金属离子配位组装制备负载高效氯氟氰菊酯的壳聚糖纳米颗粒及其对豌豆蚜虫的生物活性

Preparation of chitosan nanoparticles loaded with lambda-cyhalothrin by metal ion coordination assembly and their bioactivity against Acyrthosiphon pisum(Harris)

[目的]目前纳米农药复杂的制备工艺阻碍了其推广,亟需低能耗、低成本、简便的方法获得载药纳米颗粒,进而提高农药利用率。[方法]采用金属离子配位组装法,利用天然可降解、安全环保的壳聚糖材料制备了2.5%高效氯氟氰菊酯纳米颗粒,通过测定其释放性能和对豌豆蚜虫的室内生物活性来评估其应用效果。[结果]负载高效氯氟氰菊酯的纳米颗粒为球形,包封率为92.06%,平均粒径(D_(50))为202.83 nm。高效氯氟氰菊酯被纳米颗粒负载后提高了其热稳定性。在释放液中,2 h时纳米载药颗粒的累积释放率为59.25%。在48 h时负载高效氯氟氰菊酯的纳米颗粒对豌豆蚜虫的LC_(50)值为0.004 mg/L,高于乳油的0.006 mg/L和微米载药颗粒的0.01 mg/L。[结论]实验结果可为开发对叶部害虫具有优异防治效果的纳米制剂提供依据。

[Aims]Currently,the complex preparation process of nano-pesticides hinders their promotion.There is an urgent need for a simple method with low-energy consumption and lowcost to obtain pesticide-loaded nanoparticles in order to improve pesticide utilization.[Methods]Lambda-cyhalothrin 2.5%nanoparticles were prepared using natural biodegradable,safe and environmentally friendly chitosan material by metal ion coordination assembly method.The bioactivity was evaluated by measuring its release performance and bioactivity against Acyrthosiphon pisum in laboratory.[Results]The results showed that the nanoparticles loaded with lambda-cyhalothrin were spherical,the encapsulation rate was 92.06%,and the average particle size(D_(50))was 202.83 nm.The thermal stability of lambda-cyhalothrin was improved after it was loaded by nanoparticles.The cumulative release rate of nanoparticles was 59.25%at 2 h in the release solution.The LC_(50) values at 48 h of lambda-cyhalothrin-loaded nanoparticles to A.pisum was 0.004 mg/L,which was higher than that of emulsion(0.006 mg/L)and loaded by micron-particles(0.01 mg/L),respectively.[Conclusions]The results of this study could provide a basis for the development of nano-formulations with excellent control effect on leaf pests.