scholarly journals Effect of Different Process Parameters on the formation of Silver Nanoparticles using Crude and Modified Neem (Azadirachta indica) Leaf Extracts

2021 ◽  
Vol 1 (2) ◽  
Author(s):  
Kalaivani Vivehananthan ◽  
◽  
W.H. De Silva
Keyword(s):  
Silver Nanoparticles ◽  
Process Parameters ◽  
Leaf Extract ◽  
Visible Range ◽  
Mixing Ratio ◽  
Visible Spectroscopy ◽  
Leaf Extracts ◽  
Maximum Absorbance ◽  
Uv Visible ◽  
Neem Leaf Extract

In recent times, the biosynthesis of nanoparticles, which has led to significant growth in the field of nanotechnology. The use of plant extracts has become an impetus in this field as it is a simple and eco-friendly method. This study was an attempt to study different parameters in biosynthesis of silver nanoparticles using Azadirachta indica (Neem) leaf extracts. Four different process parameters such as concentrations of neem leaf extract, types of neem leaf extract, mixing ratios and the reaction time period were investigated on the formation of silver nanoparticles. Initially, the formation of silver nanoparticles was detected by the visual observation. Then, the synthesized silver nanoparticles were characterized using UV-Visible spectroscopy and scanning electron microscopy (SEM). The change of color from yellow to reddish brown color confirmed the formation of silver nanoparticles. The silver surface plasmon resonance (SPR) band obtained in the expected visible range of UV-Visible spectroscopy confirmed the synthesis of the nanoparticles. SEM images showed that silver nanoparticles are roughly spherical and of uniform particle size, and the average particle size is 100 nm. Further, the maximum absorbance of SPR band was considerably varied with different process parameters used in the present study. The UV-Visible spectra of 2.5 g/100 mL of crude neem leaf extract without any dilution showed maximum absorbance in the expected range with the mixing ratio of (Neem and AgNO3) 1:8. However, the maximum absorbance of modified neem leaf extracts (pH 10) resulted lower in value than the crude extracts in the 20 times diluted sample with the mixing ratio of 1:9. Moreover, modified extract with UV radiation exposure increased the absorbance in the expected visible range. It concludes that fine tuning of the bioprocess parameters would enhance nanoparticle synthesis.

A Comparative Study for Detection of Melamine in Solution by Interference Sensing Using Functionalized Silver Nanoparticles

2018 ◽  
Vol 24 (8) ◽  
pp. 5849-5854
Author(s):  
Shrey A Shah ◽  
Rahul Gundesha ◽  
Jayesh P Ruparelia
Keyword(s):  
Silver Nanoparticles ◽  
Comparative Study ◽  
Rapid Detection ◽  
Leaf Extract ◽  
Room Temperature ◽  
Calotropis Procera ◽  
Visible Spectroscopy ◽  
Leaf Extracts ◽  
Functionalized Nanoparticles ◽  
Uv Visible

In this research an attempt has been made for instantaneous sensing of melamine, a potential milk adulterant, at room temperature with the help of bio-functionalized silver nanoparticles. The bio-functionalized nanoparticles were made using leaf extracts of Parthenium hysterophorous and Calotropis procera. Also these methods were compared with the nanoparticles that were functionalized with sulfanillic acid. Colorimetric change was the basis of sensing the melamine using these bio-functionalized silver nanoparticles. Melamine upto a limit of 0.1 ppm was detected by the particles prepared using Parthenium hysterophorous leaf extract at room temperature. UV-visible spectroscopy (200–800 nm range) was used to detect the changes in the absorbance of silver nanoparticles with the addition of melamine in different concentrations. DLS studies were carried out to confirm the presence of nanoparticles and to study their surface morphology during sensing. Comparative study showed that Parthenium hysterophorous (noxious hysterophorous) leaf extract was far better and accurate in detecting melamine and was as accurate as the silver nanoparticles functionalized with sulfanillic acid. This can be attributed to the fact that Parthenium hysterophorous leaf extract contains caffeic acid which worked as a reducing agent and also as the bio functionalized chemical. Thus, this method can be further used as a rapid detection of melamine. In addition, this method can be converted into prototype for detection of melamine in industries.

