Phase change eutectic carrier embedded with photo-thermal agent as well as preparation method and application of phase change eutectic carrier

Abstract

The invention relates to the technical field of pesticides, and discloses a photo-thermal agent embedded phase change eutectic carrier and a preparation method and application thereof, and the photo-thermal agent embedded phase change eutectic carrier mainly comprises a photo-thermal agent, fatty acid, an organic solvent and water. The preparation process is simple, conditions are mild, a large number of auxiliaries are not needed, and quantitative preparation can be achieved; the dispersion and utilization rate of the bactericide can be improved through co-melting, and the effectiveness of the bactericide is improved; the bactericidal composition is suitable for various application modes such as seed coating and soil treatment, can exert various synergistic functions such as temperature response release, prolonging of drug retention time and enhancement of adhesiveness and permeability on the surfaces of pathogenic bacteria according to the use environment, is a green and efficient bactericide dosage form, and has a wide application prospect in green intelligent agriculture.

Description

Technical Field

[0001] The present invention relates to the technical field of pesticides, and in particular to a phase-change eutectic carrier with an embedded photothermal agent, and a preparation method and application thereof. Background Art

[0002] Soil-borne diseases refer to pathogens such as fungi, bacteria, nematodes and viruses that live in the soil with diseased remains and attack crops from the roots or stems when conditions are right. Among them, fungi are the main ones, such as Pythium spp., which causes crop seedling rot and damping-off, Rhizoctonia solani Kuhn, which causes seedling blight, Fusarium oxysporum and Verticillium alboatum, which cause plant wilt and death. Soil-borne diseases cause huge economic losses to agricultural production due to their rapid onset and few control methods. At present, chemical fungicides are still the main prevention and control strategy for soil-borne diseases. The mainstream fungicides include copper fungicides, organosulfur fungicides, triazole fungicides, methoxyacrylate fungicides, benzimidazole fungicides, etc. However, the above-mentioned fungicide raw materials are difficult to dissolve in water and need to be added with a variety of additives and organic solvents to be made into wettable powder (WP), suspension concentrate (SC), emulsifiable concentrate (EC) and other dosage forms through special processes. The environmental pollution and ecological toxicity caused by chemical synthetic additives (such as surfactants, thickeners, etc.) and solvents (such as toluene, xylene, etc.) cannot be ignored. Therefore, the development of green and efficient pesticide delivery systems (PDS) has become a research hotspot in the field of pesticide formulations.

[0003] Phase change material is a material that undergoes solid-liquid and liquid-solid phase changes under external temperature stimulation. Due to its temperature sensitivity, it has been widely studied in drug delivery. Eutectic is a common phenomenon in solid material systems. It refers to a mixture of different substances (usually two or more components) in a certain proportion, which melts at a certain temperature at the lowest melting point, and all components begin to melt at the same time at this temperature. Using phase change eutectic materials as pesticide carriers can achieve functionalities such as pesticide stabilization, temperature responsive release, and sustained and controlled release. Therefore, phase change eutectic carriers have great application prospects in the "reduction in quantity and increase in efficiency" of pesticides. Summary of the invention

[0004] The object of the present invention is to provide a phase-change eutectic carrier embedded with a photothermal agent and a preparation method and application thereof. The preparation method of the present invention is simple and mild. During the preparation process, 100% of the active drug remains in the carrier and can be evenly dispersed in the carrier, which is convenient for storage and transportation. The preparation has a simple formula, is green and safe, and has a temperature-responsive controlled release performance. The fungicide original drug and the carrier can synergistically resist bacteria. It is particularly suitable for use in seed coating, soil treatment, etc. to achieve the effect of reducing the amount of fungicide and increasing its efficiency.

[0005] The scheme of the present invention is:

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

[0007] The photothermal agent is one of black phosphorus, bifunctional phase change materials, metal nanomaterials, metal oxides, transition metal disulfides (TMDs), MXenes (two-dimensional transition metal carbides or nitrides), carbon-based materials, polydopamine, and polydopamine-metal ion complexes, and 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 a polydopamine-metal ion complex (Cu-PDA).

