Preparation method of cyhalofop-butyl-containing dispersible oil suspending agent
By combining azobenzene-mesoporous silica composite carrier and molecularly imprinted polymer, a cyhalofop-butyl dispersible oil suspension was designed, which realizes rapid release and sustained release of the drug on the target leaf surface, solves the problems of inaccurate drug release and high photolysis rate of existing formulations, and improves efficacy and environmental safety.
Patent Information
- Application Number
- CN202511116024.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-11
- Publication Date
- 2025-11-25
AI Technical Summary
Existing cyhalofop-butyl formulations suffer from problems such as inaccurate drug release, high photosynthesis rate, short duration of effect, and significant environmental risks after application, making it difficult to achieve sustained control of target weeds and ensure environmental safety.
Using an azobenzene-mesoporous silica composite carrier, combined with molecularly imprinted polymers and photoresponsive carriers, a pulsed drug release is achieved through UV/Vis light modulation. This approach specifically identifies long-chain alkanes in the waxy layer of target leaves and designs a two-stage release mode.
This technology enables rapid and sustained release of the drug on the target leaf surface, increases retention, reduces photosynthesis and environmental risks, and improves the duration and safety of the drug's efficacy.
Smart Images
Figure SMS_1
Abstract
Description
Technical Field
[0001] This invention relates to the field of pesticide technology, and in particular to a method for preparing a dispersible oil suspension containing cyhalofop-butyl. Background Technology
[0002] In agricultural production, weed control is a crucial step in ensuring crop yield. Cyhalofop-butyl, a highly effective aryloxyphenoxypropionic acid herbicide, exhibits excellent control of noxious grasses such as Echinochloa crus-galli and is widely used in rice paddy weed management. However, existing cyhalofop-butyl formulations still face numerous technical bottlenecks in practical applications, severely limiting their efficacy and environmental safety. Traditional cyhalofop-butyl formulations primarily utilize passive diffusion for release, making precise control of drug release impossible. A "burst release" phenomenon frequently occurs after application, with release rates reaching as high as 78% within 24 hours. This leads to a significant loss of the active ingredient in a short period, reducing sustained control over target weeds and increasing the risk of pesticide residues in soil and water, potentially harming non-target organisms and the ecosystem. Furthermore, excessive non-target release results in actual dosages far exceeding theoretical requirements, increasing agricultural production costs and exacerbating the development of herbicide resistance in weeds.
[0003] Furthermore, cyhalofop-butyl is sensitive to ultraviolet light and is prone to photodegradation under natural light conditions. The photodegradation rate of traditional formulations can reach 25-30% within 48 hours, significantly shortening the effective period of the herbicide. Although some studies have attempted to add single light stabilizers, the light stabilization effect is limited because they cannot simultaneously address multiple photodegradation pathways such as singlet oxygen attack and direct ultraviolet degradation, making it difficult to meet the long-term control needs in the field. Summary of the Invention
[0004] The purpose of this invention is to provide a method for preparing a dispersible oil suspension containing cyhalofop-butyl, thereby at least partially solving the above-mentioned problems.
[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing a dispersible oil suspension containing cyhalofop-butyl, comprising the following steps: Mesoporous silica was synthesized using tetraethyl orthosilicate, mesoporous silica nanoparticles, ammonia, ethanol, and water as raw materials. The mesoporous silica was subjected to aminosilanization treatment with 3-aminopropyltriethoxysilane, followed by azobenzene grafting treatment with 4-phenylazobenzoic acid to obtain a photoresponsive carrier. Cyhalofop-butyl was mixed with the photoresponsive carrier and then subjected to vacuum rotary evaporation until dry to obtain a drug-loaded photoresponsive carrier. Molecularly imprinted polymers were synthesized and molecularly imprinted polymer microparticles were obtained by Soxhlet extraction. The molecularly imprinted polymer microparticles and the drug-loaded photoresponsive carrier were dispersed in a solvent and treated with octadecyltrimethoxysilane to obtain the modified drug-loaded carrier. The modified drug carrier was added to the oil phase, and after grinding and refining, the spiropyran derivative was added and stirred evenly under light-protected conditions. Crosslinking was induced by UV irradiation, and the pH was adjusted to 6.8-7 by adding buffer solution.
[0006] Furthermore, the synthesis of the mesoporous silica includes the following steps: Dissolve hexadecyltrimethylammonium bromide in deionized water, add ammonia water and stir at 60°C until homogeneous; Add ethyl n-silane dropwise and react for 6 hours, then centrifuge to collect the precipitate. After washing three times with ethanol, it was calcined at 550℃ for 6 hours.
[0007] Furthermore, mesoporous silica was dispersed in toluene, and 3-aminopropyltriethoxysilane was added and refluxed for 12 h to perform aminosilanization treatment. Azobenzene grafting treatment was performed by adding 4-phenylazobenzoic acid and reacting it for 24 h with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide as catalysts.
[0008] Furthermore, cyhalofop-butyl was dissolved in a solvent and then a photoresponsive carrier was added. The mixture was then subjected to vacuum rotary evaporation at 40°C until dry. The solvent is dichloromethane or acetone, and the drug loading capacity of the modified drug carrier is 35-40%.
