阅读说明：本技术 一种四元复合纳米控释体系的制备方法 (Preparation method of quaternary composite nano controlled release system ) 是由 周宁琳 王玉丽 沈健 李东辉 楚晓红 孙宝宏 冯文立 石绍泽 徐旺 宋秋娴 于 2020-12-17 设计创作，主要内容包括：本发明公开了一种四元复合纳米控释体系的制备方法,其制备包括：将多巴胺单体加入到石墨烯氧化物水溶液中,反应后离心分离,洗涤得到聚多巴胺/氧化石墨烯水溶液,再取溶于乙醇的啶虫脒加入到聚多巴胺/小尺寸氧化石墨烯水溶液中,搅拌,反应后取其中一部分放入反应釜中制备荧光量子点,后将荧光量子点再加入原体系中形成四元复合纳米农药控释剂。本发明制备工艺简单、操作方便、绿色环保、可控缓释。纳米体系在加入量子点之后显蓝色荧光,用于植物体内可标记追踪；且具有控释功能,可持续高效释放啶虫脒；无有毒的有机溶剂及助剂,绿色安全。(The invention discloses a preparation method of a quaternary composite nano controlled release system, which comprises the following steps: adding a dopamine monomer into a graphene oxide aqueous solution, reacting, performing centrifugal separation, washing to obtain a polydopamine/graphene oxide aqueous solution, adding acetamiprid dissolved in ethanol into the polydopamine/small-size graphene oxide aqueous solution, stirring, reacting, putting a part of the mixture into a reaction kettle to prepare fluorescent quantum dots, and then adding the fluorescent quantum dots into an original system to form the quaternary composite nano pesticide controlled release agent. The preparation method is simple in preparation process, convenient to operate, green, environment-friendly and controllable in slow release. The nano system shows blue fluorescence after the quantum dots are added, and can be used for marking and tracking in a plant body; the acetamiprid release agent has a controlled release function, and can continuously and efficiently release the acetamiprid; no toxic organic solvent and assistant, and is green and safe.)

1. A preparation method of a quaternary composite nano controlled release system is characterized by comprising the following steps:

adding a dopamine monomer into a graphene oxide aqueous solution, adjusting the pH value of the solution, reacting, and washing to obtain a polydopamine/graphene oxide aqueous solution;

dissolving acetamiprid in ethanol, adding the solution into the polydopamine/graphene oxide aqueous solution prepared in the step one, stirring, and centrifuging and washing to obtain an acetamiprid nano controlled-release agent;

step three, adding part of the acetamiprid nanometer controlled release agent prepared in the step two into a reaction kettle, and heating to react to form fluorescent quantum dots;

and step four, mixing the fluorescent quantum dots prepared in the step three with the remaining acetamiprid nano controlled-release agent prepared in the step two to prepare the quaternary composite nano pesticide controlled-release agent.

2. The method for preparing the quaternary composite nano controlled release system according to claim 1, characterized in that: in the first step, dopamine monomer is added into graphene oxide aqueous solution according to equal mass ratio; wherein each 100mL of the aqueous solution contains 500-2000 mg of graphene oxide.

3. The method for preparing the quaternary composite nano controlled release system according to claim 2, characterized in that: the particle size of the graphene oxide is 15-30 nm.

4. The method for preparing the quaternary composite nano controlled release system according to claim 1, characterized in that: in the first step, the pH value of the solution is adjusted to 6-8.

5. The method for preparing the quaternary composite nano controlled release system according to claim 1, characterized in that: in the second step, 5-20 mg of acetamiprid is added into each 100mL of ethanol solution.

6. The method for preparing the quaternary composite nano controlled release system according to claim 1, characterized in that: in the second step, the stirring is performed by using a high-speed homogenizer for rapid stirring under the condition of stirring at the rotating speed of 600-1000 rpm for 10-60 min.

7. The method for preparing the quaternary composite nano controlled release system according to claim 1, characterized in that: in the third step, the acetamiprid nano controlled-release agent used for preparing the fluorescent quantum dots accounts for 20-30% of the total mass of the acetamiprid nano controlled-release agent.

