Objective: Synthesis of silver nanoparticles (AgNPs) using a simple, cost-effective and environmentally friendly green route approach and to study the antibacterial activity of AgNPs against human pathogens.
Methods:Green route approach is used to synthesize AgNPs using Psidium guajava leaf extract. Fourier transform infrared (FTIR) was used to identify the presence of the functional group. X-ray diffraction (XRD) was used to analyze the structure of prepared AgNPs. Energy dispersive X-ray was used to the characteristic to the composition of the prepared nanoparticles. Size and morphology of the prepared AgNPs were investigated using field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analysis. Antibacterials efficiency of prepared AgNPs was tested against Escherichia coli and Staphylococcus aureus by well diffusion methods.Results: FTIR study shows the presence of different functional groups present in the leaves mediated AgNPs. The XRD studies yield diffraction peaks corresponding to face-centered cubic structure of Ag crystals. Spherical shaped AgNPs with a particle size of about ~55 nm were evidenced using FESEM and TEM analysis. Energy dispersive spectrum of the synthesized AgNPs confirms the presence of silver in the prepared nanoparticles. From UV-VIS analysis it is shown that the absorption band was red-shifted from 430 nm to 456 nm. The prepared AgNPs shows good antibacterial activity against E. coli and S. aureus.Conclusions: P. guajava leaf extract is a potential reducing agent to synthesize AgNPs. The green synthesis approach provides cost-effective and ecofriendly nanoparticles, which could be used in biomedical applications.
Improvement of green route for the synthesis of silver nanoparticles with plant extracts plays a very important role in nanotechnology without any harmful chemicals. The present investigation demonstrates the synthesis of silver nanoparticles by treating silver nitrate with Graviola leaf extract at room temperature.The effect of the extract on the formation of silver nanoparticles was characterized by UV-Vis spectrum, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and Scanning electron microscopic (SEM) analysis. The UV-Vis spectra results show a strong resonance centered on the surface of silvernanoparticles (AgNPs) at 400-450 nm. The Fourier transformation infrared spectroscopy spectral study demonstrates Graviola leaf aqueous extract acted as the reducing and stabilizing agent during the synthesis of silver nanoparticles. XRD and SEM studies revealed that the synthesized silver nanoparticles shows spherical in shape with average particles size around 30-70 nm.
The sol-gel route synthesized LA-NPs were tested for antimicrobial properties against different human pathogenic bacteria and fungi. The test organisms used were clinical isolates viz., Streptococcus pyogenes, Staphylococcus aureus, Escherichia coli, Klebsiella nemoniae and the human fungal pathogens like Candida albicans and Trichoderma viride. The LA- NPs achieved maximum activity against S. aureus compared with other three tested organisms such as S. pyogenes, E. coli and K. pneumonia. It also showed very good antimicrobial properties against studied fungi. At the concentration 1 mg/ml LA-NPs impregnated filter paper disk achieved maximum activity against human pathogen.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.