A phase change eutectic carrier embedded with photothermal agents, and a preparation method and application thereof

Abstract

The present application relates to the technical field of pesticides, and discloses a phase change eutectic carrier embedded with a photothermal agent as well as a preparation method and application thereof.The phase change eutectic carrier embedded with the photothermal agent mainly comprises a photothermal agent, a fatty acid, an organic solvent and water.The preparation process of the preparation is simple, the conditions are mild, a large number of additives are not needed, and the preparation can be quantitatively prepared.The dispersion and utilization rate of the bactericide can be improved through eutectic, and the effectiveness of the bactericide can be improved.The preparation is suitable for various application modes such as seed coating and soil treatment, can play various synergistic functions such as temperature response release, prolonging drug retention time, enhancing adhesion and permeability on the surface of pathogenic bacteria, and is a kind of green and efficient bactericide dosage form, which has a wide application prospect in green and intelligent agriculture.

Description

Technical Field

[0001] This invention relates to the field of pesticide technology, and in particular to a phase change eutectic carrier with embedded photothermal agent, its preparation method and application. Background Technology

[0002] Soil-borne diseases are caused by pathogens such as fungi, bacteria, nematodes, and viruses that live in the soil with diseased plant debris and infect crops through the roots or stems when conditions are suitable. Fungi are the most prevalent, such as *Pythium spp.* causing seedling rot and damping-off, *Rhizoctonia solani* causing seedling blight, and *Fusarium oxysporum* and *Verticillium alboatum* causing wilting and death. Soil-borne diseases cause significant economic losses to agricultural production due to their rapid onset and limited control methods. Currently, chemical fungicides remain the primary control strategy for soil-borne diseases, with mainstream fungicides including copper-based fungicides, organosulfur fungicides, triazole fungicides, methoxyacrylate fungicides, and benzimidazole fungicides. However, the aforementioned fungicides are poorly soluble in water and require the addition of various adjuvants and organic solvents, and are processed through special processes to form wettable powders (WP), suspension concentrates (SC), emulsifiable concentrates (EC), etc. The environmental pollution and ecotoxicity caused by chemically synthesized adjuvants (such as surfactants and thickeners) and solvents (such as toluene and xylene) cannot be ignored. Therefore, the development of green and efficient pesticide delivery systems (PDS) has become a research hotspot in the field of pesticide formulation.

[0003] Phase change materials (PCMs) are materials that undergo solid-liquid and liquid-solid phase transitions under external temperature stimuli. Due to their temperature sensitivity, they have been extensively studied in drug delivery. Eutectic melting is a common phenomenon in solid-state systems, referring to a mixture of different substances (usually two or more components) that melts at its lowest melting point at a specific temperature, with all components simultaneously initiating melting at that temperature. Using PCMs as pesticide carriers can achieve functionalities such as pesticide stabilization, temperature-responsive release, and controlled release. Therefore, PCM carriers hold great promise for applications in pesticide "reduction and efficiency enhancement." Summary of the Invention

[0004] The purpose of this invention is to provide a phase change eutectic carrier with embedded photothermal agent, its preparation method, and its application. The preparation method of this invention is simple and mild, ensuring 100% retention of the active drug within the carrier during preparation, and allowing for uniform dispersion within the carrier, facilitating storage and transportation. This formulation is simple, green, and safe, and possesses temperature-responsive controlled-release properties; the fungicide active ingredient and the carrier synergistically exert antibacterial effects. It is particularly suitable for use in seed coating, soil treatment, and other methods to achieve the effect of reducing fungicide dosage while increasing efficacy.

[0005] The solution of the present invention is:

[0006] This invention provides a phase change eutectic carrier with an embedded photothermal agent, comprising a photothermal agent, a phase change eutectic material, a pesticide fungicide, an organic solvent, and water;

[0007] The photothermal agent is one of the following: black phosphorus, bifunctional phase change materials, metal nanomaterials, metal oxides, transition metal dichalcogenides (TMDs), MXenes (two-dimensional transition metal carbides or nitrides), carbon-based materials, polydopamine, and polydopamine-metal ion complexes, wherein the metal ion is Cu. 2+ Ti 4+ Zn 2+ Mg 2+ Fe 3+ / Fe 2+ Co 2+ Au 3+ Al 3+ and Ag + One of them.

