Scientific Reports
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2017
·Vol. 7
·期 1
·1-10
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IF 4.259
Huang Bin Bin,Zhang Shao Fei,Chen Peng Hao,Wu Gang
The dynamics of release and degradation of the microencapsulation formulation containing spinosad (SP) and emamectin benzoate (EM) were evaluated in the present study. SP and EM were microencapsulated using biodegradable poly-lactic acid (PLA) as the wall material. Their release from and degradation within the prepared SP and EM microspheres (SP-EM-microspheres) were studied. It was found that the encapsulation significantly prolonged the insecticide release. The release could be further extended if the external aqueous phase was pre-saturated with the insecticides and the microspheres were additionally coated with gelatin. On the other hand, increasing the water content of the emulsion or the hydrophilic polycaprolactone (PCL) content in the PLA/PCL mixture accelerated the release. Due to the photolysis and hydrolysis of SP and EM by sunlight, the toxicity of the non-encapsulated insecticides in water declined continuously from 0 through the 9 th day (d), and dissipated in 13 d. In contrast, an aqueous suspension containing 5% SP-EM-microspheres maintained a mostly constant toxicity to Plutella xylostella for 17 d. The biodegradable SP-EM-microspheres showed significantly higher long-term toxicity to P. xylostella due to lower release, reduced photolysis and hydrolysis of the encapsulated insecticides, which were affected by the varied preparation conditions.
研究领域:
农药科学
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环境生物学
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材料科学
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产品关联
DOI
PubMed
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
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2019
·
IF 3.074
Enming Dong,Ziming Yang,Chuang Zhou,Chao Wang,Sidong Li,Qianqian Ouyang,Lingxue Kong,Zuyu He,Jianghui Xie,Puwang Li,Peihui Yang
In this paper, we synthesized amphiphilic chitosan using one-pot method with the goal to develop delivery system for the natural pesticide spinosad . Chitosan-Isoleucine-Polyethylene glycol methyl ether (CIP) copolymers based nanomicelles (CIPNMs) were prepared by self-assembly with the assistance of ultrasonic treatment and then the spinosad was loaded on the micelles . Sphere-shaped spinosad-loaded CIPNMs (SSD@CIPNMs) with the particle sizes of approximately 454.9 nm were obtained with the CIP co -polymers. The shell of CIPNMs could effectively prevent the photodegradation of spinosad and played a role of protective barrier. In addition, the prepared SSD@CIPNMs not only delayed the release of spinosad but also had a property of pH-responsive. The release rate of SSD@CIPNMs at pH = 6.4 was greater than that of at pH = 7.0. And, the contact angle of SSD@CIPNMs on banana leaves surface was 60.47°, which meant SSD@CIPNMs had a good affinity with banana leaves. Furthermore, SSD@CIPNMs showed higher antifungal activity against Fusarium oxysporum compared with the unencapsulated spinosad at the same drug dose. This work was contribution to the development of nano-drug carrier systems of natural polymer materials, with a great potential for targeted treatment of banana wilt.
研究领域:
农业科学
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植物病理学
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材料科学
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产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2019
·
IF 3.074
Chuang Zhou,Ziming Yang,Li Zhang,Enming Dong,Zuyu He,Xianwu Liu,Chao Wang,Yan Yang,Jing Jiao,Yunhao Liu,Yu Chen,Puwang Li
In this work, carboxymethyl chitosan-graft-eleostearic acid (CMCS-g-EA) was synthesized via the amide reaction between the amino groups of carboxymethyl chitosan and the carboxyl group of eleostearic acid, and then mPEG-NH 2 was grafted to CMCS-g-EA to prepare amphiphilic polymers (mPEG-CMCS-g-EA). The chemical structures of the above conjugates were characterized by FT-IR and 1 H NMR. Both CMCS-g-EA and mPEG-CMCS-g-EA based nano-vesicles were prepared by ultrasonic self-assembly method and they exhibited a low critical aggregation concentration (CAC) of 14.97 μg/mL, 16.82 μg/mL, respectively. The spinosad-loaded mPEG-CMCS-g-EA nano-vesicles (SSD@mPEG-CMCS-g-EA NVs) were spherical in shape with an average diameter of 502.8 nm and the zeta potential of −25.60 mV. The encapsulation efficiency (EE) and drug loading content (LC) of SSD@mPEG-CMCS-g-EA nano-vesicles were 42.00%, 23.07%, respectively. In vitro release revealed that the SSD@mPEG-CMCS-g-EA nano-vesicles exhibited a sustained and pH-responsive drug release property, and could significantly enhance the photostability of spinosad . Furthermore, the toxicological tests demonstrated that the SSD@mPEG-CMCS-g-EA nano-vesicles could efficiently inhibit the growth and development of Helicoverpa armigera . These results indicated that the SSD@mPEG-CMCS-g-EA nano-vesicles were highly potential for the treatment of Helicoverpa armigera .
研究领域:
农药科学
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生物材料学
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昆虫学
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DOI
高影响因子
PEST MANAGEMENT SCIENCE
·
2024
·
IF 3.8
Hongxiao Yu,Yunqi Li,Hong Wang,Lei Zhang,Penghui Suo,Tianyun Su,Qian Han
BACKGROUNDS In order to provide a long-lasting formulation for spinosad (SP) targeting larval stages of Aedes aegypti (Linnaeus) and others alike, a SP tablet was developed based on microspheres, using polylactic acid as inside coating material. The microspheres were encapsulated using polyethylene glycol and 1-hexadecanol to form a sustained-release SP tablet. Micromorphology, active ingredient loading, structure identification, photolysis resistance and biological activity were evaluated in this report. RESULTS (i) The SP microspheres had an average particle size of 6.16 ± 2.28 μm, low adhesion and good dispersion as evaluated by scanning electron microscopy and morphology. (ii) The average active ingredient loading and encapsulation of SP microspheres were 32.80 ± 0.74% and 78.41 ± 2.22%, respectively. (iii) The chemical structure of encapsulated SP was confirmed by Fourier transform infrared and 1 H-nuclear magnetic resonance. (iv) The photostability of the microspheres and the tablets were evaluated. The results showed that DT 50 (time required to dissipate 50% of the mass originally present) of SP was 0.95 days in microspheres and 6.94 days in tablets. (v) The long-term insecticidal activity of SP tablets was investigated, and the tablet had a long-lasting activity against the mosquito larvae, showing 100% larval mortality for 63 days. CONCLUSIONS The study provided a new long-lasting formulation of SP, which displayed good efficacy in the control of Ae. aegypti larvae. © 2024 Society of Chemical Industry.
研究领域:
药学
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害虫控制
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微囊技术
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公共卫生
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）