A indoxacarb-loaded granule

Abstract

The present invention discloses a indoxacarb-loaded granule, which relates to the field of pesticide loading and application. The characteristics of an indoxacarb-loaded granule include: (1) preparing a metal-organic framework (MIL-100(Fe)) as a carrier material; (2) loading the pesticide indoxacarb onto the carrier material to obtain a sample loaded with the pesticide indoxacarb; (3) coating chitosan onto the sample loaded with the pesticide indoxacarb and chelating copper ions. The indoxacarb-loaded granule slowly releases indoxacarb in the area where pests occur or may occur, and the release rate is regulated by pH value and temperature, which can improve the control effect on pests and reduce the toxicity to natural enemies.

Description

Technical Field

[0001] The present invention relates to the field of pesticide loading and application, and particularly to a indoxacarb-loaded granule. Background Art

[0002] As an important material in agricultural production, chemical pesticides play an important role in controlling diseases, insects and weeds and ensuring the safe production of food. Indoxacarb (IN for short) is a broad-spectrum oxadiazine insecticide. By blocking the sodium ion channels in insect nerve cells, it makes the nerve cells lose their functions. It has contact and stomach toxicity effects and can effectively control various pests on crops such as grains, cotton, fruits and vegetables. However, at present, due to the short pesticide persistence period and unreasonable use, the actual field application amount of pesticides far exceeds the environmental tolerance, resulting in waste of resources and serious environmental pollution. At the same time, it also kills a large number of natural enemies of pests and accelerates the occurrence of pest resistance.

[0003] Metal-organic frameworks (MOFs) are crystalline porous materials with a periodic infinite network framework structure constructed with metal ions / clusters as nodes and one or more organic compounds as ligands. They have characteristics such as large specific surface area, adjustable pore size and diverse structures, and have attracted much attention in the fields of physics, chemistry, biomedicine, etc. Loading target pesticides with metal-organic frameworks as carriers can control drug release and effectively extend the persistence period. Chitosan is a product obtained by removing part of the acetyl groups from natural polysaccharide chitin. It has characteristics such as biodegradability, biocompatibility, non-toxicity and antibacterial properties, and is widely used in the field of drug sustained-release materials. At the same time, the abundant amino and hydroxyl groups in the chitosan molecule have strong adsorption and coordination effects. After coating chitosan on the drug-loaded metal-organic framework and then coordinating and chelating with copper ions, the respective advantages of the three can be fully exerted. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide an indoxacarb-loaded granule and its use.

[0005] The indoxacarb-loaded granule provided by the present invention can continuously and slowly release indoxacarb, and the release rate is regulated by pH value and temperature, effectively extending the persistence period of indoxacarb; it is used to highly efficiently kill the pest Helicoverpa armigera, and can greatly reduce the toxicity of indoxacarb to the natural enemy Chrysopa septempunctata.

[0006] To achieve the above purpose, the present invention proposes the following technical solutions:

[0007] A indoxacarb-loaded granule is characterized by including:

[0008] (1) Preparing a metal-organic framework material as a carrier material;

[0009] (2) Load indoxacarb pesticide on a metal-organic framework material to obtain a sample loaded with indoxacarb pesticide;

[0010] (3) Coat chitosan on the sample loaded with indoxacarb pesticide and chelate copper ions.

[0011] For the above preparation method of indoxacarb-loaded drug particles, in step (1), the following steps are included:

[0012] (1-1) Ultrasonically disperse iron powder, trimesic acid, hydrofluoric acid, and nitric acid into ultrapure water; the molar ratio of iron powder, trimesic acid, hydrofluoric acid, nitric acid, and water is 1.0 / 0.67 / 2.0 / 0.6 / 277;

[0013] (1-2) Transfer the mixed solution obtained in step (1-1) to a reaction kettle, seal it, heat it to 150 °C, and maintain it for 12 h;

[0014] (1-3) Filter the mixed solution obtained in step (1-2), wash the obtained solid with ultrapure water, and redisperse it in water / ethanol for reflux to remove unreacted raw materials; the obtained solid is washed 3 times with pure water, first dispersed in pure water, heated to 100 °C, and refluxed for 5 h; after the reaction, the product is centrifuged and redispersed in ethanol, heated to 70 °C, and refluxed for 3 h;

[0015] (1-4) Centrifuge the mixed solution obtained in step (1-3), and vacuum-dry the obtained solid at 80 °C overnight to obtain the MIL-100(Fe) carrier material.

