scholarly journals Green Synthesis of Silver Nanoparticles using Vitex Negundo Extracts and their Application in the Effluent Treatment of Cracker Industries

2021 ◽  
Vol 2070 (1) ◽  
pp. 012034
Author(s):  
G Kanthimathi ◽  
O Senthilkumar ◽  
C Sankar ◽  
B.S. Prathibha ◽  
S.M. Senthil Kumar

Abstract Silver nanoparticles were prepared by green synthesis, which is an eco-friendly and inexpensive method. The synthesis was carried out using Vitex Negundo leaf extract at room temperature. The nanoparticles were encapsulated with Poly Vinyl Alcohol (PVA) matrix to avoid agglomeration. The formation of silver nanoparticles was confirmed by X-ray Diffraction (XRD). The morphology of the nanoparticles was investigated by scanning electron microscope (SEM). Energy Dispersive X-ray Spectrum (EDX) confirmed the presence of elemental Ag. Adsorption experiments confirmed the removal of toxic cadmium and chromium present in the industrial effluents as analysed by atomic absorption spectroscopy. The silver nanoparticles showed maximum adsorption efficiency for chromium compared to cadmium.

2012 ◽  
Vol 468-471 ◽  
pp. 1974-1977
Author(s):  
Wen Wu ◽  
Dong Sheng Wang

Semi-IPN hydrogels in which silk sericin (SS) chains were physically dispersed throughout dextran (Dex) gel networks were synthesized. Highly stable distributed silver nanoparticles have been prepared using these semi-IPN hydrogels as a carrier via in situ reduction of silver nitrate without the addition of any reducing agent. The resultant semi-IPN hydrogel-silver nanocomposites were characterized by X-ray diffraction (XRD). And the swelling behavior of the hydrogles was also studied.


2021 ◽  
Vol 891 ◽  
pp. 111-115
Author(s):  
Maradhana Agung Marsudi ◽  
Farah Fitria Sari ◽  
Pandu Mauliddin Wicaksono ◽  
Adinda Asmoro ◽  
Arif Basuki ◽  
...  

In this work, silver nanoparticles have been successfully synthesized using simple and environmentally friendly ‘green synthesis’ method using Indonesian wild honey as mediator. Particle count and size can be optimized by varying the silver nitrate precursor and honey concentration, with the help of sodium hydroxide as pH regulator. Based on X-ray diffraction (XRD) result, crystalline structure of Ag has been confirmed in sample with impurities from AgCl. Based on dynamic light scattering (DLS) and transmission electron microscopy (TEM) results, it was found that the smallest average particles size of AgNPs (117.5 nm from DLS and 11.1 nm from TEM) was obtained at sample with 5% w/v of honey and 0.5 mM of AgNO3.


2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Muthusamy Govarthanan ◽  
Min Cho ◽  
Jung-Hee Park ◽  
Jum-Suk Jang ◽  
Young-Joo Yi ◽  
...  

Agroindustrial byproduct mediated green synthesis of silver nanoparticles was carried out using cottonseed oilcake (CSOC) extract. The aqueous silver nitrate formed stable silver nanoparticles with CSOC extract as a reducing agent for Ag+to Ag0. The synthesized nanoparticles were characterized using energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) techniques. The synthesized silver nanoparticles (AgNPs) (4 mM) significantly inhibited the growth of phytopathogens,Pseudomonas syringaepv.actinidiaeandRalstonia solanacearum. Further, cytotoxicity of AgNPs was evaluated using rat splenocyte cells. The splenocyte viability was decreased according to the increasing concentration of AgNPs and 90% of cell death was observed at 100 μg/mL.


2018 ◽  
Vol 27 (1) ◽  
pp. 11-19 ◽  
Author(s):  
Emaad T Bakir Al-Tikrity ◽  
Ibrahim F Waheed ◽  
Sabah M Ali

This work reports the synthesis and characterisation of reduced graphene-1,3,4-oxadiazole-2-thiol (rGS) as a novel nanocompound derivative for graphene. The preparation was performed through a series of reactions starting from graphene oxide, followed by incorporation of different proportions of this nanocompound with poly(vinyl alcohol) (PVA), via non-covalent bonding, to afford the rGS/PVA polymer composites. The pure rGS compound, rGS/PVA composite films and pure PVA film were characterised by different techniques including infrared (Fourier transform infrared) spectroscopy, scanning electron microscopy and powder x-ray diffraction. The electrical properties of the composite films, involving dielectric constant, permittivity ( ε′), imaginary permittivity ( ε″), conductivity (σAC) and loss factor tan δ, were investigated. The measurements were performed at frequencies of (5kHz to 0.5 MHz) at room temperature. At low frequency, the dielectric permittivity ( ε′) and imaginary permittivity ( ε″) attained higher values in all cases, although with increasing frequency these values diminished rapidly. It was also found that the alternating current conductivity of the composites increased with increasing frequency.