[0009] Furthermore, the preparation of the molecularly imprinted polymer microparticles includes the following steps: Heptane, methacrylic acid, and ethylene glycol dimethacrylate were dissolved in acetonitrile; Azobisisobutyronitrile (AIBN) was added and the polymerization reaction was carried out at 60°C for 12 hours. Heptane was removed by Soxhlet extraction for 48 hours under conditions of methanol to acetic acid volume ratio of 9:1 to obtain synthetic molecularly imprinted polymer particles.
[0010] Furthermore, the molecularly imprinted polymer microparticles and the drug-loaded photoresponsive carrier were dispersed in toluene, and octadecyltrimethoxysilane was added. After reacting at 110°C for 8 hours, the mixture was centrifuged, dried, and collected.
[0011] Furthermore, the preparation of the oil phase includes the following steps: Methyl oleate and emulsifier were mixed evenly; modified lignin sulfonate and organobentonite were added and sheared at 10,000 rpm for 30 min at 60°C to obtain the pre-oil phase; The light stabilizer was added to the pre-oil phase and mixed. The mixture was then ultrasonically treated for 15 minutes at 600W and 20kHz using an ultrasonic probe. During the ultrasonic treatment, the temperature was controlled to be below 40℃ using an ice bath.
[0012] Furthermore, the modified drug carrier was added to the oil phase and circulated and ground for 3-4 hours using a horizontal grinding mill with zirconium beads of 0.3 mm in diameter, a filling rate of 80%, and a linear velocity of 10-13 m / s. Add the spiropyran derivative and stir at 3000 rpm for 1 hour under light-protected conditions. Analyze the mixture at 365 nm and 10-20 mW / cm². 2 Irradiate with ultraviolet light for 5 minutes under the specified conditions.
[0013] On the other hand, the present invention also provides a cyanflufenicol dispersible oil suspension, wherein the suspension prepared according to the above preparation method comprises the following materials in mass percentage: 10-20% Cyhalofop-butyl, 5-10% photoresponsive carrier, 40-60% methyl oleate, 3-8% molecularly imprinted polymer particles, 8-12% emulsifier, 5-8% modified lignin sulfonate, 1-3% organobentonite, and 2-5% light stabilizer.
[0014] On the other hand, the present invention also provides an application of a cyhalofop-butyl dispersible oil suspension, wherein the suspension prepared according to the above preparation method is used in the field of pesticides.
[0015] Compared with the prior art, the beneficial effects of the present invention are: This invention is based on an azobenzene-mesoporous silica composite carrier, which undergoes reversible cis-trans isomerization under ultraviolet / visible light irradiation to achieve pulsed drug release. At 365nm ultraviolet light, azobenzene is converted to a cis structure, opening the pores and accelerating the release of cyhalofop-butyl; at 450nm visible light, the trans structure is restored, closing the pores and reducing non-target release. By modifying the carrier surface with molecularly imprinted polymers, it specifically recognizes long-chain alkanes in the waxy layer of *Erigeron breviscapus* leaves. Through photocontrol, a two-stage mode of "rapid release with UV activation at the initial stage of application → sustained release with visible light regulation during the duration" is achieved, increasing the target leaf surface retention by 2.1 times. Detailed Implementation
[0016] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.
[0017] This invention provides a method for preparing a dispersible oil suspension containing cyhalofop-butyl, comprising the following steps: Mesoporous silica was synthesized using tetraethyl orthosilicate, mesoporous silica nanoparticles, ammonia, ethanol, and water as raw materials. The mesoporous silica was subjected to aminosilanization treatment with 3-aminopropyltriethoxysilane, followed by azobenzene grafting treatment with 4-phenylazobenzoic acid to obtain a photoresponsive carrier. Cyhalofop-butyl was mixed with the photoresponsive carrier and then subjected to vacuum rotary evaporation until dry to obtain a drug-loaded photoresponsive carrier. Molecularly imprinted polymers were synthesized and molecularly imprinted polymer microparticles were obtained by Soxhlet extraction. The molecularly imprinted polymer microparticles and the drug-loaded photoresponsive carrier were dispersed in a solvent and treated with octadecyltrimethoxysilane to obtain the modified drug-loaded carrier. The modified drug carrier was added to the oil phase, and after grinding and refining, the spiropyran derivative was added and stirred evenly under light-protected conditions. Crosslinking was induced by UV irradiation, and the pH was adjusted to 6.8-7 by adding buffer solution.
[0018] In a further embodiment of this example, the synthesis of the mesoporous silica includes the following steps: Dissolve hexadecyltrimethylammonium bromide in deionized water, add ammonia water and stir at 60°C until homogeneous; Add ethyl n-silane dropwise and react for 6 hours, then centrifuge to collect the precipitate. After washing three times with ethanol, it was calcined at 550℃ for 6 hours.
[0019] In a further embodiment of this example, mesoporous silica is dispersed in toluene, and 3-aminopropyltriethoxysilane is added and refluxed for 12 h to perform aminosilanization treatment. Azobenzene grafting treatment was performed by adding 4-phenylazobenzoic acid and reacting it for 24 h with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide as catalysts.
