Nano pesticide preparation for preventing and treating panonychus citri and preparation method thereof
By encapsulating matrine and spirotetramat using iron-based organic metal framework nanomaterials and modifying them with polyethyleneimine and dioctyl sodium sulfosuccinate, the prepared nanopesticide formulation solves the problems of low drug stability and transmission efficiency, improves the control effect of citrus mites, and realizes the efficient utilization of the drug solution.
Patent Information
- Application Number
- CN202510792245.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-13
- Publication Date
- 2025-09-26
AI Technical Summary
Existing acaricides have problems in the control of citrus mites, such as poor drug stability, low transmission efficiency, insufficient retention, and easy development of drug resistance, resulting in low efficiency of drug solution utilization and difficulty in effectively controlling pests.
Matrine and spirotetramat were encapsulated using iron-based organometallic framework nanomaterials and modified with polyethyleneimine and dioctyl sodium sulfosuccinate to prepare a nanopesticide formulation that improved the retention time and transmission efficiency of the pesticide solution on citrus leaves.
It increases the retention of liquid medicine on citrus leaves, enhances the utilization rate of liquid medicine, reduces the amount of medicine used, reduces the risk of pest resistance, and achieves the effect of reducing the amount and increasing the efficiency of prevention and control.
Smart Images
Figure CN120694267A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of nanopesticides, and in particular to a nanopesticide preparation for preventing and controlling Panonychus citrus mites and a preparation method thereof. Background Art
[0002] The citrus mite (Panonychus citri) belongs to the Arachnida, Acari, Tetranychus, and Panonychus genus. Adults, nymphs, and larvae use their mouthparts to suck sap from leaves, green branches, and the skin of fruit. Leaves are most severely affected, with numerous small grayish-white spots appearing on the affected leaves. In severe cases, the entire leaf loses its green color and turns grayish-white, leading to extensive leaf drop. It can also infest fruit and green branches, impacting tree vigor and yield. It is a leading pest in my country's citrus production. Conventional control methods primarily include chemical and biological control.
[0003] Matrine and spirotetramat are two common agents currently used to control Panonychus citrifolia. Matrine, an alkaloid extracted from the roots, leaves, and nuts of the leguminous plant Sophora flavescens using organic solvents such as ethanol, is a natural botanical pesticide with low toxicity to humans and animals. It possesses a broad spectrum of control, exhibits contact and gastric toxicity, and is effective against armyworms, cabbage loopers, aphids, and spider mites on various crops. Spirotetramat is a highly effective, broad-spectrum, and low-toxic insecticide and acaricide, and its excellent bidirectional systemic transport properties make it a promising acaricide. However, matrine is unstable and easily degrades in organic solvents, while spirotetramat is highly photolytic, and its hydrophobic nature results in low transport efficiency and slow crop absorption. Furthermore, when these two agents are applied in traditional pesticide formulations, the poor retention of the pesticide solution on plant leaves leads to significant loss of pesticide droplets, resulting in low pesticide utilization efficiency. High dosages are required during peak infestation periods, making them susceptible to the development of pesticide resistance.
[0004] Therefore, based on the severe situation currently faced by insecticides and acaricides in use, it is urgent to develop new drug formulations in order to achieve the maximum acaricidal efficiency with the minimum drug dosage, while reducing the resistance of mites to drugs and realizing the development path of sustainable green agriculture. Summary of the Invention
[0005] In response to the above-mentioned prior art, the present invention aims to provide a nanopesticide formulation and preparation method for controlling Panonychus citri. This invention encapsulates a pesticide with acaricidal activity within an iron-based organometallic framework. A polyethyleneimine film is then coated on the surface of the iron-based organometallic framework nanopesticide, imparting a strong positive charge. Dioctyl sodium sulfosuccinate is then adsorbed via this charge, resulting in a novel nanopesticide formulation for controlling Panonychus citri. This formulation can increase the retention time of the pesticide on leaf surfaces during spraying, thereby achieving the goal of reducing spray dosage and increasing efficacy.
