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.