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The present study is based on optimized green synthesis of silver nanoparticles (AgNPs) using Manilkara zapota fruit extract, formulation of topical gels, and evaluation for their antimicrobial properties. The results reveal that a reaction temperature of 35 °C and a reaction time of 11 h are the optimum conditions to get spherical AgNPs with a particle size of 100.7 nm and a zeta potential of -26.7 mV. The synthesized AgNPs formulated as topical gels demonstrate a broad-spectrum antimicrobial activity against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Aspergillus niger in comparison to the 0.2% (mass fraction) silver nitrate marketed formulation. The AgNPs loaded gels seem promising and could lead to a useful alternative for treating pathogenic infections. [ABSTRACT FROM AUTHOR]

In this study, the synthesis of nanoparticles and their biological evaluation were carried out. A green synthetic approach synthesized silver nanoparticles (AHAgNPs) using an Artocarpus heterophyllus leaf extract. Parameter optimization was performed using Design Expert Ver. 13. The effects of variables like the concentration on the response, particle size, and entrapment efficiency of synthesized AHAgNPs were monitored via analysis of variance. The optimized AgNPs were characterized using ultraviolet-visible spectroscopy and Fourier transform infrared spectroscopy. Scanning electron microscopy and transmission electron microscopy were used to determine the size and shape of nanoparticles. In vitro, antioxidant and antimicrobial potential were determined using standard protocols. The optimized nanoparticles were spherical, with an average 100-110 nm particle diameter. The synthesized nanoparticles showed effective antioxidant, antibacterial, and antifungal activity. In addition, AHAgNPs showed increased biological activities. [ABSTRACT FROM AUTHOR]

This study investigates an efficient and sustainable route of preparing Ag nanoparticles (NPs) using 1-5 mmol/L aqueous silver nitrate with leaf extracts of five plants--Musa balbisiana (banana), Azadiracta indica (neem), Ricinus communis (castor-oil plant), Tridax procumbens (tridax), and Cardiospermum halicacabum (balloon vine) for their wide availability. These synthesized nanoparticles were characterized with the help of ultraviolet (UV)-visible (Vis) spectrophotometer. The peaks were observed in 418-493 nm. For M. balbisiana, A. indica, R. communis, and C. halicacabum, the average size of nanoparticles was in the range of 90-100 nm. For T. procumbens, it was 39-60 nm as determined by dynamic light scattering. Energy dispersive X-ray spectroscopy analysis showed the peak in silver region confirming presence of elemental silver. Field emission scanning electron microscopy showed that the particles were of a spherical shape in M. balbisiana sample with an average size of 33.87 nm as well as in T. procumbents sample with an average size of 28.512 nm. Ag NPs showed effective antibacterial and antifungal activity against representative pathogens of bacteria and fungi. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity of Ag NPs was found to be in the range of 8.9%-78.86%. H2O2 radical scavenging activity was recorded in the range of 6.036%-57.342%. The nanogel was prepared from synthesized Ag NPs, and its properties like viscosity and stability were evaluated. The results confirmed that this protocol is a simple, rapid, one-step, eco-friendly, nontoxic, and alternative conventional physical/chemical method. [ABSTRACT FROM AUTHOR]

