Environment-responsive intelligent release nano-pesticide, and preparation method and application thereof

Abstract

The present application belongs to the field of pesticide preparation, and particularly relates to an environment-responsive intelligent release nano-pesticide, a preparation method and application thereof. The environment-responsive intelligent release nano-pesticide provided by the present application comprises a first hydrophobic fiber layer, a hydrophilic fiber layer and a second hydrophobic fiber layer; the hydrophilic fiber layer is arranged between the first hydrophobic fiber layer and the second hydrophobic fiber layer; the hydrophilic fiber layer is loaded with a pesticide active ingredient and a hydrophilic component; and the first hydrophobic fiber layer and the second hydrophobic fiber layer are loaded with a hydrophobic component. The pesticide active ingredient is loaded into the inner layer of nanofibers, which significantly improves the dispersibility of the pesticide active ingredient, improves the biological activity of the pesticide active ingredient, and also can isolate the environment by using the outer layer of nanofibers to improve the thermal stability and oxidation resistance of the pesticide active ingredient. The hydrophobic outer layer can reduce the water permeability, increase the diffusion path of water, reduce the burst release of the pesticide active ingredient, realize the matching of the drug and the environment supply and demand, and improve the utilization rate of the pesticide.

Description

Technical Field

[0001] This invention belongs to the field of pesticide formulation, specifically relating to an environmentally responsive intelligent release nanopesticide, its preparation method, and its application. Background Technology

[0002] Pesticides are crucial agricultural inputs, playing a vital role in controlling pests, diseases, and weeds, promoting grain production, and ensuring food security. However, pesticide use also causes serious resource waste and environmental pollution. First, most pesticide production processes are complex, resulting in large quantities and types of toxic intermediates and byproducts; traditional pesticide formulations also have high organic solvent content. Second, pesticide production generates significant amounts of waste. Furthermore, current pesticide formulations are still primarily traditional, such as emulsifiable concentrates, wettable powders, and water-dispersible granules, with a low proportion of highly efficient and environmentally friendly formulations being produced and used. The short duration of action and low utilization rate of traditional pesticide formulations necessitate repeated applications to achieve optimal control, ultimately leading to large amounts of pesticides entering the environment, causing severe resource waste and environmental pollution, and seriously hindering sustainable agricultural development. Summary of the Invention

[0003] In view of this, the purpose of this invention is to provide an environmentally responsive intelligent release nanopesticide, its preparation method and application. The environmentally responsive intelligent release nanopesticide provided by this invention not only has good thermal stability, dispersibility and biological activity, but also can make specific responses to the external environment (temperature, pH), realize the supply and demand matching between the drug and the environment, reduce the amount of pesticide used, improve the pesticide utilization rate, and reduce agricultural non-point source pollution caused by pesticides.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] This invention provides an environmentally responsive smart release nanopesticide, comprising: a first hydrophobic fiber layer, a hydrophilic fiber layer, and a second hydrophobic fiber layer; the hydrophilic fiber layer is disposed between the first and second hydrophobic fiber layers; the hydrophilic fiber layer is loaded with pesticide active ingredients and hydrophilic components;

[0006] The first and second hydrophobic fiber layers are loaded with hydrophobic components; the hydrophobic components include one or more of ethyl cellulose, polylactic acid, chitosan, sodium alginate, polyvinylpyrrolidone and cellulose acetate;

[0007] The hydrophilic component includes one or more of gelatin, polycaprolactone, polyvinyl alcohol, polyethylene oxide, α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, methyl-β-cyclodextrin, 2-hydroxypropyl-β-cyclodextrin, 2-hydroxypropyl-γ-cyclodextrin, and 2-hydroxypropyl-α-cyclodextrin.

[0008] Preferably, the active pesticide ingredient includes one or more of the following: chlorothalonil, difenoconazole, hexaconazole, tebuconazole, azoxystrobin, cyazofamid, pyraclostrobin, prothioconazole, propiconazole, carbendazim, azoxystrobin, oxytetracycline, thiophanate-methyl, thiram, metalaxyl, oxadixyl, fluazinam, prochloraz, cyazofamid, thifluzamide, dimethomorph, fluopyram, quinoline copper, tricyclazole, iprodione, ethoxysulfuron, triadimefon, fluazinam, flusilazole, and fluazinam.

[0009] Preferably, the thickness of the first hydrophobic fiber layer is 0.1–100 μm; the thickness of the hydrophilic fiber layer is 0.1–100 μm; and the thickness of the second hydrophobic fiber layer is 0.1–100 μm.

[0010] Preferably, per m 2 The bioactive pesticides loaded with the environmentally responsive smart release nanopesticides range in mass from 0.1 to 500 mg.

[0011] Preferably, the specific surface area of ​​the first hydrophobic fiber layer is 100–2000 m². 2 ·g -1 The porosity is 40-95%; the specific surface area of ​​the second hydrophobic fiber layer is 100-2000 m². 2 ·g -1 The porosity is 40-95%.

[0012] This invention also provides a method for preparing the environmentally responsive smart-release nanopesticide described above, comprising the following steps:

[0013] The first hydrophobic layer electrospinning precursor solution is subjected to first electrospinning to obtain the first hydrophobic fiber layer.

[0014] The hydrophilic layer electrospinning precursor solution is electrospinned on the first hydrophobic fiber layer to obtain the hydrophilic fiber layer.

[0015] The second hydrophobic layer electrospinning precursor solution is electrospinned on the hydrophilic fiber layer to form the second hydrophobic fiber layer, resulting in an environmentally responsive intelligent release nano-pesticide.

[0016] The hydrophilic layer electrospinning precursor solution includes pesticide active ingredients, hydrophilic components, and a hydrophilic layer solvent;

[0017] The first hydrophobic layer electrospinning precursor solution and the second hydrophobic layer electrospinning precursor solution each independently include a hydrophobic component and a hydrophobic layer solvent.

[0018] Preferably, the mass ratio of the active pesticide ingredient to the hydrophilic ingredient is (1-10):50.

[0019] Preferably, the hydrophobic layer solvent includes deionized water, ethanol, and acetic acid; the volume ratio of the deionized water, ethanol, and acetic acid is 1:(2-3):(7-10); and the mass ratio of the hydrophobic component to the volume ratio of the hydrophobic layer solvent is (3-11) g:(10-20) mL.

[0020] Preferably, the conditions for the first, second, and third electrospinning are independent, including: a voltage of 10–20 kV, a receiving distance of 5–20 cm, a rotational speed of 10–200 rpm, an injection pump injection rate of 0.2–20 mL / h, and a relative humidity of 10%–80%.

