Polyelectrolyte - Polyampholytes

Polyelectrolytes which bear both cationic and anionic repeat groups are called polyampholytes. The competition between the acid-base equilibria of these groups leads to additional complications in their physical behavior. These polymers usually only dissolve when there is sufficient added salt, which screens the interactions between oppositely charged segments. All proteins are polyampholytes, as some amino acids tend to be acidic while others are basic.