Green synthesis, characterization and larvicidal activity of AgNPs against Culex quinquefasciatus and Aedes aegypti larvae

Abstract

The silver nanoparticles (AgNPs) were synthesized using extracellular metabolites of Streptomyces sp. GRD (JX512257). The characterization of the synthesized AgNPs was performed by UV-VIS spectrophotometer, FT-IR, Scanning Electron Microscopy (SEM) and X-ray diffraction spectroscopy. The synthesised silver nanoparticles have maximum absorption at 450 nm in UV-VIS spectrophotometer. The FTIR data showed prominent peak in 3401.33, 2922.30, 2364.79, 2116.07, 1643.17, 1375.53, 1424.69 and 1324.03 cm-1 ranges. The SEM analysis showed that the AgNPs were spherical and slightly elongated in nature. The XRD peaks revealed the crystalline nature of the silver nanoparticles and the size of the synthesized nanoparticles was found to be in the range of 10-15 nm. The biologically synthesized silver nanoparticles were treated against the mosquito larvae of Culex quinquefasciatus and Aedes aegypti. The LC50 value of synthesized nanoparticle was identified as 1.23 and 1.19 mg L-1 for Culex quinquefasciatus and Aedes aegypti larvae. Further, LC90 values are also identified as 2.97 and 4.93 mg L-1, for Culex quinquefasciatus and Aedes aegypti respectively. Hence the present work suggests that the nanoparticles from Streptomyces sp. GRD would be appropriate for developing a biological control method of mosquito larval population. © 2013 Academic Journals Inc.