Synthesis, characterization and acaricidal activity of green-mediated ZnO nanoparticles against Hyalomma ticks

Abstract

Emerging acaricide resistance in Hyalomma ticks, transmitting wider range of diseases, require eco-friendly and alternative control options. Current study focused on evaluation of ethanolic extracts and Zinc Oxide nanoparticles (ZnO NPs) prepared from neem (Azadirachta indica) and lemon grass (Cymbopogon citratus) Hyalomma ticks, in vitro. UV-vis. spectrometry revealed wavelength of neem mediated ZnO nanoparticles (N-ZnO NPs) and lemon grass mediated ZnO nanoparticles (L-ZnO NPs) to be 374 nm and 377 nm. The XRD patterns showed Bragg's diffraction peaks at 31.8°, 34.4°, 36.2°, 47.5°, 56.5°, 62.8°, 66.4°, 67.9°, 69.0°, 72.5°, 76.9°, 82.1° and 89.2°. Also, the SEM depicted spherical morphology of green ZnO NPs. The in vitro bioassays included Adult immersion test, Adult packet test, larval immersion test, Larval packet test and Egg immersion test. Probit analysis concluded higher mortality in case of N-ZnO NPs than to that of L-ZnO NPs. The adult tick LC50 of N-ZnO NPs and L-ZnO NPs were 4.76 mg/L, 4.92 mg/L compared to LC90 of 8.87 mg/L and 9.1 mg/L. The study reported green ZnO NPs as effective, safer, and eco-friendly candidature against Hyalomma ticks. In vivo model of this study could be adapted against ticks and tick borne diseases from a broader perspective.