[0020] In a further embodiment of this example, cyhalofop-butyl is dissolved in a solvent and then a photoresponsive carrier is added and vacuum rotary evaporated at 40°C until dry. The solvent is dichloromethane or acetone, and the drug loading capacity of the modified drug carrier is 35-40%.
[0021] In a further embodiment of this example, the preparation of the molecularly imprinted polymer microparticles includes the following steps: Heptane, methacrylic acid, and ethylene glycol dimethacrylate were dissolved in acetonitrile; Azobisisobutyronitrile (AIBN) was added and the polymerization reaction was carried out at 60°C for 12 hours. Heptane was removed by Soxhlet extraction for 48 hours under conditions of methanol to acetic acid volume ratio of 9:1 to obtain synthetic molecularly imprinted polymer particles.
[0022] In a further embodiment of this example, molecularly imprinted polymer microparticles and drug-loaded photoresponsive carriers are dispersed in toluene, and octadecyltrimethoxysilane is added. After reacting at 110°C for 8 hours, the mixture is centrifuged, dried, and collected.
[0023] In a further embodiment of this example, the preparation of the oil phase includes the following steps: Methyl oleate and emulsifier were mixed evenly; modified lignin sulfonate and organobentonite were added and sheared at 10,000 rpm for 30 min at 60°C to obtain the pre-oil phase; The light stabilizer was added to the pre-oil phase and mixed. The mixture was then ultrasonically treated for 15 minutes at 600W and 20kHz using an ultrasonic probe. During the ultrasonic treatment, the temperature was controlled to be below 40℃ using an ice bath.
[0024] In a further embodiment of this example, the modified drug carrier is added to the oil phase and circulated and ground for 3-4 hours using a horizontal grinding mill with zirconium beads of 0.3 mm in diameter, a filling rate of 80%, and a linear velocity of 10-13 m / s. Add the spiropyran derivative and stir at 3000 rpm for 1 hour under light-protected conditions. Analyze the mixture at 365 nm and 10-20 mW / cm². 2 Irradiate with ultraviolet light for 5 minutes under the specified conditions.
[0025] On the other hand, embodiments of the present invention also provide a cyanflufenicol dispersible oil suspension, the suspension prepared according to the above preparation method, wherein the suspension comprises the following materials in mass percentage: 10-20% Cyhalofop-butyl, 5-10% photoresponsive carrier, 40-60% methyl oleate, 3-8% molecularly imprinted polymer particles, 8-12% emulsifier, 5-8% modified lignin sulfonate, 1-3% organobentonite, and 2-5% light stabilizer.
[0026] On the other hand, embodiments of the present invention also provide an application of a cyhalofop-butyl dispersible oil suspension, wherein the suspension prepared according to the above preparation method is used in the field of pesticides.
[0027] Example 1 Hexadecyltrimethylammonium bromide was dissolved in deionized water, and ammonia was added and stirred at 60°C until homogeneous. Tetraethyl n-silane was added dropwise and reacted for 6 hours. The precipitate was collected by centrifugation. After washing with ethanol three times, the precipitate was calcined at 550°C for 6 hours to obtain mesoporous silica.
[0028] Mesoporous silica was dispersed in toluene, and 3-aminopropyltriethoxysilane was added and refluxed for 12 h to perform aminosilanization treatment. 4-Phenylazobenzoic acid was added and the reaction was catalyzed for 24 h with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide as catalysts to perform azobenzene grafting treatment.
[0029] Cyhalofop-butyl was dissolved in acetone and then added to a photoresponsive carrier. The mixture was then subjected to vacuum rotary evaporation at 40°C until dry.
[0030] Heptane, methacrylic acid, and ethylene glycol dimethacrylate were dissolved in acetonitrile; azobisisobutyronitrile was added and polymerization was carried out at 60°C for 12 h; heptane was removed by Soxhlet extraction for 48 h under the condition of methanol to acetic acid volume ratio of 9:1 to obtain synthetic molecularly imprinted polymer particles.
[0031] Molecularly imprinted polymer microparticles and drug-loaded photoresponsive carriers were dispersed in toluene, and octadecyltrimethoxysilane was added. The mixture was reacted at 110°C for 8 hours, then centrifuged and dried before collection.
[0032] Methyl oleate and emulsifier were mixed evenly; modified lignin sulfonate and organobentonite were added and sheared at 10,000 rpm for 30 min at 60°C to obtain the pre-oil phase; Nano-cerium oxide, benzophenone, and light stabilizer 770 were added to the pre-oil phase as a composite light stabilizer and mixed. The mixture was then ultrasonically treated for 15 minutes at 600W and 20kHz using an ultrasonic probe. During the ultrasonic treatment, the temperature was controlled to be below 40℃ using an ice bath.
[0033] The modified drug carrier was added to the oil phase and circulated and ground for 3 hours using a horizontal mill with zirconium beads of 0.3 mm in diameter, a filling rate of 80%, and a linear velocity of 10 m / s. Add the spiropyran derivative and stir at 3000 rpm for 1 h under light-protected conditions. Analyze the mixture at 365 nm and 10 mW / cm². 2 Irradiate with UV light for 5 minutes under the specified conditions, then add buffer solution to adjust the pH to 6.8.
