Mosquito larvicidal activity of silver nanoparticles synthesized using Azolla pinnata against Culex quinquefasciatus Say (Diptera: Culicidae)
Jeyaraj John Wilson, Shunmugiah Mahendran, T. Sivakumar, Ponnirul Ponmanickam, Ramasundaram Thangaraj
Abstract
Vector control is a significant component of interventions to control mosquito-borne diseases. In the present study, silver nanoparticles (Ag NPs) were synthesised using the seaweed Azolla pinnata to evaluate larvicidal activity against Culex quinquefasciatus. The biosynthesis of Ag NPs using Azolla pinnata extract was confirmed by the visible change in colour of the reaction mixture from light green to brown. UV–Vis spectra analysis showed that absorbence peaks at around 254 nm due to the surface Plasmon resonance of the silver nanoparticles. The analytical studies of SEM, EDX, FTIR, and XRD analysis results supported the confirmation of Ag NPs. Synthesized Ag NPs were assessed for the mortality rate of Culex quinquefasciatus. Based on LC50 and LC90 analysis, 4.287μl/ml of Ag NP is required to kill 50% of the larvae, whereas 10.795μl/ml is necessary to kill 90% of the larvae. Moreover, the synthesised Ag NPs exhibit high bioactivity on mosquito larvae and can thus be utilised as a biological control agent to control mosquito populations.