8. The method for preparing the quaternary composite nano controlled release system according to claim 1, characterized in that: in the third step, the reaction temperature is 160-200 ℃, and the reaction time is 6-10 h.

Technical Field

The invention belongs to a preparation method of a plant-protection nano pesticide controlled release agent, and particularly relates to a preparation method of a novel quaternary nano composite pesticide controlled release agent based on a polydopamine/small-size graphene oxide composite material as a controlled release carrier.

Background

As an irreplaceable production data, the pesticide plays an indispensable role in preventing and controlling diseases, pests and weeds of crops, regulating the growth of the crops, guaranteeing the yield and quality of the crops and the like. The prior pesticide preparation field mainly has the problems of simple dosage form structure, few new dosage forms, unstable quality and the like. The pesticide preparation mainly produced still takes the traditional preparations such as missible oil and the like as the main parts, not only has low use efficiency and poor stability, but also poses great threat to the environment. Therefore, the research and development of the pesticide preparation with good water solubility, high stability, long lasting period and environmental friendliness instead of the traditional pesticide preparation with high toxicity, high residue and low stability is an important task in the current pesticide industry.

Starting from changing the original pesticide formulation, the pesticide controlled release technology can be adopted to solve the problems of the traditional pesticide. The drug carrier is an indispensable component in a pesticide controlled release system, and the nano material used as the pesticide carrier comprises a high molecular polymer, a natural high molecular material, an inorganic non-metallic material and the like, wherein the graphene oxide is a novel two-dimensional carbon material with a single-layer sheet structure and is formed by arranging sp of a honeycomb crystal lattice²Hybridized carbon atom. It has a double-sided polycyclic aromatic structure, and the special structure endows the double-sided polycyclic aromatic structure with a very large specific surface area (the theoretical value is 2630 m)²/g) and large delocalized pi-electron systems. The specific surface area is large, and a plurality of action sites can be provided for a target object; the large delocalized pi electron system enables the graphene oxide to have strong pi-pi conjugation effect on the compound with the aromatic ring structure; the graphene oxide structure contains a large amount of hydroxyl and carboxyl, and surface modification is easy. And due to the characteristics of good stability, water solubility and the like, the composite material can be used for loading insoluble pesticides to obtain a pesticide preparation which can be stably dispersed in a water phase. However, the traditional pesticide preparation has low effective utilization rate because the release of the traditional pesticide preparation is not artificially controlled, and the efficiency is reduced because the traditional pesticide preparation has weak interaction with plant leaf surfaces and is easily influenced by factors such as rain wash and the like.

Disclosure of Invention

The purpose of the invention is as follows: the invention aims to provide a preparation method of a quaternary composite nano controlled-release system with high water solubility, high stability and excellent pH controlled-release performance.

The technical scheme is as follows: the invention relates to a preparation method of a quaternary composite nano controlled release system, which comprises the following steps:

adding a dopamine monomer into a graphene oxide aqueous solution, adjusting the pH value of the solution, reacting, and washing to obtain a polydopamine/graphene oxide aqueous solution;

dissolving acetamiprid in ethanol, adding the solution into the polydopamine/graphene oxide aqueous solution prepared in the step one, stirring, and centrifuging and washing to obtain an acetamiprid nano controlled-release agent;

step three, adding part of the acetamiprid nanometer controlled release agent prepared in the step two into a reaction kettle, and heating to react to form fluorescent quantum dots;

and step four, mixing the fluorescent quantum dots prepared in the step three with the remaining acetamiprid nano controlled-release agent prepared in the step two to prepare the quaternary composite nano pesticide controlled-release agent.

Further, in the first step, dopamine monomers are added into the graphene oxide aqueous solution according to an equal mass ratio; wherein, preferably, each 100mL of the aqueous solution contains 500-2000 mg of graphene oxide.

Further, it is characterized in that: the particle size of the graphene oxide is 15-30 nm.

