Crosslinked α,β-polyasparthydrazide hydrogels: effect of crosslinking degree and loading method on cytarabine release rate

Abstract

α,β-Polyasparthydrazide (PAHy) was crosslinked by glutaraldehyde to form water-swellable polymers possessing a three dimensional molecular network. The glassy polymeric material was loaded with cytarabine and shaped as micromatrices. The drug was incorporated both during crosslinking reaction by dissolving it in the reaction medium and after crosslinking by a soaking technique. The polymer network structure was characterized by dimensional analysis, swelling measurements, scanning electron microscopy and X-ray analysis. Biological trials have shown the absence of toxicity after subcutaneous implantation of these materials in laboratory animals. Drug release from the micromatrices loaded by the soaking method takes place in less than 4 h. On the contrary, samples loaded during crosslinking reaction release 40% of cytarabine in 20 days.