Microwave synthesis of copper oxide nanoparticles using tea leaf and coffee powder extracts and its antibacterial activity

Oxides of copper have been investigated for decades due to their unique semiconductor and optical properties. The review of literature revealed that very few reports are available on the synthesis of copper oxide nanoparticles using microorganisms and plant extracts. In this paper, we have reported the synthesis of copper oxide nanoparticles (CuO) using tea leaf and coffee powder extracts under microwave irradiations. The synthesis was carried out by irradiating metal salt and the extracts of tea and coffee in 1:3 ratio in a microwave at 540 W for 7–8 min. The synthesized nanoparticles were characterized by Scanning electron microscope, X-ray diffraction, UV–visible spectroscopy and Fourier transform infrared spectroscopy. The antibacterial activity of these nanoparticles was tested against six human pathogenic microbes. It was interesting to find that these nanoparticles possess remarkable antibacterial activity against two human pathogenic bacteria. Moreover, the use of environmentally benign materials for the synthesis of CuO nanoparticles offers numerous benefits of eco-friendliness and compatibility for pharmaceutical and other biomedical applications. © 2014, The Author(s).