Development and characterization of nanoemulsions loaded with essential oil and β‐cypermethrin and their bioefficacy on insect pest of economic and medical importance

Abstract

BackgroundThe development of novel and ecofriendly tools plays an important role in insect pest management. Nanoemulsions (NEs) based on essential oils (EOs) offer a safer alternative for human health and the environment. This study aimed to elaborate and evaluate the toxicological effects of NEs containing peppermint or palmarosa EOs combined with β‐cypermethrin (β‐CP) using ultrasound technique.ResultsThe optimized ratio of active ingredients to surfactant was 1:2. The NEs containing peppermint EO combined with β‐CP (NEs peppermint/β‐CP) were polydisperse with two peaks at 12.77 nm (33.4% intensity) and 299.1 nm (66.6% intensity). However, the NEs containing palmarosa EO combined with β‐CP (NEs palmarosa/β‐CP) were monodisperse with a size of 104.5 nm. Both NEs were transparent and stable for 2 months. The insecticidal effect of NEs was evaluated against Tribolium castaneum and Sitophilus oryzae adults, as well as Culex pipiens pipiens larvae. On all these insects, NEs peppermint/β‐CP enhanced pyrethroid bioactivity from 4.22‐ to 16‐folds while NEs palmarosa/β‐CP, from 3.90‐ to 10.6‐folds. Moreover, both NEs maintained high insecticidal activities against all insects for 2 months, although a slight increase of the particle size was detected.ConclusionThe NEs elaborated in this work can be considered as highly promising formulations for the development of new insecticides. © 2023 Society of Chemical Industry.

Nano-Agrochemicals as Substitutes for Pesticides: Prospects and Risks

“…Neem oil-containing nanoemulsions have proven effective against two economically significant agricultural pests: the red flour beetle ( Tribolium castaneum ) and the rice weevil ( Sitophilus oryzae ) [ 176 ]. In terms of pest control in particular, nanoemulsions present a promising alternative that can improve safety in human health and environmental aspects with the least amount of harm to the environment and non-targeted organisms [ 176 , 177 ]. Table 3 summarizes the types, composition, effectiveness, and ecological risks of the specified nanoemulsions.…”