Investigation of the Larvicidal Potential of Silver Nanoparticles againstCulex quinquefasciatus: A Case of a Ubiquitous Weed as a Useful Bioresource

Abstract

Biosynthesized silver nanoparticles (AgNPs) usingCassia hirsutaaqueous leaf extract were reported in this study. The synthesis was optimized by measuring various parameters such as temperature, time, volume ratio, and concentration. The surface plasmon resonance at 440 nm for 30°C and 420 nm for both 50°C and 70°C measured using the UV-Vis spectrophotometer confirmed the formation of AgNPs synthesized usingC.hirsuta(CAgNPs). The functional groups responsible for the reduction and stabilization of the NPs were identified using Fourier Transform Infrared (FTIR). The morphology, size, and elemental composition of the NPs were obtained using scanning electron microscope (SEM), transmission electron microscope (TEM), and energy dispersive X-ray spectroscopy (EDX). X-ray diffractometer was used to identify the phases and crystallinity of CAgNPs. Crystalline spherical NPs with average diameter of 6.9 ± 0.1 nm were successfully synthesized. The thermal analysis of CAgNPs was observed from DSC-TGA. The larvicidal results against the different larva instar stage ofCulex quinquefasciatusgave LC50= 4.43 ppm and LC90= 8.37 ppm. This is the first study on the synthesis of AgNPs usingC.hirsutaand its application against lymphatic filariasis vector. Hence, it is suggested that theC.hirsutasynthesized AgNPs would be environmentally benign in biological control of mosquito.

Enhanced Antimicrobial, Cytotoxicity, Larvicidal, and Repellence Activities of Brown Algae, Cystoseira crinita-Mediated Green Synthesis of Magnesium Oxide Nanoparticles

“…Similarly, Fouda and coauthors reported the potency of the bio-synthesized MgO-NPs against different pupal and larvae instar of Anopheles stephensi , with LC 50 values at 16.5 μg mL −1 for pupa and 12.5–15.5 μg mL −1 for I–IV larvae instar ( Fouda et al, 2021a ). Adesuji and coworkers reported the larvicidal efficiency of biosynthesized Ag-NPs against different instar larva phases of Culex quinquefasciatus (vector of lymphatic filariasis), recording the LC 50 and LC 90 values of 4.43 and 8.37 μg mL −1 , respectively ( Adesuji et al, 2016 ). In the same context, Ambrosia arborescens leaf extracts and Ag-NPs derived from these extracts proved larvicidal properties against the third-stage larvae of Aedes aegypti mosquitoes (the main vector of Zina, dengue, and chikungunya infections).…”

Biosynthesis of silver nanoparticles mediated by entomopathogenic bacteria: Bacillus cereus VCRC 641 against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus

“…When AgNPs cluster and enter the larval membrane of mosquitoes, they connect to DNA or proteins that contain sulphur, which results in the denaturation of organelles and enzymes. Silver nanoparticles have been demonstrated to affect the larvae of Aedes aegypti and Anopheles stephensi [23,40,41,42].…”

Nanopharmaceuticals as a solution to neglected diseases: Is it possible?

“…Particularly, 5.0 mg/L biogenic nanoparticles made of Agaricus bisporus kill 100% of Culex larvae. Very recently, Murugan et al (2016d), Govindarajan et al (2016) and Adesuji et al (2016) showed the effect of biogenic silver nanoparticles on the filiarasis vector Culex quinquefascius, among othersh. Unfortunately, in all these cases, the silver chloride nanoparticles appeared complexed with silver nanoparticles, and not only silver nanoparticles were acting on the vectors as reported.…”