“…The synthesis of AgNPs was monitored and optimized by recording the UV-Vis spectra of the reaction mixtures in the wavelength range of 350–800 nm [ 29 , 33 , 34 , 35 , 36 ] on a Specord 210 Plus spectrophotometer (Analytik Jena, Jena, Thuringia, Germany). In order to obtain the maximum yield of AgNPs, the synthesis was conducted at various parameters such as pH value of the reaction mixture (2, 4, 6, 8, and 10), AgNO 3 concentration (0.5, 1, 2, and 3 mM), ratio of aqueous bark extract and AgNO 3 (1:9, 2:8, 5:5, 7:3, and 9:1, v / v ), temperature (30, 40, 50, 60, 70, and 80 °C), and reaction time (10, 20, 30, 60, and 120 min).…”