In recent years, silver nanoparticles (Ag NPs) had produced by biological methods such as plant extract due to their efficiency, low cost, being non-toxic, and ecofriendly nature. Ag NPs have antibacterial, anti-mold, and anti-fungi because of their high surface area to volume ratio. In this study, Opuntia ficus-indica (Prickly pear) extract was used to produce green synthesized Ag NPs. Different techniques had adopted to describe the generated nanoparticles, such as an ultraviolet spectrophotometer, Transmission Electron Microscopy (TEM), Dynamic Light Scattering (DLS), and Zeta Potential Analysis. Escherichia coli (E. coli), separated from sediment and water of the Hillah River in Babylon city in Iraq, was utilizedto estimate the antibacterial activities of Ag NPs at different concentrations. Both broth microdilution assay and well diffusion assay were applied. The Congo Red Agar implied to investigate the ability of E. coli isolates to form a biofilm. The TEM images of Ag NPs illustrated spherical morphology with a diameter of approximately 22±4 nm. The antibacterial activity tests showed that the Minimum Inhibitory Concentration (MIC) ranged from 0.0125 mg·L-1 to 0.05 mg·L-1, whereas Minimum Bactericidal Concentration (MBC) was from 0.025 mg·L-1 to 0.05 mg·L-1. 5 h of exposure to the 0.025 mg·L-1 concentrations of the Ag NPs had a bactericidal impact on 92% of the E. coli isolates. In our study, we found silver nanoparticles synthesized by Opuntia ficus-Indica have antibacterial activity against waterborne Escherichia coli isolates and it could be utilizedtoreduce microbial growth in contaminated water. [ABSTRACT FROM AUTHOR]

The wide use of metal nanoparticles has raised the concern of their release in the environment and their biological safety. The use of silver nanoparticles (Ag NPs) as effective antimicrobial agent is also questioned due to the resistance developed by pathogens and the biosafety for the host. The genotoxicity caused by such particles need to be assessed to ensure that they are safe to use. In this study, green synthesized Ag NPs were used and the biosafety in terms of genotoxicity was evaluated by in vitro Chromosome aberration (CA) assay using short-term cultures of human peripheral blood. The physicochemical parameters of these Ag NPs were studied for stability in nano form. The transmission electron microscopy (TEM) and energy-dispersive spectroscopy (EDS) were carried out. The dynamic light scattering and zeta potential measurements revealed stable nano particles. The UV visible & fluorescence spectroscopy for binding affinity of Ag NPs did not suggest significant DNA interaction. The exposure of whole blood cultures to Ag NPs for 24 h showed dose dependent increase in frequency of CA per cell at 350, 650 and 1000 µL (P = NS, P < 0.05 and P < 0.001 respectively). Our study demonstrates that genotoxicity of Ag NPs can be reduced by the use of green synthesized Ag NPs at low dose exposure, which will guide selecting right concentrations of NP for further in vivo studies, and future applications. [ABSTRACT FROM AUTHOR]

Eco-friendly synthesis of nanoparticles is an upcoming discipline of nanoscience. Green synthesis of Ag NPs has gained immense importance and much awareness in developed nations. Fascinatingly, such an environmental friendly synthesis of Ag NPs gives a green chemistry-based non-toxic and economical route to nanotechnology. This review article gives insight into the bioinspired synthesis of Ag NPs and mechanisms involved in the synthesis of Ag NPs. In this review, we have summarized the scientific reports in the eco-friendly synthesis arena of Ag NPs and their applications in the biomedical field. Especially, we have focused on plant materials, fungi, algae, and bacterial potential towards the eco-friendly synthesis of Ag NPs. For future perception, there is a need for in silico and in vitro, in vivo research to authenticate the outcomes. [ABSTRACT FROM AUTHOR]

