PH (Potential of Hydrogen) and pectinase dual-response type pesticide microcapsule as well as preparation method and application thereof

Abstract

The invention discloses a pH and pectinase dual-response type pesticide microcapsule and a preparation method and application thereof.The pH and pectinase dual-response type pesticide microcapsule is of a core-shell structure, the core structure is prochloraz ionic liquid, and the shell structure sequentially comprises a metal-phenol network layer and a pectin layer from inside to outside; and the metal-phenol network layer is a tannic acid-copper network layer. In order to further strengthen long-term autonomous management of plant diseases and reduce the problem of pesticide leakage in a traditional spraying method to the maximum extent, the invention further provides an adhesive gel patch, agar hydrogel is used for stabilizing pesticide microcapsules, silicone rubber is used as a protective layer, and stable attachment of the patch to leaves is achieved by means of magnets. The preparation process of the pH and pectinase double-response type pesticide microcapsule and the adhesive gel patch thereof has the advantages of rapidness, economy, environmental protection and suitability for industrial production, and has huge potential in sustainable management of plant diseases and precision agriculture.

Description

Technical Field

[0001] The present invention relates to the technical field of pesticide microcapsules, and in particular to a pH and pectinase dual-responsive pesticide microcapsule and a preparation method and application thereof. Background Art

[0002] In agriculture, traditional pesticide formulations generally face the challenge of low utilization rates during field applications. During use, they are prone to spray drift, roll-off, runoff, dust drift, rainwater leaching, volatilization, and photolysis, resulting in over 90% of the pesticide's active ingredients failing to reach target organisms.

[0003] To address these challenges, nanopesticide technology has emerged. This technology can reduce pesticide degradation, enhance stability, reduce non-target toxicity, and effectively prolong pesticide persistence. By constructing pesticide delivery systems that release pesticides in response to stimuli such as enzymes, pH, temperature, and light, it is possible to maximize the synergistic effect of pesticide release characteristics and pest control dosage requirements. Currently, a wide variety of nanocarriers exist, including chitosan, pectin, silica, metal-phenol networks, calcium carbonate, and montmorillonite. Among these, metal-phenol networks are attracting increasing attention due to their advantages, including rapid synthesis under mild conditions, low cost, and green technology potential, which meet the technical requirements of agricultural applications.

[0004] Take prochloraz (PRO) as an example. As a broad-spectrum, highly effective imidazole fungicide, it is widely used in horticulture and agriculture. However, its poor systemic absorption, rapid photolysis, and high risk to aquatic environments limit its further application. Although PRO ionic liquids composed of PRO and docusate sodium can enhance the biological efficacy of PRO, and the tannic acid-copper network within the metal-phenol network has advantages such as strong adhesion, pH responsiveness, UV resistance, and antibacterial properties, the integration of PRO ionic liquid soft templates, tannic acid-copper networks, and pectin can also improve the application of PRO, most current nanopesticide research still faces problems of high cost and low safety.

[0005] Furthermore, when nanoparticles are sprayed onto plant leaves, micron-sized pores provide a pathway for them to enter the plant. However, the surface tension of water droplets causes the nanoparticles to aggregate toward the droplet's edges, reducing their dispersion. Water evaporation also hinders their diffusion. Although hydrogels can enhance the stability of nanoparticles, allowing them to slowly and steadily enter leaf tissue, the effective integration of nanopesticide technology with gel technology to achieve sustained and stable diffusion of nanoparticles, minimizing the impact of time and the external environment, and ultimately enabling autonomous plant disease management and green precision agriculture, remains an urgent challenge. Summary of the Invention

[0006] To solve the above technical problems, the present invention provides a pH and pectinase dual-responsive pesticide microcapsule and its preparation method and application, which combines nanopesticide technology and gel technology. The preparation process has the advantages of being fast, convenient, economical, environmentally friendly, highly safe and suitable for industrial production. The prepared pesticide microcapsule has good sealing performance for nanopesticides and has great potential in the sustainable management of plant diseases and precision agriculture, thereby realizing green precision agriculture.

