30 ml of 102 M aqueous solution of silver nitrate was taken in
Erlenmeyer flask and 2.0, 2.5, 3.0 and 3.5 ml of G. superba leaf extract
was added to it separately at room temperature. After 30 min
the solution turns yellow to yellow–red dark brown indicating the
formation of silver nanoparticles. The scheme of green synthesis of
silver nanoparticles is shown in Supplementary material