2019 ◽  
Vol 22 (6) ◽  
pp. 250-255 ◽  
Author(s):  
Sry Wahyuni ◽  
Syukri Syukri ◽  
Syukri Arief

Studies of green synthesis of nanoparticles mediated by plants extract is extensively explored and studied in recent time due to eco-friendliness, cost-effectiveness, and use a minimum amount of toxic chemicals in the process of inorganic material synthesis. In this study, the immobilization of silver nanoparticles on the surface of titanium dioxide (TiO2) was carried out using Uncaria gambier Roxb. leaf extract as a silver ion (Ag+) reducing agent. The synthesized Ag/TiO2 nanocomposite was characterized by UV-Vis spectroscopy, X-ray diffraction (XRD), and Diffuse Reflectance Spectroscopy (DRS). The formation of silver nanoparticles was confirmed through UV-Vis spectroscopic analysis, which showed a silver surface plasmon resonance (SPR) band at 426 nm. The X-ray diffraction pattern shows that Ag can inhibit the transition of the anatase into rutile phase. The presence of Ag particles in TiO2 can increase the absorption ability from an initial wavelength of 407 nm to 438 nm. Based on the results of Rhodamin B degradation, it can be seen that Ag/TiO2 has a higher photocatalytic activity than bare TiO2 with 99% percent degradation at 120 minutes of irradiation time.


2018 ◽  
Vol 13 ◽  
pp. 117739011878287 ◽  
Author(s):  
Sitaramanjaneya Reddy Guntur ◽  
NS Sampath Kumar ◽  
Manasa M Hegde ◽  
Vijaya R Dirisala

The aim of this study was to perform green synthesis of silver nanoparticles (AgNPs) from the leaf extract of Desmostachya bipinnata (Dharba), a medicinally important herb which is widely used across India. Synthesized AgNPs were analyzed by UV-Visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDAX). The results have confirmed that green synthesis of AgNPs leads to the fabrication of sphere-shaped particles with a diameter of 53 nm. Furthermore, these AgNPs were subjected to antioxidant and antimicrobial studies against gram-negative and gram-positive bacteria, where AgNPs at a concentration of 20 mg/mL showed highest zone of inhibition. Synthesized AgNPs were evaluated for their antioxidant activity by 1, 1-diphenyl-2-picryl hydrazyl radical (DPPH), H2O2, and superoxide inhibiting assays; increasing concentration has showed increase in scavenging ability. Cell toxicity was assessed on HepG2 cell lines, and synthesized nanoparticles at a concentration of 128 μg/mL produced significant reduction in viability of Hep cells ( P < .05). The availability of Dharba throughout the year and the eco-friendly approach in the synthesis of AgNPs coupled with bioactivity has demonstrated its potential as a novel biomaterial which can be used for various biomedical applications.


2021 ◽  
Vol 33 (4) ◽  
pp. 762-766
Author(s):  
BHABANI SHANKAR PANDA ◽  
MOHAMMED ANSAR AHEMAD

The present work concerns on the synthesis of silver nanoparticles at 25 ºC using raw fruits extract of Bakul (Mimusops elengi) tree via chemical reduction route development of poly(vinyl alcohol) PVA-silver polymer nanocomposite films. The nanocomposite films were subjected to characterization by UV-visible, FTIR, X-ray diffraction, field emission scanning electron microscope (FESEM) and thermal studies. The UV-visible spectrum shows a characteristic broad absorption band observed near 465 nm suggesting presence of silver nanoparticles in polymer nanocomposites (PNCs) film. The vibrational band shift of –OH group of poly(vinyl alcohol) in the presence of nanoparticle designated the chemical interaction between –OH group of poly(vinyl alcohol) and silver nanoparticles. The FESEM study confirmed that PVA is not only acted as a capping agent, but also a cross-linking agent. X-ray diffraction study shows that the existence of AgNPs in the poly nanocomposite film and nanoaparticles are crystalline in nature. Thermal studies suggest that the enhanced thermal stability is because of the good packing of the polar crystallites in β-PVA composites as compared to the non-polar α-phase of neat poly(vinyl alcohol) (PVA).


Author(s):  
Subbiah Murugesan ◽  
Sundaresan Bhuvaneswari ◽  
Vajiravelu Sivamurugan

Objective: In the present system, the green synthesis of silver nanoparticles using marine the red alga Spyridia fusiformis and antibacterial activity was carried out.Methods: The seaweed extract was used for the synthesis of AgNPs at room temperature. The silver nanoparticles were characterized by using UV–Visible spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscope and X-ray diffraction (XRD) techniques. The antibacterial activity of biosynthesized silver nanoparticles was carried out by disc diffusion method against pathogenic bacteria.Results: The UV-visible spectroscopy revealed surface plasmon resonance at 450 nm. The FT-IR measurements showed the possible functional groups responsible for the formation of nanoparticles. The X-ray diffraction analysis showed that the particles were crystalline in nature. TEM micrograph has shown the formation of silver nanoparticles with the size in the range of 5–50 nm. The silver nanoparticles synthesized from the S. fusiformis showed higher activity and proved their efficacy in controlling the pathogenic bacterial strains. The nanoparticles showed highest inhibition activity on K. pneumaniae and S. aureus up to 26 and 24±0.01 mm at 100 μg/ml of nanoparticles.Conclusion: The synthesised AgNPs have shown the best antibacterial activity against human pathogens E. coli, K. pneumoniae, S. aureus and P. aeruginosa. The above eco-friendly AgNPs synthesis procedure could be a viable solution for industrial applications in the future and therapeutic needs.