[0008] As a preferred technical solution, the photothermal agent is polydopamine-metal ion complex (Cu-PDA).

[0009] As a preferred technical solution, the metal ion is Cu. 2+ .

[0010] The photothermal agent has the following morphology: porous material, microcapsule, nanocrystal, nanotube, liposome, nanoparticle, and nanobottle; the mass fraction of the photothermal agent in the phase change eutectic carrier with embedded photothermal agent is 1% to 30%.

[0011] Nanobottles are a preferred technical solution.

[0012] According to an embodiment of the present invention, the morphology of the nanobottle is as follows: Figure 2 As shown.

[0013] As a preferred technical solution, the diameter and mouth size of the nanobottle are in the nanometer range, with the diameter of the nanobottle being 600-700 nm and the mouth size being 120-320 nm.

[0014] As a preferred technical solution, the phase change eutectic material is a fatty acid, which is one of lauric acid, caprylic acid, capric acid, myristic acid, nonanoic acid, palmitic acid and stearic acid; the mass fraction of fatty acid in the phase change eutectic carrier with embedded photothermal agent is 10% to 60%.

[0015] As a preferred technical solution, the phase change eutectic material further includes an organic solvent and water, wherein the organic solvent is one of ethanol, N-methylpyrrolidone, N,N-dimethylformamide, 2-pyrrolidone and dimethyl sulfoxide; the mass fraction of the organic solvent in the phase change eutectic carrier with embedded photothermal agent is 20% to 40%, and the balance is water.

[0016] The present invention also discloses a method for preparing a phase change eutectic carrier with embedded photothermal agent, wherein the photothermal agent is mixed with fatty acid and dispersed in an organic solvent, and then the mixture is mixed with water to form a eutectic to obtain the phase change eutectic carrier with embedded photothermal agent.

[0017] As a preferred technical solution, the photothermal agent is a polydopamine-metal ion complex nanobottle. The polydopamine-metal ion complex nanobottle is prepared by solution oxidation of dopamine and metal ions to obtain a polydopamine-metal ion complex shell, and then prepared by swelling-etching method to obtain a nanobottle with a single opening.

[0018] As a preferred technical solution, the preparation of the polydopamine-metal ion complex nanobottle is as follows:

[0019] 1) Preparation of polydopamine-metal ion complex shell by solution oxidation method: Dopamine hydrochloride and metal ion compound were added to Tris buffer containing PS template microspheres, stirred to form polydopamine-metal ion complex, and the lower layer product was collected by centrifugation.

[0020] 2) Swelling: Under room temperature shaking conditions, the polydopamine-metal ion complex obtained above was added to the PS mixed solution, and the lower layer product was collected by centrifugation.

[0021] 3) Etching: Under room temperature oscillation conditions, the product collected in step 2) is added to a good solvent for PS template microspheres, and the lower layer product is collected by centrifugation to obtain polydopamine-metal ion complex nanobottles.

[0022] As a preferred technical solution, in step 1), the mass ratio of dopamine hydrochloride to metal ion compound is 2-5:1; the content of PS template microspheres is 0.125% w / v; the stirring speed is 300-1200 rpm, and the stirring time is 8-24 h.

[0023] In step 2), the PS mixed solution includes a good solvent and water, and the volume ratio of the good solvent to water is 1:2 to 9; the good solvent is one of toluene, benzene, xylene, dichloromethane, chloroform, carbon tetrachloride, tetrahydrofuran, acetone and ethyl acetate; the oscillation in step 2) is a vigorous oscillation with a rotation speed of 200 to 400 rpm.

[0024] As a preferred technical solution, the mass ratio of dopamine hydrochloride to the metal ion compound is 3:1.

[0025] As a preferred technical solution, in 1), the stirring speed is 500-900 rpm and the stirring time is 12 hours.

[0026] As a preferred technical solution, the volume ratio of good solvent to water in step 2) can be 1:4.

[0027] As a preferred technical solution, the oscillation speed in step 2) is 300 rpm.

[0028] As a preferred technical solution, the good solvent in step 3) is one of toluene, tetrahydrofuran, and xylene; the oscillation in step 3) is a vigorous oscillation with a rotation speed of 200-400 rpm.

