Synthesis of Silver Nanoparticles Using Callus Extract of Carica papaya - A First Report

This is the first report of synthesis of silver nanoparticles by using callus extract of Carica papaya. MS medium supplemented with the growth hormones, 2.0 mg I-1 IBA and 0.5 mg I-1 BAP was found to be more suitable for the induction of callus and multiple shoots in papaya. The extract of callus obtained by grinding showed ability of synthesis of silver nanoparticles when treated with silver nitrate (1 mM). The formation of brown colour in the reaction mixture indicates the synthesis of silver nanoparticles. The further detection and characterization of these synthesized silver nanoparticles was carried by spectrophotometry. FTIR spectrum analysis showed peaks between 1000-2000 cm(-1) which confirmed the presence of proteins and other ligands required for the synthesis and stabilization of silver nanoparticles. SEM micrograph confirmed the synthesis of spherical silver nanoparticles in the size range of 60-80 nm.