Spectroscopic Analysis of Au-Cu Alloy Nanoparticles of Various Compositions Synthesized by a Chemical Reduction Method

Au-Cu alloy nanoparticles were synthesized by a chemical reduction method. Five samples having different compositions of Au and Cu (Au-Cu 3 : 1, Au-Cu 2 : 1, Au-Cu 1 : 1, Au-Cu 1 : 2, and Au-Cu 1 : 3) were prepared. The newly synthesized nanoparticles were characterized by electronic absorption, fluorescence, and X-ray diffraction spectroscopy (XRD). These alloy nanoparticles were also analyzed by SEM and TEM. The particle size was determined by SEM and TEM and calculated by Debye Scherrer’s equation as well. The results revealed that the average diameter of nanoparticles gets lowered from 80 to 65 nm as the amount of Cu is increased in alloy nanoparticles. Some physical properties were found to change with change in molar composition of Au and Cu. Most of the properties showed optimum values for Au-Cu alloy nanoparticles of 1 : 3. Cu in Au-Cu alloy caused decrease in the intensity of the emission peak and acted as a quencher. The fluorescence data was utilized for the evaluation of number of binding sites, total number of atoms in alloy nanoparticle, binding constant, and free energy of binding while morphology was deduced from SEM and TEM

Redox Behavior of Anticancer Chalcone on a Glassy Carbon Electrode and Evaluation of its Interaction Parameters with DNA

The interaction of anticancer chalcone [AMC, 1-(4′-aminophenyl)-3-(4-N,N-dimethylphenyl)-2-propen-1-one] with DNA has been explored using electrochemical, spectroscopic and viscometric techniques. A shift in peak potential and decrease in peak current were observed in cyclic voltammetry and hypochromism accompanied with bathochromic shift were noticed in UV-Vis absorption spectroscopy. These findings were taken as evidence for AMC –DNA intercalation. A binding constant (K) with a value of 6.15 × 105 M−1 was obtained from CV data, which was also confirmed by UV-Vis absorption titration. Moreover, the diffusion coefficient of the drug with and without DNA (Db and Du), heterogeneous electron transfer rate constant (ko) and electron affinity (A) were also calculated from electrochemical data

Electrochemical behavior of 1-ferrocenyl-3-phenyl-2-propen-1-one on glassy carbon electrode and evaluation of its interaction parameters with DNA

The electrochemical behavior of 1-ferrocenyl-3-phenyl-2-propen-1-one (ferrocenylone) and its interaction with DNA was studied by a glassy carbon electrode using cyclic voltammetry (CV) technique. The results from CV were supported by UV-Visible spectroscopy performed under the similar conditions. The positive peak potential shift in CV and the bathochromic shift in the UV-Vis absorption spectra suggested an intercalative mode of binding. The binding constant (K = 1.39 ± 0.02 × 10(4) mol-1 L) and the binding site size (0.53 bp) were obtained from voltammetric data which leads to a standard Gibbs free energy change (ΔGº= -RT lnK) of -23.64 kJ mol-1 and hence indicated the spontaneity of the binding interaction. The values of binding constants obtained from UV-Vis absorption and CV measurements, 1.26 ± 0.01 × 10(4) and 1.39 ± 0.02 × 10(4) mol-1 L respectively, were in close agreement

Synthesis, spectroscopic characterization, X-ray structure and evaluation of binding parameters of new triorganotin(IV) dithiocarboxylates with DNA

Three new triorganotin(IV) dithiocarboxylates (1-3) with general formula R(3)SnL, where R=C(4)H(9) (1), C(6)H(11) (2), C(6)H(5) (3) and L=4-(4-nitrophenyl)piperazine-1-carbodithioate, have been synthesized and characterized by elemental analysis, Raman, FT-IR, multinuclear NMR ((1)H, (13)C and (119)Sn) and mass spectrometry. The crystal structure of complex 3 confirmed distorted trigonal-bipyramidal geometry around Sri atom. The interaction of compounds 1-3 with DNA was investigated by cyclic voltammetry (CV) and UV-vis spectroscopy. The positive peak potential shift in CV and hypochromic effect in spectroscopy evidenced intercalative mode of interaction. The results indicate that the binding affinity varies in this sequence: 1 > 3 > 2. (C) 2009 Published by Elsevier Masson SAS

Diorganotin(IV) derivatives of ONO tridentate Schiff base:Synthesis, crystal structure, in vitro antimicrobial, anti-leishmanial and DNA binding studies

Six new diorganotin(IV) derivatives of N'-(2-hydroxybenzylidene)formohydrazide (H2L) with general formula R2SnL, where R = Ph (1), Me (2), Bu (3), Oct (4), t-Bu (5), Et (6), and L = [OC6H4CHNNCHO] have been synthesized and characterized by different analytical techniques. Crystal structure of Me2SnL (2) authenticated distorted square-pyramidal geometry around the Sn atom. The CV and UV-Vis spectroscopic data indicated intercalation of complexes into DNA with binding affinity varying in the sequence: 3 (1.69 x 10(4) M-1) > 1 (1.10 x 10(4) M-1) > 2 (9.61 x 10(3) M-1). Some of these compounds were found to be good antibacterial, antifungal and leishmanicidal agents. (C) 2010 Elsevier Masson SAS. All rights reserved

Organotin(IV) 4-nitrophenylethanoates:Synthesis, structural characteristics and intercalative mode of interaction with DNA

Four new organotin(IV) carboxylates, [Bu(2)SnL(2)] (1), [Et(2)SnL(2)] (2), [Bu(3)SnL](n) (3), [Me(3)SnL](n) (4), where L = 4-nitrophenylethanoates, were synthesized and characterized by elemental analysis, FT-IR and multinuclear NMR ((1)H and (13)C). Spectroscopic results authenticated the coordination of ligand to the organotin moiety via COO group while X-ray single crystal analysis revealed bidentate chelating mode of coordination of ligand in complex 2 and a bridging behavior in complexes 3 and 4. Cyclic voltammetric ( CV) technique was used to evaluate the electrochemical, kinetic and thermodynamic parameters of complexes 1-4, interacting with DNA. The linearity of the plots between the peak current (I) and the square root of the scan rate (nu(1/2)) indicated the electrochemical processes to be diffusion controlled. The diffusion coefficients of the free (D(f)) and DNA bound forms (D(b)), standard rate constants (ks) and charge transfer coefficients (alpha) were determined by the application of Randle-Sevcik, Nicholson and Kochi equations. Furthermore, the binding constants evaluated from voltammetric data revealed the following increasing order of binding strength: 2 <1 <4 <3. For 1 and 2, the activity against prostate cancer cell lines (PC-3) was found consistent with the order obtained from voltammetric behavior. (C) 2009 Elsevier B.V. All rights reserved