[0007] The present invention is achieved through the following technical solutions:

[0008] The first aspect of the present invention provides a pH and pectinase dual-responsive pesticide microcapsule, which has a core-shell structure, wherein the core structure is a prochloraz ionic liquid, and the shell structure is a metal-phenol network layer and a pectin layer from the inside to the outside, wherein the metal-phenol network layer is a tannic acid-copper network layer.

[0009] The pH and pectinase dual-responsive pesticide microcapsules provided by the present invention use prochloraz ionic liquid (PRO IL) as a template material. Through double coating of a tannic acid-copper network layer and a pectin layer, the obtained pesticide microcapsules have a clear double-layer core-shell structure and can respond to oxalic acid and pectinase secreted by plant pathogens during the process of infecting plants, thereby achieving precise release of pesticides and reducing the loss of pesticides in the environment.

[0010] Furthermore, the diameter of the core structure is 100-150 nm, the thickness of the metal-phenol network layer is 50-100 nm, and the thickness of the pectin layer is 10-50 nm.

[0011] Preferably, the diameter of the core structure is 110-130 nm, the thickness of the metal-phenol network layer is 70-80 nm, and the thickness of the pectin layer is 15-30 nm.

[0012] The second aspect of the present invention provides a method for preparing the pH and pectinase dual-responsive pesticide microcapsules described in the first aspect, comprising the following steps: adding copper salt and tannic acid to a prochloraz ionic liquid emulsion to obtain a mixed emulsion, adjusting the pH value to 7.2-7.3 and stirring, adding pectin to the obtained suspension and stirring again to obtain the pH and pectinase dual-responsive pesticide microcapsules.

[0013] Furthermore, the prochloraz ionic liquid emulsion is prepared by mixing prochloraz ionic liquid, Tween 80 and water.

[0014] Furthermore, the concentration of the prochloraz ionic liquid in the prochloraz ionic liquid emulsion is 5-8 mM.

[0015] Furthermore, the mass concentration of Tween 80 in the prochloraz ionic liquid emulsion is 0.05-0.08%.

[0016] Tween 80 significantly improves the particle size and polydispersity index of prochloraz ionic liquid emulsions. Macroscopically, this results in a more pronounced liquid Tyndall effect and increased transparency. The statistically hydrated average particle size of the pH- and pectinase-responsive pesticide microcapsules can be altered by varying the concentration of Tween 80, enabling the preparation of submicron-sized nanopesticides with the nanoparticle effect.

[0017] Furthermore, the prochloraz ionic liquid, Tween 80 and water are mixed and stirred at 120-240 rpm to obtain the prochloraz ionic liquid emulsion.

[0018] In a specific embodiment, the prochloraz ionic liquid and Tween 80 are added to water and stirred at 120-240 rpm for 2-3 minutes to form a prochloraz ionic liquid emulsion that is stably and uniformly dispersed in the water.

[0019] Furthermore, the copper salt is a divalent copper salt.

[0020] Furthermore, the concentration of copper ions in the mixed emulsion is 0.07-0.11 mM.

[0021] Furthermore, the concentration of tannic acid in the mixed emulsion is 0.06-0.15 mg / mL.

[0022] Furthermore, the pH value is adjusted using 3-morpholinepropanesulfonic acid buffer or sodium hydroxide.

[0023] Furthermore, the pectin is citrus pectin, and the degree of esterification is 58-60%.

[0024] Furthermore, pectin is added to the obtained suspension to obtain a suspension solution, wherein the mass concentration of pectin in the suspension solution is 0.18-0.36%.

[0025] In a specific embodiment, copper salt and tannic acid are added to the prochloraz ionic liquid emulsion and stirred at 120-240 rpm for 2-3 minutes to obtain a mixed emulsion, the pH value is adjusted to 7.2-7.3 with 3-morpholinepropanesulfonic acid buffer and then stirred at 120-240 rpm for 2-3 minutes, pectin is added to the obtained PRO ionic liquid @ tannic acid-copper suspension and stirred at 120-240 rpm for 6-10 minutes to obtain a mixture, and the pH and pectinase dual-responsive pesticide microcapsules (PRO ionic liquid @ tannic acid-copper @ pectin) are obtained after centrifugation.