[0029] As a preferred technical solution, the oscillation speed in step 3) is 300 rpm.

[0030] As a preferred technical solution, the nanobottle is a Cu-PDA nanobottle, which is prepared by solution oxidation of dopamine and copper chloride to obtain a Cu-PDA shell, and then prepared by swelling-etching method to obtain a nanobottle with a single opening.

[0031] As a preferred technical solution, the nanobottle is a Cu-PDA nanobottle, and its preparation process includes the following steps:

[0032] (1) Preparation of Cu-PDA shell by solution oxidation: Dopamine hydrochloride and copper chloride were added to a 10×10 solution containing 0.125% (w / v) PS. -3 In a Tris-HCl buffer solution of pH 8.5, stir to form Cu-PDA@PS, and collect the lower layer product by centrifugation.

[0033] (2) Swelling of Cu-PDA@PS: Under room temperature shaking conditions, the Cu-PDA@PS obtained above was added to a 1% toluene emulsion containing 1% Tween-20 to obtain Janus Cu-PDA@PS, and the lower layer product was collected by centrifugation.

[0034] (3) Janus Cu-PDA@PS etching: Under room temperature oscillation conditions, the Janus Cu-PDA@PS obtained above was added to tetrahydrofuran, and the lower layer product was collected by centrifugation to obtain Cu-PDA nanobottles.

[0035] This invention also provides an application of nano-bottles as a carrier for bactericides.

[0036] The present invention also provides a bactericide carrier, wherein the bactericide carrier contains the above-mentioned Cu-PDA nanobottle.

[0037] The present invention also provides a phase change eutectic carrier, wherein the above-mentioned Cu-PDA nanobottle is embedded in the phase change eutectic carrier.

[0038] This invention also discloses the application of a phase change eutectic carrier with embedded photothermal agent as a carrier for fungicides in crops, for example, in the control of soil-borne diseases. Application methods include seed coating, soil treatment, etc., in agriculture.

[0039] As a preferred technical solution, the phase change eutectic carrier eutectic is a mixture of fatty acids, organic solvents and water.

[0040] As a preferred technical solution, the fatty acid is lauric acid; the mass fraction of the fatty acid in the phase change eutectic carrier with embedded photothermal agent is 10%.

[0041] As a preferred technical solution, the fungicide is one or more of the following: azoxystrobin, fenpropathrin, fludioxonil, metalaxyl, chlorothalonil, oxadixyl, and imazalil.

[0042] As a preferred technical solution, the fungicide is azoxystrobin (AZOX).

[0043] As a preferred technical solution, the organic solvent is ethanol.

[0044] As a preferred technical solution, the fatty acid in the phase change eutectic material is lauric acid, the organic solvent is ethanol, the mass fraction of lauric acid in the phase change eutectic material is 10%, the mass fraction of ethanol in the phase change eutectic material is 27.5%, the mass fraction of water in the phase change eutectic material is 62.5%, and the amount of photothermal agent added is 3% of the total weight of the phase change eutectic material.

[0045] As a preferred technical solution, the loading amount of bactericide in the phase change eutectic carrier with embedded photothermal agent is 10-500 mg / g;

[0046] As a preferred technical solution, the loading of AZOX in the phase change eutectic carrier with embedded photothermal agent is 30 mg / g.

[0047] As a preferred technical solution, the concentration of the photothermal agent in the phase change eutectic carrier with embedded photothermal agent is 10-100 mg / L.

[0048] As a preferred technical solution, the concentration of Cu-PDA nanobottles in the phase change eutectic carrier with embedded photothermal agent is 30 mg / g.

[0049] As a preferred technical solution, the concentration of the bactericide encapsulated in the photothermal agent in the phase change eutectic carrier with embedded photothermal agent is 0.01-5 g / g;

[0050] As a preferred technical solution, the concentration of the bactericide encapsulated in the photothermal agent in the phase change eutectic carrier with embedded photothermal agent is 0.01-1 g / g.

[0051] As a preferred technical solution, the concentration of AZOX encapsulated in Cu-PDA nanobottles is 0.02 g / g.

[0052] This invention also provides a method for preparing a phase change eutectic bactericide with an embedded photothermal agent, comprising the following steps:

[0053] (1) Mix the bactericide and good solvent with the above-mentioned photothermal agent.

