Nanolarvicidal Effect of Green Synthesized Ag-Co Bimetallic Nanoparticles on <i>Culex quinquefasciatus</i> Mosquito

Synthesis of bimetallic nanoparticles has employed many applications especially as larvicidal agents, these bimetallic nanoparticles therefore need to be produced via a cost-effective and eco-friendly route. Here, green synthesis of Ag-Co hybrid nanoparticles obtained from aqueous root extract of palmyra palm was reported. The hybrid nanoparticles formation was noticed by a colour change from light pink to light brown and further studied using UV-Vis and FT-IR spectrophotometers. The maximum absorption wavelength, λmax as determined by the UV-Visible Spectrophotometer was found to be 420 nm. The FT-IR showed the formation and stabilization of the BMNPs. The nanolarvicidal potency was evaluated by the application of varying concentration ranging from 5 to 50 mg/L against first to fourth instars of larvae and recording the percentage mortality after 24 hours. Probit analysis showed the LC50 and LC90 for 1st instar to be 5.237 mg/L and 49.240 mg/L, 9.310 mg/L and 94.969 mg/L for 2nd instar, 13.626 mg/L and 105.542 mg/L for 3rd/4th instars respectively. This result therefore suggests that the nanoparticles can be used as potential control for larval population growth.