Synthesis and Characterization of ZnO@SiO2 Nanocomposite using Gum Arabic and its Larvicidal Activity on Malaria Vectors

Green synthesis of ZnO@SiO2 nanocomposite was performed using Gum Arabic. The green synthesized nanocomposite was characterized using Fourier Transform Infrared Spectrophotometer (FTIR), The Scanning Electron Microscopy (SEM), UV-Visible spectrophotometer, Dynamic Light Scattering (DLS), and X-Ray Fluorescence (XRF). The toxicity study was conducted for 24 hours on 1st to 4th larval instars of malaria vectors at various concentrations (10, 20 and 25 mg/L). The LC50 and LC90 for the 1st - 4th larval instars were found to be in the range of 9.11 - 18.288 mg/L and 157.254 - 126.132 mg/L respectively. A strong positive correlation between concentrations of the nanocomposite and mortality of larval instars (0.945 - 0.997). These values indicate that the mortality rates increased with an increase in concentrations. ZnO@SiO2 nanocomposite is a potential nano-larvicide for malaria vector control in tropical countries with high malaria incidence.