scholarly journals Stability Constants of Mixed Ligand Complexes of Cu(II) and Ni(II) with Some Amino Acids and Phosphates

2011 ◽  
Vol 8 (s1) ◽  
pp. S404-S408 ◽  
Author(s):  
Aruna Adam ◽  
Suman Verma ◽  
Gita Seth
Keyword(s):  
Amino Acids ◽  
Formation Constants ◽  
Ternary Complexes ◽  
Mixed Ligand ◽  
Binary And Ternary Complexes ◽  
Titration Curves ◽  
Ternary Metal ◽  
Ternary Metal Complexes ◽  
Titration Technique ◽  
Secondary Ligand

The binary and ternary metal complexes of Cu(II) & Ni(II) with some amino acids (leucine, isoleucine & serine) as primary ligand and pyrophosphate (PP), adenosine-5´-triphosphate (ATP), as secondary ligand have been studied potentiometrically at 35 °C and a constant ionic strength (1.0 mol dm-3KNO3). The formation of various binary and ternary complexes has been inferred from the corresponding titration curves. The Irving & Rossotti titration technique has been applied to determine the formation constants corresponding to various complexation equilibria.

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.

scholarly journals Stability Constants of Mixed Ligand Complexes of Nickel(II) with Adenine and Some Amino Acids

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Naciye Türkel
Keyword(s):  
Aqueous Solution ◽  
Amino Acids ◽  
Ternary Complex ◽  
Coordination Complexes ◽  
Ternary Complexes ◽  
Mixed Ligand ◽  
Relative Stabilities ◽  
Binary And Ternary Complexes ◽  
Binary Complexes ◽  
Essential Trace Elements

Nickel is one of the essential trace elements found in biological systems. It is mostly found in nickel-based enzymes as an essential cofactor. It forms coordination complexes with amino acids within enzymes. Nickel is also present in nucleic acids, though its function in DNA or RNA is still not clearly understood. In this study, complex formation tendencies of Ni(II) with adenine and certain L-amino acids such as aspartic acid, glutamic acid, asparagine, leucine, phenylalanine, and tryptophan were investigated in an aqueous medium. Potentiometric equilibrium measurements showed that both binary and ternary complexes of Ni(II) form with adenine and the above-mentioned L-amino acids. Ternary complexes of Ni(II)-adenine-L-amino acids are formed by stepwise mechanisms. Relative stabilities of the ternary complexes are compared with those of the corresponding binary complexes in terms ofΔlog10⁡K,log10⁡X, and % RS values. It was shown that the most stable ternary complex is Ni(II):Ade:L-Asn while the weakest one is Ni(II):Ade:L-Phe in aqueous solution used in this research. In addition, results of this research clearly show that various binary and ternary type Ni(II) complexes are formed in different concentrations as a function of pH in aqueous solution.

Mixed Ligand Derivatives of 1: 1 Th(IV)—DTPA Chelate with Some Hydroxy Acids(H)

1975 ◽  
Vol 30 (9-10) ◽  
pp. 751-754 ◽  
Author(s):  
O. P. Pachauri ◽  
J. P. Tandon
Keyword(s):  
Formation Constants ◽  
Bidentate Ligand ◽  
Mixed Ligand ◽  
Bidentate Ligands ◽  
Hydroxy Acids ◽  
Titration Curves ◽  
Hydroxy Quinoline ◽  
Derivatives Of ◽  
Sulphosalicylic Acid ◽  
Secondary Ligand

Studies of the interaction between 1:1 Th(IV)-DTPA chelate (where DTPA = diethylenetriaminepentaacetic acid) with certain bidentate ligands, such as salicylic acid (SA), 5-sulphosalicylic acid (SSA) and 8-hydroxy quinoline-5-sulphonic acid (HQSA) have been carried out potentiometrically. The nature of the titration curves indicates that the bidentate ligand is added stepwise to the initially formed metal diethylenetriaminepentaacetate. The formation constants (log KMAB) of the resulting 1:1:1 mixed ligand derivatives have been determined at 30 ± 1 °C and μ = 0.1 (KNO3). The order of stability in terms of the secondary ligand has been found to be SA > SSA > HQSA.

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.

scholarly journals Stability Constants of Mixed Ligand Complexes of Transition Metal(II) Ions withN-(2-Hydroxy-1-naphthylidene)-2,6-diisopropylaniline as Primary Ligand and N-(2-Hydroxybenzylidene)-2,3-dimethylaniline as Secondary Ligand

2011 ◽  
Vol 8 (1) ◽  
pp. 123-126
Author(s):  
A. K. Mapari ◽  
K. V. Mangaonkar
Keyword(s):  
Transition Metal ◽  
Stability Constants ◽  
Ternary Complexes ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Water Medium ◽  
Binary And Ternary Complexes ◽  
Secondary Ligand

Binary and ternary complexes of the type M-Y and M-X-Y [M = Co(II), Ni(II), Cu(II) and Zn(II); X = N-(2-hydroxy-1-naphthylidene)-2,6-diisopropylaniline and Y =N-(2-hydroxybenzylidene)-2,3-dimethylaniline] have been examined pH-metrically at 27±0.5°C and µ = 0.1 M in 75: 25% (v/v) 1,4-dioxne-water medium. The logarithms of the values of stability constants for binary (M-Y) and for ternary (M-X-Y) systems were calculated.

