Related Experiment Video
Updated: Jun 19, 2026

Easy Manipulation of Architectures in Protein-based Hydrogels for Cell Culture Applications
Published on: August 4, 2017
THE EFFECT OF SALTS ON THE IONISATION OF GELATIN
1Kerckhoff Biological Laboratories, California Institute of Technology, Pasadena.
Abstract:
The effect of the addition of sodium chloride to gelatin solutions is shown from the Donnan relationship to increase the ionisation of the gelatin, the increase produced in acid solutions reaching a maximum at about 1/1000 molar salt concentration. This effect is attributed to the formation of complex ions. From the similar action of calcium and copper chlorides the effective combining power of gelatin for complex positive ion formation is deduced. The bearing of complex ion formation on the zwitter-ionic structure and solubility phenomena of proteins is pointed out.
Related Concept Videos
Ionic Strength: Effects on Chemical Equilibria
In this solution, the primary cation—the calcium...
Common Ion Effect
Ionic Strength: Overview
Determining the pH of Salt Solutions
Ions as Acids and Bases
Salts are ionic compounds composed of cations and anions, either of which may be capable of undergoing an acid or base ionization reaction with water. Aqueous salt solutions, therefore, may be acidic, basic, or neutral, depending on the relative acid-base strengths of the salt’s constituent ions. For example, dissolving the ammonium chloride in water results in its dissociation, as described by the equation:
Electrolytes: van't Hoff Factor

