Hyderabad, India
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Leela D.S.,Osmania University | Ushaiah B.,Osmania University | Anupama G.,Rbvrr Womens College | Sunitha M.,Government Polytechnic for Women | Kumari C.G.,Osmania University
Journal of Fluorescence | Year: 2015

The mixed ligand complexes MLA of Cu(II) and Co(II) with Schiff base derived from 4-amino antipyrine and 5-NO2 salicylaldehyde (2,3 -dimethyl-1-phenyl-4-(2-hydroxy-5-nitro benzylideneamino)-pyrazol-5-one) as ONO donor (L) and A∈=∈2,2 bipyridine (bpy),1,10 phenonthroline (1,10 phen) as N, N donor ligands have been prepared, owing to their biological and other applications. The structural features have arrived from their elemental analyses, magnetic susceptibility, molar conductance, Mass, IR, UV-VIS, powdered XRD and ESR spectral studies, that established MLA type of composition for the metal complexes. The electronic absorption spectral data of the complexes suggest an octahedral geometry around the central metal ion. The interaction of the complexes with Calf Thymus (CT) DNA has been studied using absorption spectra, viscosity measurements and fluorescence spectra. The binding constants (Kb) of the complexes were determined as 2.1∈×∈106 M-1 for complex 1, 2.5x106M-1 for complex 2, 1.16∈×∈106 M-1 for complex 3,1.25x106M-1 for complex 4, DNA cleavage experiments performed on pBR-322 plasmids using metal complexes in the presence of H2O2 showed that all the complexes afford a pronounced DNA cleavage. Molecular modelling studies were also performed to confirm the geometries of the complexes. The ligand and their metal complexes were screened for their antimicrobial activity against bacteria. The results showed that the metal complexes are biologically active. © 2014 Springer Science+Business Media New York.


Anupama B.,Rbvrr Womens College | Sunita M.,Government Polytechnic for Women | Shiva Leela D.,Osmania University | Ushaiah B.,Osmania University | Gyana Kumari C.,Osmania University
Journal of Fluorescence | Year: 2014

A series of transition metal complexes of Co(II), Ni(II), Zn(II), Fe(III) and VO(IV) have been synthesized involving the Schiff base, 2,3-dimethyl-1- phenyl-4-(2-hydroxy-3-methoxy benzylideneamino)-pyrazol-5-one(L), obtained by condensation of 4-aminoantipyrine with 3-methoxy salicylaldehyde. Structural features were obtained from their FT-IR, UV-vis, NMR, ESI Mass, elemental analysis, magnetic moments, molar conductivity and thermal analysis studies. The Schiff base acts as a monovalent bidentate ligand, coordinating through the azomethine nitrogen and phenolic oxygen atom. Based on elemental and spectral studies six coordinated geometry is assigned to Co(II), Ni(II), Fe(III) and VO(IV) complexes and four coordinated geometry is assigned to Zn(II) complex. The interaction of metal complexes with Calf thymus DNA were carried out by UV-VIS titrations, fluorescence spectroscopy and viscosity measurements. The binding constants (Kb) of the complexes were determined as 5 × 105 M-1 for Co(II) complex, 1.33 × 104 M-1 for Ni(II) complex, 3.33 × 105 M-1 for Zn(II) complex, 1.25 × 105 M-1 for Fe(III) complex and 8 × 105 M-1 for VO(IV) complex. Quenching studies of the complexes indicate that these complexes strongly bind to DNA. Viscosity measurements indicate the binding mode of complexes with CT DNA by intercalation through groove. The ligand and it's metal complexes were screened for their antimicrobial activity against bacteria. The results showed the metal complexes to be biologically active, while the ligand to be inactive. © 2014 Springer Science+Business Media New York.


