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

JESSER, EMILIANO; YEGUERMAN, CRISTHIAN ALAN; URRUTIA, RODRIGO IÑAKI; MURRAY, ANA PAULA; DOMINI, CLAUDIA; WERDIN-GONZÁLEZ, JORGE OMAR

PEST MANAGEMENT SCIENCE

JOHN WILEY & SONS LTD

Año: 2023

1526-498X

Background: The 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. Results: The 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. Conclusion: The NEs elaborated in this work can be considered as highly promising formulations for the development of new insecticides. © 2023 Society of Chemical Industry.