Formulation of Clitoria ternatea Leaves-mediated Silver Nanoparticles to Control Aedes aegypti Larvae

2021 ◽  
Vol 53 (03) ◽  
pp. 190-200
Author(s):  
Sarita Kumar ◽  

Introduction: Global rise in the Aedes-borne diseases and harmful effects of synthetic insecticides has diverted research to explore secondary metabolites in plants as mosquito control agent in the form of nanoparticles. Current study investigated Clitoria ternatea-mediated nanoparticles against Aedes aegypti. Methods: The aqueous and hexane leaf extracts of C. ternatea were assayed against Ae. aegypti early fourth instars. The extract-mediated silver nanocomposites (AgNCs) were synthesized after optimizing the volume and concentration of silver nitrate solution. The synthesis was tracked by the colour change of reaction mixture from pale yellow to dark brown followed by monitoring with UV-Visible spectroscopy and Dynamic Light Scattering. Results: The biosynthesis of 3 mM, 4 mM and 5 mM AgNCs was traced at 438, 401 and 407 nm, respectively. The average particle size distribution ranged from 34.62 to 60.64 nm and polydispersity index was 0.6-0.7. The 24 h larval exposure with aqueous and hexane leaf extracts demonstrated respective LC50 values of 53.057 and 42.179 mg/L, which decreased significantly on larvicidal assay with NCs. The 5mM AgNCs showed the maximum efficiency with LC50 of 10.317 mg/L after 24 h. Scanning and transmission electron microscopy images demonstrated a spherical, poly-dispersed structure with diameter in the 1-27 nm range. The assays against non-targets; Moina and Cyclops ascertained the eco-safety of NCs. Conclusion: The study demonstrated the C. ternatea leaf extract as possible effective mosquito nano-larvicide, alternate to traditional insecticides. Field studies, which could not be held due to the current pandemic, would further ascertain the possible use of these NCs against Aedes larvae.

Author(s):  
Liem Le ◽  
The Nguyen ◽  
Dieu Nguyen

In this work, silver nanoparticles (AgNPs) were synthesized rapidly and eco-friendlily using the extract of Mulberry leaves and aqueous solution of silver nitrate without any toxic chemical [1,2]. The Mulberry leaves extract acts as both reducing agent and stabilizing agent. The UV-Vis spectrum shows peak at 430 nm. The TEM image of synthesized AgNPs sample shows spherical shaped particles whose size range from 15 to 20 nm. TEM image of nano silver solution sample synthesized by microwave assisted method shows nearly spherical particles with an average particle size of 10 nm. The absorption UV-vis spectrum of silver nanoparticles synthesized by microwave assisted method (AgNPsmw) shows a sharp absorption band around 415 nm. After two month storage of AgNPsmw, the absorption spectrum of AgNPsmw was taken again. The UV-Vis spectrum shows negligible peak changes of silver nanoparticles have occurred after two months of storage. The synthesized AgNPs material could be used as an antimicrobial, used in the field of textile and in wastewater treatment.


2018 ◽  
Vol 55 (1A) ◽  
pp. 45
Author(s):  
Le Thi An Nhien

In this study, silver nanoparticles (AgNPs) were prepared by gamma rays irradiation of 1.0, 2.5, 5.0 and 10 mM silver nitrate solution using chitosan as a stabilizer. UV spectra, morphology and size of AgNPs irradiated at different doses were characterized by using UV-vis spectrophotometer and TEM images. The obtained results indicated that the average size of AgNPs increased by the increase of silver concentration in irradiated solution or the degree of acetylation of chitosan, while the increase of chitosan concentration was found to be a functional key for reducing the average size of particles in AgNPs product. In vitro test, AgNPs inhibited the growth of Corynespora cassiicola. In particularly, the inhibitory efficiency of AgNPs on the growth of C. cassiicola on rubber leaf extract media increased from 52.1 to 100 % when the average particle size of particles in AgNPs product decreased from 15 to 5 nm at the concentration of 50 ppm. In addition, the increase of AgNPs concentration from 10 to 90 ppm also enhanced the antifungal activity to be from 6.3 to 100 %, respectively. It suggests that the silver nanoparticles/chitosan (AgNPs/chitosan) synthesized by γ-rays irradiation method is a very promising fungicidal product applying for treating C. cassiicola, a serious pathogen fungus on rubber trees.


