Murraya koenegii Spreng. Leaf Extract: An Efficient Green Multifunctional Agent for the Controlled Synthesis of Au Nanoparticles

There is a demand for the development of reliable, cost-effective, and environment friendly protocols for the synthesis of metal NPs with finely tuned structures for technological applications. In the present work, we have exploited the antioxidant activity of the aqueous extract of dried and pulverized leaves of Murraya koenigii Spreng. as a green multifunctional agent in the synthesis of Au NPs with finely tuned morphologies, and our method is a promising green tool for the synthesis of Au NPs with tailor-made structural properties. Moreover, the uniqueness of the present biogenic synthetic route is that simple experimental parameters like control of the concentration of the multifunctional agent and precursor metal ion and also pH and temperature can be effective in the synthesis of Au NPs with finely tuned structures. We have also proposed a plausible mechanistic pathway for our green synthetic route, which may aid in fine-tuning green chemical methods for the controlled synthesis of various metal NPs. At the same time, our study on the interaction between Au NPs and surface-adsorbed fluorescent groups may also be helpful for physicochemical investigations on energy transfer and near-field optical enhancement. Thus, this type of study may be explored in the future for fabricating novel photonic devices.