scholarly journals Potentiometric and UV Spectral Studies of Binary and Ternary Complexes of Some Metal Ions withN-Acetylcysteine and Amino Acids

2009 ◽  
Vol 6 (s1) ◽  
pp. S117-S122 ◽  
Author(s):  
Shaesta Quyoom ◽  
Badr-Ud-Din Khan
Keyword(s):  
Amino Acids ◽  
Metal Ions ◽  
Aqueous Medium ◽  
Dissociation Constants ◽  
Formation Constants ◽  
Ternary Complexes ◽  
Acid Dissociation ◽  
Spectral Studies ◽  
Binary And Ternary Complexes ◽  
Structural Nature

The formation constants of the binary 1:1 and 1:2 complexes of Cu(II), Zn(II), Cd(II), Hg(II), and Pb(II) withN-acetylcysteine (NAC) and 1:1:1 ternary complexes of the said metal ions with NAC as a primary ligand and some biologically important amino acids as secondary ligands have been determined potentiometrically in aqueous medium. Acid dissociation constants of the ligands used and the formation constants of the binary and the ternary complexes were determined at 25 °C and in ionic strength I=0.1 mol dm-3(KNO3).The formation constants of the 1:1 complexes were found to be higher than 1:2 complexes and the metal ions follow the order Hg(II) >Cu(II) >Cd(II) >Zn(II). In addition UV-spectral studies of the NAC-Metal (II) complexes have also been conducted at appropriate pH values to give further information about the structural nature of NAC- Metal (II) complexes in aqueous medium.

Equilibrium Studies of Binary and Ternary Complexes of Palladium(II) Involving Amino Acids

1993 ◽  
Vol 58 (5) ◽  
pp. 1103-1108 ◽  
Author(s):  
Mohamed M. Shoukry ◽  
Eman M. Shoukry
Keyword(s):  
Amino Acids ◽  
Relative Stability ◽  
Ternary Complex ◽  
Formation Constants ◽  
Ternary Complexes ◽  
Conductivity Measurements ◽  
Equilibrium Studies ◽  
Binary And Ternary Complexes ◽  
Binary Complexes

The formation constants of the binary and ternary complexes of palladium(II) with diethylenetriamine and amino acids as ligands have been determined potentiometrically at 25 °C in 0.1 M NaNO3 solution. The relative stability of each ternary complex was compared with that of the corresponding binary complexes in terms of ∆logK values. The mode of chelation was ascertained by conductivity measurements.

A stability and equilibrium study on Cd – salicylidene tris(hydroxymethyl) methylamine – chloride binary and ternary complexes

1992 ◽  
Vol 70 (3) ◽  
pp. 877-879
Author(s):  
Refat Abdel-Hamid ◽  
Mohamed T. El-Haty
Keyword(s):  
Binary System ◽  
Aqueous Medium ◽  
Chloride Ion ◽  
Formation Constants ◽  
Ternary Complexes ◽  
Binary And Ternary Complexes ◽  
Equilibrium Study

Binary and ternary complexes of Cd(II) with salicylidene tris(hydroxymethyl) methylamine and chloride ion at 298 K were studied polarographically at I = 0.1 mol dm−3 NaClO4 in 30% (v/v) DMF – aqueous medium at pH 10.2. The overall formation constants were found to be, for the binary system, log β1 = 3.55 ± 0.03 and log β2 = 5.40 ± 0.07 and, for the ternary one, log β11 = 7.64 ± 0.06 and log β12 = 9.56 ± 0.06. Keywords: formation constants, binary and ternary complexes of Cd(II).

scholarly journals Characterization by Potentiometric Procedures of the Stability Constants of the Binary and Ternary Complexes of Cu(II) and Duloxetine Drug with Amino Acids

2019 ◽  
Vol 2019 ◽  
pp. 1-13
Author(s):  
Amal M. Al-Mohaimeed ◽  
Asma A. Alothman
Keyword(s):  
Amino Acids ◽  
Stability Constants ◽  
Formation Constants ◽  
Ternary Complexes ◽  
Planar Geometry ◽  
Binary And Ternary Complexes ◽  
Mass Spectral ◽  
Binary Complexes ◽  
Potentiometric Titration Method ◽  
The Stability

