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

Prasanta Sutradhar,Debasish Maiti,Mitali Saha

doi:10.1007/s40097-014-0086-1

Abstract

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.

Highlights

The development of rapid and reliable processes for the preparation of nanosized metal particles has attracted significant attention due to their unusual size-dependent optical and electronic properties
We have reported the synthesis of copper oxide nanoparticles (CuO) using tea leaf and coffee powder extracts under microwave irradiations
In continuation of our earlier efforts for the synthesis of new carbon and metal nanoparticles for their applications in different fields [24,25,26,27], we have reported the synthesis of nanosized copper oxide (CuO) via a green route, using tea leaf and coffee powder extracts

Summary

Introduction

The development of rapid and reliable processes for the preparation of nanosized metal particles has attracted significant attention due to their unusual size-dependent optical and electronic properties. A large number of physical, chemical and biological methods were available to synthesize different types of nanoparticles [1,2,3,4]. Different methods have been available in the literature for the preparation of copper oxide nanoparticles, where flammable or corrosive reducing agent has been used such as titanium tetrachloride and hydrazine. In continuation of our earlier efforts for the synthesis of new carbon and metal nanoparticles for their applications in different fields [24,25,26,27], we have reported the synthesis of nanosized copper oxide (CuO) via a green route, using tea leaf and coffee powder extracts. The exact mechanism for the synthesis of nanoparticles using plant extracts has not been devised, but it was suggested that different polyol

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Results and discussion

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