[0054] The bactericide and photothermal agent can be selected as described above. For example, azoxystrobin is dissolved in ethyl acetate to form a saturated solution of azoxystrobin; then the Cu-PDA nanobottle is dispersed in the saturated solution of azoxystrobin, shaken thoroughly, and placed in a vacuum environment to obtain a drug-loaded nanobottle.

[0055] (2) Drug loading on phase change eutectic carrier

[0056] The bactericide, saturated fatty acid, and organic solvent are selected as described above. For example, lauric acid is dissolved in ethanol, and then the above-mentioned drug-loaded nanobottle is dispersed in the lauric acid / ethanol solution, shaken thoroughly, and then deionized water is added to obtain a phase change eutectic bactericide with embedded photothermal agent.

[0057] This invention also discloses a phase change eutectic carrier with embedded photothermal agent, its preparation method, and its application. The photothermal material and the phase change eutectic material serve as the phase change eutectic carrier with embedded photothermal agent, loading a pesticide fungicide. The photothermal material is a photothermal agent, which is one of the following: black phosphorus, bifunctional phase change material, metal nanomaterial, metal oxide, transition metal disulfide, two-dimensional transition metal carbide, two-dimensional transition metal carbide nitride, carbon-based material, polydopamine, and polydopamine-metal ion complex. The metal ion in the polydopamine-metal ion complex is Cu. 2+ Ti 4+ Zn 2+ Mg 2+ Fe 3+ Fe 2+ Co 2+ Au 3+ Al 3+ With Ag + One of them.

[0058] Advantages of this invention:

[0059] (1) This invention uses different photothermal agents as temperature-responsive drug release switches. The fungicide is loaded into the photothermal agent and eutectic mixture via adsorption and eutectic loading, and prepared as a phase change eutectic fungicide with embedded photothermal agent in a one-pot process. Eutectic loading improves the loading capacity and dispersibility of the fungicide, achieving temperature-responsive release. Cu-PDA and fatty acids have broad-spectrum antibacterial properties and can synergistically combat soil-borne plant diseases with chemical fungicides, achieving the beneficial effect of "reduced dosage and increased efficiency" in pesticide use.

[0060] (2) The phase change eutectic bactericide with embedded photothermal agent provided by this invention can control the eutectic state of fatty acid and bactericide by simply changing the mass fraction of fatty acid / organic solvent / water. Eutectic melting significantly improves the dispersibility and loading capacity of the bactericide in the carrier; based on the eutectic material's ability to operate above the phase change temperature (T... m When the solid phase transforms into the liquid phase, the system exhibits temperature responsiveness. By changing the temperature, the bactericide can be released in a cascade manner, that is, the bactericide fixed in the eutectic is released first, and the bactericide loaded in the photothermal agent is released later.

[0061] (3) The phase change eutectic bactericide with embedded photothermal agent provided by this invention is solid and has a relatively large size under low temperature and cloudy conditions, which can effectively seal the drug in the carrier and confine it to the soil surface, preventing the loss of active ingredients; under high temperature and sunny conditions, a solid-liquid phase transition occurs to release the bactericide, which is transported downwards to act on the crop roots. At the same time, as the soil layer deepens, the temperature gradually decreases, the carrier undergoes a liquid-solid transition, confining the bactericide to the soil layer around the crop roots, prolonging the action time, improving the bactericide's effect, and preventing it from flowing into groundwater.

[0062] (4) Compared with traditional fungicide formulations (WP, SC), the phase change eutectic fungicide with embedded photothermal agent used in this invention has the advantages of simple preparation process, mild conditions, no need for a large number of adjuvants, quantitative preparation, low energy consumption, low organic solvent content, no loss of active ingredient, and significantly reduced pesticide loss into the environment during use. The phase change eutectic fungicide with embedded photothermal agent can improve the dispersibility and utilization rate of the active ingredient, and is suitable for various application methods such as seed coating and soil treatment. It can play a variety of synergistic functions depending on the application environment, and is a type of green and efficient fungicide carrier. Attached Figure Description

[0063] Figure 1 This is a schematic diagram illustrating the preparation process of the Cu-PDA nanobottle containing the photothermal agent and the fabrication process of the phase change eutectic bactericide with embedded photothermal agent in Example 1 of the present invention.