[0034] The prepared suspending agent comprises the following materials by mass percentage: 10% Cyhalofop-butyl, 5% photoresponsive carrier, 59% methyl oleate, 5% molecularly imprinted polymer particles, 10% emulsifier, 6% modified lignin sulfonate, 2% organobentonite and 3% light stabilizer.
[0035] Example 2 Hexadecyltrimethylammonium bromide was dissolved in deionized water, and ammonia was added and stirred at 60°C until homogeneous. Tetraethyl n-silane was added dropwise and reacted for 6 hours. The precipitate was collected by centrifugation. After washing with ethanol three times, the precipitate was calcined at 550°C for 6 hours to obtain mesoporous silica.
[0036] Mesoporous silica was dispersed in toluene, and 3-aminopropyltriethoxysilane was added and refluxed for 12 h to perform aminosilanization treatment. 4-Phenylazobenzoic acid was added and the reaction was catalyzed for 24 h with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide as catalysts to perform azobenzene grafting treatment.
[0037] Cyhalofop-butyl was dissolved in acetone and then added to a photoresponsive carrier. The mixture was then subjected to vacuum rotary evaporation at 40°C until dry.
[0038] Heptane, methacrylic acid, and ethylene glycol dimethacrylate were dissolved in acetonitrile; azobisisobutyronitrile was added and polymerization was carried out at 60°C for 12 h; heptane was removed by Soxhlet extraction for 48 h under the condition of methanol to acetic acid volume ratio of 9:1 to obtain synthetic molecularly imprinted polymer particles.
[0039] Molecularly imprinted polymer microparticles and drug-loaded photoresponsive carriers were dispersed in toluene, and octadecyltrimethoxysilane was added. The mixture was reacted at 110°C for 8 hours, then centrifuged and dried before collection.
[0040] Methyl oleate and emulsifier were mixed evenly; modified lignin sulfonate and organobentonite were added and sheared at 10,000 rpm for 30 min at 60°C to obtain the pre-oil phase; Nano-cerium oxide, benzophenone, and light stabilizer 770 were added to the pre-oil phase as a composite light stabilizer and mixed. The mixture was then ultrasonically treated for 15 minutes at 600W and 20kHz using an ultrasonic probe. During the ultrasonic treatment, the temperature was controlled to be below 40℃ using an ice bath.
[0041] The modified drug carrier was added to the oil phase and circulated and ground for 3 hours using a horizontal mill with zirconium beads of 0.3 mm in diameter, a filling rate of 80%, and a linear velocity of 10 m / s. Add the spiropyran derivative and stir at 3000 rpm for 1 h under light-protected conditions. Analyze the mixture at 365 nm and 10 mW / cm². 2 Irradiate with UV light for 5 minutes under the specified conditions, then add buffer solution to adjust the pH to 6.8.
[0042] The prepared suspending agent comprises the following materials by mass percentage: 15% cyhalofop-butyl, 10% photoresponsive carrier, 49% methyl oleate, 5% molecularly imprinted polymer particles, 10% emulsifier, 6% modified lignin sulfonate, 2% organobentonite and 3% light stabilizer.
[0043] Example 3 Hexadecyltrimethylammonium bromide was dissolved in deionized water, and ammonia was added and stirred at 60°C until homogeneous. Tetraethyl n-silane was added dropwise and reacted for 6 hours. The precipitate was collected by centrifugation. After washing with ethanol three times, the precipitate was calcined at 550°C for 6 hours to obtain mesoporous silica.
[0044] Mesoporous silica was dispersed in toluene, and 3-aminopropyltriethoxysilane was added and refluxed for 12 h to perform aminosilanization treatment. 4-Phenylazobenzoic acid was added and the reaction was catalyzed for 24 h with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide as catalysts to perform azobenzene grafting treatment.
[0045] Cyhalofop-butyl was dissolved in acetone and then added to a photoresponsive carrier. The mixture was then subjected to vacuum rotary evaporation at 40°C until dry.
[0046] Heptane, methacrylic acid, and ethylene glycol dimethacrylate were dissolved in acetonitrile; azobisisobutyronitrile was added and polymerization was carried out at 60°C for 12 h; heptane was removed by Soxhlet extraction for 48 h under the condition of methanol to acetic acid volume ratio of 9:1 to obtain synthetic molecularly imprinted polymer particles.
[0047] Molecularly imprinted polymer microparticles and drug-loaded photoresponsive carriers were dispersed in toluene, and octadecyltrimethoxysilane was added. The mixture was reacted at 110°C for 8 hours, then centrifuged and dried before collection.
[0048] Methyl oleate and emulsifier were mixed evenly; modified lignin sulfonate and organobentonite were added and sheared at 10,000 rpm for 30 min at 60°C to obtain the pre-oil phase; Nano-cerium oxide, benzophenone, and light stabilizer 770 were added to the pre-oil phase as a composite light stabilizer and mixed. The mixture was then ultrasonically treated for 15 minutes at 600W and 20kHz using an ultrasonic probe. During the ultrasonic treatment, the temperature was controlled to be below 40℃ using an ice bath.
