Abstract: “A facile, rapid and green synthesis of gold and silver nanoparticles (GNPs and SNPs) using juice of different fruits as reducing and stabilizing agent is reported. Seven different fruits were used in the comparative study with green tea and coffee: lemon, melon, pineapple, banana, orange and tomato. The efficiency of the fruits for the synthesis and stabilization of metallic nanoparticles was compared at pH 3, 7 and 10. The effect of the buffer agent, phosphate and HEPES, was also studied. The early analysis of NP formation was done by observing the color change of the samples. Alkaline pH was favorable for the synthesis of metallic NPs at all the tested conditions. Green tea and coffee were the most efficient agents for the synthesis of GNPs and SNPs. The formation of the GNPs was evident only few seconds after the addition of gold salt solution in the extracts. The most efficient fruits for GNP synthesis were lemon, banana and orange. In the presence of these fruits the formation of”

Keywords: metallic nanoparticles, gold nanoparticles, silver nanoparticles, fruit extracts, HEPES buffer, surface plasmon resonance, zeta potential