Background: Plant synthesized silver nanoparticles give rapid control on mosquito larvae of
dengue vector, Aedes albopictus. AgNPs synthesized from the plant, Argemone mexicana for the control of
larvae and these nanoparticles inhibit the growth of microbes are broad spectrum of nanoparticle activities.
Methods: Nanoparticles were subjected to analysis by UV-vis spectrophotometry, Fourier transform infrared
spectroscopy, scanning electron microscopy and transmission electron microscopy. Furthermore,
laboratory evaluation of plant mediated nano-particle carried out lethal toxicity on Aedes albopictus.
The characterization studies confirmed the spherical shape and size (5-50 nm) of silver nano-particles.
Results: The efficacy of AgNPs was tested at concentration of 2 to 10 ppm against L1 to L4 larval instar
of A. albopictus. The LC50 followed by LC90 values were (L1) 5.24, 8.66; (L2) 5.56, 8.85; (L3) 6.20,
10.01 and (L4) 7.04, 10.92 at 10 ppm of silver nanoparticle, whereas LC50 (LC90) values of (L1) 7.63,
11.58; (L2) 8.17, 11.88; 8.80, 12.82 and 8.94, 12.26 at 10 ppm of plant extract alone treated larvae, respectively.
The mortality rates were positively correlated with the concentration of AgNPs. Significant
(P<0.05) high square value changes in the larval mortality were also recorded between the period of exposure
against all larval instar of A. albopictus. Silver nanoparticles were also tested for antimicrobial
activity and significant toxicity inhibition was observed against the gram positive microbes and it exhibited
mild toxicity against P. aeroginosa.
Conclusion: Plant, A. mexicana synthesized silver nano-particles are rapid and potential mosquito larvicidal
as well as antimicrobial agents. Finding of our results support that silver nanoparticles can be prepared in a
simple and cost-effective manner and are suitable for bio-formulation against mosquitoes and microbes.