Knockdown of Fruit Flies by Imidacloprid Nanoaerosol

Abstract

This report describes the effects of nanoaerosol particles (NAPs) from imidacloprid (IMI) on fruit flies. NAPs were produced using a newly developed generator which employs electro-hydrodynamic atomization of IMI solution in ethanol. Exposure of Drosophila melanogaster to the IMI NAPs at a concentration of C = 2.7 ± 0.1 ng/cm(3) caused knockdown in half of the flies in T50 = 88 ± 14 min at 22 °C and in T50 = 36 ± 2 min at 33 °C. A number of special experiments precluded IMI volatilization and contact or oral action of IMI upon exposure to the NAPs. It was shown that only the fraction of NAPs in the size range of 7-300 nm is responsible for the knockdown and that dependence of T50 on the NAPs' fraction mass follows Haber's rule, C × T50 = const. Comparison with the oral doses obtained when flies were fed an IMI-sucrose mixture revealed that the inhaled doses that caused knockdown were 2 orders of magnitude lower than the oral ones. This new technology may be used to quickly eliminate insects with nanoaerosols of nonvolatile insecticides in greenhouses and other closed environments.

Reversible and Irreversible Mechanical Damaging of Large Double-Stranded DNA upon Electrospraying

“…Although ES of nucleic acids has not yet become a widespread method, it is employed in mass spectrometry, gene transfection, and fabrication of microarrays . ES-generated DNA nanoaerosols may become efficient agents for gene therapy with precise and selective drug delivery. − The ES process involves high-energy events such as (i) intensive flows and vortexes in the Taylor cone, , (ii) high-speed flow in the liquid jet, , and (iii) high-energy molecular species formed in the corona discharge which often accompanies ES . Therefore, when biological molecules are subjected to electrospraying, the potential for them to be chemically modified, fragmented, or somehow otherwise damaged upon ES must be considered.…”