[0026] Furthermore, the centrifugal condition is 9000-12000 r / min for 3-4 min.

[0027] Furthermore, the centrifugation further includes a washing step.

[0028] In practical applications, the mixture can be sprayed directly without centrifugation. The materials used in the preparation process are free of environmental hazards and are all useful. Specifically, PRO ionic liquid@tannic acid-copper@pectin can be synthesized directly by adding various reagents to water without centrifugation, and then sprayed. This saves costs while maintaining the efficacy of PRO ionic liquid@tannic acid-copper@pectin. For example, excess PRO ionic liquid that has not been microencapsulated can exert some of its effect, and the presence of multiple surfactants can increase wettability and enhance retention on leaves.

[0029] The third aspect of the present invention provides a use of the pH and pectinase dual-responsive pesticide microcapsules described in the first aspect in pest control.

[0030] In order to further enhance the long-term autonomous management of plant diseases and minimize the problem of drug leakage in traditional spraying methods, the fourth aspect of the present invention provides an adhesive gel patch, which includes a first magnet, silicone rubber and a second magnet, the silicone rubber is between the first magnet and the second magnet, and agar hydrogel is arranged inside the silicone rubber, and the side of the agar hydrogel away from the second magnet is connected to the outside world; the agar hydrogel contains the pH and pectinase dual-responsive pesticide microcapsules described in the first aspect.

[0031] The adhesive gel patch provided by this invention utilizes agar hydrogel to stabilize pH and pectinase-responsive pesticide microcapsules, with silicone rubber as a protective layer. Magnets are used to stabilize the patch on leaves, with the leaf positioned between the first magnet and the silicone rubber. At the same PRO dosage, the patch method offers a longer self-regulation cycle than the spray method.

[0032] Furthermore, the second magnet may be fixedly connected by the adhesion of silicone rubber.

[0033] Furthermore, the material of the silicone rubber is two-component room temperature vulcanized silicone rubber.

[0034] Furthermore, the silicone rubber is made of room temperature vulcanized silicone rubber A and room temperature vulcanized silicone rubber B, the room temperature vulcanized silicone rubber A includes vinyl polydimethylsiloxane and methyl vinylsiloxane coordinated platinum complex, and the room temperature vulcanized silicone rubber B includes hydrogenated silicone oil and silicon dioxide.

[0035] Furthermore, the room temperature vulcanized silicone rubber A includes vinyl polydimethylsiloxane, methyl vinyl siloxane coordinated platinum complex, a release agent, a plasticizer and silicon dioxide.

[0036] Furthermore, the mass concentration of the vinyl polydimethylsiloxane in the room temperature vulcanized silicone rubber A is 50-65%, the mass concentration of the platinum element in the methyl vinyl siloxane coordinated platinum complex in the room temperature vulcanized silicone rubber A is 0.8-1%, the mass concentration of the release agent dimethyl silicone oil in the room temperature vulcanized silicone rubber A is 5-22%, the mass concentration of the plasticizer phthalate plasticizer in the room temperature vulcanized silicone rubber A is 2-8%, and the mass concentration of silicon dioxide in the room temperature vulcanized silicone rubber A is 12-21%.

[0037] Furthermore, the room temperature vulcanized silicone rubber B includes hydrogenated silicone oil, vinyl polydimethylsiloxane, a release agent, a plasticizer and silicon dioxide.

[0038] Furthermore, the hydrogen-containing silicone oil is a hydrogen-containing silicone oil with a low degree of polymerization (degree of polymerization less than 30).

[0039] Furthermore, the mass concentration of the hydrogen-containing silicone oil in the room temperature vulcanized silicone rubber B is 2.5-3.5%, the mass concentration of the vinyl polydimethylsiloxane in the room temperature vulcanized silicone rubber B is 30-70%, the mass concentration of the release agent dimethyl silicone oil in the room temperature vulcanized silicone rubber B is 4-25%, the mass concentration of the plasticizer phthalate plasticizer in the room temperature vulcanized silicone rubber B is 1-15%, and the mass concentration of the silicon dioxide in the room temperature vulcanized silicone rubber B is 12-30%.