[0016] For the above preparation method of indoxacarb-loaded drug particles, in step (2), the following steps are included:

[0017] (2-1) Add indoxacarb technical and MIL-100(Fe) material to 10 mL of dichloromethane, and stir magnetically at room temperature; the mass ratio of indoxacarb technical and MIL-100(Fe) material is 1:1, and the stirring time is 10 h;

[0018] (2-2) Centrifuge the mixed solution obtained in step (2-1), and rinse the lower-layer solid with pure water; the centrifugation speed is 10000 rpm, the time is 10 min, and it is rinsed 3 times with pure water;

[0019] (2-3) Dry the solid obtained in step (2-2) to obtain the sample loaded with indoxacarb (IN@MIL-100(Fe)), where the drying temperature is 60 °C.

[0020] For the above preparation method of indoxacarb-loaded drug particles, in step (3), the following steps are included:

[0021] (3-1) Disperse the sample loaded with indoxacarb obtained in step (2) into a phosphate buffer solution; the concentration of the phosphate buffer solution is 0.05 M and the pH value is 6;

[0022] (3-2) Drop the chitosan solution into the mixed solution obtained in (3-1), and stir magnetically at room temperature; the mass concentration of the chitosan solution is 2%, and the stirring time is 5 h;

[0023] (3-3) Centrifuge the mixed solution obtained in step (3-2), and rinse the lower-layer solid with a phosphate buffer solution. The centrifugation speed is 10000 rpm, the time is 10 min, and the phosphate buffer solution is rinsed 3 times;

[0024] (3-4) Redisperse the solid product obtained in step (3-3) into a copper sulfate solution, and stir magnetically at room temperature; the concentration of the copper sulfate solution is 0.5 M, and the stirring time is 3 h;

[0025] (3-5) Centrifuge the mixed solution obtained in step (3-4), and rinse the lower-layer solid with pure water; the centrifugation speed is 10000 rpm, the time is 10 min, and the pure water is rinsed 3 times;

[0026] (3-6) Dry the solid product obtained in step (3-5) under vacuum conditions to obtain indoxacarb-loaded particles (Cu-CS@IN@MIL-100(Fe)).

[0027] For the indoxacarb-loaded particles described above, the release rate of indoxacarb is regulated by the pH value and temperature.

[0028] The beneficial effects of the present invention are as follows:

[0029] In order to extend the effective period of indoxacarb, improve the control effect on the pest Helicoverpa armigera, and at the same time reduce the toxicity to Chrysopa septempunctata. In the present invention, indoxacarb is loaded with a metal-organic framework as a carrier, and after loading the drug, the drug-loading system is further coated with chitosan and chelated with copper ions. The final obtained drug-loaded particles have a drug-loading rate as high as 36.25%. The drug-loaded particles provided by the present invention have good controlled-release performance and can be slowly released at different pH values and different temperatures, effectively extending the effective period of indoxacarb; the drug-loaded particles provided by the present invention have good biological activity, and at the same time can effectively reduce the toxicity to the natural enemy Chrysopa septempunctata; and the drug-loaded particles provided by the present invention have good safety for plants and can also promote the germination of cotton seeds. Description of the Drawings

[0030] Figure 1 It is the thermogravimetric analysis curves of the drug-loaded particles (Cu-CS@IN@MIL-100(Fe)), the carrier material (MIL-100(Fe)), the indoxacarb technical (IN) and chitosan (CS);

[0031] Figure 2 Scanning electron microscope images of the carrier material (A) and the drug-loaded particles (B);

