A Novel developments of ZnO/SiO2 nanocomposite: a nanotechnological approach towards insect vector control

Abstract

Recently, there is increasing efforts to develop newer and effective larvicides to control mosquito vectors. This study was carried out to examine the efficacy of ZnO/SiO₂ nanocomposite synthesized using Gum Arabic against Culex quinquefasciatus larvae. The elemental composition, morphology, functional groups and surface plasmon resonance of the ZnO@SiO₂ nanocomposite was analyzed by Energy dispersive X-ray analysis (EDX), Scanning electron microscope (SEM), FTIR and UV-Visible spectroscopy respectively. In bioassay, larvae were exposed to three different concentrations of synthesized ZnO/SiO₂ nanocomposite. The mortality rates at concentrations of 10, 20 and 25 were found to be (70%, 80%, 86%), (56%, 64%, 84%) and (44%, 48%, 76%) for 1^st, 2^nd, and 3^rd instar respectively. This study revealed that the synthesized ZnO@SiO₂ nanocomposite exhibit high larvicidal activity; 1^st instar (LC₅₀=4.024, LC₉₀= 39.273 mg/l), 2^nd instar (LC₅₀=8.767, LC₉₀=51.069 mg/l) and 3^rd instar (LC₅₀=13.761.LC₉₀=81.809 mg/l).