[0040] Furthermore, the preparation method of the agar hydrogel comprises the following steps: mixing agar, Tween 80 and water, and adding pH and pectinase dual-responsive pesticide microcapsules to the obtained agar solution to obtain the agar hydrogel.

[0041] Furthermore, the mass concentration of agar in the agar solution is 0.25-0.3%, and the mass concentration of Tween 80 in the agar solution is 0.1-0.2%.

[0042] Furthermore, the concentration of the pH and pectinase dual-responsive pesticide microcapsules in the agar hydrogel is 0.32-0.48 g / L.

[0043] In a specific embodiment, the method for preparing the adhesive gel patch comprises the following steps:

[0044] (1) Prepare a mold, seal the bottom of the mold with a magnet, and insert a solid that is smaller than the mold to ensure the existence of the cavity.

[0045] (2) Room temperature vulcanized silicone rubber A and room temperature vulcanized silicone rubber B are mixed in a volume ratio of 1:1 and injected into a mold, and after cooling, a shell of an adhesive gel patch with a magnet is obtained.

[0046] (3) Adding agar hydrogel into the cavity of silicone rubber and cooling to obtain the adhesive gel patch.

[0047] In order to ensure the efficient production of adhesive gel patches, multiple mold pools can be arranged in parallel into a large mold assembly, and liquid inlets can be set to achieve the purpose of mass production.

[0048] In practical applications, due to the reusability and convenient recycling of silicone rubber and magnets, when the effect of agar hydrogel decreases, it can be injected again and reused.

[0049] Beneficial effects of the present invention:

[0050] 1. The present invention designs and constructs a smart pH and pectinase dual-responsive pesticide microcapsule, and further develops an adhesive gel patch based on the microcapsule for realizing long-term autonomous management of plant diseases. The preparation method of the pH-responsive and pectinase dual-responsive pesticide microcapsule and its adhesive gel patch provided by the present invention is simple, low-cost, and highly safe, and has great potential for current nanopesticide applications. Due to the speed and safety of the pH-responsive and pectinase dual-responsive pesticide microcapsule preparation system, nanopesticides can be prepared according to the actual situation on site and sprayed onto the target plants, which has the advantages of being suitable for actual production and saving costs. The adhesive gel patch ensures a longer nanopesticide lasting period, and there is no risk of drug leakage. The total amount of the drug is also within a controllable range, and it is convenient, safe, low-cost and recyclable.

[0051] 2. The pH response and pectinase dual-responsive pesticide microcapsules provided by the present invention have a layered structure, and the PRO loading rate is 25.93±1.81%. The pesticide microcapsules show significant pH responsiveness and pectinase responsiveness, which is conducive to the precise release of PRO, and have a higher PRO loading capacity, as well as higher photostability than commercially available PRO reagents (such as Qiyun-PRO EW), which is 1.33 times that of commercially available PRO reagents. Bactericidal tests show that the control effect of the pH response and pectinase dual-responsive pesticide microcapsules is 1.47 times that of commercially available PRO reagents. When using sclerotinia and cabbage-type rapeseed as disease bacteria and crop models, the control effect of the microcapsules is higher than that of commercially available PRO reagents, and the lasting effect is greatly extended. Potted experiments show that the control effect of the pH response and pectinase dual-responsive pesticide microcapsules is 2.98 times that of commercially available PRO reagents. The adhesive gel patch can adhere to the leaves, well protecting the internal agar hydrogel and without damaging the leaves. At the same dose of PRO, the adhesive gel patch prolonged the self-administration period by 2 times compared with the spray method. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1Schematic diagram of the preparation and application of pH and pectinase dual-responsive pesticide microcapsules provided by the present invention; wherein, a is a schematic diagram of the preparation of pH and pectinase dual-responsive pesticide microcapsules, and b is a schematic diagram of the application of pH and pectinase dual-responsive pesticide microcapsules.

