Manifestation of solvents induced self-assembly of green synthesized CuO nanostructures and their enhanced antimicrobial activities

Green synthesis of CuO nanospindles and their assembly into nanoflowers has been demonstrated by changing the solvents such as water and ethanol along with the Dodonaea angustifolia (DA) extract. This is the first to report the use of DA extract for the green synthesis of nanostructures. The DA+water yielded the nanospindles of CuO, while DA+ethanol led to the assembly of nanospindles into nanoflowers as confirmed from their electron microscopy images. The Fourier-transform infrared spectrum of the extract and CuO revealed that the DA led to the phase formation and capped the CuO nanostructures. The antimicrobial activity against E. coli and S. aureus bacteria was found to be enhanced for CuO nanoflowers as compared to nanospindles. Based on the results, the mechanism for the formation and anti-microbial activity of the CuO nanostructures have been proposed.