Abstract
The development of natural insecticide from plant products may have a beneficial effect as a promising candidate for practical strategies for controlling vector-borne diseases without current treatment. The present study was carried out to characterize green synthesized metallic nanomaterials for silver (Ag-NPs) and gold (Au-NPs) from extract leaf of Nerium oleander L., assess in vivo toxicity, and evaluate the larvicidal activity against Aedes aegypti. The prepared nanomaterials (Ag-NPs and Au-NPs) were characterized by Ultraviolet-Visible Spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and transmission electron microscopy (TEM). In addition, the subacute in vivo toxicity method was used to assess the extract and the nanomaterials (Ag-NPs and Au-NPs); in evaluating larvicidal activities using the World Health Organization (WHO) method. The Ag-NPs and Au-NPs were confirmed by shifting the absorption band in UV-Vis, FTIR spectrums toward higher wavelengths. TEM and XRD analysis were revealed that the average particle size of Au-NPs and Ag-NPs showed 15.30 and 11.48 nm, respectively. In the toxicity experiment, no mortality or signs of toxicity were reported in all groups of treated animals; in larvicidal activity, the Au-NPs and Ag-NPs with LC50 36.0716 and 46.645 ppm respectively showed more effectiveness than leaf extract alone 108.1665 ppm. Collectively, extract leaf of N. oleander L. can be efficiently used to synthesize metallic nanomaterials with silver and gold, which can be adopted as a natural source of insecticide against Ae. aegypti.