Green chemistry approach for the synthesis of gold nanoparticles with gum kondagogu: characterization, catalytic and antibacterial activity

Gold nanoparticles (AuNPs) were prepared from HAuCl4 using gum kondagogu, by adopting green synthesis, which is a simple, low cost and ecofriendly technique. The gum kondagogu (Cochlospermum gossypium) serves as both reducing agent and stabilizer. The formation of the AuNPs was identified through the change in the color of the solution from yellow to red. The synthesized AuNPs were characterized by various techniques. The green synthesized AuNPs were found to be stable in the pH range pH 2-12 and up to the concentration of 5 M NaCl. The stabilized AuNPs demonstrated the excellent catalytic activity in reducing p- nitrophenol to p-aminophenol in the presence of a reducing agent, NaBH4. The effects of catalyst dose and temperature were studied. The synthesized, new gum-based catalyst was very efficient, easy to prepare, stable, cost-effective and ecofriendly. The synthesized AuNPs showed good antibacterial activity.