[0064] Figure 2 The images shown are scanning electron microscope (SEM) and transmission electron microscope (TEM) images of the Cu-PDA nanobottle, a photothermal agent, in Example 1 of this invention.

[0065] Figure 3The loading rate and drug loading of pyraclostrobin in the Cu-PDA nanobottle of photothermal agent in Example 1 of this invention are shown.

[0066] Figure 4 This is the phase diagram of the eutectic region of lauric acid-ethanol-water in Example 1 of the present invention.

[0067] Figure 5 These are eutectic mixtures of lauric acid, ethanol, and water in different phases, as described in Example 1 of this invention.

[0068] Figure 6 This is a scanning electron microscope image of the phase change eutectic bactericide with embedded photothermal agent prepared in Example 1 of the present invention.

[0069] Figure 7 The cumulative release curve of azoxystrobin in the phase change eutectic bactericide with embedded photothermal agent in Example 1 of the present invention is shown.

[0070] Figure 8 The photothermal conversion performance of the phase change eutectic carrier with embedded photothermal agent in Embodiment 1 of the present invention.

[0071] Figure 9 This shows the phase transition of the phase change eutectic carrier with embedded photothermal agent in Embodiment 1 of the present invention under light irradiation.

[0072] Figure 10 The phase change eutectic bactericide with embedded photothermal agent in Example 1 of this invention is shown to control cotton Verticillium wilt.

[0073] Figure 11 This describes the effect of the phase change eutectic bactericide with embedded photothermal agent in Example 1 of the present invention on cotton germination and growth.

[0074] Figure 12 This describes the effect of the phase change eutectic bactericide with embedded photothermal agent in Example 1 of the present invention on the abundance of soil microbial populations. Detailed Implementation

[0075] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific embodiments.

[0076] Unless otherwise stated, all raw materials and reagents used in the following examples are chemically pure, commercially available, and from no specific manufacturer. Alternatively, they can be prepared using known methods.

[0077] Example 1

[0078] In this embodiment, the photothermal agent is a Cu-PDA nanobottle, and the phase change eutectic carrier eutectic is a mixture of fatty acids, organic solvents, and water.

[0079] according to Figure 1The process flow shown is used to prepare Cu-PDA nanobottles and phase change eutectic bactericides with embedded photothermal agents:

[0080] First, take 0.5 mL of polystyrene microsphere aqueous suspension (2.5%, w / v), wash twice with water, and collect by centrifugation as a reaction template.

[0081] The second step is to disperse the collected PS template in 10 mL of solution containing 1 mg / mL. -1 The dopamine hydrochloride was added to a Tris-HCl buffer (10 mM, pH 8.5), and 3 mg of copper chloride was added. The reaction was carried out at room temperature for 12 hours, and the solid product was collected by centrifugation at 6000 rpm for 5 min. The operation was repeated twice to obtain PS@Cu-PDA core-shell particles.

[0082] In the third step, the obtained PS@Cu-PDA core-shell particles were added to 10 mL of a 1% toluene emulsion containing 1% Tween-20, and then incubated on a shaker at 300 rpm at room temperature for 8 h to allow the PS polystyrene microspheres to swell. After the reaction was complete, 20 mL of anhydrous ethanol was added to quench the swelling, and the solid product was collected by centrifugation at 6000 rpm for 5 min and washed three times with ethanol. The obtained product was then incubated with 10 mL of THF on a shaker at 300 rpm at room temperature for 4 h to dissolve all the PS. After the reaction was complete, the product was washed twice with THF and centrifuged to obtain Cu-PDA nanobottles.

[0083] Fourth step: Azoxystrobin is dissolved in ethyl acetate to form AZOX solutions of different concentrations. Then, the Cu-PDA nanobottle is dispersed in the above solutions, shaken thoroughly, and placed in a vacuum environment for 6 hours to obtain drug-loaded nanobottles.

[0084] In the fifth step, lauric acid was dissolved in ethanol (0.3 mg / mL), and then the above-mentioned drug-loaded nanobottle was dispersed in the lauric acid / ethanol solution. After thorough shaking, deionized water was added to encapsulate the drug-loaded nanobottle and allow the lauric acid, ethanol, and water to co-melt, thus solidifying the free azoxystrobin and obtaining a phase change eutectic fungicide with an embedded photothermal agent loaded with azoxystrobin, hereinafter referred to as ANT. This was used for subsequent experimental verification.