[0006] To achieve the above object, the present invention adopts the following technical solutions:
[0007] The first aspect of the present invention provides a nanopesticide formulation for controlling Panonychus citri, which is prepared by the following method:
[0008] (1) dispersing an iron-based metal-organic framework nanomaterial in a pesticide having acaricidal activity, stirring in the dark, collecting a precipitate by centrifugation, washing, and drying the precipitate to prepare an iron-based metal-organic framework nanomaterial loaded with a pesticide;
[0009] (2) The iron-based metal organic framework nanomaterial loaded with pesticides is dispersed in deionized water, and a polyethyleneimine aqueous solution is added and stirred to form a polyethyleneimine film on the surface of the iron-based metal organic framework nanomaterial loaded with pesticides. The material is purified by centrifugation and then dispersed in deionized water. Dioctyl sodium sulfosuccinate is added and stirred. Dioctyl sodium sulfosuccinate is adsorbed by charge action to prepare a nanopesticide preparation for controlling citrus mites.
[0010] Preferably, in step (1), the iron-based metal organic framework nanomaterial is prepared by the following method:
[0011] Ferric chloride hexahydrate is added into deionized water, stirred and dissolved, and then fumaric acid is added to react in a water bath, and a precipitate is collected by centrifugation. The precipitate is washed and dried to prepare an iron-based metal organic framework nanomaterial.
[0012] More preferably, the mass ratio of the added ferric chloride hexahydrate to the fumaric acid is (8-10):4.
[0013] More preferably, the temperature of the water bath reaction is 50-65° C., and the water bath reaction time is 4-48 h.
[0014] More preferably, the centrifugal speed is 3000-11000 rpm, and the centrifugal time is 10-30 min.
[0015] Preferably, in step (1), the pesticides having acaricidal activity are matrine and spirotetramat.
[0016] Preferably, in step (1), the weight ratio of the pesticide having acaricidal activity to the iron-based metal organic framework nanomaterial is (100-200):(10-20).
[0017] Preferably, in step (2), the weight ratio of the pesticide-loaded iron-based metal organic framework nanomaterial to the polyethyleneimine is (10-20): (0.1-1).
[0018] Preferably, in step (2), the weight ratio of the iron-based metal organic framework nanomaterial loaded with pesticide to dioctyl sodium sulfosuccinate is (10-20): 1
[0019] The second aspect of the present invention provides the use of the above-mentioned nanopesticide formulation in controlling Panonychus citri.
[0020] Beneficial effects of the present invention:
[0021] (1) The iron-based organometallic framework (OMF) prepared by the present invention is uniform in size and, upon degradation, produces iron ions that supplement plant nutrition, making it eco-friendly. Furthermore, the OMF can be used to observe the transport trajectory and duration of nanobiological agents on host plants using real-time magnetic resonance imaging, enabling precise tracking and control of the drugs.
[0022] (2) The present invention uses an iron-based organic metal framework to encapsulate matrine and spirotetramat, and then uses polyethyleneimine and dioctyl sodium sulfosuccinate for surface modification to prepare a nanopesticide formulation for controlling citrus mites, thereby increasing the retention of the solution on citrus leaves and thereby improving the utilization rate of the solution, thereby achieving the purpose of reducing the amount and increasing the efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 This is a sample of iron-based metal organic framework nanoparticles prepared in Example 1 of the present invention (the left picture is a wet sample, and the right picture is a powder sample).
[0024] Figure 2 This is a transmission electron microscope morphology image of the iron-based metal organic framework nanoparticles prepared in Example 1 of the present invention.
[0025] Figure 3 This is the pore size distribution diagram of the iron-based metal organic framework nanoparticles prepared in Example 1 of the present invention.
[0026] Figure 4 Fluorescence distribution of the iron-based metal-organic framework nanoparticles prepared in Example 1 of the present invention in the main veins of citrus leaves; the scale of the left figure is 50 μm, and the scale of the right figure is 100 μm.
[0027] Figure 5 This is a fluorescence image of the iron-based metal organic framework nanoparticles prepared in Example 1 of the present invention in the tissue section of Panonychus citri. DETAILED DESCRIPTION
[0028] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.
[0029] Terminology Notes:
[0030] The "room temperature" in the present invention refers to a temperature of 15°C to 35°C.
[0031] As previously mentioned, during the pesticide spraying process, droplets need to wet and spread so that the active ingredients can be evenly distributed on the target surface to exert their biological activity. However, during spraying, traditional pesticide droplets are lost due to poor retention on plant leaf surfaces, resulting in low liquid utilization efficiency.
