Shahryar Pashaei; Samaneh Safari; Soleyman Hosseinzadeh
Abstract
In the present study, synthesis of silver nanoparticles and its antibacterial activity were investigated. Silver nanoparticles were rapidly synthesized using leaf extract of beet sugar leaf the formation of nanoparticles was observed within 1 hr. The results recorded from UV–vis spectrum, Transmission ...
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In the present study, synthesis of silver nanoparticles and its antibacterial activity were investigated. Silver nanoparticles were rapidly synthesized using leaf extract of beet sugar leaf the formation of nanoparticles was observed within 1 hr. The results recorded from UV–vis spectrum, Transmission electron microscopy (TEM) and X-ray diffraction (XRD) support the biosynthesis and characterization of silver nanoparticles. The UV-Visible spectrophotometer was indicated absorbance peak in range of 435-440 nm. From high resolution transmission electron microscopy (HRTEM) analysis, the size of the silver nanoparticles was measured 35–40nm. Further, the antibacterial activity of synthesized silver nanoparticles showed effective inhibitory. It showed that antibacterial activity increased by addition concentration of silver nano particle. The 0.008 molar concentrations of AgNPs, antibacterial activity was higher than other concentrations. Results confirmed this protocol as simple, rapid, one step, and eco-friendly, nontoxic and alternative conventional physical/chemical methods. Nanoparticle synthesis is a novel research are to search for an eco-friendly manner and green materials for potential applications in the fields of medicine and drug delivery.
Soghra Fathalipour; Sima Pourbeyram; Sanaz Lotfi; Rasul Bulgar
Abstract
Silver nanoparticles (Ag NPs)-reduced graphene oxide was prepared through the in situ nucleation of Ag NPs on reduced, modified GO (rMGO). Glycine was used as a green reducing as well as modifier agent for GO to obtain rMGO. Nucleation of Ag NPs on rMGO was carried out at 80 ◦C at aqueous media. UV-Vis, ...
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Silver nanoparticles (Ag NPs)-reduced graphene oxide was prepared through the in situ nucleation of Ag NPs on reduced, modified GO (rMGO). Glycine was used as a green reducing as well as modifier agent for GO to obtain rMGO. Nucleation of Ag NPs on rMGO was carried out at 80 ◦C at aqueous media. UV-Vis, FT-IR, and XRD techniques confirmed the reduction, modification, and synthesis of Ag NPs. Meanwhile, the morphology of rMGO and rMGO-Ag nanocomposite was investigated with SEM and TEM images. The synthesized nanocomposite showed excellent catalytic behavior for the reduction of 4-nitrophenol (4-NP) by NaBH4. The electrocatalytic behavior of Ag NPs on rMGO for electroreduction of H2O2 was investigated by cyclic voltammetry (CV). In the optimum condition, H2O2 was determined with a detection limit of 9.4 µM and sensitivity of 0.52 µAµM-1. In addition, with the investigation of MIC data of nanocomposite, it was distinguished that this compound has excellent antibacterial activity.
Tahereh Rohani; Moghadase Yahyapoor
Volume 4, Issue 1 , March 2017, , Pages 34-39
Abstract
In this work, a new method was developed for the catalytic reduction of hydrogen peroxide at glassy carbon electrode modified with silver nanoparticles and multi-wall carbon nanotubes. Silver incorporated in this modified electrode acted as catalyst to reduce hydrogen peroxide. First, the electrochemical ...
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In this work, a new method was developed for the catalytic reduction of hydrogen peroxide at glassy carbon electrode modified with silver nanoparticles and multi-wall carbon nanotubes. Silver incorporated in this modified electrode acted as catalyst to reduce hydrogen peroxide. First, the electrochemical behavior of silver, incorporated in modified electrode, was studied. The results illustrated the adsorption-controlled reaction at the modified electrode. Then, the behavior of catalytic reduction of hydrogen peroxide at the modified electrode was investigated. A linear calibration graph was obtained for hydrogen peroxide over the concentration range of 4.04×10−3 – 1.5×10−6 molL-1. The detection limit for hydrogen peroxide was estimated 1.42×10−7 molL-1. The relative standard deviation of ten replicate measurements (performed on a single electrode at hydrogen peroxide concentration of 1.5×10-4 molL−1) was 2.36%. The proposed electrode was used for the determination of hydrogen peroxide in real samples which led to satisfactory results.