Biogenic ZnO Nanoparticles from Sage Extract

The aqueous extract derived from the leaves of S. officinalis was employed in the reduction of Zinc nitrate hexahydrate solution for the biopreparation of ZnO-NPs. Zinc nitrate hexahydrate (Zn (NO₃)₂·6H₂O) with a purity of 98% was obtained from Sigma-Aldrich, located in Poole, Dorset, U.K. Five milliliters of S. officinalis leaf extract was added to 95 mL of a solution of 0.01 M Zinc nitrate hexahydrate. Subsequently, the flask was subjected to magnetic stirring for 60 min at 70 °C. The formation of reduced precipitates is indicative of the formation of ZnO-NPs. The reaction mixture was then centrifuged at 10,000 rpm for 10 min for the separation of the reduced precipitates. In order to eliminate any extract residues, the precipitates were subsequently washed with distilled H₂O. Finally, the precipitates were incubated in an oven for 8 h at 100 °C for subsequent physicochemical characterization [40 (link)].