Evaluation of Antioxidant Activity and Bioefficacy of Encapsulated Silver Nanoparticles Against Aedes aegypti

Abstract

Present research highlights the biofabrication of encapsulated silver nanoparticles (AgNPs) using phyto-extracts as reducing, capping and stabilizing agents as a novel tool against Aedes aegypti, the primary vector of dengue. For ensuring their stability, antioxidant activity was studied through DPPH scavenging assay and Nitric Oxide (NO) scavenging assay, while for safer development of encapsulated silver nanoparticles toxicity assessment was conducted in human embryonic kidney cell lines (HEK 293) as a non-target model. newlineIn the first phase, synthesis and characterization of twelve different nanoparticles (Musa acuminate, Carica papaya, Trigonellafoenum graecum, Trachyspermum ammi and their combinations), nanoemulsions (ajwain oil and lemongrass oil) and encapsulated nanoparticles (ENP-I, ENP-II, ENP-III and ENP-IV) was done and characterized through UV-Vis spectrophotometry, FESEM, HRTEM, FTIR, DLS, and XRD analysis. Smallest silver nanoparticles were synthesized with combinational phyto-extracts indicating that they were effective in reducing the size of nanoparticles synergistically in comparison to individual extracts. The size of encapsulated silver nanoparticles ranged from 53.25nm to 89.66nm. Further, the systematic study done presently, clearly indicates that antioxidant activity is not dependent on the particle size and a gradual enhancement in the activity from green synthesized AgNPs to nanoemulsions and finally their encapsulations was recorded. newlineThe overall larvicidal studies indicated that all twelve AgNPs and their encapsulations acted as effective larvicidal agents and the order of their effectiveness is as follows: ENP-IIgt ENP-Igt ENP-IIIgt ENP-IVgt AJ-NEgt LG-NEgt P+B-AgNPsgt AJ+FG-AgNPsgt AJ-AgNPsgt P-AgNPsgt FG-AgNPsgt B-AgNPs. While risk assessment studies further proved the non-toxic nature of these encapsulated silver nanoparticles. This study validated the synthesis of biocompatible encapsulated silver nanoparticles with enhanced mosquito larvicidal activity against Aedes aegypti and least toxicity against HEK 293 mammalian cell lines proving them to be an effective and ecofriendly alternative for managing mosquito borne diseases. newline newline