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Virudhunagar, India

Subbaraj P.,Devanga Arts College Autonomous | Ramu A.,Madurai Kamaraj University | Raman N.,Vhnsn College Autonomous
Journal of Saudi Chemical Society | Year: 2015

A new bidentate NO type Schiff base ligand (HL), derived from 2-hydroxy-4-methoxyphenyl)phenylmethanone with aniline and its metal(II) [M = Mn, Co, Ni, Cu and Zn] complexes has been synthesized. The synthesized ligand and the metal(II) complexes were structurally characterized by analytical, spectral (FT-IR, UV-vis., 1H NMR, FAB-Mass, TGA/DTA and EPR) as well as molar conductance and magnetic studies. All the complexes are non-electrolytes having 1:2 stoichiometry. They adopt tetrahedral and octahedral geometry. Thermal behavior of metal(II) complexes (1a-1c) shows loss of coordinated water molecules in the first step followed by the decomposition of ligand moieties in a respective manner and leads to form an air stable metal oxide as the final residue. Micro crystalline nature and the presence of coordinated water molecules have been confirmed by powder XRD, SEM and thermal analyses. The ligand and its complexes have efficient bio-efficacy, DNA binding and cleavage ability. © 2014 King Saud University. Source

Selvarani M.,Vhnsn College Autonomous | Prema P.,Vhnsn College Autonomous
Asian Journal of Pharmaceutical and Clinical Research | Year: 2013

Objective: Growing resistance of microorganisms to potent antibiotics has renewed a great interest towards investigating bactericidal properties of nanoparticles and their nanocomposites as an alternative. Therefore, the present study has been carried out to investigate and compare the antibacterial properties of copper (Cu) and zerovalent iron (Fe°) nanoparticles. Methods: Nanoparticles were synthesized by reducing aqueous solution of respective salt solution with sodium borohydride (NaBH4). The synthesized particles were further characterized by X-Ray Diffractogram (XRD), and Scanning Electron Microscopy (SEM) techniques to analyze size and morphology respectively. Antibacterial efficacy of metal nanoparticles was evaluated by agar well diffusion method. Results: Average size of the particles was found to be 17.25 nm (Cu) and 44.87 nm (Fe°). Energy-dispersive spectrum (EDS) of the nanoparticles dispersion confirmed the presence of elemental metals. The mechanism of microorganism inactivation is considered as species-dependent. Pseudomonas aeruginosa exhibited highest antibacterial sensitivity (26.00 ± 0.41 mm) to copper nanoparticles whereas Bacillus cereus offered maximum zone of inhibition (23.33 ± 0.89 mm) to Fe° nanoparticles. Conclusion: Results from this study signify that the Cu and Fe° nanoparticles potentiate the antibacterial action of both gram positive and gram negative bacteria. Source

Prema P.,Vhnsn College Autonomous | Iniya P.A.,Vhnsn College Autonomous | Immanuel G.,Manonmaniam Sundaranar University
RSC Advances | Year: 2016

Herein, the microbial mediated synthesis of gold nanoparticles (GNPs) was achieved via an easy biological protocol using Klebsiella pneumoniae (MTCC-4030). Gold ions in the reaction mixture were exposed to K. pneumoniae for the formation of colloidal GNPs. The characterization study indicated that the UV-vis spectral analysis of the GNPs showed a peak at 550 nm. XRD spectroscopy of the GNPs confirmed their crystalline nature. Scanning electron images of the GNPs showed that they were spherical in shape and were well dispersed. Atomic force microscopy revealed that the size range of the GNPs was between 10 and 15 nm. The FTIR study revealed the possible involvement of reductive groups on the surface of the nanoparticles. The antibacterial activity of the GNPs showed the highest inhibitory zone (25.60 mm) against Escherichia coli as an indicator strain. The synergistic effect of the GNPs obtained the highest fold increase (4.06) and activity index (3.210) against E. coli, followed by 2.610 activity index against Staphylococcus aureus using amoxycillin and streptomycin as standard antibiotics, respectively. © The Royal Society of Chemistry 2016. Source

Jothi S.,Vhnsn College Autonomous | Prithivikumaran N.,Vhnsn College Autonomous | Jeyakumaran N.,Vhnsn College Autonomous
International Journal of ChemTech Research | Year: 2014

Zirconium Oxide (ZrO2) is an interesting material in optical filters, gas sensors and protective coatings owing to their outstanding optical, chemical, thermal and mechanical properties. Zirconium Oxide thin films were deposited on glass substrates by sol gel dip coating method, using alcoholic solutions. The dipping solution was prepared from Zirconium OxychlorideOctahydrate and Isopropanol with Acetyl acetone. In order to find the influence of the number of layers on the properties of ZrO2 thin films, samples with different number of layers were prepared by repeating the dipping and drying processes. After coating, the sol gel derived films were heated at 500°C, to complete the dehydration of the ZrO2 precursors. Various characterization techniques were used to evaluate the crystalline structure and grain size (XRD), the morphology (SEM), surface bonding properties (FTIR) and luminescence properties (PL) of ZrO2 films. XRD data exhibited that at 500°C temperature nanosized ZrO2 films with tetragonal and monoclinic phases have been formed. FTIR spectra revealed the formation of Zr-O bond. Photoluminescence studies displayed a strong emission peak at 426 nm and relatively weak emission peak at 488 nm. Source

Jothi S.,Vhnsn College Autonomous | Prithivikumaran N.,Vhnsn College Autonomous | Jeyakumaran N.,Vhnsn College Autonomous
International Journal of ChemTech Research | Year: 2014

Zirconium Oxide (ZrO2) thin films were prepared on glass substrates by sol-gel dip coating method using Zirconium Oxychloride Octahydrate, Isopropanol and Acetyl acetone as precursor, solvent and stabilizer respectively. In the present work, the optical properties of the Zirconia thin films have been studied. Samples with different number of layers were prepared by repeating the dipping and drying processes. Then, the sol gel derived films were annealed at 500°C. The crystalline structure of the ZrO2 film was determined using X-ray diffraction. The films found to show tetragonal phases at the annealing temperature of 500°C. The UV-Visible transmission and reflectance spectra were used to observe the optical properties of the thin films. The average refractive index of the thin films was found to be 1.9, calculated using reflectance and transmission spectra. The measured band gap values of the ZrO2 thin films were nearly 4.8 eV. SEM analysis showed that the films have cracked plane morphology, as a result of their contraction during heat treatment. © 2014, Sphinx Knowledge House. All rights reserved. Source

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