Acaricidal activity of zinc oxide nanoparticles against Hyalomma spp. in vitro

Hyalomma spp. is responsible for transmission of protozoan, bacterial, rickettsial and viral diseases in humans and animals. Recently, there was a wide number of promising attempts to evaluate and use of nanoparticles for the control of ticks. The aim of this study was to evaluate the acaricidal activity of zinc oxide nanoparticles (ZnO NPs) size 15 nm against Hyalomma spp. in vitro. The arcaricidal activity of Zn NPs were evaluated at concentrations of 50, 125 and 250 mg/ml and controls (distilled water and Cypermethrin) following 10, 30 and 60 min of exposure in triplicate and the experiments were performed two spraying and contact methods. The results of this study showed that all concentrations of Zn NPs had acaricidal activity and concentration of 125 mg/ml at exposure time of 30 min and concentration of 250 mg/ml at all exposure times had highest acaricidal effect (100%). The median lethal concentration (LC50) values were 50 mg/ml in 60 min and (LC99) values were 150 mg/ml in 30 min for Hyalomma spp.. The results showed that the spray method was more effective than the contact method. The findings of present study showed that Zn NPs had potent acaricidal effect and recommended as an effective acaricidal agent. However, further in vivo studies are required to evaluate the efficacy of this nanoparticle.