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

[0010] The photothermal agent has a morphology of one of porous materials, microcapsules, nanocrystals, nanotubes, liposomes, nanoparticles and nanobottles; the mass fraction of the photothermal agent in the phase-change eutectic carrier embedded with the photothermal agent is 1% to 30%.

[0011] As a preferred technical solution, nano bottle.

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

[0013] As a preferred technical solution, the diameter and the size of the bottle mouth of the nano bottle are nanometer-level, the diameter of the nano bottle is 600-700nm, and the size of the bottle mouth is 120-320nm.

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

[0015] As a preferred technical solution, the phase change eutectic material also includes an organic solvent and water, and 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 of the 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 an embedded photothermal agent, comprising mixing the 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 an embedded photothermal agent.

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

[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 are added to Tris buffer containing PS template beads, stirred to form polydopamine-metal ion complex, and the lower layer product is collected by centrifugation;

[0020] 2) Swelling: adding the polydopamine-metal ion complex obtained above to the PS mixed solution under room temperature shaking conditions, and collecting the lower layer product by centrifugation;

[0021] 3) Etching, adding the product collected in step 2) into a good solvent of PS template beads under room temperature oscillation, collecting the lower layer product by centrifugation, and obtaining a polydopamine-metal ion complex nanobottle.

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

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

[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, the stirring speed in 1) is 500-900 rpm and the stirring time is 12 hours.

[0026] As a preferred technical solution, the volume ratio of the 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 violent oscillation with a rotation speed of 200 to 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, wherein the Cu-PDA shell is prepared from dopamine and copper chloride by a solution oxidation method, and then a nanobottle with a single opening is prepared by a swelling-etching method.

[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 method: Dopamine hydrochloride and cupric chloride were added to a 10×10 -3 M, pH = 8.5 Tris-HCl buffer, stirred to form Cu-PDA@PS, and the lower layer product was collected by centrifugation.

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

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

[0035] The invention also provides an application of a nano bottle as a bactericide carrier.

[0036] The present invention also provides a fungicide carrier, which contains the Cu-PDA nanobottle.

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

[0038] The present invention also discloses the application of a phase-change eutectic carrier embedded with a photothermal agent as a carrier of a fungicide in crops, for example, for the prevention and treatment of soil-borne diseases. The application method can be selected from seed coating, soil treatment and other methods for application in agriculture.

[0039] As a preferred technical solution, the phase change eutectic carrier eutectic is a mixture of fatty acid, organic solvent 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 the embedded photothermal agent is 10%.

[0041] As a preferred technical solution, the fungicide is one or more of azoxystrobin, oxadiazine, fludioxonil, metalaxyl-M, thiophanate-methyl, mefenamic acid, and prochloraz.

[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%; the added amount of the photothermal agent is 3% of the total weight of the phase change eutectic material.

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

[0046] As a preferred technical solution, the AZOX loading amount 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 embedded with the photothermal agent is 10 to 100 mg / .

[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 embedded with the photothermal agent is 0.01 to 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 embedded with the photothermal agent is 0.01 to 1 g / g.

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

[0052] The present invention also provides a method for preparing a phase-change eutectic bactericidal agent embedded with a photothermal agent, comprising the following steps:

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

[0054] The bactericide and the photothermal agent have the above-mentioned selections. 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, fully shaken, and placed in a vacuum environment to obtain a drug-loaded nanobottle.

[0055] (2) Phase change eutectic carrier drug delivery

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

[0057] The present invention also discloses a phase-change eutectic carrier with an embedded photothermal agent, and a preparation method and application thereof. A material with photothermal properties and a phase-change eutectic material are the phase-change eutectic carrier with an embedded photothermal agent, and a pesticide bactericide is loaded; the material with photothermal properties is a photothermal agent, and the photothermal agent is one of black phosphorus, a bifunctional phase-change material, a metal nanomaterial, a metal oxide, a transition metal disulfide, a two-dimensional transition metal carbide, a two-dimensional transition metal carbide nitride, a carbon-based material, polydopamine and a polydopamine-metal ion complex, and 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 the present invention:

[0059] (1) The present invention uses different photothermal agents as temperature-responsive drug release switches, and loads fungicides by adsorption and eutectic loading, and loads fungicides into the photothermal agent and eutectic in one pot, thereby preparing a phase-change eutectic fungicide with embedded photothermal agent. Eutectic can increase the loading amount and dispersibility of fungicides, and achieve temperature-responsive release; Cu-PDA and fatty acids have broad-spectrum antibacterial properties, and can cooperate with chemical fungicides to fight soil-borne plant diseases, achieving the beneficial effect of "reducing the amount and increasing the efficiency" of pesticides.

