Determination of Essential Factors Affecting Silver Nanoparticle Synthesis using Moringa oleifera Leaves

Abstract

The presence of secondary metabolites in Moringa oleifera is the decisive factor for the green synthesis of silver nanoparticles (AgNPs). Among the metabolites involved in this process, phenols and flavonoids in the plant extract are the two most important groups, acting both as reducing and stabilizing agents. M. oleifera, a well-known herb from Indonesia, was used in this study due to its exceptional properties, such as antioxidant, antimicrobial, and anti-inflammatory among others. The total phenolic content and total flavonoid content in the aqueous extract of M. oleifera leaves were determined, and the values were 62.01 ± 2.05 mg/g and 71.97 ± 0.94 mg/g, respectively. The synthesis factors including pH, extract volume, and temperature for the synthesis of AgNPs were optimized using the onefactor- at-a-time approach. The synthesis experiment showed that a pH of 8.0, an extract volume of 0.3 mL, and a temperature of 80°C resulted in the highest intensity of localized surface plasmon resonance at a wavelength of 419 nm, which favored the synthesis after 24 h of reaction time. Due to the remarkable content of metabolites, M. oleifera can be used as a promising candidate for the effective synthesis of AgNPs.