scholarly journals Bio Synthesis and Characterization of Silver Nanoparticles Using Lagenaria siceraria Leaf Extract and their Antibacterial Activity

2014 ◽  
Vol 38 ◽  
pp. 35-45 ◽  
Author(s):  
B. Anandh ◽  
A. Muthuvel ◽  
M. Emayavaramban
Keyword(s):  
Silver Nanoparticles ◽  
Leaf Extract ◽  
Face Centered Cubic ◽  
Lagenaria Siceraria ◽  
Human Pathogens ◽  
X Ray Diffraction ◽  
Visible Spectroscopy ◽  
X Ray ◽  
Ft Ir ◽  
Uv Visible

The present investigation demonstrates the formation of silver nanoparticles by the reduction of the aqueous silver metal ions during exposure to the Lagenaria siceraria leaf extract. The synthesized AgNPs have characterized by UV-visible spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) techniques. AgNPs formation has screened by UV-visible spectroscopy through colour conversion due to surface plasma resonance band at 427 nm. X-ray diffraction (XRD) confirmed that the resulting AgNPs are highly crystalline and the structure is face centered cubic (fcc). FT-IR spectrum indicates the presence of different functional groups present in the biomolecules capping the nanoparticles. Further, inhibitory activity of AgNPs and leaf extract were tested against human pathogens like gram-pastive (Staphylococcus aureus, Bacillus subtilis), gram-negative (Escherichia coli and Pseudomonas aeruginosa). The results indicated that the AgNPs showed moderate inhibitory actions against human pathogens than Lagenaria siceraria leaf extract, demonstrating its antimicrobial value against pathogenic diseases

Biosynthesis of silver nanoparticles using lavender leaf and their applications for catalytic, sensing, and antioxidant activities

2016 ◽  
Vol 5 (6) ◽  
Author(s):  
Brajesh Kumar ◽  
Kumari Smita ◽  
Luis Cumbal
Keyword(s):  
Silver Nanoparticles ◽  
Leaf Extract ◽  
Antioxidant Activities ◽  
Present Report ◽  
X Ray Diffraction ◽  
Visible Spectroscopy ◽  
X Ray ◽  
Transmission Electron ◽  
Red Color ◽  
Uv Visible

AbstractThe present report summarizes an eco-friendly approach for the biosynthesis of silver nanoparticles (AgNPs) using the leaf extract of lavender. Initially, the synthesis of AgNPs was visually observed by the appearance of a wine red color. The optical property, morphology, and structure of as-synthesized AgNPs were characterized by UV-visible spectroscopy, dynamic light scattering, transmission electron microscopy, and X-ray diffraction analyses. All characterization data revealed the formation of crystalline and spherical AgNPs (Ag/Ag

scholarly journals Biosynthesis and Characterisation of Silver Nanoparticles using Leaf Extract of Achras sapota l. for its Antimicrobial Activity

2020 ◽  
pp. 246-256
Author(s):  
Maphibanri Maring ◽  
Akila Elias ◽  
V. B. Narayanaswamy
Keyword(s):  
Antimicrobial Activity ◽  
Silver Nanoparticles ◽  
Leaf Extract ◽  
Colour Change ◽  
Visible Spectroscopy ◽  
Sem And Tem ◽  
Achras Sapota ◽  
Uv Visible ◽  
Biosynthesized Agnps ◽  
Ethanolic Leaf Extract

<p>Nanotechnology is a field that is rapidly growing, making an impact in all spheres of human life. In the current study, silver nanoparticles were synthesized using the ethanolic leaf extract of <em>Achras sapota. </em>Characterization was carried out using UV-Visible spectroscopy, FTIR, XRD, SEM and TEM. The formation of AgNPs was confirmed through UV-Visible spectroscopy by the colour change. Based on the XRD pattern, the crystalline property of the AgNPs was established. The functional group present in the ethanolic leaf extract of <em>Achras sapota</em> is responsible for the reduction of the Ag<sup>+</sup> ion which was studied through FTIR. From the SEM and TEM analysis, it was found that the formed nanoparticles are spherical in shape and nano in size. The biosynthesized AgNPs was evaluated for its antimicrobial activity against gram positive bacteria (<em>S. aureus and L. bacillus</em>) and gram negative bacteria (<em>E. coli and P. aeruginosa</em>) using disc diffusion for preliminary screening of antimicrobial activity and dilution method for evaluation of antibacterial effectiveness and effect of silver nanoparticles on bacterial growth and it was found to exhibit potential antimicrobial activity. The biosynthesized AgNPs was found to be efficient in terms of reaction time as well as stability, eco-friendly and cost effective.</p>