[0060] (2) The phase-change eutectic fungicide with embedded photothermal agent provided by the present invention can regulate the eutectic state of fatty acid and fungicide by simply changing the mass fraction of fatty acid / organic solvent / water, and significantly improve the dispersibility and drug loading of fungicide in the carrier by eutectic. Based on the fact that the eutectic can be heated to above the phase change temperature (T m ), so the system is temperature responsive and can achieve cascade release of the bactericide through temperature changes, 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 fungicide embedded with a photothermal agent provided by the present invention is in a solid phase 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 to prevent the loss of active ingredients; when the temperature is high and sunny, a solid-liquid phase transition occurs to release the fungicide, which is transported downward to act on the roots of crops. At the same time, as the soil layer deepens, the temperature gradually decreases, and the carrier undergoes a liquid-solid transition, confining the fungicide to the soil layer at the root of the crop, prolonging the action time, improving the effect of the fungicide, 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 the present invention has simple preparation process, mild conditions, no need for a large amount of auxiliary agents, and can be prepared in a quantitative manner. The preparation process has low energy consumption, low amount of organic solvents, no loss of original medicine, and greatly reduces the loss rate of pesticides into the environment during use. The phase-change eutectic fungicide with embedded photothermal agent can improve the dispersibility and utilization rate of the original medicine, is suitable for various application methods such as seed coating and soil treatment, and can play a variety of synergistic functions according to the use environment. It is a type of green and efficient fungicide carrier. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 Schematic diagram of the preparation process of the Cu-PDA nanobottle of the photothermal agent and the phase change eutectic sterilizer embedded with the photothermal agent in Example 1 of the present invention.

[0064] Figure 2 These are scanning electron microscope images and transmission electron microscope images of the photothermal agent Cu-PDA nanobottle in Example 1 of the present invention.

[0065] Figure 3The loading rate and drug loading amount of the photothermal agent Cu-PDA nanobottle for azoxystrobin in Example 1 of the present invention.

[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 It is a different phase eutectic of lauric acid-ethanol-water in Example 1 of the present invention.

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

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

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

[0071] Fig. 9 The phase change of the phase-change eutectic carrier embedded with the photothermal agent under light in Example 1 of the present invention.

[0072] Fig.10 The control effect of the phase change eutectic fungicide embedded with a photothermal agent in Example 1 of the present invention on cotton Verticillium wilt.

[0073] Fig.11 The effect of the phase change eutectic fungicide embedded with a photothermal agent in Example 1 of the present invention on the germination and growth of cotton.

[0074] Fig.12 The effect of the phase change eutectic fungicide embedded with a photothermal agent in Example 1 of the present invention on the abundance of soil microbial populations. DETAILED DESCRIPTION

[0075] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below in conjunction with specific embodiments.

[0076] Unless otherwise specified, the raw materials and reagents used in the following examples are all chemically pure, commercially available, and no specific manufacturer is specified, or can be prepared by known methods.

[0077] Example 1

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

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

[0080] In the first step, 0.5 mL of polystyrene ball water suspension (2.5%, w / v) was taken, washed twice with water, and collected by centrifugation as a reaction template.

[0081] In the second step, the PS template collected above was dispersed in 10 mL of 1 mg mL -1 The dopamine hydrochloride was dissolved in a Tris-HCl buffer (10 mM, pH = 8.5), and 3 mg of copper chloride was added. The reaction was allowed to proceed at room temperature for 12 hours, and then the solid product after the reaction was collected by centrifugation at 6000 rpm for 5 minutes. 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 1% toluene emulsion containing 1% Tween-20, and then incubated on a shaker at 300 rpm at room temperature for 8 hours to swell the PS polystyrene beads. After the reaction, 20 mL of anhydrous ethanol was added to quench the swelling, and then the solid product was collected by centrifugation at 6000 rpm for 5 minutes and washed with ethanol three times; the obtained product was then incubated with 10 mL of THF on a shaker at 300 rpm at room temperature for 4 hours to dissolve all the PS. After the reaction, it was washed twice with THF and collected by centrifugation to obtain the Cu-PDA nanobottle.