2020 ◽  
Vol 21 (2) ◽  
pp. 173
Author(s):  
Nur Aifah Tun Nisa ◽  
Diana Eka Pratiwi ◽  
Maryono Maryono

Telah dilakukan penelitian tentang sintesis nanopartikel perak menggunakan bioreduktor ekstrak daun kelor (Moringa oleifera) yang berperan sebagai agen pereduksi. Penelitian ini bertujuan untuk menentukan pengaruh penambahan PVA terhadap karakteristik nanopartikel perak yang terbentuk dengan menggunakan ekstrak daun kelor (Moringa oleifera). Nanopartikel perak disintesis dengan variasi konsentrasi PVA yang berbeda-beda yaitu 0%, 1%, 3% dan 5%. Proses pembentukan nanopartikel perak dimonitoring dengan menggunakan spektrofotometer UV-Vis. Hasil penelitian menunjukkan bahwa nilai absorbansi meningkat dengan bertambahnya waktu reaksi dimana PVA digunakan untuk menstabilkan ukuran nanopartikel perak sehingga mencegah aglomerasi pada pembentukan nanopartikel perak. Serapan maksimum UV-Vis dari sampel hasil sintesis dengan variasi konsentrasi PVA yaitu 0%, 1%, 3% dan 5% masing-masing pada panjang gelombang 432,1 nm, 431,0 nm, 502,0 nm, dan 409,0 nm selama penyimpanan 2 hari. Ukuran nanopartikel perak ditentukan menggunakan instrumen X-Ray Diffraction (XRD) dengan persamaan Debye Scherrer. Distribusi rata-rata ukuran sintesis nanopartikel perak tanpa penambahan PVA yaitu 13,24 - 22,53 nm sedangkan dengan penambahan PVA ukuran terkecil nanopartikel perak mencapai 11,61 - 15,40 nm pada konsentrasi PVA 5%. Berdasarkan database ICDD, hasil analisis XRD menunjukkan adanya kesesuaian pola difraksi dengan referensi sehingga dapat disimpulkan pada penelitian ini terbentuk nanopartikel perak dengan sistem kristal kubik fcc (Face Centered Cubic) dengan indeks Miller (111), (200), (220), dan (311). Morfologi nanopartikel perak diamati dengan Scanning Electron Microscopy (SEM), terlihat partikel tidak memiliki pori dan bentuk partikel yang tidak seragam. Kata kunci: Ekstrak daun kelor, nanopartikel perak, bioreduksi, dan Poli Vinil Alkohol ABSTRACT The research was conducted to synthesize of silver nanoparticle using bioreductor of Moringa Oleifera leave extract (Moringa oleifera) as a reducing agent. This study aims to determine the effect of addition of PVA to the characteristics of silver nanoparticles formed using Moringa Oleifera leave extract (Moringa oleifera). Silver nanoparticles was synthesized with varying concentrations of PVA namely 0%, 1%, 3% and 5%. The process of forming silver nanoparticles was monitored by using a UV-Vis spectrophotometer. The results showed that the absorbance value increased with increasing reaction time where PVA was used to stabilize the size of silver nanoparticles so as to preventing agglomeration in the formation of silver nanoparticles. The maximum UV-Vis uptake of the synthesize samples with variation PVA is 0%, 1%, 3% and 5% respectly at wavelengths of 432.1 nm, 431.0 nm, 502.0 nm, and 409.0 nm for 2 days of storage. The size of silver nanoparticles was determined using X-Ray Diffraction (XRD) with the Debye Scherrer equation. The average distribution of the size of silver nanoparticles synthesis without the addition of PVA is 13,24 – 22,53 nm while with the addition of PVA the smallest size of silver nanoparticles reaches 11,61 – 15,40 nm at a 5% PVA concentration. Based on the ICDD database, the results of the XRD analysis indicate that there is a suitability of the diffraction pattern with reference so that it can be concluded that this study formed silver nanoparticles with a fcc (Face Centered Cubic) crystalline system with the Miller index (111), (200), (220), and (311). The morphology of silver nanoparticles was observed by Scanning Electron Microscope (SEM). It was seen that the particles did not have pores and the shape of the particles was not uniform. Keywords: Moringa leaves extract, silver nanoparticles, bioreduction, and Poly Vinyl Alcohol


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