Further, in the first step, the pH value of the solution is adjusted to 6-8; preferably, the pH is about 7.0 to 7.7.

Further, in the second step, 5-20 mg of acetamiprid is added to each 100mL of ethanol solution.

Further, in the second step, the stirring is performed by using a high-speed homogenizer for rapid stirring, and the stirring is performed for 10-60 min at a rotating speed of 600-1000 rpm; preferably, the stirring and mixing are carried out for 30min at the rotation speed of 800 r/min.

Further, in the third step, the acetamiprid nanometer controlled release agent prepared by the fluorescent quantum dots accounts for 20-30% of the total mass of the acetamiprid nanometer controlled release agent.

Further, in the third step, the reaction temperature is 160-200 ℃, and the reaction time is 6-10 hours; preferably, the reaction temperature is 180 ℃ and the reaction time is 8 h.

The reaction principle is as follows: the invention constructs an acetamiprid drug delivery system based on polydopamine modified small-size graphene oxide as a carrier, and forms an environment-friendly acetamiprid nano controlled release agent which has a stable slow release function and remarkably improved insect-resistant activity. The polydopamine is a natural polymeric polymer material, has super-strong adhesion, can remarkably enhance the surface wettability of the material, can effectively improve the effective utilization rate of pesticides by loading the pesticides on the polydopamine modified carrier, prolongs the lasting period of the pesticides, realizes the reduction and the synergism of the pesticides, and the small-size graphene oxide has smaller volume, stronger stability, higher specific surface area and better performance than the graphene oxide; therefore, the polydopamine modified small-size graphene oxide has good wettability, water solubility and an ultra-high specific surface area, and can efficiently load the acetamiprid in a physical adsorption manner, so that the stability and the solubility of the novel acetamiprid nano pesticide controlled release agent in water are effectively improved. The adopted acetamiprid is a chloronicotinyl insecticide, which has the characteristics of wide insecticidal spectrum, high activity, small dosage, long lasting effect, quick acting and the like, has the effects of contact poisoning and stomach toxicity and has excellent systemic activity. It is effective on Hemiptera (aphid, leafhopper, whitefly, scale insect, etc.), Lepidoptera (diamondback moth, leaf miner, budworm, leaf roller), Coleoptera (longicorn, ape leaf worm) and general-winged pests (thrips). In addition, the acetamiprid has unique action mechanism and has good effect on pests with drug resistance to organophosphorus, carbamate, pyrethroid and other pesticide varieties. The method comprises the steps of taking a polydopamine/graphene oxide composite nano material as a pesticide controlled release carrier, using graphene oxide as a raw material, modifying and modifying the polydopamine/small-size graphene oxide nano carrier by using dopamine, loading acetamiprid on the polydopamine/small-size graphene oxide nano carrier by a physical adsorption method, solving the problem that the traditional acetamiprid is poor in water solubility and unstable, preparing the acetamiprid/polydopamine/graphene oxide nano controlled release agent by using the pH controlled release performance and the adhesion performance of polydopamine, and enabling the acetamiprid/polydopamine/graphene oxide nano controlled release agent to have multiple composite functions through controllable pH release so as to form a novel efficient and environment-friendly nano pesticide preparation. The invention also prepares the original acetamiprid nano pesticide controlled release agent into fluorescent quantum dots through high-temperature hydrothermal reaction, and then inserts the fluorescent quantum dots into the original system to form a quaternary composite nano system, and the formed quaternary composite nano system shows blue fluorescence under the irradiation of an ultraviolet lamp, can be used for in-vivo marking and tracking of plants, and can be expanded to the field of biological research. Compared with the common fluorescent quantum dots, the controlled release agent prepared by the self system has the advantage of insect resistance, and the prepared pesticide controlled release agent has the characteristic of fluorescent traceability as a whole, which shows that the acetamiprid nano pesticide controlled release agent and the special fluorescent quantum dots are combined in the system to generate the synergistic effect of insect resistance and tracking and positioning.

