Green Synthesis, Characterization and Antimicrobial Properties of Copper Nanoparticles Using Plant Leaf Extracts

Abstract In this study, plant extracts from Ocimum tenuiflorum, Solanum tricobatum, Syzygium cumini, Centella asiatica, and Citrus sinensis are used to create copper nanoparticles (Cu NPs) from a copper nitrate solution in an environmentally friendly manner. Atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and UV–vis spectrophotometry were used to characterize the Cu NPs. Using UV–vis spectrophotometry analysis, the growth and stability of the reduced copper nanoparticles in the colloidal solution were monitored. Scherrer's equation was used to analyze the line width of the refractive peak in the XRD pattern in order to calculate the average diameter of the copper nanoparticles. According to AFM studies, O. tenuiflorum, S. cumini, C. sinensis, S. tricobatum, and C. asiatica formed copper nanoparticles with average diameters of 28 nm, 26.5 nm, 65 nm, 22.3 nm, and 28.4 nm, respectively. Copper nanoparticles were detected by SEM analysis of the stable brown samples; the samples treated with silver nitrate showed the most evenly distributed particles. The well diffusion method was used to assess the silver bio-nanoparticles' antibacterial capabilities against Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus. Interestingly, the copper nanoparticles made from extracts of S. tricobatum and O. tenuiflorum had the strongest antibacterial activity against 30 mm of S. aureus and 30 mm of E. coli, respectively. The Cu NPs generated using this process have potent antibacterial activity against harmful bacteria. Copper nanoparticles are therefore essential to nanotechnology and nanomedicine.