Browsing by Author "Chandar Shekar, B"

Now showing 1 - 3 of 3

NATURAL FUELS (HONEY AND COW URINE) ASSISTED COMBUSTION SYNTHESIS OF ZINC OXIDE NANOPARTICLES FOR ANTIMICROBIAL ACTIVITIES
(Elsevier, 2021-05-15) Ranjithkumar, B; Ramalingam, H B; Ranjith Kumar, E; Srinivas, Ch; Magesh, G; Sharmila Rahale, C; Nashwa M, El-Metwaly; Chandar Shekar, B
A novel green synthesis of the combustion pathway was adopted for the preparation of ZnO nanoparticles using Honey and Cow urine. The effects of honey and cow urine on crystalline size, structure, morphology, band gap and thermal properties of ZnO nanoparticles have been analyzed. The polycrystalline hexagonal wurtzite structure of ZnO nanoparticles is confirmed by XRD spectra. The mean crystalline sizes of the ZnO nanoparticles were 23 nm and 29 nm respectively, for the honey and cow urine phase. The external morphology and grain size of the products have been visualized via FE-SEM and TEM. The average sizes of the grains of the ZnO nanoparticles were perfectly associated with the crystalline size measured from the XRD. Spherical and hexagonal shaped nanostructures were reported using FE-SEM and TEM micrographs. The optical absorption spectra of ZnO nanoparticles have been analyzed using UV–Vis spectrometry. In the FT-IR spectra, around 400 cm−1 to 600 cm−1 range have been allotted to the Zn–O vibration. The thermal properties of ZnO nanoparticles have been analyzed using TGA. Changes in weight loss for different ZnO nanoparticles using honey and cow urine have been documented. Gram Positive (B.Subtilis) and Gram-Negative (E.Coli)Bacteria were tested using plate counting technique to study the antimicrobial activity of ZnO nanoparticles prepared by cow's urine and honey. Compared with cow urine-prepared ZnO nanoparticles, honey-assisted ZnO nanoparticles demonstrate strong antibacterial activity.
PSIDIUM GUAJAVA: A NOVEL PLANT IN THE SYNTHESIS OF SILVER NANOPARTICLES FOR BIOMEDICAL APPLICATIONS
(Innovare Academic Sciences, 2018) Sharmila, C; Ranjith Kumar, R; Chandar Shekar, B
Synthesis of silver nanoparticles (AgNPs) using a simple, cost-effective and environmentally friendly green route approach and to study the antibacterial activity of AgNPs against human pathogens.
SHAPE CONTROLLED SYNTHESIS OF DEXTRAN SULFATE STABALIZED SILVER NANOPARTICLES: BIOCOMPATIBILITY AND ANTICANCER ACTIVITY
(IOP Publishing Ltd, 2019-01) Sharmila, C; Prabhavathi, V; Dinesh, M; Ranjith Kumar, R; Chandar Shekar, B
Three Dimensional button, flower and sphere shaped microstructure of silver nanoparticles dispersed in dextran sulfate matrix were synthesized using silver nitrate, trisodium citrate and dextran sulfate. Three different amount of dextran sulfate (2 drops, 10 drops and 15 drops) were added to each 10 ml of silver nanoparticles to make three different solution mixtures, which was then subjected to different characterization techniques. The XRD study of flower shaped dextran sulfate stabilized silver nanoparticles showed a diffraction pattern corresponding to face centered cubic structure of Ag crystals. The FESEM image shows a well defined three dimensional button shaped microstructure for 2 drops of dextran sulfate, flower shaped microstructure for 10 drops of dextran sulfate and sphere shaped microstructure for 15 drops of dextran sulfate. Based on the morphological structure of the synthesized nanoparticle the absorption property was discussed, the absorption band varied from 429 nm to 434 nm. The nanoparticles prepared using dextran sulfate of high concentration (15 drops) shows a blue shift in absorbance spectra, indicating smaller size of AgNPs with high absorbance property. The results reveal that the surface morphology affects the absorption behavior of the nanoparticles. The results of cytotoxicity assay against human vero cell lines revealed that flower shaped dextran stabilized AgNPs shows ≥ 90% cell viability indicating the biocompatibility of the nanoparticles. The In-vitro anticancer activity of the synthesized Ag-DS nanoparticles against human breast cancer cell line MCF-7, was studied. The results of the present study indicated that the Ag-DS nanoparticles can be a potent anticancer agent.