title: New hydrogel matrices containing an anti-inflammatory agent. Evaluation of in vitro release and photoprotective activity.
abstract: In the present work. the preparation and characterization of hydrogels based on alpha,beta-polyaspartylhydrazide (PAHy) chemically crosslinked with ethyleneglycol diglycidylether (EGDGE) containing Tolmetin sodium salt, are reported. In particular, these samples have been prepared both as water swellable microparticles and as gels at two different crosslinking degrees. The incorporation of Tolmetin sodium salt in PAHy-EGDGE microparticles has been performed after the crosslinking reaction by a soaking procedure or during the formation of the network. The influence of drug loading procedure on Tolmetin release has been evaluated by performing in vitro release study in simulated gastrointestinal fluids (pH 1.0/6.8) using the pH variation method and in phosphate buffered saline, pH 7.4. PAHy-EGDGE networks containing Tolmetin sodium salt have been also prepared as gels. These have showed a slowed down release as evidenced by in vitro release studies at pH 5.0 and 7.4 using a Franz diffusion cell system and an artificial membrane. Finally, PAHy EGDGE networks provide a pronounced reduction of the photosensitizing activity of Tolmetin, as evidenced by in vitro hemolysis assays.
authors.affiliation: Dipartimento di Chimica e Tecnologie Farmaceutiche, Università di Palermo, Italy. gaegiamm@unipa.it
authors.forename: Giovanna
authors.initials: G
authors.lastname: Pitarresi
authors.forename: Gennara
authors.initials: G
authors.lastname: Cavallaro
authors.forename: Gaetano
authors.initials: G
authors.lastname: Giammona
authors.forename: Guidi Guido
authors.initials: GG
authors.lastname: De
authors.forename: Maria Gabriella
authors.initials: MG
authors.lastname: Salemi
authors.forename: Salvatore
authors.initials: S
authors.lastname: Sortino
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000737:chemistry / Q000493:pharmacokinetics* / Q000494:pharmacology; D018360:Crystallography, X-Ray; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D066298:In Vitro Techniques; D010777:Photochemistry; D014046:Tolmetin / Q000737:chemistry / Q000493:pharmacokinetics* / Q000494:pharmacology
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D014046:Tolmetin