A dermatological composition comprising a salt of a cation and an anion. The cation is derived from a monomeric or polymeric molecule that will generate an amidine moieity, a guanidine moieity or a biguanide moieity. The anion is derived from a monomeric or polymeric molecule that will generate a carboxylic acid moieity. The composition may be prepared by a metathesis or acid-base reaction.