2.2. Green synthesis of AgNPs
The synthesis of AgNPs was carried out according to a previous report [20]. A 50 mL of R. ribes extract with a concentration of 0.02 g/mL was poured into a flask containing AgNO3 (100 mL, 0.1 M). For the next step, the reaction mixture was stirred at 40 °C for 24 h. The nanoparticles were formed during the reaction time as brown precipitates. The nanoparticles were washed with water four times and centrifuged at 12000 rpm for 12 min. Afterward, AgNPs were dried at room temperature.