze-thaw stability: Fresh Pickering emulsions prepared in Example 5 with different water-oil ratios (water / oil volume ratios of 3:7, 4:6, 5:5, 6:4, and 7:3) were placed at -20°C for 24 hours and then taken out and returned to room temperature. The actual pictures of the emulsions before and after freeze-thaw as well as the average droplet size and distribution of the emulsions are shown in the attached figure. Figure 11 、 12 The freeze-thaw stability of the emulsion was evaluated by the change in particle size of the emulsion droplets before and after freezing and thawing. Figure 13 As shown in the figure, after freeze-thaw, the particle size of each group of emulsion droplets increased slightly, indicating that the emulsion has good freeze-thaw stability.

[0075] Example 7 Antibacterial activity of curcumin (Cur) and resveratrol (Res) alone

[0076] The antibacterial activity test method is the same as that in Example 8.

[0077]

[0078] In vitro antibacterial activity test of the dual-phase drug-loaded Pickering emulsion prepared in Example 8

[0079] Preparation of biphasic drug-loaded Pickering emulsion

[0080] Resveratrol was added to a solution containing 4% ethanol and 96% soybean oil (v / v), stirred and ultrasonicated until it was completely dissolved to obtain oil phases with resveratrol concentrations of 0, 100, 150, and 225 μg / mL. The Cur-SFNPs dispersion was used as the aqueous phase, and the above-mentioned resveratrol-loaded soybean oil was used as the oil phase (water-oil volume ratio of 1:1). The conditions were: in an ice bath environment, a rotation speed of 15,000 rpm / min, and a time of 4 minutes. After high-speed shearing, a Pickering emulsion stabilized by curcumin-silk fibroin nanoparticles was obtained.

[0081] 1. In vitro antibacterial test of Pickering emulsion (solid agar plate colony counting method)

[0082] In order to investigate the effect of Pickering emulsion on the survival rate of S. aureus, the S. aureus bacterial solution in the logarithmic growth phase was diluted to 1×10 8 CFU / mL was incubated with Pickering emulsion on a shaker (250 rpm, 37°C) for 90 min. PBS was used as a negative control group. The volume ratio of bacterial solution to Pickering emulsion was 1:3. The sample after incubation was diluted to 2×10 4 Take 100 μL and drop it onto the solid agar plate, spread it evenly with a coating bead, and place it in a biochemical incubator for overnight culture. Take it out the next day, count and photograph the colonies on the agar plate, compare it with the PBS group, and calculate the bacterial survival rate. Set up 3 parallel samples for each group. Figure 14 and attached Figure 15 As shown, the number of colonies in the Pickering emulsion group decreased in a concentration-dependent manner compared to the control group (PBS group). When the concentration of resveratrol was 225 μg / mL, the survival rate of S. aureus was only 13%.

[0083] In order to explore the effect of Pickering emulsion on E.coLi, the E.coLi bacterial solution in the logarithmic growth phase was diluted to 1×10 8 CFU / mL and Pickering emulsion were placed on a shaker (250 rpm, 37 ° C) and incubated for 90 min. PBS was used as a negative control group. The post-treatment process was the same as above. Figure 16 and attached Figure 17 As shown in the figure, the number of colonies in the Pickering emulsion group was significantly reduced compared to the control group. When the resveratrol concentration was 225 μg / mL, the survival rate of E. coLi was 24%. Therefore, the resveratrol concentration was 225 μg / mL for subsequent experiments.

[0084] 2. Experiment on inhibition and destruction of biofilm by Pickering emulsion

[0085] (1) Experiment on the inhibition of biofilm by Pickering emulsion

[0086] For biofilm inhibition studies, 150 μL Pickering emulsion (resveratrol concentration 225 μg / mL) was added to a 96-well plate, and 50 μL of S. aureus and E. coLi solutions (1×10 8 CFU / mL). The plate was placed in an incubator for 48 hours, and then 100 μL of crystal violet was added to stain the biofilm. The crystal violet in the biofilm was then dissolved in 200 μL of 80% ethanol in a constant temperature shaker for 2 hours (250 rpm, 37°C), and the absorbance at 600 nm was measured using a microplate reader. Figure 18 As shown in Figure 2, S. aureus formed only 24% of the biofilm when incubated with Pickering emulsion. Figure 19 As shown, E. coLi formed 41% biofilm when incubated with Pickering emulsion.

[0087] (2) Experiment on the destruction of biofilm by Pickering emulsion

[0088] For biofilm disruption studies, 96-well plates were first loaded with 100 μL of the corresponding culture medium and 100 μL of S. aureus and E. coli solutions (1 × 10 8 CFU / mL). The plate was placed in an incubator for 48 hours, after which the supernatant was discarded and 200 μL of Pickering emulsion (resveratrol concentration 225 μg / mL) was added and returned to the incubator for another 90 minutes. The biofilm was then stained with 100 μL of crystal violet instead of the culture medium. The crystal violet in the biofilm was then dissolved in 200 μL of 80% ethanol in a thermostatic shaker for 2 hours (250 rpm, 37°C), and the absorbance at 600 nm was measured using a microplate reader. Figure 20 As shown in Figure 2, after 90 min of incubation with Pickering emulsion, only 23% of the biofilm formed by S. aureus remained. Figure 21 As shown, after 90 min of incubation with Pickering emulsion, 53% of the biofilm formed by E. coLi was retained.