scholarly journals SYNTHESIS OF SILVER NANOPARTICLES FROM THE MEDICINAL PLANT BAUHINIA ACUMINATA AND BIOPHYTUM SENSITIVUM–A COMPARATIVE STUDY OF ITS BIOLOGICAL ACTIVITIES WITH PLANT EXTRACT

2016 ◽  
Vol 9 (1) ◽  
pp. 22 ◽  
Author(s):  
Elizabath Antony ◽  
Mythili Sathiavelu ◽  
Sathiavelu Arunachalam
Keyword(s):  
Silver Nanoparticles ◽  
Plant Extract ◽  
Silver Nanoparticle ◽  
Plant Extracts ◽  
Biological Activities ◽  
Alpha Tocopherol ◽  
Visible Spectroscopy ◽  
Leaf Extracts ◽  
Uv Visible ◽  
Dpph Scavenging

Objective: The aim of current study was to synthesise silver nanoparticles from the leaf extracts (aqueous and methanol) of two medicinal plants Bauhinia acuminata and Biophytum sensitivum and to compare its biological activities with that of plant extract.Methods: Silver nanoparticles were synthesised, and it was characterised using UV-Visible spectroscopy and scanning electron microscope (SEM). Fourier transform infrared spectroscopy (FTIR) and GC-MS analysis were done for silver nanoparticle extract. The biological activities such as DPPH scavenging assay, haemolytic assay and antimicrobial assay were done for both nanoparticle and plant extract.Results: The UV-Visible spectroscopy showed the formation of nanoparticles in a size range of 400-460 nm. GC-MS analysis showed the presence of biologically active compounds like DL-alpha-tocopherol and Alpha-tocopherol-beta-D-mannose. FTIR analysis of silver nanoparticles and leaf extracts showed the formation of aldehydes, alkenes, amines, alcohols, etc., which confirmed the presence of the compounds present in plant extracts. SEM image showed the formation of nanoparticles of size 2 micrometre. Phytochemical analysis of plant extracts showed the presence of carbohydrates, phenols, flavonoids, saponins, tannins and terpenoids. The methanol extract of Bauhinia acuminata showed high DPPH scavenging activity of 90% compared to that of the silver nanoparticle. The percentage hemolysis of all extracts was found to be 6%-39%. The antimicrobial activity of leaf extracts showed excellent activity towards Bacillus cereus and Listeria monocytogens.Conclusion: The results of present study showed that the silver nanoparticle synthesised from the plant extract has many bioactive compounds and it was found to have significant biological activities but comparatively lesser than plant extract. It concludes the both plant and nanoparticle extract can be used as a potential resource for therapeutic purpose.

PENGARUH EKSTRAK DAUN MIMBA TERHADAP PERKEMBANGAN HAMA Callosobruchus chinensis L. (Coleoptera : Bruchidae)

AGRICA ◽  
2019 ◽  
Vol 1 (2) ◽  
pp. 32-37
Author(s):  
Yustina M.S.W Puu ◽  
Hildegardis Nalti Nansi
Keyword(s):  
Mung Bean ◽  
Leaf Extract ◽  
Callosobruchus Chinensis ◽  
Spawning Activity ◽  
Green Beans ◽  
Leaf Extracts ◽  
Randomized Design ◽  
Completely Randomized Design ◽  
Contact Poison ◽  
Neem Leaf Extract

