以β-环糊精制备除虫菊酯微胶囊及应用

Preparation of Pyrethrins Microcapsule by β-cyclodextrin and Application

摘要:

采用微胶囊技术将天然除虫菊酯包埋在β环糊精的中空疏水区以解决其在自然条件下不稳定的问题.制备的微胶囊包埋率为92.15%，载药率为8.5%，粒径范围为1~17 μm.结果表明微胶囊相对原药具有较好的热稳定性和缓释性能，且缓释行为符合一级动力学模型.微胶囊在4℃冰箱中储存稳定性良好，5个月后载药率下降率在20%以内.自然条件下，微胶囊相比原药制剂可以延长1~1.5倍的作用时间.制备的微胶囊对淡色库蚊、白纹伊蚊以及二化螟、蚜虫和粘虫具有较高的灭蚊灭虫活性，可在防治害虫时单独使用.

Abstract:

Natural pyrethrins was encapsulated in hollow hydrophobic part of β-cyclodextrin to protect it against natural degradation. The encapsulation efficiency and drug content of the pyrethrins microcapsule prepared were 92.15% and 8.5%, respectively, and the particle size ranged from 1 to 17 μm. It was demonstrated that the pyrethrins microcapsule had better thermal stability and slow-release capability than liquid pyrethrins. Its slow-release kinetics could be described as the first-order model. The storage stability of pyrethrins was improved after encapsulation. Results showed that the drug content decreased within 20% after 5 months at 4℃. Under natural conditions, microcapsules could also prolong the storage duration of pyrethrins by 1~1.5 times. The pyrethrins microcapsule in this study had high insecticidal activity against Culex pipiens pallens, Aedes albopictus, Chilo suppressalis, aphids and Myxodes armyworm, indicating that it was a promising pesticide for the control of pests.