Aqueous phase lavender leaf mediated green synthesis of gold nanoparticles and evaluation of its antioxidant activity

Abstract

In this paper, green synthesis of gold nanoparticles (AuNPs) using leaf extract of Lavender (Lavandula angustifolia) and their antioxidant activity was evaluated under the ambient aqueous phase condition. Assynthesized AuNPs were characterized by visual, ultraviolet-visible-near infrared (UV-vis-NIR) spectroscopy, transmission electron microscopy (TEM), and dynamic light scattering (DLS) technique. Formation of AuNPs produces an intense absorbance peak at 530 and 1055 nm in UV-visible spectroscopy. TEM and DLS results confirmed that the synthesized AuNPs were crystalline, polydisperse, quasi-spherical and triangular shape with an average size ranging from 34-300 nm. UV-vis-NIR, TEM, and DLS study showed that the phytochemicals from the Lavender leaf extract have dual properties of reducing and stabilizing agents. Further, AuNPs (21.53%, 0.2 mL) showed higher antioxidant activity than Lavender leaf extract (4.73%, 0.2 mL) against 2,2-diphenyl-1-picrylhydrazyl. On looking these advantages, green synthesis of AuNPs without inert atmosphere is highly recommended for future medicinal and industrial application.