In the present work, we investigated novel, green, and facile approach for the synthesis of stable silver nanoparticles by use of inexpensive and available Iraqi Zahdi palm dates extract as reducing and stabilizing agents. The formation and color change of dark brown suspension of silver nanoparticles were monitored and examined by ultraviolet-visible spectrophotometric analysis at maximum wavelength of 401 nm. The produced nanoparticles were characterized by dynamic light scattering (DLS), Fourier transform-infrared spectrometry (FTIR), atomic force microscope (AFM), X-ray diffraction (XRD) and scanning electron microscopy (SEM)-energy dispersive spectroscopy (EDS). The results demonstrated that particle size distribution was around 90 ± 40 nm which was in line with grain size of the nanoparticles measured by AFM, while the crystallite size was about 20 nm according to the results observed from XRD technique. Additionally, the zeta potential of synthesized silver nanoparticles was found to be nearly about -25 mV, whereby the suspension showed high stability upon storing the sample in a cool place for a long period of time. The synthesized silver nanoparticles exhibited efficient antibacterial activity against pathogenic methicillin-resistant Staphylococcus aureus (MRSA) bacteria. They also showed enhanced anticancer activity against breast cancer cells (MCF7) with high apoptotic effect as compared with normal MCF10A cells, which confirmed the biocompatible nature of green synthesized silver nanoparticles. It is considered that nanosilver particles synthesized with palm dates extract may basically establish a significant step to synthesize such nanoparticles for topical applications as well as an alternative anticancer drug of existing chemotherapeutics of cancer. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) were synthesized through a green chemical approach using the piperine isolated from black pepper. The physicochemical properties of Triton X-100 coated silver nanoparticles (Triton X-100/Ag NPs) were well characterized by ultraviolet-visible absorption spectroscopy (UV-Vis), powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and energy dispersive X-ray spectroscopy (EDS). The TEM images confirmed the spherical shape of silver nanoparticles. The powder X-ray diffraction analysis revealed the silver nanoparticles exhibiting face-centered cubic (fcc) crystal structure with an average crystallite size of 15 nm. The cytotoxicity effects on HepG2 cells were also evaluated with a series of 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay. The effective toxic concentration of Triton X-100/piperine with silver nanoparticles was too low to damage HepG2 cells. The antibacterial activity results showed that the Triton X-100/piperine/AgNPs efficiently inhibited the two bacteria namely S. aureus and E. coli. The Triton X-100/piperine/AgNPs nanoconjugates were effective in inhibiting the growth of both gram-positive and gram-negative bacteria S. aureus and E. coli. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) were synthesized through a green chemical approach using the piperine isolated from black pepper. The physicochemical properties of Triton X-100 coated silver nanoparticles (Triton X-100/Ag NPs) were well characterized by ultraviolet-visible absorption spectroscopy (UV-Vis), powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and energy dispersive X-ray spectroscopy (EDS). The TEM images confirmed the spherical shape of silver nanoparticles. The powder X-ray diffraction analysis revealed the silver nanoparticles exhibiting face-centered cubic (fcc) crystal structure with an average crystallite size of 15 nm. The cytotoxicity effects on HepG2 cells were also evaluated with a series of 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay. The effective toxic concentration of Triton X-100/piperine with silver nanoparticles was too low to damage HepG2 cells. The antibacterial activity results showed that the Triton X-100/piperine/AgNPs efficiently inhibited the two bacteria namely S. aureus and E. coli. The Triton X-100/piperine/AgNPs nanoconjugates were effective in inhibiting the growth of both gram-positive and gram-negative bacteria S. aureus and E. coli. [ABSTRACT FROM AUTHOR]

In this study, an ecofriendly, green method for synthesis of silver nanoparticles (AgNP) has been developed using Mallotus tetracoccus (MT) leaves as a reducing agent. The formation of AgNPs was standardised at pH 7 and 60 °C. UV-visible spectroscopy showed the high peak of absorption band at 420 nm. By atomic force microscopic (AFM) and scanning electron microscopic (SEM) observations, the size of the silver nanoparticles was found to be in the range of 46 to 100 nm, with an average size of 73 nm. The energy dispersive x-ray spectroscopic (EDX ) profile of silver nanoparticles showed typical optical absorption peak approximately at 3 keV. FTIR spectroscopic study revealed that hydroxyl groups of phenols and carboxylic acids were involved in the formation of AgNPs. Through MTT assay, the cytotoxicity results showed that AgNPs were highly effective on human ductal breast carcinoma cell lines (T47D) (76.8 to 84.9%). Thus, the MT-synthesized NPs are said to possess significant anticancer activity on cancer cells and very less toxicity on normal cells, which suggests its further applications in medicine. [ABSTRACT FROM AUTHOR]