[0032] Figure 3 Infrared spectra of the carrier material, the drug-loaded particles, and the indoxacarb technical;

[0033] Figure 4 Nitrogen adsorption-desorption isotherms of the carrier material and the drug-loaded particles;

[0034] Figure 5 Pore size distribution curves of the carrier material and the drug-loaded particles;

[0035] Figure 6 X-ray photoelectron spectroscopy (XPS) of the carrier material and the drug-loaded particles;

[0036] Figure 7 X-ray diffraction (XRD) of the carrier material and the drug-loaded particles;

[0037] Figure 8 Release curves of the drug-loaded particles under different pH values (A) and different temperatures (B);

[0038] Figure 9 Bioactivity determination results of the drug-loaded particles and 15% indoxacarb suspension;

[0039] Figure 10 Toxicity determination results of the drug-loaded particles and 15% indoxacarb suspension against Chrysopa septempunctata. Detailed implementation manners

[0040] To more clearly illustrate the solutions in the present invention, the present invention will be further described below in conjunction with preferred embodiments and the accompanying drawings. The specific content described below is illustrative rather than restrictive, and should not be used to limit the protection scope of the present invention.

[0041] Characteristics of an indoxacarb-loaded particle, including:

[0042] (1) Preparing a metal-organic framework material as the carrier material;

[0043] (1-1) Ultrasonically dispersing iron powder, trimesic acid, hydrofluoric acid, and nitric acid into ultrapure water; wherein the molar ratio of iron powder, trimesic acid, hydrofluoric acid, nitric acid, and water is 1.0 / 0.67 / 2.0 / 0.6 / 277;

[0044] (1-2) Transferring the mixed solution obtained in step (1-1) to a reaction kettle, sealing and heating it to 150 °C and maintaining for 12 h;

[0045] (1-3) Filter the mixed solution obtained in step (1-2). Wash the obtained solid with ultrapure water and redisperse it in water / ethanol, then reflux to remove unreacted raw materials. The obtained solid is washed with pure water three times. First, disperse it in pure water, heat to 100 °C and reflux for 5 h. After the reaction, centrifuge the product and redisperse it in ethanol, heat to 70 °C and reflux for 3 h.

[0046] (1-4) Centrifuge the mixed solution obtained in step (1-3). Vacuum-dry the obtained solid at 80 °C overnight to obtain the MIL-100(Fe) support material.

[0047] (2) Load the pesticide indoxacarb onto the metal-organic framework material to obtain a sample of indoxacarb-loaded metal-organic framework material.

[0048] (2-1) Add indoxacarb technical and MIL-100(Fe) material to 10 mL of dichloromethane and stir magnetically at room temperature. The mass ratio of indoxacarb technical to MIL-100(Fe) material is 1:1, and the stirring time is 10 h.

[0049] (2-2) Centrifuge the mixed solution obtained in step (2-1) and rinse the lower-layer solid with pure water. The centrifugation speed is 10000 rpm, the time is 10 min, and it is rinsed with pure water three times.

[0050] (2-3) Dry the solid obtained in step (2-2) to obtain the indoxacarb-loaded sample (IN@MIL-100(Fe)), where the drying temperature is 60 °C.

[0051] Coating chitosan onto the indoxacarb-loaded sample while chelating copper ions.

[0052] (3-1) Disperse the indoxacarb-loaded sample in a phosphate buffer solution. The concentration of the phosphate buffer solution is 0.05 M and the pH value is 6.

[0053] (3-2) Drop the chitosan solution into the mixed solution obtained in (3-1) and stir magnetically at room temperature. The mass concentration of the chitosan solution is 2%, and the stirring time is 5 h.

[0054] (3-3) Centrifuge the mixed solution obtained in step (3-2) and rinse the lower-layer solid with the phosphate buffer solution. The centrifugation speed is 10000 rpm, the time is 10 min, and it is rinsed with the phosphate buffer solution three times.

