Preparation and properties of nano-controlled release formulation of emamectin benzoate
Nano-controlled release formulation based on mesoporous silica nanoparticles(MSNs)pro-vides an effective way for accurate pesticide delivery.In this study,temperature-responsive emamectin benzoate(EB)nano-controlled release formulation(EB@MSNs@K(NIPAAM-MAA))was prepared by sol-gel method.The appearance,release behavior,insecticidal activity and safety to non-target organisms were studied systematically.The results of TEM showed that the unloaded particles MSNs@K(NIPAAM-MAA)were round in shape,uniform in size and rough in surface,and the particle size is distributed in the range of 150～170 nm.The results of BET,FTIR and TGA showed that the thermosensitive polymer was successfully grafted(grafting rate of 19.5％)and EB was successfully loaded into MSNs(drug load-ing of 15.7％).Release behavior studies showed that higher temperatures(28 ℃ and 24 ℃)were be-nefical for the release of EB.Both EB@MSNs@K(NIPAAM-MAA)and commercial EB@EC had rea-sonable control effect against Spodoptera frugiperda at the same concentration,but the insecticidal effect of EB@EC was lower than that of EB@MSNs@K(NIPAAM-MAA)with time extension,indicating that EB@MSNs@K(NIPAAM-MAA)had a longer effective duration.The biosafety test showed that the LC50 of EB@MSNs@K(NIPAAM-MAA)was 26.62 mg/kg at 14 d on earthworms,which showed low toxici-ty.In addition,EB@MSNs@K(NIPAAM-MAA)had no significant effect on the changes in chlorophyll content of corn leaves at a range of concentrations.
万方数据
维普