[0085] 1) Example 1: Drug loading experiment in Cu-PDA nanobottles

[0086] First, prepare a 0.1 mg / mL azoxystrobin / methanol solution in a 25 mL volumetric flask. Pipette 5 mL, 2.5 mL, 0.5 mL, 0.25 mL, 0.05 mL, and 0.025 mL into 50 mL volumetric flasks and dilute to volume with methanol. Establish a standard curve for azoxystrobin using high-performance liquid chromatography (HPLC).

[0087] The second step involves determining the concentration of azoxystrobin encapsulated in the obtained drug-loaded nanobottles using liquid chromatography, and then calculating the encapsulation efficiency of azoxystrobin in the nanobottles. The encapsulation efficiency of azoxystrobin in the nanobottles is then calculated using the azoxystrobin standard curve and the formula for calculating the encapsulation efficiency.

[0088]

[0089] The results are as follows Figure 3 As shown.

[0090] The results showed that the nanobottles exhibited excellent drug loading capacity.

[0091] 2) Example 1 ANT sustained-release experiment

[0092] An ANT containing 1g of AZOX was placed in a dialysis bag and sealed. It was then placed in 1L of a methanol:Tween-80:water (29.5:0.5:70; v / v / v) slow-release solution at different temperatures for a slow-release experiment. 3mL of solution was taken at regular intervals for measurement, and another 3mL of slow-release solution was added to maintain a constant solution volume. The relationship between the azoxystrobin release rate and time was obtained. The cumulative release rate of AZOX from the material was calculated using the following formula:

[0093]

[0094] In the formula, E r Cumulative ANT release (%); V e The volume (V) of the medium released at a certain time interval e =3mL); V0 is the volume of the released liquid (V0 = 1L); C n (mg mL -1 ) represents the concentration of AZOX in the sustained-release solution; m AZOX (mg) represents the total amount of AZOX in ANT.

[0095] The results are as follows Figure 7 As shown.

[0096] The results show that ANT has temperature-responsive release properties.

[0097] 3) Photothermal conversion experiment of phase change eutectic carrier with embedded photothermal agent in Example 1

[0098] Ten mL of suspensions of different concentrations of phase change eutectic support (TPS) without Cu-PDA nanobottles and phase change eutectic support (NTPS) with embedded nanobottles were placed in a glass dish, and a homogeneous suspension was obtained by sonication. An 808 nm laser (1 W / cm²) was then used. 2 Irradiate for 30 minutes, and measure the temperature of the suspension every 30 seconds using an infrared thermometer.

[0099] The results are as follows Figure 8As shown in the figure. TPS-1, TPS-2, TPS-10, and TPS-100 represent TPS concentrations of 1, 2, 10, and 100 mg / mL, respectively; NTPS-0.03, NTPS-0.06, NTPS-0.3, and NTPS-3 represent Cu-PDA nanobottles with concentrations of 0.03, 0.06, 0.3, and 3 mg / mL, respectively, added to the above TPS.

[0100] NT, TPS, and LA were placed together under sunlight to observe the phase transition of the materials.

[0101] The results are as follows Figure 9 As shown.

[0102] The results show that the Cu-PDA nanobottle, a photothermal agent, has excellent photothermal conversion performance, enabling phase transformation of the eutectic and achieving temperature-based drug release.

[0103] 4) Example 1: ANT's effect on the control of cotton Verticillium wilt

[0104] Cotton Verticillium wilt was selected as a soil-borne disease model to verify the control effect of ANT on soil-borne diseases.

[0105] Cotton seeds were cultured in a moist environment and sown after the seeds showed signs of sprouting. Inoculation began after the cotton plants had developed their second to third true leaves. The spore count of the spore suspension of Verticillium dahliae V991, the pathogen of cotton verticillium wilt, cultured in PD for one week, was adjusted to 1×10⁻⁶ spores. 7 40 mL of spore suspension was injected into the soil around the cotton roots. The roots were damaged with scissors before inoculation. Five treatments and one control were performed: ① CK (no inoculation, root damage treatment, and addition of sterile water); ② Root damage treatment, inoculated only with V991; ③ Root damage treatment, no inoculation, and 10 mL of ANT per plant; ④ Root damage treatment, inoculated with V991 first, and 10 mL of SC per plant 1 day later; ⑤ Root damage treatment, inoculated with V991 first, and 10 mL of WG per plant 1 day later; ⑥ Root damage treatment, inoculated with V991 first, and 10 mL of ANT per plant 1 day later. The AZOX concentration in SC, WG, and ANT was 0.15 mg / mL.

