Synthesis, acid-base properties and preliminary cell compatibility evaluation of amphoteric poly(amido-hydrazine)s

Amphoteric poly(amido-hydrazine)s (PAHYs) were obtained by hydrogen-transfer polyaddition of hydrazine, 1,2-dimethylhydrazine and 1,1- dimethylhydrazine to 2,2-bisacrylamidoacetic acid. These polymers were studied for biomedical applications, such as degradability in water solution, acid–base properties, and cell toxicity. They degraded rapidly in aqueous media under physiological conditions, their molecular weight was reduced to about one-fourth, that of the original polymer in less than two days. They exhibited a typical polyelectrolyte behavior with isoelectric points between 4 and 5 and are prevailingly anionic in the blood. In preliminary cell toxicity essays they proved to be remarkably biocompatible, comparable in this respect to amphoteric poly(amido-amine)s (PAAs), and much less toxic than poly-L-lysine and polyethylenimine.