Has the advantages that: compared with the prior art, the invention has the following remarkable advantages: the invention prepares a quaternary composite nano controlled release system taking a polydopamine-modified graphene oxide-based composite nano material as a carrier, and the nano controlled release system can effectively improve the water solubility and stability of acetamiprid, endows the acetamiprid with pH controlled release performance, overcomes the characteristic of easy burst release of pesticide, and solves the defect of low target deposition efficiency of the pesticide. In addition, compared with the traditional acetamiprid preparation, the nano controlled release agent does not use toxic organic solvents or auxiliary agents, so that the nano controlled release agent has small harm to the environment, and a quaternary composite nano system formed by the fluorescent quantum dots of the nano controlled release agent can show blue fluorescence and can be marked and tracked in plants, so that the nano controlled release agent is an environment-friendly novel pesticide preparation. The preparation method is simple in preparation process, convenient to operate, green, environment-friendly and controllable in slow release, and blue fluorescence is displayed after the quantum dots are added, so that the fluorescent material can be used for marking and tracking in plants; the acetamiprid release agent has a controlled release function, and can continuously and efficiently release the acetamiprid; the use of the product does not contain toxic organic solvents and auxiliaries, is green and safe, has wide raw material sources, and can be produced and applied on a large scale.

Drawings

FIG. 1 is a transmission electron microscope image of the acetamiprid nano pesticide controlled release agent in example 1 of the present invention;

FIG. 2 is a graph showing the stability test of the acetamiprid-based pesticide release controlling agent in example 1 of the present invention;

FIG. 3 is a UV spectrum of the acetamiprid-based pesticide release controlling agent in example 1 of the present invention;

FIG. 4 is a thermogram of the acetamiprid nano-pesticide controlled-release agent in example 1 of the present invention;

FIG. 5 is a water contact angle test chart of the acetamiprid nano pesticide release controlling agent in example 1 of the present invention;

FIG. 6 is a graph showing the content change of the acetamiprid-based nano pesticide controlled-release agent stored at 0 ℃ and 54 ℃ for 14 days in example 1 of the present invention;

FIG. 7 is a release curve of the acetamiprid nano pesticide controlled-release agent in example 1 of the invention;

FIG. 8 is a pH controlled-release curve of the acetamiprid nano-pesticide controlled-release agent in example 1 of the present invention;

FIG. 9 is a fluorescence image of acetamiprid nano pesticide controlled release agent under an ultraviolet lamp in example 1 of the present invention.

Detailed Description

The technical solution of the present invention will be further described in detail with reference to the accompanying drawings and embodiments.

Example 1

Dissolving 500mg of graphene oxide powder with the average particle size of 15nm in 100mL of distilled water, performing ultrasonic dispersion, then adding 500mg of dopamine monomer, reacting for 30min at room temperature (25 ℃), adding ammonia water to adjust the pH value to 7, stirring for 12h at the speed of 500rmp, then adding 100mL of acetamiprid ethanol solution containing 20mg/mL, stirring for 30min at the high speed of 800rpm by using a high-speed homogenizer, then performing centrifugal washing, and dispersing all solids in 100mL of water to obtain 800mg of 2.0% acetamiprid nano controlled-release agent (m/v, wherein the content of acetamiprid is 20mg/mL), wherein the content of graphene oxide is 0.5% (m/v, g/mL). And then 160mg of acetamiprid nano controlled-release agent is taken into a reaction kettle, the reaction is carried out for 8 hours at the temperature of 180 ℃, the formed fluorescent quantum dots are added into the original acetamiprid nano controlled-release agent and mixed to form the quaternary composite nano pesticide controlled-release agent.