[0106] After cotton seedling inoculation, observe the occurrence of disease daily. Once the disease stabilizes, investigate the incidence rate and record the disease severity according to GB / T22101.5-2009 standard: Level 0: Healthy cotton plants, no diseased leaves, normal growth; Level 1: Less than one-quarter of the leaves of the cotton plant are affected, turning yellow and wilting; Level 2: More than one-quarter but less than one-half of the leaves of the cotton plant are affected, turning yellow and wilting; Level 3: More than one-half but less than three-quarters of the leaves of the cotton plant are affected, turning yellow and wilting; Level 4: More than three-quarters of the leaves of the cotton plant are affected, or all leaves fall off, and the cotton plant dies. Calculate the disease severity index and disease control efficacy using the following formula:

[0107]

[0108] The results are as follows Figure 10 As shown in Table 1.

[0109] Table 1

[0110]

[0111] The results showed that ANT had a good control effect on cotton Verticillium wilt and was superior to commonly available commercial formulations.

[0112] 5) Example 1: Experiment on the effect of ANT on cotton seed germination and seedling growth

[0113] Cotton seeds were soaked in deionized water for 6 hours and then sown in containers containing equal amounts of SC, WG, and ANT (0.02 mg AZOX / cm³). 3 ) and NT (0.06 mg / cm 3 0.2 mg / cm 3 Ten seeds were sown in each seedling pot containing peat moss, with three replicates for each treatment. The control group received deionized water. Cotton germination, seedling height, root length, stem length, dry weight, and fresh weight were recorded.

[0114] The results are as follows Figure 11 As shown in Table 2.

[0115] Table 2

[0116]

[0117]

[0118]

[0119] Note: Fresh weight / dry weight is the average weight of all cotton in each seedling pot.

[0120] The results showed that ANT and NT had no significant effect on cotton germination, root length, and plant height. In fact, cotton seedlings treated with ANT and low concentrations of NT were slightly heavier than those in the control group. ANT was not more toxic to plant growth than commercial formulations; it not only did not affect the normal growth of cotton, but could even promote plant growth to some extent.

[0121] 5) Example 1: Experiment on the effect of ANT on soil microbial community abundance

[0122] SC, WG, and ANT containing 100 mg AZOX were added to 100 g of dry soil, followed by 50 g of deionized water and mixed thoroughly. The control group was DIW. Each treatment was performed in triplicate, with soil relative humidity maintained at 50%–60%, and incubated at 298 K in the dark for 7 days. Then, 3 g of sample was taken from each group for DNA extraction.

[0123] The results are as follows Figure 12 As shown.

[0124] The results showed that ANT can improve the abundance and evenness of soil microbial communities, has a potential remediation effect on the negative impact of dominant soil bacteria, and reduces pesticide damage to microorganisms.

[0125] Example 2

[0126] The difference between this embodiment and Embodiment 1 is that carbon-based materials are used instead of polydopamine-metal ion complexes.

[0127] Example 3

[0128] The difference between this embodiment and Embodiment 1 is that microcapsules are used instead of nanobottles.

[0129] Example 4

[0130] The difference between this embodiment and Embodiment 1 is that tetrahydrofuran is used instead of toluene emulsion.

[0131] Example 5

[0132] The difference between this embodiment and Embodiment 1 is that decadecanoic acid is used instead of lauric acid.

[0133] Example 6

[0134] The difference between this embodiment and Embodiment 1 is that myristic acid is used instead of lauric acid.

[0135] Example 7

[0136] The difference between this embodiment and Embodiment 1 is that dimethyl sulfoxide is used instead of ethanol.

[0137] Example 8

[0138] The difference between this embodiment and Embodiment 1 is that hymexazol is used instead of pyraclostrobin.