[0032] In light of this, the present invention has developed a nanopesticide formulation for controlling Panonychus citri. The nanopesticide formulation uses iron-based metal-organic framework nanoparticles as a drug carrier, encapsulating matrine or spirotetramat for controlling Panonychus citri. The encapsulated iron-based metal-organic framework material is then surface-modified with polyethyleneimine and dioctyl sodium sulfosuccinate to produce the nanopesticide formulation for controlling Panonychus citri. This nanopesticide formulation improves the retention of the drug solution on citrus leaves, thereby increasing drug solution utilization and achieving the goal of reducing dosage and increasing efficiency.
[0033] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the technical solution of the present application will be described in detail below with reference to specific embodiments.
[0034] The test materials used in the examples of the present invention are all conventional test materials in the field and can be purchased through commercial channels. Experimental methods without detailed conditions were carried out according to conventional test methods or the operating instructions recommended by the supplier.
[0035] Example 1: Preparation of iron-based metal organic framework nanoparticles
[0036] Add 2.7 g of ferric chloride hexahydrate to 50 mL of deionized water and stir at room temperature for 10 minutes to completely dissolve the ferric chloride hexahydrate. While stirring, add 1.2 g of fumaric acid and continue stirring for 15 minutes to thoroughly mix. Place the mixture in a 65°C water bath and stir for 10 hours. Centrifuge at 5000 rpm for 15 minutes, and wash the precipitate five times with deionized water to remove any unreacted material. The purified support is freeze-dried to yield an orange powder, the iron-based metal-organic framework nanoparticles.
[0037] The actual photo of the iron-based metal organic framework nanoparticles prepared in this example is shown in FIG. Figure 1 As shown; the transmission electron microscopy morphology of iron-based metal organic framework nanoparticles is shown Figure 2 As shown; the pore size distribution diagram is as follows Figure 3 shown.
[0038] Example 2: Preparation of a nanopesticide formulation for controlling Panonychus citri
[0039] (1) 200 mg of spirotetramat was dissolved in 10 mL of anhydrous ethanol, to which 10 mg of the iron-based metal-organic framework nanoparticles prepared in Example 1 were added. The mixture was ultrasonically dispersed uniformly and stirred in the dark for 48 h. The mixture was centrifuged and the precipitate was washed three times with anhydrous ethanol to remove unadsorbed spirotetramat. The washed precipitate was dispersed in water and freeze-dried for 48 h to obtain an iron-based metal-organic framework material encapsulating spirotetramat.
[0040] (2) 20 mg of the iron-based metal organic framework material encapsulating spirotetramat was dispersed in 25 mL of deionized water, 1 mL of a 1 mg / mL polyethyleneimine aqueous solution was added, and the mixture was stirred for 12 h. The polyethyleneimine film was coated on the surface of the iron-based metal organic framework material encapsulating spirotetramat. The precipitate was collected by centrifugation and purified. The purified precipitate was then dispersed in 25 mL of deionized water, 0.5 mL of a 10 mg / mL dioctyl sodium sulfosuccinate aqueous solution was added, and the mixture was magnetically stirred for 12 h to prepare a nanopesticide preparation for controlling citrus mites.
[0041] Example 3: Preparation of a nanopesticide formulation for controlling Panonychus citri
[0042] (1) 100 mg of matrine was dissolved in 20 mL of methanol, to which 20 mg of the iron-based metal-organic framework nanoparticles prepared in Example 1 were added, and the mixture was uniformly dispersed by ultrasonication. The mixture was stirred in the dark for 48 h. The mixture was centrifuged, and the precipitate was washed three times with methanol to remove unadsorbed matrine. The washed precipitate was dispersed in water and freeze-dried for 48 h to obtain an iron-based metal-organic framework material encapsulating matrine.
[0043] (2) 10 mg of the iron-based metal organic framework material encapsulating matrine was dispersed in 10 mL of deionized water, 200 μL of a 1 mg / mL polyethyleneimine aqueous solution was added, and the mixture was stirred for 12 h. The polyethyleneimine film was coated on the surface of the iron-based metal organic framework material encapsulating matrine. The mixture was purified by centrifugation and then dispersed in 10 mL of deionized water. 1.5 ml of a 10 mg / mL dioctyl sodium sulfosuccinate aqueous solution was added, and the mixture was magnetically stirred for 12 h to prepare a nanopesticide preparation for controlling citrus mites.
