title: The Ca(2+)-EDTA chelation as standard reaction to validate Isothermal Titration Calorimeter measurements (ITC).
abstract: A study about the suitability of the chelation reaction of Ca(2+)with ethylenediaminetetraacetic acid (EDTA) as a validation standard for Isothermal Titration Calorimeter measurements has been performed exploring the common experimental variables (buffer, pH, ionic strength and temperature). Results obtained in a variety of experimental conditions have been amended according to the side reactions involved in the main process and to the experimental ionic strength and, finally, validated by contrast with the potentiometric reference values. It is demonstrated that the chelation reaction performed in acetate buffer 0.1M and 25°C shows accurate and precise results and it is robust enough to be adopted as a standard calibration process.
authors.affiliation: Departament de Química Analítica i Institut de Biomedicina (IBUB), Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain. Electronic address: crafols@ub.edu.
authors.forename: Clara
authors.initials: C
authors.lastname: Ràfols
authors.affiliation: Departament de Química Analítica i Institut de Biomedicina (IBUB), Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Bosch
authors.affiliation: Unitat de Polimorfisme i Calorimetria, Centres Científics i Tecnològics, Universitat de Barcelona, Baldiri Reixac 10, 08028 Barcelona, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Barbas
authors.affiliation: Unitat de Polimorfisme i Calorimetria, Centres Científics i Tecnològics, Universitat de Barcelona, Baldiri Reixac 10, 08028 Barcelona, Spain.
authors.forename: Rafel
authors.initials: R
authors.lastname: Prohens
keywords: Energetics of Ca(2+)–EDTA chelation; ITC; ITC chemical calibration; ITC measurements validation; Isothermal Titration Calorimeter