scholarly journals Interactions of some metal ions with Nitrogenous bases present in Nucleotides

2007 ◽  
Vol 4 (3) ◽  
pp. 420-424
Author(s):  
Baghdad Science Journal
Keyword(s):  
Ionic Strength ◽  
Nucleic Acid ◽  
Metal Ions ◽  
Stability Constants ◽  
Uranyl Ions ◽  
Acidity Constants ◽  
Stability Constants Of Complexes ◽  
Complexes With Metal Ions

Acidity constants at 30co and 0.125 ionic strength have been determined for the Nitrogous bases of nucleic acid; cytocine, uarcil and thymine, and found to be 3.55 x10-19 , 1.44 x10 -19 and 7.24 x10 -20 respectively. Stability constants of these bases with Thorium and uranyl ions have been determined. Results showed that metal ions Thorium and uranyl ions behave as hard acids and the nitrogenum bases behave as Hard bases according to Pearson's definition .Hardness – softness parameters for these ligands were calculated ,stability constants of complexes with metal ions could be arranged as follows :- Cytosine > Uracil > Thymine .

scholarly journals Stability Constants of Lanthanide Metal Ions Chelates with Substituted Pyrazoles in Different Solvents

2011 ◽  
Vol 8 (1) ◽  
pp. 131-136 ◽  
Author(s):  
G. H. Murhekar ◽  
A. R. Raut ◽  
R. S. Sonone
Keyword(s):  
Ionic Strength ◽  
Metal Ions ◽  
Stability Constants ◽  
Water Mixture ◽  
Solvent Medium ◽  
Acetone Water ◽  
Lanthanide Metal ◽  
Substituted Pyrazoles ◽  
Metal Ligand

The reaction of Pr (III) and Nd (III) metal ions with some substituted pyrazoles, at 0.1M ionic strength and at 30 ± 0.10C in 70% acetone-water mixture and 70% propanol-water mixture have been studied pH-metrically. The data obtained were used to estimate the values of proton-ligand (pK) and metal-ligand (logK) stability constants in different solvents. It is observed that the pK and logK values in 70% propanol-water mixture are grater than in 70% acetone -water mixture. Pr (III) and Nd (III) metal ions formed 1:1 and 1:2 complexes with all the ligands in both solvent medium.

The stability constants of ethylenediphosphinetetraacetate complexes

1982 ◽  
Vol 47 (4) ◽  
pp. 1078-1085 ◽  
Author(s):  
Jana Podlahová ◽  
Jaroslav Podlaha
Keyword(s):  
Aqueous Solutions ◽  
Metal Ions ◽  
Stability Constants ◽  
Metal Ion ◽  
Computer Programs ◽  
Data Treatment ◽  
Relative Affinity ◽  
Stability Constants Of Complexes ◽  
Soft Metal ◽  
The Stability

The stability constants of complexes formed by the anions of ethylenediphosphinetetraacetic acid and the metal ions Cu(I), Ag(I), Ca(II), Mn(II), Fe(II), Co(II), Ni(II), Zn(II), Cd(II), Hg(II), Pb(II) and La(III) were determined by various methods (mainly potentiometry and UV-VIS spectrophotometry), followed by data treatment using standard computer programs. The type and stability of the complexes formed depend mostly on the relative affinity of the particular metal ion for the two donor groups of the ligand. Unlike EDTA, the ligand is highly selective for soft metal ions, whose complexes are very stable even in strongly acidic aqueous solutions.

Synthesis of some salicylic acid derivatives and studies of their interaction with uranyl ion

1991 ◽  
Vol 56 (7) ◽  
pp. 1446-1453 ◽  
Author(s):  
Evgenija A. Djurendić ◽  
Terézia M. Surányi ◽  
Dušan A. Miljković
Keyword(s):  
Salicylic Acid ◽  
Stability Constants ◽  
Aqueous Ethanol ◽  
Continuous Variation ◽  
Acidity Constants ◽  
Stability Constants Of Complexes ◽  
Salicylic Acid Derivatives ◽  
Method Of Continuous Variation ◽  
The Stability ◽  
Derivatives Of

Some unsubstituted and substituted bis-derivatives of salicylic acid have been synthesized and their acidity constants determined spectrophotometrically in 61.10% aqueous ethanol. The stability constants of complexes these compounds from with UO22+-ion were determined spectrophotometrically using the method of continuous variation under following conditions: pH 3.58 and 3.98, 61.10% aqueous ethanol, μ = 0.5 (LiCl), 25 ± 1 °C.

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