Jyothi V.J.,RBVRR Womens College | Reddy M.S.,RBVRR Womens College | Anjaneyulu C.,RBVRR Womens College
Research Journal of Pharmaceutical, Biological and Chemical Sciences | Year: 2016

Anodization of Zr-Nb in 0.1M L-Ascorbic acid has been carried out. Kinetics of anodic oxidation of Zr-Nb has been studied at a constant current density of 8mA.cm-2 and at room temperature. The plots of formation voltage vs. time, reciprocal capacitance vs. time and reciprocal capacitance vs. formation voltage were drawn. From these plots, formation rate, current efficiency and differential field were calculated. The Addition of Solvent (Ethylene glycol) showed better kinetic results. For 20%, 40%, 60% and 80% aquo-glycolic media, the dielectric constant values are low leading to the marked improvement in the kinetics. The surface morphology of the anodic films was also studied by Scanning Electron Micrographs (SEM).


Reddy M.S.,RBVRR Womens College | Jyothi V.J.,RBVRR Womens College
Research Journal of Pharmaceutical, Biological and Chemical Sciences | Year: 2016

Kinetics of oxidation of cyclo pentanone, cyclo hexanone, cyclo heptanone and cyclo octanone by Chloramine-T (CAT) in the acid medium using aqueous acetic acid as solvent has been taken up in order to find out the nature of the reactive species and mechanism of the reaction. Under conditions [cyclic ketones] ≫ [CAT], the rate of oxidation exhibited pseudo first order dependence in [CAT] as seen from linearity of plot of log a/a-x vs time. The rate increases with increase in substrate. The order in [Sub] was found to be one from plot of log K1 vs log [cyclic ketone], [H+] was found to be fractional one. Solvent and salt effects were not considerable. The effect of toluene sulphonamide was negligible. No polymerisation was observed with added acrylamide. Suitable mechanism has been suggested and rate law consistent with experimental findings has been derived.


Jeevana Jyothi V.,Rbvrr Womens College | Anjaneyulu C.H.,Osmania University
Research Journal of Pharmaceutical, Biological and Chemical Sciences | Year: 2014

Anodization of Niobium in 0.1M L-Ascorbic acid has been carried out. Kinetics of anodic oxidation of Niobium has been studied at a constant current density of 8 mA.cm-2 and at room temperature. The plots of formation voltage vs. time, and reciprocal capacitance vs. time were drawn. From these plots, formation rate, current efficiency and differential field were calculated. The Addition of Solvent (Ethylene glycol at various concentrations) to the aqueous solution of L-ascorbic acid showed improvement in the kinetic results. The surface morphology of the anodic films was also studied by Scanning Electron Micrographs (SEM). Kinetics was studied at different temperatures ranging from 273K to 333K at a constant current density of 8 mA.cm-2. It was observed that kinetic results were found to be increasing linearly with the decrease in temperature.


Shukla V.D.,BJR Government Degree College | Jyothi V.J.,Rbvrr Womens College | Anjaneyulu C.,Osmania University
Research Journal of Pharmaceutical, Biological and Chemical Sciences | Year: 2014

The kinetics of anodic oxidation of Zircaloy-4 in 0.1M sulphamic acid have been studied under galvanostatic conditions at a current density of 8mA.cm-2 and at room temperature (300K). The conventional plots of formation voltage vs. time and reciprocal capacitance vs. time were found to be non-linear. But with the addition of a millimole (mM) of sodium phosphate to 0.1M sulphamic acid, the conventional plots have become linear even upto break down voltage. This marked improvement in the kinetics can be attributed to the incorporation of phosphate ion into the oxide film. This was confirmed by radiotracer techniques using 32P isotope. The uptake and distribution of 32PO4 3- content in the film has suggested a mechanism for the growth of oxide film via interstitial movement of oxide ions. Migration of anion impurities from one layer to another layer in the oxide film has also been established by transferring the specimen from active to inactive solution of the electrolyte and vice versa and thinning subsequently.


