[Potentiometric titration in biological studies]

The employment of the potentiometric titration method for determination of the nature and concentration of ionized groups in synthetic polyelectrolytes, biopolymers and in membrane fragments of the cell has been considered. The interpretation of the results of potentiometric investigations in the biological system is complicated because of a neglection of the electrostatic factor and differentiation of molecular and supramolecular, structural changes affecting the availability of ionogenic groups. The method, however, provides an important information concerning the character and, particularly, the mechanisms of structural changes in biosystems and in their components under the influence of different factors.