[0055] (3-4) Redisperse the solid product obtained in step (3-3) in a copper sulfate solution and stir magnetically at room temperature. The concentration of the copper sulfate solution is 0.5 M, and the stirring time is 3 h.

[0056] (3 - 5) Centrifuge the mixed solution obtained in step (3 - 4), and rinse the lower - layer solid with pure water; the centrifuge speed is 10000 rpm, the time is 10 min, and rinse with pure water 3 times;

[0057] (3 - 6) Dry the solid product obtained in step (3 - 5) under vacuum conditions to obtain the drug - loaded particles (Cu - CS@IN@MIL - 100(Fe)).

[0058] The drug - loaded particles (Cu - CS@IN@MIL - 100(Fe)) prepared by the preparation method of this example can be used to control Helicoverpa armigera.

[0059] In this example, the properties of the prepared carrier material and drug - loaded particles were characterized, and the bioactivity of the drug - loaded particles and the safety test on Chrysopa pallens were carried out. The test contents are as follows:

[0060] (1) Drug - loading rate determination experiment

[0061] Weigh the drug - loaded particles into a 25 - mL volumetric flask, add a mixed solution of acetonitrile, water, and acetic acid (acetonitrile: water: acetic acid = 20:4.95:0.05), and perform ultrasonic elution of the indoxacarb pesticide loaded on it. After ultrasonic treatment for 2 h, make up the volume with the mixed solution and mix well. Use a syringe to draw 1 mL of the made - up solution, filter it through a 0.45 - μm organic filter membrane, and then detect the content of indoxacarb in the eluate by high - performance liquid chromatography. Calculate the drug - loading rate of the drug - loaded particles according to the formula.

[0062]

[0063] Among them, the experimental results show that the drug - loading rate of the drug - loaded particles is 36.05% ± 2.09.

[0064] (2) Scanning electron microscope analysis (SEM)

[0065] The carrier material and drug - loaded particles prepared in the example were analyzed by scanning electron microscopy. The results are as Figure 2 shown, Figure 2 In Figure A in the figure is the prepared carrier material. It can be seen that the carrier material is an octahedral structure with a smooth surface; Figure B is the sample of chitosan - coated metal - organic framework loaded with indoxacarb and chelating copper ions. It can be seen that the sample is still an octahedral structure, but the surface is relatively rough, indicating that the framework structure of the carrier material does not change after loading the drug and coating with chitosan, but the surface is successfully coated with chitosan.

[0066] (3) Thermogravimetric analysis (TGA)

[0067] Due to the different thermal decomposition properties of different substances, a thermogravimetric analyzer was used to conduct thermogravimetric analysis experiments on the carrier material, drug - loaded particles, chitosan, and indoxacarb technical. The results are as Figure 1As shown in the figure. Due to the adsorption of water molecules by the material, the weight losses of the carrier material, drug-loaded particles, chitosan, and indoxacarb technical in the range of 0 to 100 °C are 21.2%, 3.77%, and 8.13% respectively, while the weight of indoxacarb technical hardly changes; the weight loss of indoxacarb technical mainly occurs at 250 to 360 °C. In this temperature range, chitosan also has a relatively large weight loss. At the same time, it is observed that the weight loss rate of the drug-loaded particles in this temperature range is significantly faster than that of the carrier material, indicating that indoxacarb is successfully loaded onto the carrier material and coated with chitosan; in the range of 100 to 800 °C, the weight losses of the carrier material and the drug-loaded particles are 49.56% and 62.90% respectively. In this temperature range, the weight loss of the drug-loaded particles is 13.34% more than that of the carrier material, which also shows that indoxacarb and chitosan are successfully coated onto the carrier material.