Potentiometric titration method has been used to define stoichiometries and stability constants of ternary complexes of Cu(II) with duloxetine (D) and some selected amino acids (L). The protonation constants of the ligands and the stability constants of the binary and ternary complexes of Cu(II) with the ligands were calculated from the potentiometric data using the HYPERQUAD program. The formation constants of the complexes formed in aqueous solutions and their concentration distributions as a function of pH were evaluated at 25°C and ionic strength 0.10 mol·L−1 NaNO3. Respective stabilities of ternary complexes have been determined compared with the corresponding binary complexes in terms of Δlog  K and %R.S. values. A novel binary and ternary duloxetine (D) drug with glycine and its Cu(II) complexes has been synthesized and characterized by several spectroscopic methods. Electronic spectra and magnetic susceptibility measurements reveal square planar geometry for both complexes. The elemental analyses and mass spectral data have justified the [Cu(D)(Gly)] and [Cu(D)Cl(H2O)] composition of complexes, where D = duloxetine and Gly = glycine. The EPR spectra of Cu(II) complexes support the mononuclear structures. Thermal properties and decomposition kinetics of Cu(II) complexes are investigated.

scholarly journals Spectrophotometric Microdetermination of Thorium(IV) and Uranium(VI) with Chrome Azurol-S in Presence of Cationic Surfactant

2011 ◽  
Vol 8 (3) ◽  
pp. 1132-1141 ◽  
Author(s):  
A. B. Upase ◽  
A. B. Zade ◽  
P. P. Kalbende
Keyword(s):  
Metal Ions ◽  
Cationic Surfactant ◽  
Bathochromic Shift ◽  
Stoichiometric Composition ◽  
Formation Constants ◽  
Ternary Complexes ◽  
Water Soluble ◽  
Molar Ratio ◽  
Chrome Azurol S ◽  
Binary And Ternary Complexes

Cationic surfactant, cetyldimethylethylammonium bromide (CDMEAB), sensitize the color reactions of Th(IV) and U(VI) with chrome azurol-S(CRAS). Formation of water soluble deeply colored ternary complexes of metal ions show large bathochromic shift. Same stoichiometric composition of ternary complexes with 1:2:4 molar ratio (M-CRAS-CDMEAB) have been observed for both the metal ions and are responsible for enhancement in molar absorptivities and sensitivities at shifted wavelength. The ternary complexes of thorium(IV) and uranium(VI) exhibit absorption maxima at 640 and 620 nm with molar absorptivities 85500 and 69600 L.mol-1.cm-2respectively. Beer’s law were obeyed in concentration range 0.12-0.185 ppm for Th(IV) and 0.13-0.162 ppm for U(VI) in presence of CDMEAB. Conditional formation constants and various analytical parameters have been evaluated and compared the results of binary and ternary complexes. Enhancement in the molar absorptivities in presence of CDMEAB clearly indicated the usefulness of these colored reactions for microdetermination.

scholarly journals Investigation of Extent of Interaction of Thiobarbituric Acid and Two Selected Amino Acids with Three Divalent Metal Ions in Aqueous-organic Medium at Different Temperatures

2019 ◽  
pp. 1-8
Author(s):  
M. A. Oladipo ◽  
K. T. Ishola ◽  
T. A. Ajayeoba
Keyword(s):  
Metal Ions ◽  
Thiobarbituric Acid ◽  
Entropy Change ◽  
Formation Constants ◽  
Ternary Complexes ◽  
Water Mixture ◽  
Divalent Metal Ions ◽  
Binary And Ternary Complexes ◽  
Binary Complexes ◽  
The Difference

The formation constants of binary and ternary complexes of Thiobarbituric acid as primary ligand and L-tyrosine and L-histidine as secondary ligands have been examined in 40% (v/v) ethanol-water mixture at 27oC and 35oC and at ionic strength of 0.02 NaNO3 by potentiometric method. The ligands formed 1:1 binary complexes with the metal ions. The primary and secondary ligands simultaneously coordinated to the metal ions to form 1:1:1 ternary complexes. The difference in stability constants of binary and ternary complexes were determined by DlogK and RS%. Ternary complexes exhibited enhanced stability than the binary complexes. The stability of the complexes decrease with increase in temperature. The thermodynamic parameters such as Gibb’s free energy change (ΔG), entropy change (ΔS) and enthalpy change (ΔH) accompany the interactions were evaluated. The interactions were found to be spontaneous, exothermic, and entropically favoured.

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