title: New biodegradable hydrogels based on an acryloylated polyaspartamide cross-linked by gamma irradiation.
abstract: Alpha, beta-poly(N-2-hydroxyethyl)-DL-aspartamide (PHEA), a synthetic biocompatible macromolecule, was functionalized with glycidyl methacrylate (GMA) in order to introduce in its side chains residues having double bonds and ester groups. The copolymer (PHG), obtained from PHEA and GMA, had a degree of derivatization of 29 mol%. PHG aqueous solutions are cross-linked by gamma radiation at 0 degrees C either in the presence or absence of N,N'-methylenebisacrylamide (BIS) giving rise to new hydrogel systems. In both cases gelation occurs at quite low doses (0.26 and 0.4 kGy, respectively). The obtained networks were characterized by FT-IR spectrophotometry which confirmed that the cross-linking process involves the vinyl groups of the polymer chains. Swelling measurements evidenced the high affinity of aqueous media at different pH-values towards PHG hydrogels. The sol fractions of the irradiated samples, properly purified, were characterized by FT-IR and 1H-NMR analyses and reduced viscosity measurements. Finally, in vitro chemical or enzymatic hydrolysis studies suggested that the prepared samples undergo a partial degradation at pH 1 and 10 or after incubation with enzymes such as esterase, pepsin, and alpha-chymotrypsin.
authors.affiliation: Dipartimento di Chimica e Tecnologie Farmaceutiche, Università degli Studi di Palermo, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Giammona
authors.forename: G
authors.initials: G
authors.lastname: Pitarresi
authors.forename: G
authors.initials: G
authors.lastname: Cavallaro
authors.forename: G
authors.initials: G
authors.lastname: Spadaro
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis* / Q000737:chemistry* / Q000528:radiation effects; D001673:Biodegradation, Environmental; D003432:Cross-Linking Reagents; D005720:Gamma Rays; D020100:Hydrogels / Q000138:chemical synthesis* / Q000737:chemistry* / Q000528:radiation effects; D006868:Hydrolysis; D066298:In Vitro Techniques; D009682:Magnetic Resonance Spectroscopy; D008422:Materials Testing; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry* / Q000528:radiation effects; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D001672:Biocompatible Materials; D003432:Cross-Linking Reagents; D020100:Hydrogels; D010455:Peptides