Example 2

The preparation method comprises the steps of dissolving 750mg of graphene oxide powder with the average particle size of 20nm in 100mL of distilled water, performing ultrasonic dispersion, adding 750mg of dopamine monomer, reacting for 30min at room temperature (25 ℃), adding ammonia water to adjust the pH value to 7, stirring for 12h at the speed of 500rmp, adding 100mL of acetamiprid ethanol solution containing 15mg/mL, stirring for 30min at the high speed of 800rpm by using a high-speed homogenizer, performing centrifugal washing, and dispersing all solids in 100mL of water to obtain 1200mg of 1.5% acetamiprid nano controlled-release agent (m/v, wherein the content of acetamiprid is 15mg/mL), wherein the content of graphene oxide is 0.75% (m/v, g/mL). And then 300mg of the acetamiprid nano controlled-release agent is taken into a reaction kettle, the reaction is carried out for 6 hours at the temperature of 160 ℃, and the formed fluorescent quantum dots are added into the original acetamiprid nano controlled-release agent and mixed to form the quaternary composite nano pesticide controlled-release agent.

Example 3

1250mg of graphene oxide powder with the average particle size of 25nm is dissolved in 100mL of distilled water, ultrasonic dispersion is carried out, 1250mg of dopamine monomer is added, after reaction is carried out for 30min at room temperature (25 ℃), ammonia water is added to adjust the pH value to be 7.5, stirring is carried out for 12h at the speed of 500rmp, then 100mL of acetamiprid ethanol solution containing 5mg/mL is added, stirring is carried out for 10min at the high speed of 600rpm by using a high-speed homogenizer, centrifugal washing is carried out, all solids are dispersed in 100mL of water, and 2000mg of 0.5% acetamiprid nano controlled release agent (m/v, wherein the content of acetamiprid is 5mg/mL) is obtained, wherein the content of graphene oxide is 1.25% (m/v, g/mL). And then 400mg of the acetamiprid nano controlled-release agent is taken into a reaction kettle, the reaction is carried out for 10 hours at the temperature of 200 ℃, the formed fluorescent quantum dots are added into the original acetamiprid nano controlled-release agent and mixed to form the quaternary composite nano pesticide controlled-release agent.

Example 4

Dissolving 1000mg of graphene oxide powder with the average particle size of 30nm in 100mL of distilled water, performing ultrasonic dispersion, then adding 1000mg of dopamine monomer, reacting for 30min at room temperature (25 ℃), adding ammonia water to adjust the pH value to 6.5, stirring for 12h at the speed of 500rmp, then adding 100mL of acetamiprid ethanol solution containing 20mg/mL, stirring for 60min at the high speed of 1000rpm by using a high-speed homogenizer, then performing centrifugal washing, and dispersing all solids in 100mL of water to obtain 1600mg of 2.0% acetamiprid nano controlled release agent (m/v, wherein the content of acetamiprid is 20mg/mL), wherein the content of graphene oxide is 1.0% (m/v, g/mL). 480mg of acetamiprid nano controlled-release agent is added into a reaction kettle and reacts for 8 hours at 180 ℃, and the formed fluorescent quantum dots are added into the original acetamiprid nano controlled-release agent and mixed to form the quaternary composite nano pesticide controlled-release agent.

Example 5

Dissolving 1500mg of graphene oxide powder with the average particle size of 20nm in 100mL of distilled water, performing ultrasonic dispersion, then adding 1500mg of dopamine monomer, reacting for 30min at room temperature (25 ℃), adding ammonia water to adjust the pH value to 6.0, stirring for 12h at the speed of 500rmp, then adding 100mL of acetamiprid ethanol solution containing 20mg/mL, stirring for 30min at the high speed of 800rpm by using a high-speed homogenizer, then performing centrifugal washing, and dispersing all solids in 100mL of water to obtain 2400mg of 2.0% acetamiprid nano controlled release agent (m/v, wherein the content of acetamiprid is 20mg/mL), wherein the content of graphene oxide is 1.5% (m/v, g/mL). And adding 700mg of acetamiprid nano controlled-release agent into a reaction kettle, reacting for 8 hours at 180 ℃, adding the formed fluorescent quantum dots into the original acetamiprid nano controlled-release agent, and mixing to form the quaternary composite nano pesticide controlled-release agent.