[0053] Figure 2 This is a scanning electron microscope image of the pH and pectinase dual-responsive pesticide microcapsules prepared in Example 1.

[0054] Figure 3 This is a transmission electron microscope image of the pH and pectinase dual-responsive pesticide microcapsules prepared in Example 1.

[0055] Figure 4 This is a data graph of the encapsulation efficiency of the pH and pectinase dual-responsive pesticide microcapsules prepared in Examples 1-5.

[0056] Figure 5 This is a data graph showing the drug loading rate of the pH and pectinase dual-responsive pesticide microcapsules prepared in Example 1 and Examples 6-9.

[0057] Figure 6 This is a mold design diagram for preparing an adhesive gel patch; among them, a is a schematic diagram of the liquid filling, cooling and forming of silicone rubber, and b is a schematic diagram of the cooling and forming of agar hydrogel on silicone rubber.

[0058] Figure 7 This is a design drawing of the adhesive gel patch prepared in Example 10 and a schematic diagram of its application to plant leaves.

[0059] Figure 8 This is a physical picture of the adhesive gel patch prepared in Example 10. DETAILED DESCRIPTION

[0060] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0061] The first aspect of the present invention provides a pH and pectinase dual-responsive pesticide microcapsule, which has a core-shell structure, wherein the core structure is a prochloraz ionic liquid, and the shell structure is a metal-phenol network layer and a pectin layer from the inside to the outside, wherein the metal-phenol network layer is a tannic acid-copper network layer.

[0062] The second aspect of the present invention provides a method for preparing a pH and pectinase dual-responsive pesticide microcapsule, as shown in the schematic diagram. Figure 1As shown in a, the process comprises the following steps: adding copper salt and tannic acid to a prochloraz ionic liquid emulsion to obtain a mixed emulsion, adjusting the pH value to 7.2-7.3 and stirring, adding pectin to the obtained suspension and stirring again to obtain the pH and pectinase dual-responsive pesticide microcapsules.

[0063] The third aspect of the present invention is the application of a pH and pectinase dual-responsive pesticide microcapsule in pest control, as shown in the schematic diagram Figure 1 As shown in b, it can be used by spraying, which has the disadvantages of short hazard prevention and control time and drug leakage; it can also be made into an adhesive gel patch and adhered to the leaves, which has the advantages of long hazard prevention and control time and no drug leakage.

[0064] A fourth aspect of the present invention provides an adhesive gel patch, comprising a first magnet, silicone rubber, and a second magnet, wherein the silicone rubber is between the first magnet and the second magnet, and agar hydrogel is disposed inside the silicone rubber, wherein the side of the agar hydrogel away from the second magnet is connected to the outside world; the agar hydrogel contains the pH and pectinase dual-responsive pesticide microcapsules described in the first aspect.

[0065] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention.

[0066] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, and the materials and reagents used are all commercially available unless otherwise specified.

[0067] Example 1

[0068] A method for preparing pH and pectinase dual-responsive pesticide microcapsules (PRO ionic liquid@tannic acid-copper@pectin) comprises the following steps:

[0069] S1. PRO ionic liquid and Tween 80 were added to 15 mL of water and stirred at 240 rpm for 2 min to form a PRO ionic liquid emulsion stably and uniformly dispersed in water, wherein the concentration of PRO ionic liquid in the PRO ionic liquid emulsion was 5 mM and the mass concentration of Tween 80 in the PRO ionic liquid emulsion was 0.05%.

[0070] S2. Add copper sulfate and tannic acid to the PRO ionic liquid emulsion to form a mixed emulsion. The copper ion concentration in the mixed emulsion is 0.11 mM, and the tannic acid concentration in the mixed emulsion is 0.12 mg / mL. Vortex the mixture for 2 minutes. Adjust the pH to 7.2 with 3-morpholinepropanesulfonic acid buffer, and stir at 240 rpm for 3 minutes to obtain a PRO ionic liquid-tannic acid-copper suspension.

