1. Chemical properties
Tris (trimethylolaminomethane) is a weak base with a pKa value between 8.0-8.3, which makes it an effective buffer within the physiological pH range. The Tris molecule contains three hydroxyl groups and one amino group, and the presence of these functional groups allows it to ionize in aqueous solutions and accept or release hydrogen ions to maintain pH stability.
2. Buffering
The buffering effect of Tris is mainly based on the shift in its ionization equilibrium. When the concentration of hydrogen ions in the solution increases, Tris can accept additional hydrogen ions, thus preventing a drop in pH. Conversely, when the concentration of hydrogen ions decreases, Tris can release hydrogen ions to maintain a stable pH. This buffering is essential to protect DNA from damage caused by pH changes.