[0044] Comparative Example 1:
[0045] 200 mg of spirotetramat was dissolved in 10 mL of anhydrous ethanol. 10 mg of the iron-based metal-organic framework nanoparticles prepared in Example 1 was added to the solution and ultrasonically dispersed uniformly. The mixture was stirred in the dark for 48 hours. The mixture was centrifuged, and the precipitate was washed three times with anhydrous ethanol to remove unadsorbed spirotetramat. The washed precipitate was dispersed in water and freeze-dried for 48 hours to obtain an iron-based metal-organic framework material encapsulating spirotetramat.
[0046] 20 mg of the iron-based metal-organic framework material encapsulating spirotetramat was dispersed in 25 mL of deionized water to obtain pesticide solution A.
[0047] Comparative Example 2:
[0048] 200 mg of spirotetramat was dissolved in 10 mL of anhydrous ethanol. 10 mg of the iron-based metal-organic framework nanoparticles prepared in Example 1 was added to the solution and ultrasonically dispersed uniformly. The mixture was stirred in the dark for 48 hours. The mixture was centrifuged, and the precipitate was washed three times with anhydrous ethanol to remove unadsorbed spirotetramat. The washed precipitate was dispersed in water and freeze-dried for 48 hours to obtain an iron-based metal-organic framework material encapsulating spirotetramat.
[0049] 20 mg of the iron-based metal-organic framework material encapsulating spirotetramat was dispersed in 25 mL of deionized water, 1 mL of a 1 mg / mL polyethyleneimine aqueous solution was added, and the mixture was stirred for 12 h. The precipitate was collected by centrifugation and purified, and the purified precipitate was dispersed in 25 mL of deionized water to obtain pesticide solution B.
[0050] Comparative Example 3:
[0051] 200 mg of spirotetramat was dissolved in 10 mL of anhydrous ethanol. 10 mg of the iron-based metal-organic framework nanoparticles prepared in Example 1 was added to the solution and ultrasonically dispersed uniformly. The mixture was stirred in the dark for 48 hours. The mixture was centrifuged, and the precipitate was washed three times with anhydrous ethanol to remove unadsorbed spirotetramat. The washed precipitate was dispersed in water and freeze-dried for 48 hours to obtain an iron-based metal-organic framework material encapsulating spirotetramat.
[0052] 20 mg of the iron-based metal organic framework material encapsulating spirotetramat was dispersed in 25 mL of deionized water, 0.5 mL of a 10 mg / mL aqueous solution of dioctyl sodium sulfosuccinate was added, and the mixture was magnetically stirred for 12 h to obtain pesticide solution C.
[0053] Test Example 1: Determination of the amount of pesticide solution retained on the surface of citrus leaves
[0054] 1. Test method:
[0055] Citrus leaves were cut into 1.5 cm x 1.5 cm squares. The mass of the fresh leaves was measured using an analytical balance, recorded as M1. The leaves were then immersed in the pesticide solutions prepared in Example 2 and Comparative Examples 1-3 for 15 seconds. The leaves were then removed and hung vertically until no more droplets fell. The mass of the leaves was then measured and recorded as M2. All tests were repeated at least ten times, and the amount of pesticide solution retained on the citrus leaf surface was calculated using the following formula.
[0056] Q=(M2-M1) / S
[0057] Where: Q represents the amount of pesticide solution retained on the surface of citrus leaves, in mg / cm 2 ; S represents the surface area of citrus leaves, in cm 2 .
[0058] 2. Test results:
[0059] The results are shown in Table 1.
[0060] Table 1: Retention of different pesticide solutions on the surface of citrus leaves
[0061]
[0062]
[0063] The retention of pesticide solutions on plant leaves significantly affects their biological effects in pest control. These results demonstrate that the present invention, through modification of the drug-encapsulating iron-based metal-organic framework with polyethyleneimine and dioctyl sodium sulfosuccinate, significantly increases the retention of pesticide solutions on citrus leaf surfaces, demonstrating a synergistic effect compared to modification with polyethyleneimine or dioctyl sodium sulfosuccinate alone.
[0064] Experimental Example 2: Distribution of Iron-Based Metal-Organic Framework Materials in Citrus Leaves and Panonychus citri
[0065] 1. Test method:
[0066] (1) Preparation of fluorescently labeled iron-based metal-organic framework materials
[0067] 50 mL of a 100 mg / L fluorescein isothiocyanate aqueous solution was prepared, and 25 mg of the iron-based metal-organic framework nanoparticles prepared in Example 1 were dispersed into the fluorescein isothiocyanate solution and ultrasonicated for 10 min to ensure full dispersion. The above system was stirred in the dark for 10 h, centrifuged, and the precipitate was washed three times with deionized water to remove unadsorbed fluorescein isothiocyanate. The precipitate was then freeze-dried to obtain an orange-yellow powder, which was the fluorescently labeled iron-based metal-organic framework nanoparticles.