[0068] (4) Fourier Transform Infrared Spectroscopy (FT-IR)

[0069] Fourier transform infrared spectroscopy tests were carried out on indoxacarb technical, carrier material, and drug-loaded particles, and the results are as Figure 3 shown. Characteristic absorption peaks of indoxacarb technical appear at 762.01, 1247.01, 1694.88, 1742.84, and 2959.60 cm -1 . Among them, the peak at 762.01 cm -1 is the stretching vibration peak of C-Cl; the peak at 1247.01 cm -1 is the asymmetric stretching vibration of C-O-C; the peaks at 1694.88 and 1742.84 cm -1 are the stretching vibration peaks of -C=O; the peak at 2959.60 cm -1 is the stretching vibration peak of C-H. Characteristic absorption peaks of the carrier material appear at 1626.81, 1445.04, 1376.96, 757.37, 712.50, and 626.64 cm -1 . Among them, the peak at 1626.81 cm -1 is the stretching vibration peak of C–O on the carboxyl group; the sharp peaks at 1445.04 and 1376.96 cm -1 belong to the asymmetric and symmetric vibrations of the O-C-O group; the peaks at 757.37 and 712.50 cm -1 belong to the bending vibration of C-H on the benzene ring; the peak at 626.64 cm -1 is the Fe-oxo bond formed between the carboxyl group and Fe(III) ions. The characteristic absorption peaks of indoxacarb technical appear in the drug-loaded particles, indicating that indoxacarb is successfully loaded onto the carrier material.

[0070] (5) Specific Surface Area and Pore Size Distribution Characterization

[0071] Specific surface area and pore size distribution tests were carried out on the carrier material and the drug-loaded particles. The results are asFigure 4 , Figure 5 As shown in Figure 5 and Table 1, the specific surface areas of the carrier material and the drug-loaded particles calculated according to the Brunauer-Emmett-Teller (BET) method are 1433.704 and 1.690 m 2 / g, respectively, and the pore volumes are 0.743 and 0.002 cm 3 / g, respectively. After loading the drug, the specific surface area and pore volume of the carrier material decreased significantly because indoxacarb and chitosan occupied the pores of the carrier material, indicating that indoxacarb and chitosan were successfully loaded onto the carrier material.

[0072] Table 1 Specific surface area and pore volume of the carrier material and the drug-loaded particles

[0073] Sample <![CDATA[S BET (m 2 / g)]]> <![CDATA[V t (cm 3 / g)]]> Carrier material 1433.704 0.743 Drug-loaded particle 1.690 0.002

[0074] (6) X-ray photoelectron spectroscopy (XPS) analysis

[0075] X-ray photoelectron spectroscopy (XPS) analysis was performed on the carrier material and the drug-loaded particles. The results are as Figure 6 shown. The typical peaks of Fe 2p (711.75 eV), O 1s (531.67 eV), C 1s (284.75 eV), N 1s (400.24 eV) and F 1s (688.8 eV) are present in both the carrier material and the drug-loaded particles. Compared with the carrier material, a new peak attributed to Cu 2p appears at 934.24 eV in the drug-loaded particles, and the relative content of F 1s increases significantly, indicating that indoxacarb was successfully loaded and chitosan was successfully coated while chelating copper ions.

[0076] (7) X-ray diffraction (XRD) analysis

[0077] X-ray diffraction (XRD) analysis was performed on the carrier material and the drug-loaded particles, and the results are as Figure 7 shown. The diffraction peaks (2θ) of the prepared carrier material and the drug-loaded particles are consistent with the simulated diffraction peaks of the carrier material, indicating that the carrier material was successfully prepared and the crystal structure of the carrier material did not change after loading the drug.

[0078] (8) Release performance test of the drug-loaded particles

[0079] Plant leaves are the main parts damaged by pests, and pesticides are usually absorbed by plant leaves to play their roles. According to the pH value of cotton sap (pH = 5.84), three different pH release media of 4.92, 7.17 and 9.90 were selected to study the pH-sensitive release curve of IN in the drug-loaded particles, and the results are as Figure 8As shown in A, the release rate of IN in the drug-loaded particles is faster under weakly acidic conditions. In the initial release, the three release curves are similar. At 50 h, the cumulative release amounts of IN at pH 4.92, 7.17, and 9.90 are 50%, 49%, and 42%, respectively. However, at 228 h, the cumulative release amounts under acidic (pH 4.92) and neutral (pH 7.17) conditions are 92% and 82%, respectively, while only about 50% under the alkaline condition of pH 9.90. The faster release rate of the drug-loaded particles prepared in this example under acidic conditions may be due to the protonation of the chitosan layer on the surface of the drug-loaded particles in the acidic solution, thus opening the blocked mesoporous channels. The results show that the drug-loaded particles can be continuously and slowly released after being absorbed by cotton leaves.