[0071] S3. Pectin was added to the PRO ionic liquid@tannic acid-copper suspension to obtain a suspension solution having a pectin concentration of 0.28%. The suspension solution was stirred at 240 rpm for 6 min to obtain a mixture, which was then centrifuged at 9000 rpm for 3 min to obtain the pH and pectinase dual-responsive pesticide microcapsules (PRO ionic liquid@tannic acid-copper@pectin).

[0072] Figure 2 This is a scanning electron microscope image of the pH and pectinase dual-responsive pesticide microcapsules prepared in Example 1. Figure 3 This is a transmission electron microscope image of the pH and pectinase dual-responsive pesticide microcapsules prepared in Example 1. It can be seen that PRO ionic liquid@tannic acid-copper@pectin has a clear core-shell structure.

[0073] Example 2

[0074] A preparation method of pH and pectinase dual-responsive pesticide microcapsules (PRO ionic liquid@tannic acid-copper@pectin) is basically the same as that in Example 1, except that in S2, the concentration of tannic acid in the mixed emulsion is 0.03 mg / mL.

[0075] Example 3

[0076] A preparation method of a pH and pectinase dual-responsive pesticide microcapsule (PRO ionic liquid@tannic acid-copper@pectin) is basically the same as that in Example 1, except that in S2, the concentration of tannic acid in the mixed emulsion is 0.06 mg / mL.

[0077] Example 4

[0078] A preparation method of pH and pectinase dual-responsive pesticide microcapsules (PRO ionic liquid@tannic acid-copper@pectin) is basically the same as that in Example 1, except that in S2, the concentration of tannic acid in the mixed emulsion is 0.09 mg / mL.

[0079] Example 5

[0080] A preparation method of a pH and pectinase dual-responsive pesticide microcapsule (PRO ionic liquid@tannic acid-copper@pectin) is basically the same as that in Example 1, except that in S2, the concentration of tannic acid in the mixed emulsion is 0.15 mg / mL.

[0081] The encapsulation efficiency of the pH and pectinase dual-responsive pesticide microcapsules prepared in Examples 1-5 was calculated. The encapsulation efficiency was the ratio of the PRO content in the PRO ionic liquid @ tannic acid-copper @ pectin obtained by centrifugation to the PRO content in the total solution system. The data is shown in the figure below. Figure 4As shown in the figure, with the increase of tannic acid concentration, the encapsulation efficiency gradually increased and reached a peak value of nearly 45% at 0.12 mg / mL.

[0082] Example 6

[0083] A preparation method of pH and pectinase dual-responsive pesticide microcapsules (PRO ionic liquid@tannic acid-copper@pectin) is basically the same as that of Example 1, except that in S3, the mass concentration of pectin in the suspension solution is 0.07%.

[0084] Example 7

[0085] A preparation method of pH and pectinase dual-responsive pesticide microcapsules (PRO ionic liquid@tannic acid-copper@pectin) is basically the same as that of Example 1, except that in S3, the mass concentration of pectin in the suspension solution is 0.14%.

[0086] Example 8

[0087] A preparation method of pH and pectinase dual-responsive pesticide microcapsules (PRO ionic liquid@tannic acid-copper@pectin) is basically the same as that of Example 1, except that in S3, the mass concentration of pectin in the suspension solution is 0.21%.

[0088] Example 9

[0089] A preparation method of pH and pectinase dual-responsive pesticide microcapsules (PRO ionic liquid@tannic acid-copper@pectin) is basically the same as that of Example 1, except that in S3, the mass concentration of pectin in the suspension solution is 0.35%.

[0090] The loading rate of the pH and pectinase dual-responsive pesticide microcapsules prepared in Example 1 and Examples 6-9 was calculated. The loading rate is the mass ratio of PRO in the pesticide microcapsules. The data is shown in the figure below. Figure 5 As shown in the figure, the drug loading rate gradually decreases with the increase of pectin concentration, and the trend slows down at 0.30%. This may be because the adsorption of pectin has a saturation value and cannot increase with increasing concentration. It also depends on the particle size and morphology, etc.