[0021] The present invention also provides the application of the environmentally responsive intelligent release nanopesticides described in the above technical solutions or the environmentally responsive intelligent release nanopesticides prepared by the preparation methods described in the above technical solutions in agriculture.

[0022] This invention provides an environmentally responsive intelligent release nanopesticide, comprising: a first hydrophobic fiber layer, a hydrophilic fiber layer, and a second hydrophobic fiber layer; the hydrophilic fiber layer is disposed between the first and second hydrophobic fiber layers; the hydrophilic fiber layer is loaded with pesticide active ingredients and hydrophilic components; the first and second hydrophobic fiber layers are loaded with hydrophobic components; the hydrophobic components include one or more of ethyl cellulose, polylactic acid, chitosan, sodium alginate, polyvinylpyrrolidone, and cellulose acetate; the hydrophilic components include one or more of gelatin, polycaprolactone, polyvinyl alcohol, polyethylene oxide, α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, methyl-β-cyclodextrin, 2-hydroxypropyl-β-cyclodextrin, 2-hydroxypropyl-γ-cyclodextrin, and 2-hydroxypropyl-α-cyclodextrin.

[0023] This invention utilizes interactions such as physical adsorption, chemical bonding, ion exchange, and hydration to load pesticide active ingredients into inner nanofibers. This significantly improves the dispersibility of the pesticide active ingredients, increases the contact area between the active ingredients and harmful fungi in farmland, thereby enhancing the bioactivity of the active ingredients. Furthermore, the outer nanofibers isolate the environment, improving the thermal stability and antioxidant properties of the pesticide active ingredients. The inner nanofibers contain a hydrophilic component—a polyampholyte—which exhibits different properties and structures under different pH conditions. When the ambient pH is far from the isoelectric point, the hydrophilic component transforms into a linear structure, tending to dissolve in water and electrostatically repelling the drug, thus achieving pH-responsive drug release. Additionally, the invention utilizes the temperature range of the sol-gel transition to achieve temperature-responsive drug release. When the ambient temperature is below the transition temperature, the hydrophilic component gels, increasing the porosity of the nanofiber matrix and promoting drug release from the nanofibers. Secondly, the hydrophobic outer layer reduces water permeability, increases the diffusion path of water, and reduces the burst release of pesticide active ingredients. By preparing environmentally responsive intelligent release nanopesticides, not only can the concentration of pesticide active ingredients be maintained above the effective dose for a long time, but the supply and demand of pesticides and the environment can also be matched, minimizing the repeated application and waste of pesticides and improving pesticide utilization.

[0024] This invention also provides a method for preparing the aforementioned environmentally responsive intelligent release nanopesticides. This invention utilizes electrospinning technology to prepare nanopesticides loaded with pesticide active ingredients, significantly improving the dispersibility of the pesticide active ingredients and increasing the contact area between the pesticide active ingredients and harmful fungi in farmland, thereby enhancing the bioactivity of the pesticide active ingredients. The nanofiber matrix materials selected in this invention all possess good biocompatibility. Therefore, the prepared nanopesticides are green and environmentally friendly formulations. Attached Figure Description

[0025] Figure 1 The images show FE-SEM images of different materials, where a is gelatin nanofibers, b is gelatin nanofibers loaded with pyridoxine, c is ethyl cellulose nanofibers, and d is multilayer nanofibers prepared in Example 1 of this invention.

[0026] Figure 2 The thermogravimetric analysis diagrams are for different materials, where A is azoxystrobin technical, B is the multilayer nanofiber prepared in Example 1 of this invention, C is gelatin nanofiber loaded with azoxystrobin, D is gelatin nanofiber, and E is ethyl cellulose nanofiber.

[0027] Figure 3 Infrared spectra of different materials;

[0028] Figure 4X-ray diffraction patterns of different materials are shown, where A is azoxystrobin technical, B is gelatin nanofibers, C is gelatin nanofibers loaded with azoxystrobin, D is ethyl cellulose nanofibers, and E is multilayer nanofibers prepared in Example 1 of this invention.

[0029] Figure 5 The graph shows the inhibitory effects of different materials on Rhizoctonia solani, where A is the blank control group, B is the azoxystrobin technical group, and C is the multilayer nanofiber group prepared in Example 1 of this invention.

[0030] Figure 6 The in vitro release curve of the environmentally responsive smart release nanopesticide (multilayer nanofibers) prepared in Example 1 of the present invention is shown. Detailed Implementation

[0031] This invention provides an environmentally responsive smart release nanopesticide, comprising: a first hydrophobic fiber layer, a hydrophilic fiber layer, and a second hydrophobic fiber layer; the hydrophilic fiber layer is disposed between the first and second hydrophobic fiber layers; the hydrophilic fiber layer is loaded with pesticide active ingredients and hydrophilic components;

[0032] The first and second hydrophobic fiber layers are loaded with hydrophobic components; the hydrophobic components include one or more of ethyl cellulose, polylactic acid, chitosan, sodium alginate, polyvinylpyrrolidone and cellulose acetate;

[0033] The hydrophilic component includes one or more of gelatin, polycaprolactone, polyvinyl alcohol, polyethylene oxide, α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, methyl-β-cyclodextrin, 2-hydroxypropyl-β-cyclodextrin, 2-hydroxypropyl-γ-cyclodextrin, and 2-hydroxypropyl-α-cyclodextrin.

[0034] The environmentally responsive smart release nanopesticide provided by this invention comprises: a first hydrophobic fiber layer. In this invention, the first hydrophobic fiber layer is loaded with a hydrophobic component; the hydrophobic component includes one or more of ethyl cellulose, polylactic acid, chitosan, sodium alginate, polyvinylpyrrolidone, and cellulose acetate, preferably ethyl cellulose; the thickness of the first hydrophobic fiber layer is preferably 0.1–100 μm, more preferably 10–50 μm; the specific surface area of ​​the first hydrophobic fiber layer is 100–2000 m². 2 ·g -1 More preferably 1000-2000m 2 ·g -1 The porosity is 40–95%, more preferably 70–90%.