Callosobruchus Chinensis is a pest that damages mung bean seeds in storage and causes damage to both the quality and quantity of seeds. This study aims to determine the effectiveness of neem leaf extracts in suppressing the development of the Callosobruchus Chinensis pest as one of the postharvest pests in the commodity green beans. This research conducted at the Laboratory of the Faculty of Agriculture, University of Flores, by using a Completely Randomized Design (CRD) with five treatments and three replications. The concentration of neem leaf extract treatment is 0 ml / l, 25 ml / l, 30 ml / l, 35 ml / l, and 40 ml / l. The results showed that the concentration of neem leaf extract 40 ml / l caused mortality of C. Chinensis imago as contact poison by 99% and nerve poison by 47%. While the effectiveness of the limb leaf extract on spawning activity was 86%.

scholarly journals Green synthesis of silk sericin-embedded silver nanoparticles and their antibacterial application against multidrug-resistant pathogens

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Md. Abdullah Al Masud ◽  
Hamid Shaikh ◽  
Md. Shamsul Alam ◽  
M. Minnatul Karim ◽  
M. Abdul Momin ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Green Synthesis ◽  
Bombyx Mori ◽  
Multidrug Resistant ◽  
Visible Spectroscopy ◽  
Silk Sericin ◽  
X Ray ◽  
Synthesis Strategy ◽  
Uv Visible ◽  
Multidrug Resistant Pathogens

Abstract Background The green synthesis strategy of metallic nanoparticles (NPs) has become popular due to being environmentally friendly. Stable silver nanoparticles (AgNPs) have been synthesized by natural products such as starch, soy protein, various extract of leaves, barks, and roots functioning both as reducing and stabilizing agents. Likewise, silk sericin (SS) is a globular protein discarded in the silk factory might be used for NP synthesis. In this research, we focus on the green synthesis and stabilization of AgNPs by SS as well as assessment of their antibacterial activities against some drug-resistant pathogen. Results SS was extracted from Bombyx mori silkworm cocoons in an aqueous medium. 17 w/w% of dry sericin powder with respect to the cocoon’s weight was obtained by freeze-drying. Furthermore, AgNPs conjugated to sericin, i.e., SS-capped silver nanoparticles (SS-AgNPs) were synthesized by easy, cost-effective, and environment-friendly methods. The synthesized SS-AgNPs were characterized by UV-visible spectroscopy, Fourier-transform infrared-attenuated total reflection (FTIR-ATR) spectroscopy, transmission electron microscopy (TEM), and X-ray diffraction measurement. It has been found from the absorbance of UV-visible spectroscopy that a higher percent of SS-AgNPs was obtained at a higher concentration of silver nitrate solution. FTIR-ATR spectra showed that the carboxylate groups obtained from silk sericin act as a reducing agent for the synthesis of silver nanoparticles, while NH2+ and COO− act as a stabilizer of AgNPs. The X-ray diffractogram of SS-AgNPs was quite different from AgNO3 and sericin due to a change in the crystal structure. The diameter of AgNPs was around 20–70 nm observed using TEM. The synthesized SS-AgNPs exhibited strong antibacterial activity against multidrug-resistant pathogens, Escherichia coli and Pseudomonas aeruginosa. Minimal inhibitory/bactericidal concentrations against E. coli and P. aeruginosa were 20μg/mL. Conclusions This study encourages the use of Bombyx mori for the ecofriendly synthesis of SS-AgNPs to control multidrug-resistant microorganisms.

scholarly journals Optical and Photoacoustic Properties of Laser-Ablated Silver Nanoparticles in a Carbon Dots Solution

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5798
Author(s):  
Amir Reza Sadrolhosseini ◽  
Ganesan Krishnan ◽  
Suhaidi Shafie ◽  
Suraya Abdul Rashid ◽  
Sulaiman Wadi Harun
Keyword(s):  
Silver Nanoparticles ◽  
Carbon Dots ◽  
Thermal Effusivity ◽  
Nonlinear Susceptibility ◽  
Time Range ◽  
Raman Signal ◽  
Optical Parameters ◽  
Visible Spectroscopy ◽  
Transmission Electron ◽  
Uv Visible