Example 6

Dissolving 2000mg of graphene oxide powder with the average particle size of 25nm in 100mL of distilled water, performing ultrasonic dispersion, then adding 2000mg of dopamine monomer, reacting for 30min at room temperature (25 ℃), adding ammonia water to adjust the pH value to 8.0, stirring for 12h at the speed of 500rmp, then adding 100mL of acetamiprid ethanol solution containing 15mg/mL, stirring for 30min at the high speed of 800rpm by using a high-speed homogenizer, then performing centrifugal washing, and dispersing all solids in 100mL of water to obtain 3200mg of 1.5% acetamiprid nano controlled release agent (m/v, wherein the content of acetamiprid is 15mg/mL), wherein the content of graphene oxide is 2.0% (m/v, g/mL). 650mg of acetamiprid nano controlled-release agent is added into a reaction kettle and reacts for 8 hours at 180 ℃, and the formed fluorescent quantum dots are added into the original acetamiprid nano controlled-release agent and mixed to form the quaternary composite nano pesticide controlled-release agent.

And (3) determining the morphology: a certain amount of the acetamiprid nano pesticide controlled release agent prepared in the example 1 is diluted and dropped on a silicon wafer to prepare a sample, and the appearance of the sample is observed by using a scanning electron microscope. As shown in FIG. 1, a large number of particles with the size of about 800-1000nm appear on the surface of the small-sized graphene oxide, and the particles are acetamiprid particles. The nano size greatly improves the solubility of the acetamiprid, the small-size graphene oxide has good water solubility, and the acetamiprid loaded on the surface of the small-size graphene oxide can be dissolved in water along with the small-size graphene oxide lamella and uniformly dispersed, so that the solubility of the acetamiprid is greatly improved.

And (3) stability testing: as shown in FIG. 2, 7mL of the acetamiprid-based pesticide controlled-release agent prepared in example 1 was placed in a 10mL graduated cylinder, and the existence of precipitation or delamination was observed after standing at room temperature for 48 hours. After standing for 48 hours, no obvious layering and no precipitate are generated, which indicates that the stability is good.

Testing by an ultraviolet spectrophotometer: as shown in fig. 3, 2mL of the acetamiprid-based nano-pesticide controlled-release agent prepared in example 1 was placed in a semi-permeable cuvette, and an ultraviolet characteristic absorption peak of the acetamiprid was measured by an ultraviolet spectrophotometer, and the ultraviolet absorption characteristic peak of the acetamiprid appeared in the acetamiprid/polydopamine/graphene oxide composite material, which indicates the successful synthesis of the prepared acetamiprid-based nano-pesticide controlled-release agent.

Thermal stability and drug loading analysis: as shown in fig. 4, the acetamiprid/polydopamine/graphene oxide composite material prepared in example 1 is subjected to thermal decomposition in a thermal analyzer under a nitrogen atmosphere at room temperature to 800 ℃, and the final loss amount of the acetamiprid/polydopamine/graphene oxide composite material after thermal decomposition is 60.1%, while the final loss amount of the polydopamine small graphene oxide nano-carrier is 47.9%, so that the load amount of the acetamiprid can be calculated to be 12.2%, and it can be found that the acetamiprid/polydopamine/small-size graphene oxide composite nano-material after drug loading is decomposed after 200 ℃, and the acetamiprid/polydopamine/small-size graphene oxide composite nano-material has good thermal stability.