[0035] The environmentally responsive smart release nanopesticide provided by this invention comprises: a second hydrophobic fiber layer. In this invention, the second hydrophobic fiber layer is loaded with hydrophobic components; the hydrophobic components include one or more of ethyl cellulose, polylactic acid, chitosan, sodium alginate, polyvinylpyrrolidone, and cellulose acetate, preferably ethyl cellulose; the thickness of the second hydrophobic fiber layer is preferably 0.1–100 μm, more preferably 10–50 μm; the specific surface area of ​​the second hydrophobic fiber layer is 100–2000 m². 2 ·g -1 More preferably 1000-2000m 2 ·g -1 The porosity is 40–95%, more preferably 70–90%.

[0036] The environmentally responsive smart-release nanopesticide provided by this invention includes a hydrophilic fiber layer. In this invention, the hydrophilic fiber layer is placed between a first hydrophobic fiber layer and a second hydrophobic fiber layer; the hydrophilic fiber layer is loaded with pesticide active ingredients and hydrophilic components.

[0037] In this invention, the hydrophilic component includes one or more of gelatin, polycaprolactone, polyvinyl alcohol, polyethylene glycol, α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, methyl-β-cyclodextrin, 2-hydroxypropyl-β-cyclodextrin, 2-hydroxypropyl-γ-cyclodextrin, and 2-hydroxypropyl-α-cyclodextrin, preferably gelatin; the pesticide active ingredient preferably includes chlorothalonil, difenoconazole, hexaconazole, tebuconazole, azoxystrobin, cyazofamid, pyraclostrobin, prothioconazole, propiconazole, carbendazim, pyraclostrobin, azoxystrobin, and oxadiazon. The pesticide active ingredients are selected from one or more of the following: thiophanate-methyl, thiram, metalaxyl, hymexazol, fluazinam, prochloraz, cyazofamid, thifluzamide, dimethomorph, fluopyram, quinoline copper, tricyclazole, iprodione, ethionil, triadimefon, flutriafol, flusilazole, and fluazinam. More preferably, they are selected from one or more of difenoconazole, hexaconazole, tebuconazole, azoxystrobin, cyazofamid, pyraclostrobin, prothioconazole, thiophanate-methyl, thiram, prochloraz, and dimethomorph. Most preferably, they are difenoconazole, hexaconazole, tebuconazole, azoxystrobin, or cyazofamid. When the pesticide active ingredients are several of the above-mentioned ingredients, the present invention does not have a special limitation on the ratio of different types of pesticide active ingredients; any ratio is acceptable.

[0038] In this invention, the thickness of the hydrophilic fiber layer is preferably 0.1 to 100 μm, more preferably 10 to 50 μm.

[0039] In this invention, each m 2 The preferred mass of the pesticide active ingredient loaded in the environmentally responsive intelligent release nano-pesticide is 0.1–500 mg, more preferably 300–500 mg.

[0040] This invention utilizes interactions such as physical adsorption, chemical bonding, ion exchange, and hydration to load pesticide active ingredients into inner nanofibers, significantly improving the dispersibility of the active ingredients and increasing the contact area between the active ingredients and harmful fungi in farmland, thereby enhancing the bioactivity of the active ingredients. Furthermore, the outer nanofibers isolate the environment, improving the thermal stability and antioxidant properties of the active ingredients. This invention utilizes the hydrophilic component—a polyampholyte—in the inner nanofibers, which exhibits different properties and structures under different pH conditions. When the ambient pH value is far from the isoelectric point, the hydrophilic component transforms into a linear structure, tending to dissolve in water and generating electrostatic repulsion with the drug, thus achieving pH-responsive drug release. Additionally, by utilizing the temperature range of the sol-gel transition, temperature-responsive drug release is achieved. When the ambient temperature is below the transition temperature, the hydrophilic component gels, leading to an increase in the porosity of the nanofiber matrix and promoting drug release from the nanofibers. Secondly, the hydrophobic outer layer reduces water permeability, increases the diffusion path of water, and reduces the burst release of pesticide active ingredients. By preparing environmentally responsive intelligent release nanopesticides, not only can the concentration of pesticide active ingredients be maintained above the effective dose for a long time, but the supply and demand of pesticides and the environment can also be matched, minimizing the repeated application and waste of pesticides and improving pesticide utilization.

[0041] This invention also provides a method for preparing the environmentally responsive smart-release nanopesticide described above, comprising the following steps:

[0042] The first hydrophobic layer electrospinning precursor solution is subjected to first electrospinning to obtain the first hydrophobic fiber layer.

[0043] The hydrophilic layer electrospinning precursor solution is electrospinned on the first hydrophobic fiber layer to obtain the hydrophilic fiber layer.

[0044] The second hydrophobic layer electrospinning precursor solution is electrospinned on the hydrophilic fiber layer to form the second hydrophobic fiber layer, resulting in an environmentally responsive intelligent release nano-pesticide.

[0045] The hydrophilic layer electrospinning precursor solution includes pesticide active ingredients, hydrophilic components, and a hydrophilic layer solvent;

[0046] The first hydrophobic layer electrospinning precursor solution and the second hydrophobic layer electrospinning precursor solution each independently include a hydrophobic component and a hydrophobic layer solvent.

[0047] Unless otherwise specified, the present invention does not have special requirements on the source of the raw materials used in the preparation, and commercially available products well known to those skilled in the art can be used.

[0048] The present invention performs first electrospinning on the precursor liquid of the first hydrophobic layer to obtain the first hydrophobic fiber layer.

[0049] In this invention, the first hydrophobic layer electrospinning precursor solution includes a hydrophobic component and a hydrophobic layer solvent; the hydrophobic layer solvent preferably includes deionized water, ethanol and acetic acid; the volume ratio of the deionized water, ethanol and acetic acid is preferably 1:(2-3):(7-10), more preferably 1:(2-3):(7-8), and most preferably 1:2:7; the mass ratio of the hydrophobic component to the volume ratio of the hydrophobic layer solvent is preferably (3-11) g:(10-20) mL, more preferably (8-10) g:20 mL, and most preferably 9 g:20 mL.

[0050] In this invention, the preparation of the first hydrophobic layer electrospinning precursor solution is preferably carried out by mixing the hydrophobic component and the hydrophobic layer solvent and then homogenizing them. In this invention, the homogenization is preferably carried out under stirring conditions; the stirring is preferably carried out using a magnetic stirrer; the stirring speed is preferably 50–150 rpm, more preferably 50–100 rpm; the homogenization temperature is preferably room temperature; and the homogenization time is preferably 4–12 h, more preferably 6–8 h.

