GREEN SYNTHESIS OF SILVER NANOPARTICLES USING MORINGA OLEIFERA, EMPLOYING MULTIVARIATE OPTIMIZATION METHODOLOGIES

Multivariate optimization was employed in the synthesis of silver nanoparticles (AgNPs) using a greener approach. The flowers, leaves and stem bark water extracts of Moringa oleifera were reacted with silver nitrate solution to form the silver nanoparticles. Four factors namely; extraction time, extraction volume, reaction time and reaction temperature were optimized simultaneously with absorption via ultraviolet ? visible (UV-VIS) spectrometry used to follow the optimization, i.e., the response. The results showed that there were some interaction factors and as well as curvature that contributed significantly to the response. The silver nanoparticles (AgNPs) showed ultraviolet visible (UV-Vis) absorption peaks at 415, 426 and 420 nm for AgNPs synthesized from the flowers, leaves and stem bark water extracts, respectively. The three different plant parts of Moringa oleifera also produced AgNPs of a spherical shape as observed through a scanning electron microscope (SEM). The average sizes of AgNPs obtained when using the flowers, leaves and stem bark extracts were 273. 98 nm, 96.72 nm and 95.12 nm, respectively. The stem bark extract produced better NPs in terms of uniform dispersity (mono-dispersed), while the flowers and leaves produced poly-dispersed NPs.