2019 ◽  
Vol 4 (2) ◽  
pp. 86
Author(s):  
Astuti Amin ◽  
Nur Khairi ◽  
Eko Allo

The research of manufacturing chitosan from shrimp shell waste , and their use as a stabilizer in the manufacture of silver nanoparticles has been done. The aim of the research was to synthesize silver nanoparticles using chitosan as a stabilizer by chemical reduction method and determine the effect of chitosan concentration on the stability of Ag nanoparticles. In this study, the raw material used is shrimp shell powder and then processed in several stages, eliminating proteins, demineralization, and deacetylation. Chitosan obtained is 16.4 % of shrimp shell powder, with a degree of deacetylation of 85 %. Chitosan is used to synthesize silver nanoparticles as a reducing agent of silver ions in silver nitrate solution and is expected to be stabilizer. Sample containing 45 mg of chitosan and 1000 ppm AgNO3 has 421,60 nm of maximum wavelength, and the average particle size is 154.07 nm.


2013 ◽  
Vol 1 (04) ◽  
pp. 16-24 ◽  
Author(s):  
Anu Kumar ◽  
Kuldeep Kaur ◽  
Sarika Sharma

The present study reports the synthesis of silver nanoparticle using Morus nigra leaf extract were used as reducing agent for reduction of silver nitrate solution. The synthesis of silver nanoparticles was analyzed by UV-Visible spectroscopy, Scanning Electron Microscopy. The SEM analysis has shown that size of silver nanoparticles synthesized from leaves extract of M.nigra was 200 nm and seems to be spherical in morphology. Morphology of chemically synthesized silver nanoparticles is nearly spherical and of size ranges from 300-500 nm. The average particle size analyzed from SEM analysis was observed to be 350 nm. This article has discussed the synthesis of silver nanoparticles generated from plant extract, characterization and antibacterial analysis. In this study the antibacterial activity was examined against six MTCC cultures collected from IMTECH Chandigarh, Including both gram positive and gram negative bacteria such as P.aeruginosa, S.aureus, B.subtilis, E.coli, P.flourescens and Streptococus mutans. Out of these strains the antimicrobial activity of the silver nanoparticles showed maximum zone of inbhition against P.flourescens (22 mm), P.aeruginosa (19 mm), S.aureus (18 mm) and least effective against E.coli (15mm). In contrast chemically synthesized silver nanoparticles were found most effective against S.aureus (13 mm) and B.subtilis (12mm) and almost ineffective against Streptococcus mutans (6 mm) and P.flourescens (4 mm). In the concluding remarks, the silver nanoparticles synthesized using M.nigra leaves extract would be a better antimicrobial effective against various bacterial species.


Author(s):  
Anjali A. Athawale ◽  
Prachi P. Katre

Silver nanoparticles were synthesized by irradiating silver nitrate solution (10-4 M) (methanol:water as a solvent) with different concentrations of aniline as a stabilizer in a 60Co g-ray source at a dose rate of 1.1 kGy. The particles exhibiting maximum stability up to a period of 7 days were obtained at the concentration of 0.1M aniline. The average particle size of the nanoparticles as estimated from XRD and TEM was found to be ~23 nm. Silver-Polyaniline (Ag-Pani) nanocomposite was prepared by oxidative polymerization of aniline. The applicability of synthesized nanocomposite as a sensor was tested by exposing the same to different chemical vapors viz. alcohols, amines, ammonia, chloroform etc. The results revealed its selectivity towards ammonia vapors and a long term stability of response is observed up to a period of two months. The above results are well supported by FT-IR spectroscopy.


1996 ◽  
Vol 11 (5) ◽  
pp. 1199-1209 ◽  
Author(s):  
J. M. McHale ◽  
P. C. McIntyre ◽  
K. E. Sickafus ◽  
N. V. Coppa

An aqueous, all nitrate, solution-based preparation of BaTiO3 is reported here. Rapid freezing of a barium and titanyl nitrate solution, followed by low temperature sublimitation of the solvent, yielded a freeze-dried nitrate precursor which was thermally processed to produce BaTiO3. XRD revealed that 10 min at temperatures ≧600 °C resulted in the formation of phase pure nanocrystalline BaTiO3. TEM revealed that the material was uniform and nanocrystalline (10–15 nm). The high surface to volume ratio inherent in these small particles stabilized the cubic phase of BaTiO3 at room temperature. It was also found that the average particle size of the BaTiO3 produced was highly dependent upon calcination temperature and only slightly dependent upon annealing time. This result suggests a means of selection of particle size of the product through judicious choice of calcination temperature. The experimental details of the freeze-dried precursor preparation, thermal processing of the precursor, product formation, and product morphology are discussed.