[0051] Before the first electrospinning, the present invention preferably further includes: ultrasonically venting the first hydrophobic layer electrospinning precursor solution; the ultrasonic temperature is preferably room temperature; the ultrasonic time is preferably 5-15 min, more preferably 10 min; the ultrasonic power is preferably 100-180 W, more preferably 150 W; and the ultrasonication is preferably water bath ultrasonication. The present invention removes gas from the electrospinning precursor solution through ultrasonication, thus avoiding the gas's influence on the fiber structure obtained by subsequent electrospinning.

[0052] In this invention, the conditions for the first electrospinning include: a voltage preferably of 10-20 kV, more preferably 14-17 kV; a collector receiving distance preferably of 5-20 cm, more preferably 10-17 cm; a collector rotation speed preferably of 10-200 rpm, more preferably 50-100 rpm; an injection pump injection speed preferably of 0.2-20 mL / h, more preferably 0.5-10 mL / h; and a relative humidity preferably of 10-80%, more preferably 15-30%. The first electrospinning time is preferably 0.5-3 h, more preferably 0.5-2 h.

[0053] After obtaining the first hydrophobic fiber layer, the present invention performs a second electrospinning on the first hydrophobic fiber layer using a hydrophilic layer electrospinning precursor solution to obtain a hydrophilic fiber layer.

[0054] In this invention, the hydrophilic layer electrospinning precursor solution preferably comprises a pesticide active ingredient, a hydrophilic component, and a hydrophilic layer solvent; the mass ratio of the pesticide active ingredient to the hydrophilic component is preferably (1-10):50, more preferably (2-5):50, and most preferably 1:25; the hydrophilic layer solvent preferably comprises ethyl acetate, acetic acid, and deionized water; the volume ratio of ethyl acetate, acetic acid, and deionized water is preferably 1:(3-5):(4-7), more preferably 1:(3-4):(4-6), and most preferably 1:4:5; the mass ratio of the hydrophilic component to the volume ratio of the hydrophilic layer solvent is preferably 1g:(4-6)mL, more preferably 1g:(4-5)mL, and most preferably 1g:5mL.

[0055] In this invention, the preparation of the hydrophilic layer electrospinning precursor solution is preferably carried out by mixing and homogenizing the pesticide active ingredient, the hydrophilic component, and the hydrophilic layer solvent. In this invention, the homogenization is preferably carried out under stirring conditions; the stirring is preferably carried out using a magnetic stirrer; the stirring speed is preferably 50–150 rpm, more preferably 50–100 rpm; the homogenization temperature is preferably room temperature; and the homogenization time is preferably 4–12 h, more preferably 6–8 h.

[0056] Before the second electrospinning, the present invention preferably further includes: ultrasonically venting the hydrophilic layer electrospinning precursor solution; the ultrasonic temperature is preferably room temperature; the ultrasonic time is preferably 5-15 min, more preferably 10 min; the ultrasonic power is preferably 100-180 W, more preferably 150 W; and the ultrasonication is preferably water bath ultrasonication. The present invention removes gas from the electrospinning precursor solution through ultrasonication, thus avoiding the gas's influence on the fiber structure obtained by subsequent electrospinning.

[0057] In this invention, the conditions for the second electrospinning include: a voltage preferably of 10-20 kV, more preferably 14-17 kV; a collector receiving distance preferably of 5-20 cm, more preferably 10-17 cm; a collector rotation speed preferably of 10-200 rpm, more preferably 50-100 rpm; an injection pump injection speed preferably of 0.2-20 mL / h, more preferably 0.5-10 mL / h; and a relative humidity preferably of 10-80%, more preferably 15-30%. The second electrospinning time is preferably 0.5-3 h, more preferably 0.5-2 h.

[0058] After obtaining the hydrophilic fiber layer, the present invention performs a third electrospinning on the hydrophilic fiber layer using the second hydrophobic layer electrospinning precursor solution to form a second hydrophobic fiber layer, thereby obtaining an environmentally responsive intelligent release nano-pesticide.

[0059] In this invention, the second hydrophobic layer electrospinning precursor solution includes a hydrophobic component and a hydrophobic layer solvent; the hydrophobic layer solvent preferably includes deionized water, ethanol and acetic acid; the volume ratio of the deionized water, ethanol and acetic acid is preferably 1:(2-3):(7-10), more preferably 1:(2-3):(7-8), and most preferably 1:2:7; the mass ratio of the hydrophobic component to the volume ratio of the hydrophobic layer solvent is preferably (3-11) g:(10-20) mL, more preferably (8-10) g:20 mL, and most preferably 9 g:20 mL.

[0060] In this invention, the preparation of the second hydrophobic layer electrospinning precursor solution is preferably carried out by mixing and homogenizing the hydrophobic component and the hydrophobic layer solvent. In this invention, the homogenization is preferably carried out under stirring conditions; the stirring is preferably carried out using a magnetic stirrer; the stirring speed is preferably 50–150 rpm, more preferably 50–100 rpm; the homogenization temperature is preferably room temperature; and the homogenization time is preferably 4–12 h, more preferably 6–8 h.

[0061] Before the second electrospinning, the present invention preferably further includes: ultrasonically venting the electrospinning precursor solution of the second hydrophobic layer; the ultrasonic temperature is preferably room temperature; the ultrasonic time is preferably 5-15 min, more preferably 10 min; the ultrasonic power is preferably 100-180 W, more preferably 150 W; and the ultrasonication is preferably water bath ultrasonication. The present invention removes gas from the electrospinning precursor solution through ultrasonication, thus avoiding the gas's influence on the fiber structure obtained by subsequent electrospinning.

[0062] In this invention, the conditions for the third electrospinning include: a voltage preferably of 10-20 kV, more preferably 14-17 kV; a collector receiving distance preferably of 5-20 cm, more preferably 10-17 cm; a collector rotation speed preferably of 10-200 rpm, more preferably 50-100 rpm; an injection pump injection speed preferably of 0.2-20 mL / h, more preferably 0.5-10 mL / h; and a relative humidity preferably of 10-80%, more preferably 15-30%. The time for the third electrospinning is preferably 0.5-3 h, more preferably 0.5-2 h.

[0063] In this invention, the equipment used for the first, second, and third electrospinning is preferably an electrospinning machine; the electrospinning machine preferably consists of a high-voltage power supply, an injection pump, a syringe, and a collector; the electrospinning process preferably involves sequentially placing the first hydrophobic layer electrospinning precursor solution, the hydrophilic layer electrospinning precursor solution, and the second hydrophobic layer electrospinning precursor solution after degassing into syringes, fixing the syringes in the injection pump, and adjusting the voltage, the injection pump injection speed, the receiving distance of the collector, and the rotation speed to perform electrospinning and obtain an environmentally responsive intelligent release nano-pesticide.

