Green synthesis of silica nanoparticles using Enhalus acoroides: characterization and antioxidant activity

Enhalus acoroides is a marine seagrass and belongs to the family Hydrocharitaceae. The current study aims to synthesize of silica nanoparticles using E. acorides as a biological approach and analyze of their antioxidant activity. The characterization techniques were performed by FTIR, XRD, FESEM-EDX, and TGA analysis to find out the physicochemical properties. In addition, antioxidant activity was performed to check the biological activity. FTIR spectral analysis, function groups such as Si–OH stretch, H–O-H stretch, and Si–O-Si bond were observed. The amorphous nature of Si NPs was proved by XRD analysis. FESEM analysis indicated the formation of spherical-shaped Si NPs with an average size of 35.64 nm and EDX analysis confirmed the presence of Si, O, and C. TGA analysis confirmed the thermal stability of E. acoroides-mediated Si NPs. The DPPH assay revealed that 68.03% free radical inhibition activity was found at the concentration of 350 µg/ml. The present investigation concludes the aqueous extract of E. acorides acts as a reducing and capping agent for the synthesis of silica nanoparticles with antioxidant properties. As-produced silica nanoparticles may be useful for the development of new drugs or creams.