Anuradha G.H.,Rbvrr Womens College | Chandra Pal A.V.,Osmania University
E-Journal of Chemistry | Year: 2011

The ligand N(2-benzimidazolyl)acetylacetohydrazone (BAAH) have been synthesized and characterized. Coordination complexes of Cr(III), Mn(II) and Fe(III) have been synthesized with the ligand BAAH. These complexes were characterized on the basis of analytical, conductance, thermal, magnetic data and infrared and electronic spectral data. The ligand BAAH is behaving as a neutral tridentate NNO donar employing two azomethine nitrogens (ring and side chain) and carbonyl oxygen. The ligand and it's metal complexes were tested for anti microbial activity on the gram positive S. Aureus, E. coli and Proteus.


Jyothi V.J.,Rbvrr Womens College | Anjaneyulu Ch.,Osmania University
Journal of the Indian Chemical Society | Year: 2013

Anodization of Zircaloy-4 in 0.1 M L-ascorbic acid has been carried out. Kinetics of anodic oxidation of Zircaloy-4 has been studied at a constant current density of 8 mA.cm-2 and at room temperature. The plots of formation voltage vs time, reciprocal capacitance vs time and reciprocal capacitance vs formation voltage were drawn. From these plots, formation rate, current efficiency and differential field were calculated. The addition of solvent (ethylene glycol) showed better kinetic results for 20, 40, 60 and 80% aquo-glycolic media, the dielectric constant values are low leading to the marked improvement in the kinetics. The surface morphology of the anodic films was also studied by Scanning Electron Micrographs (SEM).


Ushaiah B.,Osmania University | Leela D.S.,Osmania University | Ravi M.,Osmania University | Anupama B.,Rbvrr Womens College | And 2 more authors.
Journal of Fluorescence | Year: 2014

Mixed-ligand Cu(II), Co(II) complexes of formulae [Co(NSALT)(A.A)(H2O)](1), [Co(OHAPT)(A.A)H2O](2), and [Cu(ESALT)(ABPH)H2O] (3) were obtained by refluxing methanol solutions of copper, cobalt chlorides with the appropriate ligands. The complexes were characterized by the ESI-MASS, vibrational spectroscopy (Fourier transform-IR), 1H-NMR spectroscopy, UV-vis spectroscopy, TGA, ESR, SEM and powder XRD. The preliminary DNA-binding activity of the complexes was studied by recording electronic absorption spectra of the complexes in presence of CT-DNA. The binding constants of three complexes towards calf thymus DNA (CT-DNA) [1.2×104 M-1 for 1, 2.5×104 M-1 for 2, and 3.0×104 M-1 for 3] indicate strong interaction of 3. Changes in the fluorescence of ethidium bromide in the presence of DNA suggest intercalation into or electrostatic interactions with CT DNA. The quenching constants, KSV towards-DNA calculated through fluorescence spectra are 2.9×104 M-1for 1, 1.8×104 M-1 for 2, and 3.2×104 M-1 for 3. Docking studies on DNA complexes confirm the binding of 1 and 2 in the major groove of CT-DNA (CTP-1 Endonuclease). Moreover, the antibacterial effect of 1-3 against the five bacterial species was evaluated. The metal complexes have cleavage affinity towards PBR322 plasmid. Furthermore, the antioxidant activities of the complexes were determined by DPPH scavenging activity method. © 2014 Springer Science+Business Media New York.


Jeevana Jyothi V.,RBVRR Womens College | Anjaneyulu C.,Osmania University
Research Journal of Pharmaceutical, Biological and Chemical Sciences | Year: 2015

Anodization of Zircaloy-2 in 0.1M L-Ascorbic acid has been carried out. Kinetics of anodic oxidation of Zircaloy-2 has been studied at a constant current density of 8 mA.cm-2 and at room temperature. The plots of formation voltage vs. time, reciprocal capacitance vs. time and reciprocal capacitance vs. formation voltage were drawn. From these plots, formation rate, current efficiency and differential field were calculated. The Addition of Solvent (Ethylene glycol) showed better kinetic results. For 20%, 40%, 60% and 80% aquo-glycolic media, the dielectric constant values are low leading to the marked improvement in the kinetics. The surface morphology of the anodic films was also studied by Scanning Electron Micrographs (SEM).

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