[0064] This invention utilizes electrospinning technology to prepare nanopesticides loaded with pesticide active ingredients, significantly improving the dispersibility of the pesticide active ingredients and increasing the contact area between the pesticide active ingredients and harmful fungi in farmland, thereby enhancing the bioactivity of the pesticide active ingredients. The nanofiber matrix materials selected in this invention all possess excellent biocompatibility. Therefore, the prepared nanopesticides are green and environmentally friendly formulations.

[0065] The present invention also provides the application of the environmentally responsive intelligent release nanopesticides described in the above technical solutions or the environmentally responsive intelligent release nanopesticides prepared by the preparation methods described in the above technical solutions in agriculture.

[0066] In this invention, the preferred application methods are: seed dressing, seed soaking, soaking, seed suffocation, soil treatment, mulching, seed coating, or drip irrigation, with seed dressing or soaking being more preferred; the preferred application rate of the environmentally responsive intelligent release nano-pesticide is 50-500 mg / mu, with 80-320 mg / mu being more preferred.

[0067] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, but they should not be construed as limiting the scope of protection of the present invention.

[0068] Example 1

[0069] Accurately weigh 1.0000g of gelatin and 0.0415g of azoxystrobin, add 0.5mL of ethyl acetate, 2mL of acetic acid and 2.5mL of deionized water, and stir the mixture at 100rpm for 8 hours at room temperature to ensure thorough mixing and dissolution, thus obtaining the hydrophilic electrospinning precursor solution.

[0070] Accurately weigh 4.5000g of ethyl cellulose, add 7mL of acetic acid, 2mL of ethanol and 1mL of deionized water, and stir the above mixture at 100rpm for 8h at room temperature to fully mix and dissolve it, to obtain the first hydrophobic layer electrospinning precursor solution (second hydrophobic layer electrospinning precursor solution).

[0071] The first hydrophobic layer electrospinning precursor liquid (second hydrophobic layer electrospinning precursor liquid) and the hydrophilic layer electrospinning precursor liquid were placed in an ultrasonic cleaner and ultrasonically cleaned for 10 minutes at 150W power in a room temperature environment to remove gas.

[0072] The electrospinning precursor solution of the first hydrophobic layer after degassing was drawn into a 1mL disposable sterile syringe. The syringe was fixed in the injection pump. The voltage of the electrospinning machine was adjusted to 15kV, the injection pump injection speed was 0.5mL / h, and the collector receiving distance was 15cm. After electrospinning for 0.5h, the first hydrophobic fiber layer was obtained.

[0073] The hydrophilic layer electrospinning precursor solution after degassing was drawn into a 1mL disposable sterile syringe. The syringe was fixed in the injection pump. The voltage of the electrospinning machine was adjusted to 15kV, the injection pump injection speed was 0.5mL / h, and the collector receiving distance was 15cm. After electrospinning on the first hydrophobic fiber layer for 0.5h, the hydrophilic fiber layer was obtained.

[0074] The pre-spinning solution of the second hydrophobic layer after degassing was drawn into a 1 mL disposable sterile syringe. The syringe was fixed in the injection pump. The voltage of the electrospinning machine was adjusted to 15 kV, the injection pump injection speed was 0.5 mL / h, and the collector receiving distance was 15 cm. After electrospinning on the hydrophilic fiber layer for 0.5 h, an environmentally responsive intelligent release nano-pesticide was obtained.

[0075] Example 2

[0076] The difference from Example 1 is that 0.0415g of cyazofamid was used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0077] Example 3

[0078] The difference from Example 1 is that 0.0415g of chlorothalonil was used instead of azoxystrobin in Example 1, while all other contents are the same as in Example 1.

[0079] Example 4

[0080] The difference from Example 1 is that 0.0415g of difenoconazole is used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0081] Example 5

[0082] The difference from Example 1 is that 0.0415g of hexaconazole is used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0083] Example 6

[0084] The difference from Example 1 is that 0.0415g of tebuconazole is used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0085] Example 7

[0086] The difference from Example 1 is that 0.0415g of pyraclostrobin was used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0087] Example 8

[0088] The difference from Example 1 is that 0.0415g of prothioconazole is used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0089] Example 9

[0090] The difference from Example 1 is that 0.0415g of propiconazole is used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0091] Example 10

[0092] The difference from Example 1 is that 0.0415g of carbendazim was used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0093] Example 11

[0094] The difference from Example 1 is that 0.0415g of azoxystrobin was used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0095] Example 12

[0096] The difference from Example 1 is that 0.0415g of azoxystrobin was used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0097] Example 13

[0098] The difference from Example 1 is that 0.0415g of azoxystrobin was used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0099] Example 14

[0100] The difference from Example 1 is that 0.0415g of thiophanate-methyl is used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0101] Example 15

[0102] The difference from Example 1 is that 0.0415g of thiram is used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0103] Example 16

[0104] The difference from Example 1 is that 0.0415g of metalaxyl was used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0105] Example 17

[0106] The difference from Example 1 is that 0.0415g of hymexazol is used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0107] Example 18

[0108] The difference from Example 1 is that 0.0415g of fluazinam is used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0109] Example 19

[0110] The difference from Example 1 is that 0.0415g of imazalil was used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0111] Example 20

[0112] The difference from Example 1 is that 0.0415g of cyazofamid was used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0113] Example 21

[0114] The difference from Example 1 is that 0.0415g of thifluzamide is used instead of azoxystrobin in Example 1, while the rest are the same as in Example 1.

[0115] Example 22

[0116] The difference from Example 1 is that 0.0415g of dimethomorph was used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0117] Example 23

[0118] The difference from Example 1 is that 0.0415g of fluopyram is used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0119] Example 24

[0120] The difference from Example 1 is that 0.0415g of quinoline copper is used instead of azoxystrobin in Example 1, while the rest are the same as in Example 1.

[0121] Example 25

[0122] The difference from Example 1 is that 0.0415g of tricyclazole is used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0123] Example 26

[0124] The difference from Example 1 is that 0.0415g of iprodione was used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0125] Example 27

[0126] The difference from Example 1 is that 0.0415g of ethoxysulfuron is used instead of azoxystrobin in Example 1, while the rest are the same as in Example 1.

