Chitosan nanocapsules of tarragon essential oil with low cytotoxicity and long-lasting activity as a green nano-larvicide

Frequent use of synthetic larvicides has led to the development of resistance in many species of mosquitoes as well as risk of environmental pollution. Recently, encapsulating essential oils (EOs) in surfactants or polymers is being employed as an approach to control the volatility of EOs as green larvicides. In this research, components of tarragon (Artemisia dracunculus) essential oil were identified by GC-MS analysis. Forty-eight components were identified, with 5 major components including estragole (67.623%), cis-Ocimene (8.691%), beta-Ocimene Y (7.577%), Limonene (4.338%) and 3-Methoxy cinnam aldehyde (1.49%). Tarragon EO was encapsulated in chitosan nanocapsules using ionic gelation method and confirmed by FT-IR analysis. Encapsulation efficiency and size of the chitosan nanocapsules were determined 34.91 ± 2% and 203 ± 16 nm, respectively. For the first time, a long-lasting green larvicide was reported which remained active for 10 days, against Anopheles stephensi. Furthermore, cytotoxicity of the nanoformulation was found to be similar to that of temephos on human skin normal cells (HFFF2). This nanoformulation can be a good alternative for synthetic larvicides due to its long-lasting activity, proper effectiveness and also its green constituents.