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Quantifying the Binding Interactions Between Cu(II) and Peptide Residues in the Presence and Absence of Chromophores
Published on: April 5, 2022
Studies on the behaviour of beta-ethylthioethylenethioglycollate in aqueous Ni(II) and Cu(II) solutions
L R Pitombo1, M P Peters, M do Carmo Medeiros
1Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, São Paulo, Brasil.
Abstract:
The stability constants of the 1:1 and 1:2 complexes of nickel and copper(II) with beta-ethylthioethylenethioglycollic acid have been determined at 25 degrees at ionic strength 1.0 (NaClO(4)). The values for the nickel complexes are K(1) = 1.11 +/- 0.06 x 10(2) (spectrophotometrically) or 1.25 +/- 0.11 x 10(2) (potentiometrically) and K(2) = 3.04 +/- 0.24 x 10(2) (potentiometrically). The corresponding values for the copper complexes are K(1) = 1.27 +/- 0.02 x 10(3) or 1.28 +/- 0.03 x 10(3) and K(2) = 7.29 +/- 0.30 x 10(2).
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