[0080] In addition, we also studied the release performance of the drug-loaded particles at different temperatures (25 °C, 35 °C). The results are as Figure 8 shown in B. At 0 - 100 h, the cumulative release amount of the drug-loaded particles under the condition of 35 °C is as high as 80%, while that under the condition of 25 °C is only 62%. The release at 25 °C lasted for 130 h to reach the highest point, while at 35 °C, the release process lasted for up to 260 h. Combining the release rate and release time indicates that the release of indoxacarb in the drug-loaded particles is regulated by temperature. The lower the temperature, the slower the release rate and the longer the continuous release time.

[0081] (9) Insecticidal activity test

[0082] Weigh the drug-loaded particles and 15% indoxacarb suspension concentrate, and prepare the stock solution with acetone. The leaf-dipping method was used to determine the biological activity of Helicoverpa armigera. The tested Helicoverpa armigera were second-instar larvae continuously reared indoors at the Cotton Research Institute, Chinese Academy of Agricultural Sciences with consistent physiological states. The stock solution was serially diluted to 100, 50, 25, 12.5, 6.25, 3.125 mg / L. The picked cotton leaves were immersed in the test drug solution, taken out and dried after 10 s, and then 10 tested Helicoverpa armigera were introduced. Each treatment was repeated 5 times, and a treatment without the drug was set as the blank control. The treated test insects were reared and observed under the conditions of temperature (28 ± 2) °C, humidity 35 ± 5%, and photoperiod L:D = (14:10) h. The death situation of the test insects was checked 48 h after treatment, and the total number of insects and the number of dead insects were recorded respectively. The probit analysis method was used to process the data, and the toxicity regression equation LC 50 and its 95% confidence limit were obtained to evaluate the activities of the drug-loaded particles and indoxacarb technical against Helicoverpa armigera. The results are shown in Table 2 and Figure 9 as follows.

[0083] Table 2 Toxicity of the drug-loaded particles and 15% indoxacarb suspension concentrate against Helicoverpa armigera

[0084] Sample <![CDATA[LC 50 (95%CI)(a.i.,mg / L)]]> Slope±SE <![CDATA[X 2 (df)]]> 15% Chlorantraniliprole Suspension Concentrate 10.213(4.505-18.663) 2.902±0.342 12.444(4) Drug-loaded particle 4.936(3.928-5.947) 4.369±0.579 4.010(4)

[0085] (10)Safety determination of Chrysopa pallens

[0086] The safety of predatory natural enemies was determined by the spray tower method. Weigh the drug-loaded particles and 15% indoxacarb suspension, and prepare the mother liquor with acetone. Gradient dilute the mother liquor to 280, 210, 140, 105, 70, 52.5, 35 mg / L. The test Chrysopa pallens were second-instar larvae that were continuously reared indoors with Acyrthosiphon pisum by the Institute of Cotton Research, Chinese Academy of Agricultural Sciences and had consistent physiological states. Before spraying, take the second-instar larvae into a 9-cm culture dish and anesthetize them with carbon dioxide. After anesthesia (about 2 min), take them out, suck 2 mL of the test agent with a pipette and spray it in the spray tower. After about 10 s, wait for the liquid medicine to completely settle, take out the culture dish, treat 10 insects per dish, and repeat 6 times. The blank control only sprays clear water. After the medicine dries, transfer the test insects to a new culture dish and add a sufficient amount of Acyrthosiphon pisum, and place them under the conditions of temperature (26±2)°C, humidity 55±5%, and photoperiod L:D=(14:10)h for feeding and observation. Check the death of the test insects 72 h after treatment, and record the total number of insects and the number of dead insects respectively. Use the probit analysis method to process the data and obtain the toxicity regression equation LC 50 and its 95% confidence limit, and evaluate the toxicity of the drug-loaded particles and 15% indoxacarb suspension to Chrysopa pallens. The results are shown in Table 3 and Figure 10 as follows.