[0083] In the fourth step, azoxystrobin was dissolved in ethyl acetate to form AZOX solutions of different concentrations, and then the Cu-PDA nanobottle was dispersed in the above solution, and after being fully shaken, it was placed in a vacuum environment for 6 hours to obtain the drug-loaded nanobottle.

[0084] In the fifth step, lauric acid was dissolved in ethanol (0.3 mg / mL), and then the drug-loaded nanobottles were dispersed in the lauric acid / ethanol solution, fully shaken, and then deionized water was added to encapsulate the drug-loaded nanobottles and make lauric acid, ethanol and water co-melt to solidify the free azoxystrobin, and obtain a phase change eutectic fungicide with an embedded photothermal agent loaded with azoxystrobin, hereinafter referred to as ANT. It was used for subsequent experimental verification.

[0085] 1) Example 1: Drug loading experiment of Cu-PDA nanobottle

[0086] The first step is to prepare a 0.1 mg / mL azoxystrobin / methanol solution in a 25 mL volumetric flask, and pipette 5 mL, 2.5 mL, 0.5 mL, 0.25 mL, 0.05 mL, and 0.025 mL into a 50 mL volumetric flask and dilute to volume with methanol. A standard curve of azoxystrobin was established by HPLC.

[0087] The second step is to measure the concentration of azoxystrobin encapsulated in the drug-loaded nanobottle obtained above by liquid chromatography, and then calculate the encapsulation rate of azoxystrobin in the nanobottle. The encapsulation rate of azoxystrobin in the nanobottle is calculated by combining the azoxystrobin standard curve and the encapsulation rate calculation formula.

[0088]

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

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

[0091] 2) Example 1 ANT sustained release experiment

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

[0093]

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

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

[0096] The results showed that ANT had temperature-responsive release properties.

[0097] 3) Experimental study on photothermal conversion of phase-change eutectic carrier with embedded photothermal agent in Example 1

[0098] 10 mL 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 uniform suspension was obtained by ultrasound. 2 ) for 30 min, and measure the temperature of the suspension every 30 s using an infrared thermometer.

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

[0100] Place NT, TPS and LA under sunlight together to observe the phase change of the materials.

[0101] The results are as follows Fig. 9 shown.

[0102] The results show that the photothermal agent Cu-PDA nanobottle has excellent photothermal conversion performance, which can cause the eutectic to undergo phase transition and realize the temperature release of the drug.

[0103] 4) Example 1 ANT control experiment on cotton 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 moisturized and cultured, and sown after the seeds turned white. Inoculation began after the cotton had grown the 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 7 / mL. The spore suspension was injected into the soil around the cotton roots, 40mL per plant. The roots were destroyed with scissors before inoculation of pathogens. There were 5 treatments and 1 control: ①CK, no inoculation, root injury treatment, and sterile water; ②root injury treatment, only inoculation of V991; ③root injury treatment, no inoculation, and 10mLANT per plant; ④root injury treatment, first inoculation of V991, and 10mLSC per plant after 1d. ⑤Root injury treatment, first inoculation of V991, and 10mLWG per plant after 1d. ⑥Root injury treatment, first inoculation of V991, and 10mLANT per plant after 1d. The AZOX concentration in SC, WG, and ANT was 0.15mg / mL.

[0106] After the cotton seedlings are inoculated, the occurrence of the disease is observed every day. After the disease is stable, the incidence rate is investigated and the disease level is recorded according to the GB / T22101.5-2009 standard: Level 0: The cotton plant is healthy, without diseased leaves, and grows normally; Level 1: Less than one-quarter of the leaves of the cotton plant are diseased, turning yellow and wilting; Level 2: More than one-quarter and less than one-half of the leaves of the cotton plant are diseased, turning yellow and wilting; Level 3: More than one-half and less than three-quarters of the leaves of the cotton plant are diseased, turning yellow and wilting; Level 4: More than three-quarters of the leaves of the cotton plant are diseased, or all the leaves fall off, and the cotton plant dies. The disease index and disease index control effect are calculated according to the following formula:

[0107]

[0108] The results are as follows Fig.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 the common commercial preparations on the market.

