Efforts have been made to prepare nanocomposites of a-Fe2O3-ZnO by wet chemical route with varying concentrations of the precursors.The microstructural properties of the samples are investigated by powder X-ray diffra...Efforts have been made to prepare nanocomposites of a-Fe2O3-ZnO by wet chemical route with varying concentrations of the precursors.The microstructural properties of the samples are investigated by powder X-ray diffractometry（PXRD） and Transmission electron microscopy.Initial concentration of Zn ions（up to 20 at%） leads to the formation of nanocomposites of a-Fe2O3 and ZnO.Evolution of ZnFe2O4 phase is detected by the substitution of higher concentration of Zn2？（30 at%） in the sample.The average size of the nanoparticles remains in the range of 22–27 nm as obtained from XRD data.The results obtained from electron microscopic studies are also close to these values.Photoluminescence measurement shows the excitonic peak of ZnO around 390 nm which gets strengthened with Zn addition.FTIR spectra show the metal–oxygen band below 700 cm-1.Room temperature Mssbauer studies of the samples show the transition of iron oxide form antiferromagnetic state to paramagnetic state with increasing concentration of Zn2？.Sharp quenching of hyperfine field with Zn concentration is observed as the Hintvalue reduced to zero from 51 T.展开更多
To evaluate the bactericidal,and cytotoxicity properties of silver nanoparticles synthesized from root extract of Asparagus racemosus.The physical properties of these nanoparticles were characterized by Transmission E...To evaluate the bactericidal,and cytotoxicity properties of silver nanoparticles synthesized from root extract of Asparagus racemosus.The physical properties of these nanoparticles were characterized by Transmission Electron Microscopy(TEM),Scanning Electron Microscopy(SEM),XRD and UV-Vis spectrophotometric analysis.The biochemical properties were assayed by antibacterial study,cytotoxicity assay using cancer cell line.The formation of silver nanoparticles was confirmed by UV-VIS spectroscopic analysis which showed absorbance peak at 420 nm.X-ray diffraction photograph indicated the face centered cubic structure of the synthesized AgNPs.TEM has displayed the different dimensional images of biogenic silver nanoparticles with particle size distribution ranging from 30-50 nm.Silver particles are spherical in shape.The EDX analysis was used to identify the elemental composition of synthesized AgNPs.Antibacterial activity of the synthesized AgNPs against three Gram positive and Gram negative bacteria strains like Staphylococcus aureus,Escherichia coli and Pseudomonas aeruginosa carried out showed significant zones of inhibition.The cytotoxicity study by AgNPs also showed cytotoxicity on ovarian cancer cell line PA-1.The present study confirms that the AgNPs have great promise as antibacterial,and anticancer agent.展开更多
Green synthesis of silver nanoparticles(AgNPs)is gaining momentum in the field of nano-research.Scoparia dulcis leaves were used as a reducing agent for the synthesis of silver nanoparticles from an aqueous solution o...Green synthesis of silver nanoparticles(AgNPs)is gaining momentum in the field of nano-research.Scoparia dulcis leaves were used as a reducing agent for the synthesis of silver nanoparticles from an aqueous solution of silver nitrate(AgNO_(3)).Synthesized AgNPs were characterized by UV-Vis spectroscopy,XRD,SEM with EDAX and TEM.UV-VIS surface plasmon resonance spectroscopy was observed at 430 nm.XRD data depicts that the NPs are crystalline in nature.The EDAX data indicate that 63.76%presence of Ag metal.The TEM&SEM results indicate that size of the AgNPs ranges from 15-25 nm.The results also support that spherical shape of the nanoparticles.In addition,the NPs are in polydispersed condition.The antimicrobial activities indicate significant inhibition of the growth of three pathogenic bacteria such as Pseudomonas ariginosa,Bacillua subtillis and Staphylococcus aureous.Cytotoxicity of this nanoparticle showed that this Ag-NP also has more cytotoxic effect on a lung cancer cell line,A549 cells compared to ovarian cancer cell line,PA1 indicating a possible therapeutic use of this AgNP.展开更多
文摘Efforts have been made to prepare nanocomposites of a-Fe2O3-ZnO by wet chemical route with varying concentrations of the precursors.The microstructural properties of the samples are investigated by powder X-ray diffractometry（PXRD） and Transmission electron microscopy.Initial concentration of Zn ions（up to 20 at%） leads to the formation of nanocomposites of a-Fe2O3 and ZnO.Evolution of ZnFe2O4 phase is detected by the substitution of higher concentration of Zn2？（30 at%） in the sample.The average size of the nanoparticles remains in the range of 22–27 nm as obtained from XRD data.The results obtained from electron microscopic studies are also close to these values.Photoluminescence measurement shows the excitonic peak of ZnO around 390 nm which gets strengthened with Zn addition.FTIR spectra show the metal–oxygen band below 700 cm-1.Room temperature Mssbauer studies of the samples show the transition of iron oxide form antiferromagnetic state to paramagnetic state with increasing concentration of Zn2？.Sharp quenching of hyperfine field with Zn concentration is observed as the Hintvalue reduced to zero from 51 T.
文摘To evaluate the bactericidal,and cytotoxicity properties of silver nanoparticles synthesized from root extract of Asparagus racemosus.The physical properties of these nanoparticles were characterized by Transmission Electron Microscopy(TEM),Scanning Electron Microscopy(SEM),XRD and UV-Vis spectrophotometric analysis.The biochemical properties were assayed by antibacterial study,cytotoxicity assay using cancer cell line.The formation of silver nanoparticles was confirmed by UV-VIS spectroscopic analysis which showed absorbance peak at 420 nm.X-ray diffraction photograph indicated the face centered cubic structure of the synthesized AgNPs.TEM has displayed the different dimensional images of biogenic silver nanoparticles with particle size distribution ranging from 30-50 nm.Silver particles are spherical in shape.The EDX analysis was used to identify the elemental composition of synthesized AgNPs.Antibacterial activity of the synthesized AgNPs against three Gram positive and Gram negative bacteria strains like Staphylococcus aureus,Escherichia coli and Pseudomonas aeruginosa carried out showed significant zones of inhibition.The cytotoxicity study by AgNPs also showed cytotoxicity on ovarian cancer cell line PA-1.The present study confirms that the AgNPs have great promise as antibacterial,and anticancer agent.
文摘Green synthesis of silver nanoparticles(AgNPs)is gaining momentum in the field of nano-research.Scoparia dulcis leaves were used as a reducing agent for the synthesis of silver nanoparticles from an aqueous solution of silver nitrate(AgNO_(3)).Synthesized AgNPs were characterized by UV-Vis spectroscopy,XRD,SEM with EDAX and TEM.UV-VIS surface plasmon resonance spectroscopy was observed at 430 nm.XRD data depicts that the NPs are crystalline in nature.The EDAX data indicate that 63.76%presence of Ag metal.The TEM&SEM results indicate that size of the AgNPs ranges from 15-25 nm.The results also support that spherical shape of the nanoparticles.In addition,the NPs are in polydispersed condition.The antimicrobial activities indicate significant inhibition of the growth of three pathogenic bacteria such as Pseudomonas ariginosa,Bacillua subtillis and Staphylococcus aureous.Cytotoxicity of this nanoparticle showed that this Ag-NP also has more cytotoxic effect on a lung cancer cell line,A549 cells compared to ovarian cancer cell line,PA1 indicating a possible therapeutic use of this AgNP.