And (3) testing the wettability of the material: in order to evaluate the wetting characteristics of the polydopamine/graphene oxide carrier and the acetamiprid loaded in the polydopamine/graphene oxide (i.e., the acetamiprid nano-pesticide controlled-release agent prepared in example 1 of the present invention), static contact angle measurements were performed on corn leaves, and the results are shown in fig. 5. As a control, the contact angle of pure water on the corn leaf in a is 96.3 +/-0.1 degrees, and the value higher than 90 degrees indicates that the surface of the corn leaf has hydrophobicity. The contact angle of the 20mg/mL acetamiprid solution in ethanol on the leaves in b is about 73.7 + -2.3 deg., which shows that the acetamiprid dissolved in ethanol can wet the corn leaves, which can be interpreted as: ethanol as an organic solvent can wet hydrophobic surfaces. In the step c, an aqueous solution of 20mg/mL polydopamine/small-size graphene oxide (in example 1, no acetamiprid ethanol solution is added, and the prepared polydopamine/small-size graphene oxide is dispersed in water to prepare an aqueous solution of 20mg/mL polydopamine/small-size graphene oxide) can wet cucumber leaves to a certain extent, wherein the contact angle on the leaves is 72.3 +/-10 degrees, and the wettability of the cucumber leaves is improved compared with that of water. In the step d, the contact angle between the acetamiprid nano pesticide controlled-release agent (20 mg/mL) and the corn leaf blade is reduced to 65.2 +/-0.01 degrees according to the method in the example 1, and the value shows that the acetamiprid/polydopamine/small-size graphene oxide composite material has good wettability on the corn leaf blade.

High temperature storage stability test: the acetamiprid nano pesticide controlled release agent prepared in the example 1 is stored for 14 days at 54 ℃, whether precipitation or delamination occurs is observed, and the content of the acetamiprid nano pesticide controlled release agent is measured. As shown in FIG. 5, no precipitate was generated and no delamination occurred after high temperature storage, wherein the acetamiprid content was determined to be 2.0. + -. 0.02% and showed no significant decrease.

Low-temperature storage stability test: the acetamiprid nano pesticide controlled release agent prepared in the example 1 is stored for 7 days at 0 ℃, whether precipitation or delamination occurs is observed, and the content of the acetamiprid nano pesticide controlled release agent is measured. As shown in FIG. 6, no precipitation occurred and no delamination occurred after low temperature storage, wherein the acetamiprid content was determined to be 2.0. + -. 0.01%, and no significant decrease was exhibited.

Stability testing under different water quality conditions: 20mg/L acetamiprid nano pesticide controlled release agent is prepared according to the method of the example 1, and is diluted by 20 times by pure water, standard hard water and tap water respectively, and the stability condition is observed. The acetamiprid nano pesticide controlled release agent shows a stable dispersion state in various water samples.

And (3) slow release determination: 10mL of the acetamiprid nano pesticide controlled-release agent prepared in the example 1 is placed in a dialysis bag (8000-. As shown in figure 7, the acetamiprid nano pesticide controlled release agent has good slow release performance, is slowly released by about 50% within 72 hours, and shows a sustained release trend.

And (3) pH controlled release performance determination: 10mL of the acetamiprid nano pesticide controlled-release agent prepared in example 1 was placed in a dialysis bag (8000- "14000 Da"), and then dialyzed in 2L of distilled water dialysate containing 30% ethanol (pH was adjusted to 5, 6, 7, and 8 with NaOH solution, and was measured with a pH meter), and the acetamiprid concentration in the dialysate was measured by sampling 12 points per day on days 0-20 to obtain the acetamiprid sustained-release curve. As shown in fig. 8, it is demonstrated that the acetamiprid-based pesticide controlled-release agent has good pH controlled-release performance, the release amount is the highest at pH 7, the release amount is less than 60% within 20 days, and the sustained-release trend is shown, which indicates that the acetamiprid-based pesticide controlled-release agent has pH controllable performance.

Measurement of fluorescence properties: fig. 9 shows that the acetamiprid-based nano-pesticide controlled-release system prepared in example 1 is irradiated with fluorescent quantum dots in a closed ultraviolet lamp dark box, and it can be seen from the graph that under an ultraviolet lamp (365nm), weak blue fluorescence appears, while the acetamiprid-based nano-pesticide controlled-release agent original system does not have fluorescence, and the quantum dots with blue fluorescence are added into the acetamiprid-based nano-pesticide controlled-release system to form a new quaternary polymerization nano-system, which has a fluorescence labeling function and can be tracked in plants.