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Updated: Aug 18, 2026

Quantifying the Binding Interactions Between Cu(II) and Peptide Residues in the Presence and Absence of Chromophores
Published on: April 5, 2022
[Use of dinitrophenols in ion-pair extraction spectrophotometry of cationic tensides]
1Univerzita Karlova v Praze, Farmaceutická fakulta v Hradci Králové, Katedra biofyziky a fyzikální chemie. kubicek@faf.cuni.cz
Abstract:
The application of 2,4-dinitrophenol and 2,6-dinitrophenol as reagents for a ion pair extraction spectrophotometry was tested. The ion pair extraction spectrophotometry experiments were carried out using a simplified procedure (test tube method). Four cationic tensides were used as model analytes. After the optimal conditions of the assay were being determined, the influence of the concentration excess of the reagents on the absorbance of the chloroform extract was investigated. Calibration curves were constructed; an estimation of limits of quantitation was performed and apparent molar absorption coefficients were determined. The obtained results show that both investigated dinitrophenols are suitable for the studied purpose.
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