Chemical synthesis of silver nanoparticles
About 10 ml of 1.0 mM silver nitrate was added drop wise (about one drop/sec) to 30 ml of 2.0 mM solution of sodium borohydride. The reaction mixture was stirred vigorously on a magnetic stirrer plate. The solution was turned light yellow after the addition of 2 ml of silver nitrate and brighter yellow when all of the silver nitrate had been added. After which the stirring was stopped and the stirrer bar was removed. The presence of silver nanoparticles can be identified by color change.