[0127] Example 28

[0128] The difference from Example 1 is that 0.0415g of triadimefon is used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0129] Example 29

[0130] The difference from Example 1 is that 0.0415g of flutriafol is used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0131] Example 30

[0132] The difference from Example 1 is that 0.0415g of flusilazole is used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0133] Example 31

[0134] The difference from Example 1 is that 0.0415g of fluazinam is used instead of azoxystrobin in Example 1, and all other contents are the same as in Example 1.

[0135] Example 32

[0136] The difference from Example 1 is that the mixture was stirred at 100 rpm for 6 hours at room temperature to ensure thorough mixing and dissolution, resulting in a hydrophilic electrospinning precursor solution. All other contents are the same as in Example 1.

[0137] Example 33

[0138] The difference from Example 1 is that the mixture was stirred at 100 rpm for 10 hours at room temperature to ensure thorough mixing and dissolution, resulting in a hydrophilic electrospinning precursor solution. All other contents are the same as in Example 1.

[0139] Example 34

[0140] The difference from Example 1 is that the mixture was stirred at 100 rpm for 12 hours at room temperature to ensure thorough mixing and dissolution, resulting in a hydrophilic electrospinning precursor solution. All other contents are the same as in Example 1.

[0141] Example 35

[0142] The difference from Example 1 is that 1.2500g of gelatin is used instead of the gelatin in Example 1, and all other contents are the same as in Example 1.

[0143] Example 36

[0144] The difference from Example 1 is that 0.7500g of gelatin is used instead of the gelatin in Example 1, and all other contents are the same as in Example 1.

[0145] Example 37

[0146] The difference from Example 1 is that 5.0000g of ethyl cellulose is used instead of the ethyl cellulose in Example 1, and all other contents are the same as in Example 1.

[0147] Example 38

[0148] The difference from Example 1 is that 4.0000g of ethyl cellulose is used instead of the ethyl cellulose in Example 1, and all other contents are the same as in Example 1.

[0149] Example 39

[0150] The difference from Example 1 is that 3.5000g of ethyl cellulose is used instead of the ethyl cellulose in Example 1, and all other contents are the same as in Example 1.

[0151] Example 40

[0152] The difference from Example 1 is that the voltage of the electrospinning machine is adjusted to 16kV, while the rest is the same as Example 1.

[0153] Example 41

[0154] The difference from Example 1 is that the voltage of the electrospinning machine is adjusted to 17kV, while the rest is the same as Example 1.

[0155] Example 42

[0156] The difference from Example 1 is that the voltage of the electrospinning machine is adjusted to 14kV, while the rest is the same as Example 1.

[0157] Example 43

[0158] The difference from Example 1 is that electrospinning was performed for 1 hour, but all other contents are the same as in Example 1.

[0159] Example 44

[0160] The difference from Example 1 is that electrospinning was performed for 1.5 hours, but all other contents are the same as in Example 1.

[0161] Example 45

[0162] The difference from Example 1 is that electrospinning was performed for 2 hours, but all other contents are the same as in Example 1.

[0163] Example 46

[0164] The difference from Example 1 is that electrospinning was performed for 3 hours, but all other contents are the same as in Example 1.

[0165] Comparative Example 1

[0166] Accurately weigh 1.0000g of gelatin, add 0.5mL of ethyl acetate, 2mL of acetic acid and 2.5mL of deionized water, and stir the mixture at 100rpm for 8 hours at room temperature to ensure thorough mixing and dissolution, thus obtaining the gelatin electrospinning precursor solution.

[0167] The gelatin electrospinning precursor solution was placed in an ultrasonic cleaner and ultrasonicated at 150W for 10 minutes at room temperature to remove gas.

[0168] After degassing, the gelatin electrospinning precursor solution was drawn into a 1mL disposable sterile syringe. The syringe was fixed in the injection pump. The voltage of the electrospinning machine was adjusted to 15kV, the injection pump speed was 0.5mL / h, and the collector receiving distance was 15cm. After electrospinning for 0.5h, a gelatin nanofiber layer was obtained.

[0169] Comparative Example 2

[0170] Accurately weigh 1.0000g of gelatin and 0.0415g of azoxystrobin, add 0.5mL of ethyl acetate, 2mL of acetic acid and 2.5mL of deionized water, and stir the mixture at 100rpm for 8 hours at room temperature to ensure thorough mixing and dissolution, thus obtaining the hydrophilic electrospinning precursor solution.

[0171] The hydrophilic layer electrospinning precursor solution was placed in an ultrasonic cleaner and ultrasonicated at 150W for 10 minutes at room temperature to remove gas.

[0172] The hydrophilic layer electrospinning precursor solution after degassing was drawn into a 1 mL disposable sterile syringe. The syringe was fixed in the injection pump. The electrospinning machine voltage was adjusted to 15 kV, the injection pump injection speed was 0.5 mL / h, and the collector receiving distance was 15 cm. After electrospinning for 0.5 h, a gelatin nanofiber layer loaded with azoxystrobin was obtained.

[0173] Comparative Example 3

[0174] Accurately weigh 4.5000g of ethyl cellulose, add 7mL of acetic acid, 2mL of ethanol and 1mL of deionized water, and stir the mixture at 100rpm for 8h at room temperature to fully mix and dissolve it, thus obtaining the ethyl cellulose electrospinning precursor solution.

[0175] The ethyl cellulose electrospinning precursor solution was placed in an ultrasonic cleaner and ultrasonicated at 150W for 10 minutes at room temperature to remove gas.

[0176] The ethyl cellulose electrospinning precursor solution after degassing was drawn into a 1 mL disposable sterile syringe. The syringe was fixed in the injection pump. The voltage of the electrospinning machine was adjusted to 15 kV, the injection pump speed was 0.5 mL / h, and the collector receiving distance was 15 cm. After electrospinning for 0.5 h, an ethyl cellulose nanofiber layer was obtained.

[0177] Performance testing

[0178] (1) Fiber diameter determination: Appropriate amounts of gelatin nanofibers prepared in Comparative Example 1, gelatin nanofibers loaded with azoxystrobin prepared in Comparative Example 2, ethyl cellulose nanofibers prepared in Comparative Example 3, and environmentally responsive smart-release nanopesticides (multilayer nanofibers) prepared in Example 1 were taken and their morphology was studied using a field emission scanning electron microscope SU8010 (Hitachi, Japan). The FE-SEM images are shown below. Figure 1 As shown, a is gelatin nanofiber, b is gelatin nanofiber loaded with pyridoxine, c is ethyl cellulose nanofiber, and d is the multilayer nanofiber prepared in Example 1 of this invention.