[0089] Example 9: Use of Pickering emulsion for fruit preservation

[0090] Strawberries with uniform size and shape, no defects, and a surface color of 90% red were selected to evaluate the effects of Pickering emulsion (resveratrol concentration 225 μg / mL) on their quality, freshness, and surface bacterial growth. Each group of strawberries (n=3) was immersed in the dipping dispersion for 3 minutes and then air-dried in a fume hood at room temperature until no drips appeared on the strawberries' surface. Untreated strawberries served as controls. Both groups of strawberries were placed in plastic containers and stored at 20°C. The strawberries were weighed on each monitoring day, and the mass loss rate was expressed as the ratio of the fruit mass reduced on that day to the initial mass.

[0091] Comparative Example 1

[0092] (1) Preparation of Cur: The silk fibroin solution obtained in Example 1 was diluted to a concentration of 10 mg / mL and stirred at 300 rpm to obtain Cur.

[0093] (2) adding resveratrol to a solution containing 4% ethanol and 96% soybean oil (v / v), stirring and ultrasonicating until it is completely dissolved; obtaining a resveratrol oil phase with a concentration of 225 μg / mL;

[0094] (3) Preparation of Pickering emulsion: Cur dispersion was used as the aqueous phase and resveratrol-loaded soybean oil was used as the oil phase (water-oil ratio 1:1). The mixture was homogenized using a homogenizer under an ice bath at a speed of 15,000 rpm / min for 4 min.

[0095] Comparative Example 2

[0096] 1.5 mg of curcumin and resveratrol (the concentration of resveratrol in ethanol is 225 μg / mL) were dissolved in 10 mL of ethanol. The curcumin and resveratrol ethanol solutions were injected into the silk fibroin solution at a volume ratio of 1:10. When the curcumin solution and the silk fibroin solution were mixed, curcumin-resveratrol-silk fibroin nanoparticles were quickly formed. When curcumin and resveratrol were co-loaded in the aqueous phase, the prepared nanoparticles were unstable and drug precipitation occurred. Figure 24 shown.

[0097] Comparative Example 3

[0098] 1.5 mg of curcumin and resveratrol (resveratrol concentration in the oil phase is 225 μg / mL) were added to the oil phase containing 4% ethanol and 96% soybean oil (v / v), stirred and ultrasonicated until they were completely dissolved, and then high-speed sheared at 15000 rpm / min for 4 min in an ice bath to obtain a curcumin-resveratrol Pickering emulsion. Co-loading curcumin and resveratrol in the oil phase makes it difficult to coordinate the release sequence of the drugs, such as Figure 25 shown.

Claims

1. A dual-phase drug-loaded Pickering emulsion stabilized by silk fibroin nanoparticles, characterized in that: The Pickering emulsion comprises a water phase of curcumin-loaded silk fibroin nanoparticles Cur-SFNPs and a oil phase of resveratrol-loaded soybean oil, which are obtained by high-speed shearing in a homogenizer.

2. A method for preparing the dual-phase drug-loaded Pickering emulsion stabilized by silk fibroin nanoparticles according to claim 1, characterized in that: The preparation method of the Pickering emulsion comprises the following steps: (1) Preparation of curcumin-loaded silk fibroin nanoparticles Cur-SFNPs Dissolve curcumin in ethanol, and then inject the curcumin ethanol solution into the silk fibroin solution to form a curcumin-silk fibroin nanoparticle Cur-SFNPs dispersion; (2) Preparation of resveratrol-loaded soybean oil Resveratrol was added to a solution containing 4% ethanol and 96% soybean oil, and stirred and ultrasonicated until it was completely dissolved to form an oil phase; (3) Preparation of Pickering emulsion The Cur-SFNPs dispersion as the aqueous phase was mixed with the oil phase, and a Pickering emulsion stabilized by curcumin-silk fibroin nanoparticles was obtained after high-speed shearing in an ice bath environment.

3. The method for preparing a dual-phase drug-loaded Pickering emulsion stabilized by silk fibroin nanoparticles according to claim 2, characterized in that: The concentration of the curcumin ethanol solution in step (1) is 0.5-2.5 mg / mL; the volume ratio of the curcumin ethanol solution to the silk fibroin solution is 1:

10.

4. The method for preparing a dual-phase drug-loaded Pickering emulsion stabilized by silk fibroin nanoparticles according to claim 2, characterized in that: The concentration of resveratrol in the oil phase in step (2) is 100-225 μg / mL.

5. The method for preparing a dual-phase drug-loaded Pickering emulsion stabilized by silk fibroin nanoparticles according to claim 2, characterized in that: The concentration of silk fibroin in the Cur-SFNPs dispersion as the aqueous phase in step (3) is 2-18 mg / mL, and the volume ratio of the aqueous phase to the oil phase is 3:7-7:

3.

6. The method for preparing a dual-phase drug-loaded Pickering emulsion stabilized by silk fibroin nanoparticles according to claim 2, characterized in that: The high-speed shearing in step (3) uses a homogenizer with a rotation speed of 15000 rpm / min and a time of 4 min.

7. A use of the silk fibroin nanoparticle-stabilized dual-phase drug-loaded Pickering emulsion according to claim 1, characterized in that: The Pickering emulsion is used for preparing antibacterial materials.

8. The use of the silk fibroin nanoparticle-stabilized dual-phase drug-loaded Pickering emulsion according to claim 7, characterized in that: The antibacterial material is used for in vitro sterilization of S. aureus and E. coli, or for preserving fruits.

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