Determination of the thermodynamic ionization constants of cefroxadine

The values of the thermodynamic ionization constants of the carboxylic (pK = 3.30 +/- 0.02) and amine (pK = 7.00 +/- 0.06) groups of cefroxadine were determined at 35.0 degrees C using potentiometric data. The apparent ionization constants of these groups were also determined at 35.0 degrees C, and at different values of ionic strength.