[0179] Depend on Figure 1 As shown, the gelatin nanofibers, gelatin nanofibers loaded with azoxystrobin, ethyl cellulose nanofibers, and the multilayer nanofibers prepared in Example 1 are all bead-free and have smooth surfaces. The average fiber diameter was determined using Nano Measure software by randomly measuring 100 fibers in each image; the average diameter of the multilayer nanofibers prepared in Example 1 was measured to be 471 ± 113 nm.

[0180] (2) Thermal stability determination: 5 mg each of azoxystrobin technical grade, gelatin nanofibers prepared in Comparative Example 1, azoxystrobin-loaded gelatin nanofibers prepared in Comparative Example 2, ethyl cellulose nanofibers prepared in Comparative Example 3, and environmentally responsive smart-release nanopesticide (multilayer nanofibers) prepared in Example 1 were placed in 2 mL alumina crucibles and heated from 25 °C to 800 °C at a heating rate of 10 °C / min, with continuous flow of dry N2 (50 mL / min) throughout. Weight loss curves were plotted with temperature on the x-axis and mass percentage on the y-axis. The results are shown below. Figure 2As shown, A is azoxystrobin technical grade, B is the multilayer nanofiber prepared in Example 1 of this invention, C is gelatin nanofiber loaded with azoxystrobin, D is gelatin nanofiber, and E is ethyl cellulose nanofiber.

[0181] Depend on Figure 2 It can be seen that the main mass loss of azoxystrobin technical grade pesticide begins at 173℃ and ends at 314℃, with the maximum weight loss rate at 293℃. The main mass loss of the environmentally responsive smart-release nanopesticide (multilayer nanofibers) prepared in Example 1 of this invention begins at 261℃ and ends at 448℃, with the maximum weight loss rate at 410℃. This indicates that the thermal stability of the pesticide's active ingredient can be improved by preparing multilayer nanofibers.

[0182] (3) FTIR analysis: 1 mg each of azoxystrobin technical grade, gelatin nanofibers prepared in Comparative Example 1, azoxystrobin-loaded gelatin nanofibers prepared in Comparative Example 2, ethyl cellulose nanofibers prepared in Comparative Example 3, and the environmentally responsive smart-release nanopesticide (multilayer nanofibers) prepared in Example 1 were mixed with 100 mg of potassium bromide and ground to form powders for Fourier transform infrared spectroscopy analysis. This analysis was performed using an ALPHA-T infrared spectrometer (Bruker VERTEX 70), with the wavenumber range set to 4000–400 cm⁻¹. -1 The resolution is 2cm. -1 The infrared spectrum was obtained after 32 scans. Figure 3 As shown.

[0183] Depend on Figure 3 It can be seen that the technical grade of azoxystrobin is at 1714 cm. -1 (C=O stretching vibration), 1628cm -1 (C=N stretching vibration) possesses a characteristic absorption peak; gelatin nanofibers exhibit an absorption peak at 3378 cm⁻¹. -1 (-OH stretching vibration) and 1655cm -1 (C=O stretching vibration) has an absorption peak; ethyl cellulose nanofibers show an absorption peak at 3480 cm⁻¹. -1 (-OH stretching vibration) and 1114 cm -1 The C=O stretching vibration exhibits an absorption peak; compared to the technical grade azoxystrobin, the C=O stretching vibration peak in the multilayer nanofibers prepared in Example 1 of this invention is reduced from 1714 cm⁻¹. -1 Offset to 1641cm -1 The -OH stretching vibration peak is from 3378 cm⁻¹ -1 Offset to 3484cm -1 This indicates that hydrogen bonds have formed between adjacent fiber layers.

[0184] (4) X-ray diffraction analysis: using Cu k-α radiation A Phillips X-ray diffractometer was used to perform diffraction analysis on azoxystrobin technical, gelatin nanofibers prepared in Comparative Example 1, gelatin nanofibers loaded with azoxystrobin prepared in Comparative Example 2, ethyl cellulose nanofibers prepared in Comparative Example 3, and the environmentally responsive smart-release nanopesticide (multilayer nanofibers) prepared in Example 1 of this invention. The conditions were: tube voltage of 40 kV and tube flow rate of 30 mA; X-ray diffractometer scanning rate of 2° / min within the range of 5–45° to measure the diffraction patterns of the samples. The X-ray diffraction patterns are shown below. Figure 4 As shown, A is azoxystrobin technical, B is gelatin nanofiber, C is gelatin nanofiber loaded with azoxystrobin, D is ethyl cellulose nanofiber, and E is the multilayer nanofiber prepared in Example 1 of this invention.

[0185] Depend on Figure 4 It can be seen that the technical grade of azoxystrobin has characteristic diffraction peaks at 16.3°, 22.0°, 22.9°, 25.3° and 25.6°; gelatin nanofibers, gelatin nanofibers loaded with azoxystrobin, ethyl cellulose nanofibers and the multilayer nanofibers prepared in Example 1 of this invention all show broad and coarse arc peaks, which indicates that they are all amorphous structures. This is because azoxystrobin is loaded into gelatin nanofibers, and the gelatin hinders the crystallization of azoxystrobin.

[0186] (5) Antifungal activity test: A comparative study was conducted on naturally growing fungi and fungi treated with azoxystrobin technical and the environmentally responsive intelligent release nanopesticide (multilayer nanofibers) prepared in Example 1 of this invention to evaluate antifungal activity. The entire experiment was conducted in a sterile operating table. When the temperature of potato dextrose agar medium dropped to about 55°C, 10 mL of medium was slowly poured into a petri dish. The medium was allowed to cool and solidify. Filter paper soaked in azoxystrobin solution and the multilayer nanofibers prepared in Example 1 of this invention were placed in the center of the medium. A 6 mm diameter hyphae was placed in the center of the filter paper and the multilayer nanofibers. Finally, the medium was inverted and cultured at 25°C. The growth diameter of the hyphae was recorded after 3, 4, 5, and 12 days. The results are as follows: Figure 5 As shown, A is the blank control group, B is the technical grade of azoxystrobin, and C is the multilayer nanofiber prepared in Example 1 of this invention.

[0187] Depend on Figure 5 It can be seen that, compared with naturally growing Rhizoctonia solani, Rhizoctonia solani treated with azoxystrobin technical grade grows more slowly, indicating that azoxystrobin has antifungal activity; Rhizoctonia solani in the multilayer nanofiber group prepared in Example 1 of this invention grows the slowest, and the fungus cannot grow on the multilayer nanofiber after 12 days, indicating that the preparation of multilayer nanofiber can improve the antifungal activity of azoxystrobin technical grade, which is achieved by improving the dispersibility of azoxystrobin technical grade.