[0091] Example 10

[0092] A method for preparing a PRO ionic liquid@tannic acid-copper@pectin adhesive gel patch comprises the following steps:

[0093] (1) The mold is designed to be cylindrical with a bottom diameter of 2 cm and a depth of 1 cm. The bottom of the mold is sealed with a magnet (a cylinder with a bottom diameter of 1.6 cm and a height of 0.2 cm). In order to ensure the existence of the cavity, a magnet with a bottom diameter of 1 cm and a volume of 1.5 cm needs to be inserted in advance. 3 of a cylinder.

[0094] (2) The main components of room temperature vulcanized silicone rubber A are vinyl polydimethylsiloxane (60% by mass), methyl vinyl siloxane coordinated platinum complex (catalyst, platinum element mass concentration of 1%), mold release agent dimethyl silicone oil (15% by mass), plasticizer phthalate plasticizer (6% by mass), and silicon dioxide (18% by mass). The main components of room temperature vulcanized silicone rubber B are low-polymerization hydrogen-containing silicone oil (3% by mass), silicon dioxide (12% by mass), vinyl polydimethylsiloxane (65% by mass), mold release agent dimethyl silicone oil (10% by mass), and plasticizer phthalate plasticizer (10% by mass). Room temperature vulcanized silicone rubber A and room temperature vulcanized silicone rubber B are mixed in a volume ratio of 1:1 and injected into a mold. The cavity is pressed to form a cylinder. The magnet can be fixedly connected through the adhesion of the silicone rubber. After cooling, the shell of the adhesive gel patch with the magnet is obtained.

[0095] (3) Agar, Tween 80, and water were mixed to obtain 1.5 mL of an agar solution, wherein the mass concentration of agar in the agar solution was 0.3%, and the mass concentration of Tween 80 in the agar solution was 0.1%. The pH and pectinase dual-responsive pesticide microcapsules prepared in Example 1 were added to the agar solution to obtain an agar hydrogel, wherein the concentration of the pH and pectinase dual-responsive pesticide microcapsules was 0.38 g / L. The agar hydrogel was added to the cavity of the silicone rubber and cooled to obtain the PRO ionic liquid@tannic acid-copper@pectin adhesive gel patch.

[0096] Figure 6 This is a mold design diagram for preparing an adhesive gel patch; among them, a is a schematic diagram of the liquid filling, cooling and forming of silicone rubber, and b is a schematic diagram of the cooling and forming of agar hydrogel on silicone rubber.

[0097] Figure 7 This is a design diagram of the adhesive gel patch prepared in Example 10 and a schematic diagram of its application to plant leaves. The PRO ionic liquid@tannic acid-copper@pectin in the adhesive gel patch can diffuse steadily and slowly through the stomata into the leaf tissue.

[0098] Figure 8 This is a physical picture of the adhesive gel patch prepared in Example 10. The adhesive gel patch can be adhered to the leaves quickly and without damage. The rapeseed leaves are not damaged after long-term adhesion, and the internal hydrogel maintains a high water content.

[0099] Comparative Example 1

[0100] A method for preparing PRO ionic liquid@calcium carbonate@pectin pesticide capsules (DOI: 10.1016 / j.cej.2022.137073) comprises the following steps:

[0101] First, PRO IL was dispersed in a 0.20M CaCl2 solution to form a 4.50mM emulsion. A 0.20M Na2CO3 aqueous solution was then added to the mixed solution while stirring at 300rpm. After stirring for approximately 60min, single-shell microcapsules (PROIL@CaCO3 microcapsules) were obtained. Subsequently, 2.0mg / mL of pectin solutions of varying concentrations were added dropwise to the suspension under stirring to form double-shell microcapsules (PRO IL@CaCO3@pectin microcapsules). After stirring for another 30 minutes, the suspension was allowed to stand at room temperature for 60 minutes. The experimental suspension was centrifuged and washed three times with deionized water to obtain PRO ionic liquid@calcium carbonate@pectin pesticide capsules.

