DETERMINATION OF MACROSCOPIC THERMODYNAMIC IONIZATION-CONSTANTS UNDER CONDITIONS OF VARIABLE IONIC-STRENGTH BY AN OPTIMIZATION ALGORITHM

The thermodynamic macroscopic ionization constants of cysteine, penicillamine, 6-amino penicillanic acid and 7-amino cephalosporanic acid were determined at different temperatures by a dynamic method employing potentiometric data obtained at ionic strengths that vary continuously throughout the titration. This method gives thermodynamic pK-values in a single experiment. A computer program has been developed for the titrations. It makes use of an algorithm based on controlled descent. © 1990.