Author(s):  
SNEHA THAKUR ◽  
KRISHNA MOHAN G

Objective: The main objective of the research work is to evaluate the antityrosinase potential of onion DNA silver nanoparticles (AgNPs). Methods: The onions were procured from the local market and DNA was extracted from onions using detergent and methylated spirit. The isolated DNA was selected for synthesis of AgNPs which acts as capping and reducing agent. About 10 ml of the DNA extract was added to 90 ml of 0.1 N silver nitrate solution. After 24 h incubation, the solution turned dark brown, which indicates the formation of AgNPs. The synthesized DNA AgNPs were characterized by ultraviolet-visible, Fourier transform infrared (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and dynamic light scattering (DLS) studies. Results: The results revealed that the particles were uniform in shape with face-centered cubic structure. The particles are 153±20.4 nm in size and were no signs of agglomeration measured by DLS studies. The FTIR spectroscopy revealed B form of DNA along with strong N-H stretching, C=N stretching, and also asymmetric vibrations of phosphate groups characteristic for DNA molecule. The XRD studies revealed the face-centered cubic structure. SEM studies revealed the spherical structure with average particle size of 150±0.1 nm for single DNA nanoparticles. The onion DNA AgNPs were further investigated for its antityrosinase activity against the standard kojic acid and were to have anticancer potential nearer to the standard. Conclusion: From the results, it is evident that the synthesized onion DNA AgNPs have antityrosinase potential and can be further investigated for in vivo anticancer potential in future.


2015 ◽  
Vol 832 ◽  
pp. 132-138
Author(s):  
E. Thanikaivelan ◽  
R. Jothilakshmi ◽  
P. Murugakoothan

The copper nanoparticles were synthesized by green technology using leaf extracts of Ocimum sanctum. The synthesized copper nanoparticles were confirmed by the change of colour after the addition of leaf extract into the copper sulfate solution. The synthesized copper was characterized by X-ray Diffraction (XRD), transmission electron microscopy (TEM) and UV-vis absorption spectroscopy. The copper nanoparticles are crystallized with FCC structure. The synthesized copper nanoparticles exhibit spherical morphology with average particle size of 20 nm. The copper nanoparticle exhibits absorption broad band between 550 nm – 575 nm. The optical trapping effect of Gaussian beam acting on a copper nanoparticle in Rayleigh regime was studied. The optical scattering and optical gradient forces were calculated for 20 nm copper particle.


2020 ◽  
Vol 9 (1) ◽  
pp. 87-96 ◽  
Author(s):  
Samaira Yasmin ◽  
Shazia Nouren ◽  
Haq Nawaz Bhatti ◽  
Dure Najaf Iqbal ◽  
Shan Iftikhar ◽  
...  

AbstractCurrently, the green route for synthesis of silver nanoparticles (Ag NPs) using plants leaf extract is an emerging research area in nanotechnology. The present study was explored for synthesis, characterization and catalytic application of Ag NPs using Diospyros lotus fresh leaf extracts. Factors affecting the synthesis were optimized and optimum conditions were pH of 8.6, silver nitrate (AgNO3) concentration of 1.5 mM and 10 mL leaf extract. Formation of Ag NPs was observed by change in color of reaction mixture from pale yellow to reddish brown. The synthesized Ag NPs were characterized using UV-Vis spectrophotometer, EDX, XRD and SEM analyses. UV-Vis spectrophotometer showed maximum absorbance peak in the range of 407 nm at different time intervals indicating formation of Ag NPs. SEM and XRD analysis confirmed face centered cubic structure and crystalline nature of biologically synthesized Ag NPs with average particle size of 27 nm. The purity of synthesized Ag NPs was revealed by EDX. Finally, photo catalytic activity (PCA) of Ag NPs was studied and 72.91% decolorization of industrial waste water was obtained at 54 h. Some important parameters like pH, turbidity, conductance; TSS, TDS, sulphide, sulphates, etc. were also monitored before and after treatment with Ag NPs.


2014 ◽  
Vol 809-810 ◽  
pp. 26-30
Author(s):  
Rong Liang Zhang ◽  
Shu Zhen Tang

PbS nanocrystals was synthesized by a heterogeneous reaction of hydrogen sulfide gas and lead nitrate solution containing EDTA in ethanol. The influenceof initial molar concentration ratio of EDTA/Pb (NO3)2 (CEDTA/CPb (NO3)2), volume ratio of ethanol/water (Vethanol/VH2O), pH value and flux of H2S on the particle size of PbS were investigated. The structure, morphology, particle size, and particle size distribution ranges of PbS were characterized by XRD, FE-SEM, and laser particle size analyzer, respectively. Increasing CEDTA/CPb (NO3)2, Vethanol/VH2O, and pH value, as well as decreasing the flux of H2S decrease the particle size of PbS. PbS nanocrystals have an average particle size of 69 nm, a narrow size distribution, and a quasi-spherical shape when CEDTA/CPb (NO3)2 is 1, Vethanol/VH2O is 1, pH is 3.5, and the flux of H2S is 20 ml/min.


Sign in / Sign up

Export Citation Format

Share Document