[0049] The modified drug carrier was added to the oil phase and circulated and ground for 3 hours using a horizontal mill with zirconium beads of 0.3 mm in diameter, a filling rate of 80%, and a linear velocity of 10 m / s. Add the spiropyran derivative and stir at 3000 rpm for 1 h under light-protected conditions. Analyze the mixture at 365 nm and 10 mW / cm². 2 Irradiate with UV light for 5 minutes under the specified conditions, then add buffer solution to adjust the pH to 6.8.
[0050] The prepared suspending agent comprises the following materials by mass percentage: 20% cyhalofop-butyl, 10% photoresponsive carrier, 41% methyl oleate, 8% molecularly imprinted polymer particles, 10% emulsifier, 6% modified lignin sulfonate, 2% organobentonite and 3% light stabilizer.
[0051] Example 4 Hexadecyltrimethylammonium bromide was dissolved in deionized water, and ammonia was added and stirred at 60°C until homogeneous. Tetraethyl n-silane was added dropwise and reacted for 6 hours. The precipitate was collected by centrifugation. After washing with ethanol three times, the precipitate was calcined at 550°C for 6 hours to obtain mesoporous silica.
[0052] Mesoporous silica was dispersed in toluene, and 3-aminopropyltriethoxysilane was added and refluxed for 12 h to perform aminosilanization treatment. 4-Phenylazobenzoic acid was added and the reaction was catalyzed for 24 h with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide as catalysts to perform azobenzene grafting treatment.
[0053] Cyhalofop-butyl was dissolved in acetone and then added to a photoresponsive carrier. The mixture was then subjected to vacuum rotary evaporation at 40°C until dry.
[0054] Heptane, methacrylic acid, and ethylene glycol dimethacrylate were dissolved in acetonitrile; azobisisobutyronitrile was added and polymerization was carried out at 60°C for 12 h; heptane was removed by Soxhlet extraction for 48 h under the condition of methanol to acetic acid volume ratio of 9:1 to obtain synthetic molecularly imprinted polymer particles.
[0055] Molecularly imprinted polymer microparticles and drug-loaded photoresponsive carriers were dispersed in toluene, and octadecyltrimethoxysilane was added. The mixture was reacted at 110°C for 8 hours, then centrifuged and dried before collection.
[0056] Methyl oleate and emulsifier were mixed evenly; modified lignin sulfonate and organobentonite were added and sheared at 10,000 rpm for 30 min at 60°C to obtain the pre-oil phase; Nano-cerium oxide, benzophenone, and light stabilizer 770 were added to the pre-oil phase as a composite light stabilizer and mixed. The mixture was then ultrasonically treated for 15 minutes at 600W and 20kHz using an ultrasonic probe. During the ultrasonic treatment, the temperature was controlled to be below 40℃ using an ice bath.
[0057] The modified drug carrier was added to the oil phase and circulated and ground for 3 hours using a horizontal mill with zirconium beads of 0.3 mm in diameter, a filling rate of 80%, and a linear velocity of 11 m / s. Add the spiropyran derivative and stir at 3000 rpm for 1 h under light-protected conditions. Analyze the mixture at 365 nm and 10 mW / cm².2 Irradiate with UV light for 5 minutes under the specified conditions, then add buffer solution to adjust the pH to 6.8.
[0058] The prepared suspending agent comprises the following materials by mass percentage: 15% cyhalofop-butyl, 10% photoresponsive carrier, 49% methyl oleate, 5% molecularly imprinted polymer particles, 10% emulsifier, 6% modified lignin sulfonate, 2% organobentonite and 3% light stabilizer.
[0059] Example 5 Hexadecyltrimethylammonium bromide was dissolved in deionized water, and ammonia was added and stirred at 60°C until homogeneous. Tetraethyl n-silane was added dropwise and reacted for 6 hours. The precipitate was collected by centrifugation. After washing with ethanol three times, the precipitate was calcined at 550°C for 6 hours to obtain mesoporous silica.
[0060] Mesoporous silica was dispersed in toluene, and 3-aminopropyltriethoxysilane was added and refluxed for 12 h to perform aminosilanization treatment. 4-Phenylazobenzoic acid was added and the reaction was catalyzed for 24 h with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide as catalysts to perform azobenzene grafting treatment.
[0061] Cyhalofop-butyl was dissolved in acetone and then added to a photoresponsive carrier. The mixture was then subjected to vacuum rotary evaporation at 40°C until dry.
[0062] Heptane, methacrylic acid, and ethylene glycol dimethacrylate were dissolved in acetonitrile; azobisisobutyronitrile was added and polymerization was carried out at 60°C for 12 h; heptane was removed by Soxhlet extraction for 48 h under the condition of methanol to acetic acid volume ratio of 9:1 to obtain synthetic molecularly imprinted polymer particles.
[0063] Molecularly imprinted polymer microparticles and drug-loaded photoresponsive carriers were dispersed in toluene, and octadecyltrimethoxysilane was added. The mixture was reacted at 110°C for 8 hours, then centrifuged and dried before collection.
[0064] Methyl oleate and emulsifier were mixed evenly; modified lignin sulfonate and organobentonite were added and sheared at 10,000 rpm for 30 min at 60°C to obtain the pre-oil phase; Nano-cerium oxide, benzophenone, and light stabilizer 770 were added to the pre-oil phase as a composite light stabilizer and mixed. The mixture was then ultrasonically treated for 15 minutes at 600W and 20kHz using an ultrasonic probe. During the ultrasonic treatment, the temperature was controlled to be below 40℃ using an ice bath.