[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 h and then sown in a tube containing equal amounts of SC, WG, and ANT (0.02 mg AZOX / cm 3 ) and NT (0.06 mg / cm 3 , 0.2mg / cm 3 ) seedling pots with peat soil; 10 seeds were sown in each pot, and three replicates were set for each treatment; the control group was deionized water. The germination of cotton and the height, root length, stem length, dry weight and fresh weight of the seedlings were recorded.

[0114] The results are as follows Fig.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, the weight of cotton seedlings treated with ANT and low-concentration NT was slightly heavier than that of the CK group. ANT is not more toxic to plant growth than commercial preparations. Not only does it not affect the normal growth of cotton, but it can promote plant growth to a certain extent.

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

[0122] SC, WG, ANT containing 100 mg AZOX were added to dry soil (100 g), and then 50 g deionized water was added and mixed evenly. The control group was DIW. Three replicates were set for each treatment, and the relative humidity of the soil was maintained at 50%-60%, and cultured in the dark at 298K for 7 days. Then, 3 g samples were taken from each group for DNA extraction.

[0123] The results are as follows Fig.12 shown.

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

[0125] Example 2

[0126] The difference between this embodiment and embodiment 1 is that the polydopamine-metal ion complex is replaced by a carbon-based material.

[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 to replace the toluene emulsion.

[0131] Example 5

[0132] The difference between this embodiment and embodiment 1 is that lauric acid is replaced by dodecanoic 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 oxazolidinone is used instead of azoxystrobin.

[0139] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A phase-change eutectic carrier embedded with a photothermal agent, characterized in that: The material with photothermal properties and the phase change eutectic material are phase change eutectic carriers with embedded photothermal agents, and are loaded with pesticide bactericides; the material with photothermal properties is a photothermal agent, and the photothermal agent is one of black phosphorus, bifunctional phase change materials, metal nanomaterials, metal oxides, transition metal disulfides, two-dimensional transition metal carbides, two-dimensional transition metal carbide nitrides, carbon-based materials, polydopamine and polydopamine-metal ion complexes, and 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.

2. A phase-change eutectic carrier embedded with a photothermal agent as claimed in claim 1, characterized in that: The photothermal agent has a morphology of porous material, microcapsule, nanocrystal, nanotube, liposome, nanoparticle and nanobottle; the mass fraction of the photothermal agent in the phase-change eutectic carrier embedded with the photothermal agent is 1% to 30%.

3. The phase-change eutectic carrier embedded with a photothermal agent according to claim 1, characterized in that: The phase change eutectic material is a fatty acid, and the fatty acid is one of lauric acid, caprylic acid, capric acid, myristic acid, nonanoic acid, palmitic acid and stearic acid; the mass fraction of the fatty acid in the phase change eutectic carrier embedded with the photothermal agent is 10% to 60%.

4. The phase-change eutectic carrier embedded with a photothermal agent according to claim 1, characterized in that: The phase-change eutectic material also 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 of the embedded photothermal agent is 20% to 40%, and the remainder is water.

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

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

7. The method for preparing a phase-change eutectic carrier embedded with a photothermal agent according to claim 6, 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 beads, stirred to form polydopamine-metal ion complex, and the lower layer product is collected by centrifugation; 2) Swelling: adding the polydopamine-metal ion complex obtained above to the PS mixed solution under room temperature shaking conditions, and collecting the lower layer product by centrifugation; 3) Etching, adding the product collected in step 2) into a good solvent of PS template beads under room temperature oscillation, collecting the lower layer product by centrifugation, and obtaining a polydopamine-metal ion complex nanobottle.

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

9. The method for preparing a phase-change eutectic carrier embedded with a photothermal agent according to claim 7, characterized in that: The good solvent in step 3) is one of toluene, tetrahydrofuran and xylene; the oscillation in step 3) is a violent oscillation with a rotation speed of 200 to 400 rpm.

10. Use of the phase-change eutectic carrier with embedded photothermal agent as claimed in any one of claims 1 to 4 as a carrier of fungicide in crops.

Images