Rapid Biosynthesis Method and Characterization of Silver Nanoparticles Using Zizyphus spina christi Leaf Extract and Their Antibacterial Efficacy in Therapeutic Application

Abstract

Antibacterial activity of biosynthesized silver nanoparticles (AgNPs) was significant in therapeutic application of nanotechnology. These researchers studied an ecofriendly and rapid method for the first time to synthesize silver nanoparticles using Zizyphus spina christi L aqueous leaves extract (ZSE), and their antibacterial properties. The extract was found to have the potential to form silver nanoparticles at room temperature within few minutes. The green synthesized silver nanoparticles were characterized using different techniques. The UV-visible spectrum of the solution containing AgNPs showed a peak at 414 nm corresponding to the plasmon absorbance of silver nanoparticles. The transmission electron microscopy (TEM) showed that the formed particles were hexagonal in shape with appreciable Nano size ranging from 21.5 to 59.67 nm. Fourier Transform Infrared Spectroscopy analysis (FTIR) of biosynthesized AgNPs affirmed the role of ZSE as reducing and capping agent of Ag+ ions to AgNPs, and X-Ray Diffraction patterns (XRD) showed that they could be indexed as face-centered-cubic structure of silver. Antibacterial activity of AgNPs was determined by well diffusion and micro plate assay methods, showing maximum inhibition zones of 24 mm, 23 mm, 15 mm and 17 mm against Staphylococcus aureus, Acinetobacter sp., Pseudomonas aeruginosa and Escherichia coli respectively. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) results showed that AgNPs had MIC, MBC of 45, 57 μg/mL, 49, 61 μg/mL, 63, 90 μg/mL and 59, 82 μg/mL against S. aureus, Acinetobacter sp., P. aeruginosa and E. coli respectively. Furthermore, the green synthesized AgNPs were loaded on band-aids and screened for antibacterial activity. The AgNPs loaded on band-aids exhibited strong antibacterial effect against multi drug resistant bacteria. These nanoparticles could be used for treating wounds and preparing wound dressing. Such researches are crucial in the demonstration of therapeutic importance of silver nanoparticles in medical application.