[0065] The modified drug carrier was added to the oil phase and circulated and ground for 3 hours using a horizontal mill with zirconium beads of 0.3 mm in diameter, a filling rate of 80%, and a linear velocity of 12 m / s. Add the spiropyran derivative and stir at 3000 rpm for 1 h under light-protected conditions. Analyze the mixture at 365 nm and 10 mW / cm². 2 Irradiate with UV light for 5 minutes under the specified conditions, then add buffer solution to adjust the pH to 6.8.
[0066] The prepared suspending agent comprises the following materials by mass percentage: 15% cyhalofop-butyl, 10% photoresponsive carrier, 49% methyl oleate, 5% molecularly imprinted polymer particles, 10% emulsifier, 6% modified lignin sulfonate, 2% organobentonite and 3% light stabilizer.
[0067] Example 6 Hexadecyltrimethylammonium bromide was dissolved in deionized water, and ammonia was added and stirred at 60°C until homogeneous. Tetraethyl n-silane was added dropwise and reacted for 6 hours. The precipitate was collected by centrifugation. After washing with ethanol three times, the precipitate was calcined at 550°C for 6 hours to obtain mesoporous silica.
[0068] Mesoporous silica was dispersed in toluene, and 3-aminopropyltriethoxysilane was added and refluxed for 12 h to perform aminosilanization treatment. 4-Phenylazobenzoic acid was added and the reaction was catalyzed for 24 h with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide as catalysts to perform azobenzene grafting treatment.
[0069] Cyhalofop-butyl was dissolved in acetone and then added to a photoresponsive carrier. The mixture was then subjected to vacuum rotary evaporation at 40°C until dry.
[0070] Heptane, methacrylic acid, and ethylene glycol dimethacrylate were dissolved in acetonitrile; azobisisobutyronitrile was added and polymerization was carried out at 60°C for 12 h; heptane was removed by Soxhlet extraction for 48 h under the condition of methanol to acetic acid volume ratio of 9:1 to obtain synthetic molecularly imprinted polymer particles.
[0071] Molecularly imprinted polymer microparticles and drug-loaded photoresponsive carriers were dispersed in toluene, and octadecyltrimethoxysilane was added. The mixture was reacted at 110°C for 8 hours, then centrifuged and dried before collection.
[0072] Methyl oleate and emulsifier were mixed evenly; modified lignin sulfonate and organobentonite were added and sheared at 10,000 rpm for 30 min at 60°C to obtain the pre-oil phase; Nano-cerium oxide, benzophenone, and light stabilizer 770 were added to the pre-oil phase as a composite light stabilizer and mixed. The mixture was then ultrasonically treated for 15 minutes at 600W and 20kHz using an ultrasonic probe. During the ultrasonic treatment, the temperature was controlled to be below 40℃ using an ice bath.
[0073] The modified drug carrier was added to the oil phase and circulated and ground for 3 hours using a horizontal mill with zirconium beads of 0.3 mm in diameter, a filling rate of 80%, and a linear velocity of 13 m / s. Add the spiropyran derivative and stir at 3000 rpm for 1 h under light-protected conditions. Analyze the mixture at 365 nm and 10 mW / cm². 2 Irradiate with UV light for 5 minutes under the specified conditions, then add buffer solution to adjust the pH to 6.8.
[0074] The prepared suspending agent comprises the following materials by mass percentage: 15% cyhalofop-butyl, 10% photoresponsive carrier, 49% methyl oleate, 5% molecularly imprinted polymer particles, 10% emulsifier, 6% modified lignin sulfonate, 2% organobentonite and 3% light stabilizer.
[0075] Comparative Example 1 Hexadecyltrimethylammonium bromide was dissolved in deionized water, and ammonia was added and stirred at 60°C until homogeneous. Tetraethyl n-silane was added dropwise and reacted for 6 hours. The precipitate was collected by centrifugation. After washing with ethanol three times, the precipitate was calcined at 550°C for 6 hours to obtain mesoporous silica.
[0076] Mesoporous silica was dispersed in toluene, and 3-aminopropyltriethoxysilane was added and refluxed for 12 h to perform aminosilanization treatment. 4-Phenylazobenzoic acid was added and the reaction was catalyzed for 24 h with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide as catalysts to perform azobenzene grafting treatment.
[0077] Cyhalofop-butyl was dissolved in acetone and then added to a photoresponsive carrier. The mixture was then subjected to vacuum rotary evaporation at 40°C until dry.
[0078] Heptane, methacrylic acid, and ethylene glycol dimethacrylate were dissolved in acetonitrile; azobisisobutyronitrile was added and polymerization was carried out at 60°C for 12 h; heptane was removed by Soxhlet extraction for 48 h under the condition of methanol to acetic acid volume ratio of 9:1 to obtain synthetic molecularly imprinted polymer particles.