[0188] (6) In vitro release of multilayer nanofibers: Accurately weigh 0.0300g of the environmentally responsive intelligent release nanopesticide (multilayer nanofibers) prepared in Example 1 of this invention and dissolve it in 5mL of phosphate buffer solution. The above solution was placed in a dialysis bag, both ends of which were tied tightly. The bag was then placed in 80 mL of release medium at different temperatures (20℃, 25℃, 30℃) and different pH values ​​(5.0, 7.4, 8.8) at a shaking speed of 100 rpm. At 1.0 h, 2.0 h, 4.0 h, 6.0 h, 8.0 h, 12.0 h, 24.0 h, 30.0 h, 36.0 h, 48.0 h, 54.0 h, 60.0 h, 72.0 h, 78.0 h, 84.0 h, and 96.0 h, 5 mL of release medium was collected from outside the dialysis bag, and an equal amount of fresh release medium at the same temperature was added. The absorbance of azoxystrobin in the release medium at each time point was measured using a UV-Vis spectrophotometer. The azoxystrobin content was determined using the azoxystrobin standard curve. An in vitro release curve of the multilayer nanofibers was plotted with time on the x-axis and cumulative release rate on the y-axis. The results are shown below. Figure 6 As shown.

[0189] Depend on Figure 6 It was found that multilayer nanofibers exhibited significant sustained-release characteristics at different temperatures within an environment with pH 7.4. This is because the outer ethyl cellulose nanofibers can reduce water permeability, increase the diffusion pathway of water, and reduce drug burst release. At pH 7.4 and 20℃, the cumulative release rate of the multilayer nanofibers reached 48.70% after 24 hours and 76.04% after 96 hours. However, at pH 7.4 and 25℃, the cumulative release rate of the multilayer nanofibers was lower than that of the pH 7.4 and 20℃ group in the first 51 hours, but reached 91.08% after 96 hours, almost comparable to the pH 7.4 and 30℃ group. This demonstrates that the multilayer nanofibers exhibit temperature-responsive release characteristics. The release behavior of the multilayer nanofibers at pH 5.0, 7.4, and 8.8 was investigated at an ambient temperature of 25℃. Figure 6 It can be seen that the cumulative release rate of multilayer nanofibers reached 93.79% and 86.40% after 96 hours in environments with pH 7.4 and 8.8, respectively, while the cumulative release rate was 43.27% at pH 5.0. This indicates that the release rate of multilayer nanofibers is higher in weakly alkaline environments, showing that multilayer nanofibers have the characteristic of releasing in response to acidity and alkalinity.

[0190] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention and not all embodiments. People can obtain other embodiments based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. An environmentally responsive smart release nanopesticide, characterized in that, include: A first hydrophobic fiber layer, a hydrophilic fiber layer, and a second hydrophobic fiber layer; the hydrophilic fiber layer is located between the first and second hydrophobic fiber layers; the hydrophilic fiber layer is loaded with pesticide active ingredients and hydrophilic components; The first and second hydrophobic fiber layers are loaded with a hydrophobic component; the hydrophobic component is ethyl cellulose. The hydrophilic component is gelatin; The active ingredients of the pesticide include one or more of the following: chlorothalonil, difenoconazole, hexaconazole, tebuconazole, azoxystrobin, cyazofamid, pyraclostrobin, prothioconazole, propiconazole, carbendazim, azoxystrobin, oxytetracycline, thiophanate-methyl, thiram, metalaxyl, oxadixyl, fluazinam, prochloraz, cyazofamid, thifluzamide, dimethomorph, fluopyram, quinoline copper, tricyclazole, iprodione, ethoxysulfuron, triadimefon, fluazinam, flusilazole, and fluazinam. per m 2 The environmentally responsive intelligent release nano-pesticides contain pesticide active ingredients with a mass of 0.1~500mg. The specific surface area of ​​the first hydrophobic fiber layer is 100~2000 m². 2 ·g -1 The porosity is 40-95%; the specific surface area of ​​the second hydrophobic fiber layer is 100-2000 m². 2 ·g -1 The porosity is 40-95%.

2. The environmentally responsive intelligent release nanopesticide according to claim 1, characterized in that, The thickness of the first hydrophobic fiber layer is 0.1~100μm; the thickness of the hydrophilic fiber layer is 0.1~100μm; and the thickness of the second hydrophobic fiber layer is 0.1~100μm.

3. The method for preparing the environmentally responsive smart release nanopesticide according to any one of claims 1 to 2, characterized in that, Includes the following steps: The first hydrophobic layer electrospinning precursor solution is subjected to first electrospinning to obtain the first hydrophobic fiber layer. The hydrophilic layer electrospinning precursor solution is electrospinned on the first hydrophobic fiber layer to obtain the hydrophilic fiber layer. The second hydrophobic layer electrospinning precursor solution is electrospinned on the hydrophilic fiber layer to form the second hydrophobic fiber layer, resulting in an environmentally responsive intelligent release nano-pesticide. The hydrophilic layer electrospinning precursor solution includes pesticide active ingredients, hydrophilic components, and a hydrophilic layer solvent; The first hydrophobic layer electrospinning precursor solution and the second hydrophobic layer electrospinning precursor solution each independently include a hydrophobic component and a hydrophobic layer solvent.

4. The preparation method according to claim 3, characterized in that, The mass ratio of the active pesticide ingredient to the hydrophilic ingredient is (1~10):

50.

5. The preparation method according to claim 3, characterized in that, The hydrophobic layer solvent includes deionized water, ethanol, and acetic acid; the volume ratio of the deionized water, ethanol, and acetic acid is 1:(2~3):(7~10); the mass ratio of the hydrophobic component to the volume ratio of the hydrophobic layer solvent is (3~11)g:(10~20)mL.

6. The preparation method according to claim 3, characterized in that, The conditions for the first, second, and third electrospinning are independent and include: a voltage of 10-20 kV, a collector receiving distance of 5-20 cm, a collector rotation speed of 10-200 rpm, an injection pump injection rate of 0.2-20 mL / h, and a relative humidity of 10%-80%.

7. The application of the environmentally responsive smart release nanopesticide according to any one of claims 1 to 2 or the environmentally responsive smart release nanopesticide prepared by the preparation method according to any one of claims 3 to 6 in agriculture.

Images