[0102] Compared with the PRO ionic liquid @ calcium carbonate @ pectin pesticide capsules of Comparative Example 1, the pH and pectinase dual-responsive pesticide microcapsules prepared in Example 1 of the present invention have an average hydrated particle size of 370 nm, a drug loading rate of 25.9%, and a sclerotinia disease control effect that is 2.98 times that of the commercially available Qiyun-PRO EW reagent. The PRO ionic liquid @ calcium carbonate @ pectin pesticide capsules of Comparative Example 1 have an average hydrated particle size of 4.72 μm, a drug loading rate of 6.4%, and a sclerotinia disease control effect that is 1.65 times that of the commercially available Huifeng-PRO EW reagent. Small particle size has a stronger advantage in the biological effect of pesticide microcapsules. The preparation time of Comparative Example 1 is several hours, while Example 1 only takes more than ten minutes. The shorter time is conducive to rapid preparation and use according to the on-site conditions of the farmland.

[0103] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations or modifications may be made based on the above description. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A pH and pectinase dual-responsive pesticide microcapsule, characterized in that: The pH and pectinase dual-responsive pesticide microcapsules are core-shell structures, wherein the core structure is prochloraz ionic liquid, and the shell structure is a metal-phenol network layer and a pectin layer from the inside to the outside, wherein the metal-phenol network layer is a tannic acid-copper network layer.

2. A method for preparing pH and pectinase dual-responsive pesticide microcapsules, characterized in that: The following steps are involved: Copper salt and tannic acid are added to the prochloraz ionic liquid emulsion to obtain a mixed emulsion, the pH value is adjusted to 7.2-7.3 and then stirred, pectin is added to the obtained suspension and stirred again to obtain the pH and pectinase dual-responsive pesticide microcapsules.

3. The preparation method according to claim 2, characterized in that The prochloraz ionic liquid emulsion is prepared by mixing prochloraz ionic liquid, Tween 80 and water; the concentration of the prochloraz ionic liquid in the prochloraz ionic liquid emulsion is 5-8 mM.

4. The preparation method according to claim 2, characterized in that The concentration of copper ions in the mixed emulsion is 0.07-0.11 mM.

5. The preparation method according to claim 2, characterized in that The concentration of tannic acid in the mixed emulsion is 0.06-0.15 mg / mL.

6. The preparation method according to claim 2, characterized in that Pectin is added to the obtained suspension to obtain a suspension solution, wherein the mass concentration of pectin in the suspension solution is 0.18-0.36%.

7. Use of the pH and pectinase dual-responsive pesticide microcapsules according to claim 1 or the pH and pectinase dual-responsive pesticide microcapsules prepared by the preparation method according to claim 2 in pest control.

8. An adhesive gel patch, characterized in that The adhesive gel patch includes a first magnet, silicone rubber and a second magnet, the silicone rubber is between the first magnet and the second magnet, agar hydrogel is arranged inside the silicone rubber, and the side of the agar hydrogel away from the second magnet is connected to the outside world; the agar hydrogel contains the pH and pectinase dual-responsive pesticide microcapsules described in claim 1 or the pH and pectinase dual-responsive pesticide microcapsules prepared by the preparation method according to claim 2.

9. The adhesive gel patch according to claim 8, characterized in that The silicone rubber is made of room temperature vulcanized silicone rubber A and room temperature vulcanized silicone rubber B. The room temperature vulcanized silicone rubber A comprises vinyl polydimethylsiloxane and methylvinylsiloxane coordinated platinum complex, and the room temperature vulcanized silicone rubber B comprises hydrogenated silicone oil and silicon dioxide.

10. The adhesive gel patch according to claim 8, characterized in that Agar, Tween 80 and water are mixed, and pH and pectinase dual-responsive pesticide microcapsules are added to the obtained agar solution to obtain the agar hydrogel; the concentration of the pH and pectinase dual-responsive pesticide microcapsules in the agar hydrogel is 0.32-0.48 g / L.

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