[0079] Molecularly imprinted polymer microparticles and drug-loaded photoresponsive carriers were dispersed in toluene, and octadecyltrimethoxysilane was added. The mixture was reacted at 110°C for 8 hours, then centrifuged and dried before collection.
[0080] Methyl oleate and emulsifier were mixed evenly; modified lignin sulfonate and organobentonite were added and sheared at 10,000 rpm for 30 min at 60°C to obtain the pre-oil phase; Nano-cerium oxide, benzophenone, and light stabilizer 770 were added to the pre-oil phase as a composite light stabilizer and mixed. The mixture was then ultrasonically treated for 15 minutes at 600W and 20kHz using an ultrasonic probe. During the ultrasonic treatment, the temperature was controlled to be below 40℃ using an ice bath.
[0081] The modified drug carrier was added to the oil phase and circulated and ground for 2 hours using a horizontal mill with zirconium beads of 0.3 mm in diameter, a filling rate of 80%, and a linear velocity of 12 m / s. Add the spiropyran derivative and stir at 3000 rpm for 1 h under light-protected conditions. Analyze the mixture at 365 nm and 5 mW / cm². 2 Irradiate with UV light for 5 minutes under the specified conditions, then add buffer solution to adjust the pH to 6.8.
[0082] The prepared suspending agent comprises the following materials by mass percentage: 15% cyhalofop-butyl, 10% photoresponsive carrier, 49% methyl oleate, 5% molecularly imprinted polymer particles, 10% emulsifier, 6% modified lignin sulfonate, 2% organobentonite and 3% light stabilizer.
[0083] Comparative Example 2 Hexadecyltrimethylammonium bromide was dissolved in deionized water, and ammonia was added and stirred at 60°C until homogeneous. Tetraethyl n-silane was added dropwise and reacted for 6 hours. The precipitate was collected by centrifugation. After washing with ethanol three times, the precipitate was calcined at 550°C for 6 hours to obtain mesoporous silica.
[0084] Mesoporous silica was dispersed in toluene, and 3-aminopropyltriethoxysilane was added and refluxed for 12 h to perform aminosilanization treatment. 4-Phenylazobenzoic acid was added and the reaction was catalyzed for 24 h with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide as catalysts to perform azobenzene grafting treatment.
[0085] Cyhalofop-butyl was dissolved in acetone and then added to a photoresponsive carrier. The mixture was then subjected to vacuum rotary evaporation at 40°C until dry.
[0086] Heptane, methacrylic acid, and ethylene glycol dimethacrylate were dissolved in acetonitrile; azobisisobutyronitrile was added and polymerization was carried out at 60°C for 12 h; heptane was removed by Soxhlet extraction for 48 h under the condition of methanol to acetic acid volume ratio of 9:1 to obtain synthetic molecularly imprinted polymer particles.
[0087] Molecularly imprinted polymer microparticles and drug-loaded photoresponsive carriers were dispersed in toluene, and octadecyltrimethoxysilane was added. The mixture was reacted at 110°C for 8 hours, then centrifuged and dried before collection.
[0088] Methyl oleate and emulsifier were mixed evenly; modified lignin sulfonate and organobentonite were added and sheared at 10,000 rpm for 30 min at 60°C to obtain the pre-oil phase; Nano-cerium oxide, benzophenone, and light stabilizer 770 were added to the pre-oil phase as a composite light stabilizer and mixed. The mixture was then ultrasonically treated for 15 minutes at 600W and 20kHz using an ultrasonic probe. During the ultrasonic treatment, the temperature was controlled to be below 40℃ using an ice bath.
[0089] The modified drug carrier was added to the oil phase and circulated and ground for 5 hours using a horizontal mill with zirconium beads of 0.3 mm in diameter, a filling rate of 80%, and a linear velocity of 13 m / s. Add the spiropyran derivative and stir at 3000 rpm for 1 h under light-protected conditions. Analyze the mixture at 365 nm and 10 mW / cm². 2 Irradiate with UV light for 5 minutes under the specified conditions, then add buffer solution to adjust the pH to 6.8.
[0090] The prepared suspending agent comprises the following materials by mass percentage: 15% cyhalofop-butyl, 10% photoresponsive carrier, 49% methyl oleate, 5% molecularly imprinted polymer particles, 10% emulsifier, 6% modified lignin sulfonate, 2% organobentonite and 3% light stabilizer.
[0091] The suspensions prepared in Examples 1-6 and Comparative Examples 1 and 2 were subjected to drug loading detection by high performance liquid chromatography, photolysis rate detection by 48 hours of simulated sunlight irradiation, D90 particle size detection by ISO13320, release rate detection by 24 hours of dialysis bag method, and leaf retention rate detection by fluorescence tracer method. The test data are shown in Table 1 below. Table 1
[0092] In summary, as shown in Table 1, the suspension prepared by this method achieves "precise delivery + intelligent release," significantly improving the target leaf surface retention. The release rate within 24 hours is optimized from 78% of the traditional formulation to over 80%, with a maximum of 91.3%. The composite photostable system can reduce the photolysis rate of cyhalofop-butyl from 28% of the traditional formulation to <10%. As shown in Comparative Examples 1 and 2, the grinding time process can destroy the emulsion structure, affecting performance. Insufficient UV irradiation intensity leads to inadequate cross-linking, which in turn affects the performance of the suspension.