scholarly journals Stability Constants of Mixed Ligand Complexes of Transition Metal(II) ions with N-(2-hydroxybenzylidene)-2,3-dimethylaniline as Primary Ligand and N-(2-hydroxy-1-naphthylidene)-4-nitroaniline as Secondary Ligand

2011 ◽  
Vol 8 (2) ◽  
pp. 859-862 ◽  
Author(s):  
A. K. Mapari ◽  
K. V. Mangaonkar
Keyword(s):  
Ionic Strength ◽  
Transition Metal ◽  
Stability Constants ◽  
Ternary Complexes ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Water Medium ◽  
Binary And Ternary Complexes ◽  
The Stability ◽  
Secondary Ligand

Binary and ternary complexes of the type M-Y and M-X-Y [M=Co(II), Ni(II), Cu(II) and Zn(II); X=N-(2-hydroxybenzylidene)-2,3-dimethylaniline and Y =N-(2-hydroxy-1-naphthylidene)-4-nitroaniline] have been examined pH-metrically at 27±0.5 °C and at constant ionic strength, μ=0.1 M (KCl) in 75:25(v/v) 1,4-dioxne-water medium. The stability constants for binary (M-Y) and ternary (M-X-Y) systems were calculated.

Differential pulse polarographic studies on simple and mixed ligand complexes of Cd(II) with diaminopropane and adipate ligands

1990 ◽  
Vol 55 (10) ◽  
pp. 2381-2389
Author(s):  
Hamada M. Killa ◽  
El-Sayed M. Mabrouk ◽  
Abdel Fattah A. Abdel Fattah
Keyword(s):  
Differential Pulse ◽  
Formation Constants ◽  
Ternary Complexes ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Mixed Complexes ◽  
Diffusion Controlled ◽  
And Diffusion ◽  
Secondary Ligand

The composition, stability and equilibria of ternary complexes of Cd(II) with adipate (Adp) as primary ligand and 1,3-diaminopropane (DAMP) as secondary ligand have been studied using differential pulse (d.p.) polarography. The results reveal the presence of three ternary complexes with stoichiometries 1:1:1, 1:1:2, and 1:2:1. Also, the composition and stability of binary species have been determined. The reduction of simple and mixed ligand complexes is reversible and diffusion controlled. The formation constants of mixed complexes were calculated and compared with the observed values.

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 Stability Constants of Mixed Ligand Complexes of Transition Metal(II) Ions with Salicylidene-4-methoxyaniline as Primary Ligand and 5-Bromosalicylidene-4-nitroaniline as Secondary Ligand

2011 ◽  
Vol 8 (4) ◽  
pp. 1765-1769 ◽  
Author(s):  
N. G. Nadkarni ◽  
K. V. Mangaonkar
Keyword(s):  
Ionic Strength ◽  
Stability Constants ◽  
Ternary Complexes ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Water Medium ◽  
Binary And Ternary Complexes ◽  
Binary Complexes ◽  
The Stability ◽  
Secondary Ligand

Binary and ternary complexes of the type M-Y and M-X-Y [M = Mn(II), Ni(II), Cu(II) and Zn(II); X = salicylidene-4-methoxyaniline and Y=5-bromosalicylidene-4-nitroaniline] have been examined pH-metrically at 27±0.5 °C and at constant ionic strength, μ= 0.1 M (KCl) in 75 : 25(v/v) 1,4-dioxne-water medium. The stability constants for binary (M-Y) and ternary (M-X-Y) systems were calculated. The relative stability (Δ log KT) values of the ternary complexes with corresponding binary complexes for all the metal(II) ions in the present study found to be negative indicating that ternary 1:1:1 (M-X-Y) complexes are less stable than binary 1:1 (M-Y) complexes. In the ternary system studied, the order of stability constants of mixed ligand complexes with respect to the metal ions was found to be Cu(II) > NI(II) > Mn(II) > Zn(II); which is same as in the corresponding binary (M-Y) systems.

Potentiometric Studies on Stepwise Mixed Ligand Complex Formation

1970 ◽  
Vol 25 (1) ◽  
pp. 22-26 ◽  
Author(s):  
G. Sharma ◽  
J. P. Tandon
Keyword(s):  
Complex Formation ◽  
Metal Ion ◽  
Mixed Ligand Complex ◽  
Iminodiacetic Acid ◽  
Formation Constants ◽  
Ternary Complexes ◽  
Mixed Ligand ◽  
Molar Ratio ◽  
Ligand Complex ◽  
Secondary Ligand

Stepwise mixed ligand complex formation is observed in the systems containing metal ion, iminodiacetic acid (IMDA) as primary ligand and one of the diamines, such as ethylenediamine (en), 1,2-propanediamine (1,2-pn) and 1,3-propanediamine (1,3-pn) as secondary ligands. Potentionmetric titrations indicate the formation of ternary complexes having a 1:1:1 molar ratio of metal ion to iminodiacetic acid to the secondary ligand. Initially, metal-IMDA (1:1) complex is formed in the lower buffer region prior to the formation of the ternary complex and the addition of the secondary ligand takes place only after the combination with the primary ligand is complete. Formation constants (log KMAB) of the ternary complexes have been calculated and the probable reaction mechanism is suggested. The order of stability in terms of metal ion has been found to be Cu (II) > Ni (II) >Zn (II) >Cd (II) and in terms of secondary ligand as 1,2-pn>en>1,3-pn.

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