This study used the carbon dots solution for the laser ablation technique to fabricate silver nanoparticles. The ablation time range was from 5 min to 20 min. Analytical methods, including Fourier transform infrared spectroscopy (FTIR), UV-visible spectroscopy, transmission electron microscopy, and Raman spectroscopy were used to categorize the prepared samples. The UV-visible and z-scan techniques provided optical parameters such as linear and nonlinear refractive indices in the range of 1.56759 to 1.81288 and 7.3769 × 10−10 cm2 W−1 to 9.5269 × 10−10 cm2 W−1 and the nonlinear susceptibility was measured in the range of 5.46 × 10−8 to 6.97 × 10−8 esu. The thermal effusivity of prepared samples, which were measured using the photoacoustic technique, were in the range of 0.0941 W s1/2 cm−2 K−1 to 0.8491 W s1/2 cm−2 K−1. The interaction of the prepared sample with fluoride was investigated using a Raman spectrometer. Consequently, the intensity of the Raman signal decreased with the increasing concentration of fluoride, and the detection limit is about 0.1 ppm.

scholarly journals Optimization of Green Synthesis of Silver Nanoparticles from Leaf Extracts ofPimenta dioica(Allspice)

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Akshay Rajeev Geetha ◽  
Elizabeth George ◽  
Akshay Srinivasan ◽  
Jameel Shaik
Keyword(s):  
Silver Nanoparticles ◽  
Green Synthesis ◽  
Leaf Extract ◽  
Synthesis Method ◽  
Leaf Extracts ◽  
Synthesis Of Nanoparticles ◽  
Hot Air ◽  
Vis Spectroscopy ◽  
Pimenta Dioica ◽  
First Time

Production of silver nanoparticles from the leaf extracts ofPimenta dioicais reported for the first time in this paper. Three different sets of leaves were utilized for the synthesis of nanoparticles—fresh, hot-air oven dried, and sun-dried. These nanoparticles were characterized using UV-Vis spectroscopy and AFM. The results were diverse in that different sizes were seen for different leaf conditions. Nanoparticles synthesized using sun-dried leaves (produced using a particular ratio (1 : 0.5) of the leaf extract sample and silver nitrate (1 mM), resp.) possessed the smallest sizes. We believe that further optimization of the current green-synthesis method would help in the production of monodispersed silver nanoparticles having great potential in treating several diseases.

scholarly journals Epoxy/Silicone Blend Loaded with N-Doped CNT Composites: Study on the Optoelectronic Properties

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Younes Ziat ◽  
Hamza Belkhanchi ◽  
Maryama Hammi ◽  
Ousama Ifguis
Keyword(s):  
Thin Films ◽  
Urbach Energy ◽  
Optical Transition ◽  
Sol Gel ◽  
Visible Range ◽  
Visible Spectroscopy ◽  
Glass Substrates ◽  
Optical Gap ◽  
Ito Glass ◽  
Uv Visible

Thin films of epoxy/silicone loaded with N-CNT were prepared by a method of sol-gel and deposited on ITO glass substrates at room temperature. The properties of the loaded monolayer samples (0.00, 0.07, 0.1, and 0.2 wt% N-CNTs) were analyzed by UV-visible spectroscopy. The transmittance for the unloaded thin films is 88%, and an average transmittance for the loaded thin film is about 42 to 67% in the visible range. The optical properties were studied from UV-visible spectroscopy to examine the transmission spectrum, optical gap, Tauc verified optical gap, and Urbach energy, based on the envelope method proposed by Swanepoel (1983). The results indicate that the adjusted optical gap of the film has a direct optical transition with an optical gap of 3.61 eV for unloaded thin films and 3.55 to 3.19 eV for loaded thin films depending on the loading rate. The optical gap is appropriately adapted to the direct transition model proposed by Tauc et al. (1966); its value was 3.6 eV for unloaded thin films and from 3.38 to 3.1 eV for loaded thin films; then, we determined the Urbach energy which is inversely variable with the optical gap, where Urbach’s energy is 0.19 eV for the unloaded thin films and varies from 0.43 to 1.33 eV for the loaded thin films with increasing rate of N-CNTs. Finally, nanocomposite epoxy/silicone N-CNT films can be developed as electrically conductive materials with specific optical characteristics, giving the possibility to be used in electrooptical applications.

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