[0068] The fluorescently labeled iron-based metal organic framework nanoparticles were dispersed in deionized water to prepare a solution with a concentration of 0.8 mg / ml for later use.
[0069] (2) Investigation of the distribution of iron-based metal-organic framework nanoparticles in citrus leaves
[0070] The prepared fluorescently labeled iron-based metal-organic framework nanoparticle solution was directly sprayed on citrus leaves. After being placed in the dark for 1 hour, the fluorescence distribution in the main veins of the citrus leaves was observed.
[0071] (3) Investigation of the distribution of iron-based metal organic framework nanoparticles in Panonychus citri
[0072] The prepared fluorescently labeled iron-based metal organic framework nanoparticle solution was directly sprayed on the surface of the citrus mite, and tissue sections of the citrus mite were prepared to observe the fluorescence.
[0073] 2. Test results:
[0074] The distribution of iron-based metal organic framework nanoparticles in citrus leaves is as follows Figure 4 As shown, the results show that the iron-based metal organic framework nanoparticles prepared by the present invention can effectively penetrate the leaves and have good permeability.
[0075] The distribution of iron-based metal organic framework nanoparticles in Panonychus citri Figure 5 As shown, the results show that the iron-based metal organic framework nanoparticles prepared by the present invention can penetrate the body wall of citrus mite and enter the body of the pest.
[0076] In summary, the iron-based metal organic framework nanoparticles loaded with drugs prepared by the present invention can quickly and effectively enter the target body.
[0077] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.
Claims
1. A nanopesticide preparation for controlling citrus mites, characterized in that: Prepared by the following method: (1) dispersing an iron-based metal-organic framework nanomaterial in a pesticide having acaricidal activity, stirring in the dark, collecting a precipitate by centrifugation, washing, and drying the precipitate to prepare an iron-based metal-organic framework nanomaterial loaded with a pesticide; (2) The iron-based metal organic framework nanomaterial loaded with pesticides is dispersed in deionized water, and a polyethyleneimine aqueous solution is added and stirred to form a polyethyleneimine film on the surface of the iron-based metal organic framework nanomaterial loaded with pesticides. The material is purified by centrifugation and then dispersed in deionized water. Dioctyl sodium sulfosuccinate is added and stirred. Dioctyl sodium sulfosuccinate is adsorbed by charge action to prepare a nanopesticide preparation for controlling citrus mites.
2. The nanopesticide preparation according to claim 1, characterized in that In step (1), the iron-based metal organic framework nanomaterial is prepared by the following method: Ferric chloride hexahydrate is added into deionized water, stirred and dissolved, and then fumaric acid is added to react in a water bath, and a precipitate is collected by centrifugation. The precipitate is washed and dried to prepare an iron-based metal organic framework nanomaterial.
3. The nanopesticide preparation according to claim 2, characterized in that The mass ratio of the added ferric chloride hexahydrate to the fumaric acid is (8-10):
4.
4. The nanopesticide preparation according to claim 2, characterized in that The temperature of the water bath reaction is 50-65°C, and the water bath reaction time is 4-48h.
5. The nanopesticide preparation according to claim 1, characterized in that In step (1), the pesticide having acaricidal activity is matrine and / or spirotetramat.
6. The nanopesticide preparation according to claim 1, characterized in that In step (1), the weight ratio of the pesticide having acaricidal activity to the iron-based metal organic framework nanomaterial is (100-200):(10-20).
7. The nanopesticide preparation according to claim 1, characterized in that In step (2), the weight ratio of the pesticide-loaded iron-based metal organic framework nanomaterial to the polyethyleneimine is (10-20): (0.1-1).
8. The nanopesticide preparation according to claim 1, characterized in that In step (2), the weight ratio of the pesticide-loaded iron-based metal organic framework nanomaterial to dioctyl sodium sulfosuccinate is (10-20):
1.
9. Use of the nanopesticide preparation according to any one of claims 1 to 8 in controlling Panonychus citri.