[0087] Table 3 Toxicity of drug-loaded particles and 15% indoxacarb suspension to Chrysopa pallens

[0088] Sample <![CDATA[LC 50 (95%CI)(a.i.,mg / L)]]> Slope±SE <![CDATA[X 2 (df)]]> 15% Chlorantraniliprole Suspension Concentrate 55.388(44.723-65.677) 8.024±0.836 11.552(5) Drug-loaded particle 174.556(157.441-196.316) 5.814±0.574 2.944(5)

[0089] The above is only the preferred implementation mode of the present invention. It should be pointed out that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and retouches can be made, and these improvements and retouches should also be regarded as the protection scope of the present invention.

Claims

1. An indoxacarb-loaded drug particle, characterized in that, it comprises: (1) Prepare a metal-organic framework material as a carrier material; (2) Load the pesticide indoxacarb on the metal-organic framework material to obtain a loaded pesticide indoxacarb sample; (3) Coating chitosan on the loaded pesticide indoxacarb sample and chelating copper ions to obtain indoxacarb-loaded drug particles; wherein, the metal-organic framework material in step (1) and step (2) is MIL-100(Fe).

2. The indoxacarb-loaded drug particle according to claim 1, characterized in that, the preparation method of the metal-organic framework material comprises: (1-1) Ultrasonically disperse iron powder, trimesic acid, hydrofluoric acid and nitric acid into ultrapure water; (1-2) Transfer the mixed solution obtained in step (1-1) to a reaction kettle, seal it and heat it; (1-3) Filter the mixed solution obtained in step (1-2), wash the obtained solid with ultrapure water, and redisperse it in water / ethanol to reflux to remove unreacted raw materials; (1-4) Centrifuge and vacuum dry the mixed solution obtained in step (1-3) to obtain the MIL-100(Fe) carrier material.

3. The indoxacarb-loaded drug particle according to claim 1, characterized in that, the preparation method of the loaded pesticide indoxacarb sample comprises: (2-1) Add indoxacarb technical and MIL-100(Fe) material to dichloromethane, and stir magnetically at room temperature; (2-2) Centrifuge the mixed solution obtained in step (2-1), and rinse the lower-layer solid with pure water; (2-3) Dry the solid obtained in step (2-2) to obtain the loaded indoxacarb sample IN@MIL-100(Fe).

4. The indoxacarb-loaded drug particle according to claim 1, characterized in that, the preparation method of coating chitosan on the loaded pesticide indoxacarb sample and chelating copper ions comprises: (3-1) Disperse the loaded indoxacarb sample into a phosphate buffer solution; (3-2) Drop the chitosan solution into the mixed solution obtained in (3-1), and stir magnetically at room temperature; (3-3) Centrifuge the mixed solution obtained in step (3-2), and rinse the lower-layer solid with a phosphate buffer solution; (3-4) Redisperse the solid product obtained in step (3-3) into a copper sulfate solution, and stir magnetically at room temperature; (3-5) Centrifuge the mixed solution obtained in step (3-4), and rinse the lower-layer solid with pure water; (3-6) Dry the solid product obtained in step (3-5) under vacuum conditions to obtain the drug-loaded particles Cu-CS@IN@MIL-100(Fe).

5. The indoxacarb-loaded drug particle according to claim 1, characterized in that, the release rate of the indoxacarb-loaded drug particle to release indoxacarb is regulated by pH value and temperature.

6. The use of an indoxacarb-loaded drug particle, characterized in that, the drug-loaded particles described in any one of claims 1-4 can improve the control effect on pests and can reduce the toxicity to natural enemies.

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