[0139] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A phase change eutectic carrier with embedded photothermal agent, characterized in that: Materials with photothermal properties and phase change eutectic materials serve as phase change eutectic carriers with embedded photothermal agents, loading pesticide fungicides; The material with the photothermal properties is a photothermal agent, which is one of a carbon-based material, polydopamine, and a polydopamine-metal ion complex, wherein the metal ion in the polydopamine-metal ion complex is Cu. 2+ Ti 4+ Zn 2+ Mg 2+ Fe 3 + Fe 2+ Co 2+ Au 3+ Al 3+ With Ag + One of them; the photothermal agent has a mass fraction of 1% to 30% in the phase change eutectic carrier; The phase change eutectic material comprises fatty acids, organic solvents, and water; The fatty acid is one of lauric acid, caprylic acid, capric acid, myristic acid, nonanoic acid, palmitic acid, and stearic acid, and the mass fraction of the fatty acid in the phase change eutectic carrier is 10% to 60%. The organic solvent is a polar organic solvent miscible with water, and the mass fraction of the organic solvent in the phase change eutectic carrier is 20% to 40%, with the remainder being water.

2. The phase change eutectic carrier with embedded photothermal agent as described in claim 1, characterized in that: The morphology of the photothermal agent is one of the following: porous material, microcapsule, nanocrystal, nanotube, liposome, nanoparticle, and nanobottle.

3. The phase change eutectic carrier with embedded photothermal agent as described in claim 1, characterized in that: The organic solvent is one of ethanol, N-methylpyrrolidone, N,N-dimethylformamide, 2-pyrrolidone, and dimethyl sulfoxide.

4. A method for preparing a phase change eutectic carrier with an embedded photothermal agent as described in any one of claims 1-3, characterized in that, The process includes the following steps: mixing a photothermal agent with a fatty acid, dispersing the mixture in an organic solvent, and then forming a eutectic with water to obtain the phase change eutectic carrier with the embedded photothermal agent.

5. The method for preparing a phase change eutectic carrier with an embedded photothermal agent as described in claim 4, characterized in that, The photothermal agent is a polydopamine-metal ion complex nanobottle. The polydopamine-metal ion complex nanobottle is prepared by solution oxidation of dopamine and metal ions to obtain a polydopamine-metal ion complex shell, and then prepared by swelling-etching method to obtain a nanobottle with a single opening.

6. The method for preparing a phase change eutectic carrier with an embedded photothermal agent as described in claim 5, characterized in that, The preparation of the polydopamine-metal ion complex nanobottle is as follows: 1) Preparation of polydopamine-metal ion complex shell by solution oxidation method: Dopamine hydrochloride and metal ion compound are added to Tris buffer containing PS template microspheres, stirred to form polydopamine-metal ion complex, and the lower layer product is collected by centrifugation. 2) Swelling: Under room temperature shaking conditions, the polydopamine-metal ion complex obtained above was added to the PS mixed solution, and the lower layer product was collected by centrifugation. 3) Etching: Under room temperature oscillation conditions, the product collected in step 2) is added to a good solvent for PS template microspheres, and the lower layer product is collected by centrifugation to obtain polydopamine-metal ion complex nanobottles.

7. The method for preparing a phase change eutectic carrier with embedded photothermal agent as described in claim 6, characterized in that: In step 1), the mass ratio of dopamine hydrochloride to metal ion compound is 2-5:1; the content of PS template microspheres is 0.125% w / v; the stirring speed is 300-1200 rpm, and the stirring time is 8-24 h. In step 2), the PS mixed solution includes a good solvent and water, and the volume ratio of the good solvent to water is 1:2 to 9; the good solvent is one of toluene, benzene, xylene, dichloromethane, chloroform, carbon tetrachloride, tetrahydrofuran, acetone and ethyl acetate; the oscillation in step 2) is a vigorous oscillation with a rotation speed of 200 to 400 rpm.

8. The method for preparing a phase change eutectic carrier with an embedded photothermal agent as described in claim 6, characterized in that: In step 3), the good solvent is one of toluene, tetrahydrofuran, and xylene; the oscillation in step 3) is a vigorous oscillation with a rotation speed of 200-400 rpm.

9. The application of a phase change eutectic carrier with embedded photothermal agent as described in any one of claims 1-3 as a carrier for a fungicide in crops.

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