[0093] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.
Claims
1. A method for preparing a dispersible oil suspension containing cyhalofop-butyl, characterized in that, Includes the following steps: Mesoporous silica was synthesized using tetraethyl orthosilicate, mesoporous silica nanoparticles, ammonia, ethanol, and water as raw materials. The mesoporous silica was subjected to aminosilanization treatment with 3-aminopropyltriethoxysilane, followed by azobenzene grafting treatment with 4-phenylazobenzoic acid to obtain a photoresponsive carrier. Cyhalofop-butyl was mixed with the photoresponsive carrier and then subjected to vacuum rotary evaporation until dry to obtain a drug-loaded photoresponsive carrier. Molecularly imprinted polymers were synthesized and molecularly imprinted polymer microparticles were obtained by Soxhlet extraction. The molecularly imprinted polymer microparticles and the drug-loaded photoresponsive carrier were dispersed in a solvent and treated with octadecyltrimethoxysilane to obtain the modified drug-loaded carrier. The modified drug carrier was added to the oil phase, and after grinding and refining, the spiropyran derivative was added and stirred evenly under light-protected conditions. Crosslinking was induced by UV irradiation, and the pH was adjusted to 6.8-7 by adding buffer solution.
2. The method for preparing a cyhalofop-butyl-containing dispersible oil suspension according to claim 1, characterized in that: The synthesis of the mesoporous silica includes the following steps: Dissolve hexadecyltrimethylammonium bromide in deionized water, add ammonia water and stir at 60°C until homogeneous; Add ethyl n-silane dropwise and react for 6 hours, then centrifuge to collect the precipitate. After washing three times with ethanol, it was calcined at 550℃ for 6 hours.
3. The method for preparing a cyhalofop-butyl-containing dispersible oil suspension according to claim 1, characterized in that: Mesoporous silica was dispersed in toluene, and 3-aminopropyltriethoxysilane was added and refluxed for 12 h to perform aminosilanization treatment. Azobenzene grafting treatment was performed by adding 4-phenylazobenzoic acid and reacting it for 24 h with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide as catalysts.
4. The method for preparing a cyhalofop-butyl-containing dispersible oil suspension according to claim 1, characterized in that: Cyhalofop-butyl was dissolved in a solvent and then added to a photoresponsive carrier. The mixture was then subjected to vacuum rotary evaporation at 40°C until dry. The solvent is dichloromethane or acetone, and the drug loading capacity of the modified drug carrier is 35-40%.
5. The method for preparing a cyhalofop-butyl-containing dispersible oil suspension according to claim 1, characterized in that: The preparation of the molecularly imprinted polymer microparticles includes the following steps: Heptane, methacrylic acid, and ethylene glycol dimethacrylate were dissolved in acetonitrile; Azobisisobutyronitrile (AIBN) was added and the polymerization reaction was carried out at 60°C for 12 hours. Heptane was removed by Soxhlet extraction for 48 hours under conditions of methanol to acetic acid volume ratio of 9:1 to obtain synthetic molecularly imprinted polymer particles.
6. The method for preparing a cyhalofop-butyl-containing dispersible oil suspension according to claim 1, characterized in that: Molecularly imprinted polymer microparticles and drug-loaded photoresponsive carriers were dispersed in toluene, and octadecyltrimethoxysilane was added. The mixture was reacted at 110°C for 8 hours, then centrifuged and dried before collection.
7. The method for preparing a cyhalofop-butyl-containing dispersible oil suspension according to claim 1, characterized in that: The preparation of the oil phase includes the following steps: Methyl oleate and emulsifier were mixed evenly; modified lignin sulfonate and organobentonite were added and sheared at 10,000 rpm for 30 min at 60°C to obtain the pre-oil phase; The light stabilizer was added to the pre-oil phase and mixed. The mixture was then ultrasonically treated for 15 minutes at 600W and 20kHz using an ultrasonic probe. During the ultrasonic treatment, the temperature was controlled to be below 40℃ using an ice bath.
8. The method for preparing a cyhalofop-butyl-containing dispersible oil suspension according to claim 1, characterized in that: The modified drug carrier was added to the oil phase and circulated and ground for 3-4 hours using a horizontal mill with zirconium beads of 0.3 mm in diameter, a filling rate of 80%, and a linear velocity of 10-13 m / s. Add the spiropyran derivative and stir at 3000 rpm for 1 h under light-protected conditions. Analyze the mixture at 365 nm and 10-20 mW / cm². 2 Irradiate with ultraviolet light for 5 minutes under the specified conditions.
9. A dispersible oil suspension containing cyhalofop-butyl, characterized in that, The suspending agent prepared according to any one of claims 1-8 comprises the following materials by mass percentage: 10-20% Cyhalofop-butyl, 5-10% photoresponsive carrier, 40-60% methyl oleate, 3-8% molecularly imprinted polymer particles, 8-12% emulsifier, 5-8% modified lignin sulfonate, 1-3% organobentonite, and 2-5% light stabilizer.
10. An application of a cyhalofop-butyl dispersible oil suspension, characterized in that, The suspension prepared according to any one of claims 1-8 is used in the field of pesticides.