Green synthesis and standardization of biologically synthesized silver nanoparticles

The biological silver nanoparticle was synthesized extracellularly by using Musa balbisiana. The leaf extract has been used as reducing agent in the process of nanoparticles synthesis. In 50 ml leaf extract volume of AgNO3 stock solution was added to make finally the concentration as 1 mM of AgNO3 and allowed to shake in an incubator for several hours in the dark. The changed color was considered as the primary indication of nanoparticles formation. It was indicated that stable and 20-40nm roughly spherical shaped silver nanoparticles was formed. To standardize the nanoparticles biosynthesis different physical parameters like substrate concentration (0–8 mM), pH of range 5 to 12, temperature range of 5 to 500°C, incubation time range of 0 to 120 hrs and salinity of 0.1–1.0% were investigated. It was reported that 4mM AgNO3 conc, pH of 9, temperature 300°C, incubation time 72h and 0.2% salinity were found to be optimum for the synthesis and stability of the silver nanoparticles.