Facile and Green Route to Silver Nanoparticles Using Aqueous Plant Extract, and their Photocatalytic and Antibacterial Studies

Abstract

Silver nanoparticles were prepared through an environmental friendly and cost-effective plant-mediated technique, using crude extracts of Welsh onion plant. The synthesized nanoparticles were characterized using UV-vis spectrophotometer, powdered X-ray diffractometer (p-XRD), Fourier transform infra-red (FTIR) spectrophotometer, and transmission electron microscope (TEM). Silver nanoparticles of different sizes and morphologies were obtained by varying some synthesis parameters such as concentrations of AgNO3 (1, 2 and 5 mM) and ratio of the volume of the plant extract to AgNO3 (1:5 and 1:10) at constant reaction temperature of 80 °C. The difference in the reaction conditions showed significant effects on silver nanoparticles obtained. The surface plasmon resonance (SPR) varied with change in concentration of AgNO3 and the ratio of the AgNO3 to the plant extracts. The lowest SPR appeared around 412 nm (2 mM; 1:10), while the largest was achieved around 427 nm (5 mM; 1:10). FTIR results revealed the presence of different characteristic functional groups responsible for the bioreduction of silver ions in Welsh onion extract. Transmission electron microscopy (TEM) showed that the lowest average particle size of the silver nanoparticles was 3.74 nm (2 mM; 1:10), while the highest was 15.72 nm (1 mM; 1:5). Monodispersed spherical shaped nanoparticles were obtained from the 2 mM concentration of the AgNO3, while particles with some degree of agglomeration were obtained from 1 and 5 mM concentration. The p-XRD studies revealed face centred cubic structures. The nanoparticles obtained from 1 and 5 mM (1:5) gave moderate photo-catalytic potentials in the degradation of methyl red dye. However, the photocatalytic property increased with increase in the concentration of the precursor salt (AgNO3) from 1 to 5 mM. Gram positive Staphylococcus aureus and Bacillus cereus and Gram negative Klebsiela pneumonia and Escherichia coli bacteria strains were susceptible to the silver nanoparticles (2 mM). The nanoparticles were most active against E. coli with a minimum inhibitory concentration (MIC) below 0.05 mg/mL. The silver nanoparticles could become potential compounds in the future antibiotic research.

Green Synthesised Silver Nanoparticles Using Anoectochilus elatus Leaf Extract: Characterisation and Evaluation of Antioxidant, Anti-Inflammatory, Antidiabetic, and Antimicrobial Activities

“…Moreover, green synthesis methods ensure the production of nanoparticles with welldefined shapes, sizes, and surface charges, enhancing their antimicrobial effectiveness [52]. Using natural reducing agents from plants or microorganisms can introduce additional antimicrobial compounds into the synthesis process, synergistically enhancing the overall antimicrobial activity of the nanoparticles [53]. A recent study reported varying inhibition zone diameters resulting from the antimicrobial activity of AgNPs against different bacteria.…”

Green Synthesized Silver Nanoparticles: A Potential Antibacterial Agent, Antioxidant, and Colorimetric Nanoprobe for the Detection of Hg2+ Ions

“…Hence, it is essential to investigate plant extracts that include biomolecules that have inherent antibacterial activity in order to synthesize AgNPs with a rational antibacterial activity. [2,3,25,30,[47][48][49][50][51][52] A well-known hazardous element that has detrimental effects on both human health and the environment is mercury (Hg). Hg 2+ ions have been widely detected using a variety of sensing techniques, such as atomic absorption spectrometry (AAS), atomic emission spectrometry (AES), and inductively coupled plasma mass spectrometry (ICP-MS).…”

“…Hence, it is essential to investigate plant extracts that include biomolecules that have inherent antibacterial activity in order to synthesize AgNPs with a rational antibacterial activity. [ 2 , 3 , 25 , 30 , 47 , 48 , 49 , 50 , 51 , 52 ]…”

Electrocatalytic activity of metal encapsulated, doped, and engineered fullerene-based nanostructured materials towards hydrogen evolution reaction

“…Jun Xing et al 5 studied the active sites on hydrogen evolution photocatalyst and reported through a combined experimental approach, that metallic Pt nanoparticles have little contribution to the activity of photocatalytic H 2 evolution; the oxidized Pt species embedded on the TiO 2 surface are the key active sites and primarily responsible for the activity of the hydrogen evolution Pt/TiO 2 photocatalyst. DFT approach was also employed by Puente et al 12 , 13 in the scientific area of “Tailoring the interfacial interactions of van der Waals 1T-MoS 2 /C 60 Heterostructures for High-Performance Hydrogen Evolution Reaction Electrocatalysis and their result showed that the heterostructure domains of 1 T-MoS 2 and C 60 NSs exhibited excellent hydrogen evolution reaction (HER) performances, with one of the lowest onset potentials and ΔGH* values for LD non-precious nanomaterials. In furtherance, Lin et al, proposed alloying noble and non-noble metals as promising catalyst for HER.…”