The aim of this study was to prepare and characterize novel hydrogels with polysaccharide-polyaminoacid structure, able to undergo an enzymatic hydrolysis in the colon and potentially useful for treating inflammatory bowel diseases (1131)). Starting materials were methacrylated dextran (DEX-MA) and methacrylated alpha,beta-poly(N-2-hydroxyethyl)-DL-aspartamide (PHM). These polymers were photocrosslinked by exposure of their aqueous solutions at 313 nm without photoinitiators. Different samples, shaped as microparticles, were obtained as a function of polymer concentration and irradiation time. FT-IR analysis confirmed the occurrence of a co-crosslinking between DEX-MA and PHM in all experimental conditions. Size analysis evidenced a narrow particle distribution and swelling studies, performed in twice-distilled water and simulated gastrointestinal fluids, showed a good affinity of these hydrogels towards the aqueous medium. DEX-MA/PHM based hydrogels undergo a negligible chemical hydrolysis, whereas they are partially degraded by dextranase. In vitro biological assays showed cell compatibility of these samples. Beclomethasone dipropionate (BDP), a drug recently proposed for the treatment of 1131) was entrapped into a DEX-MA/PHM based hydrogel and its release was evaluated in the absence or in the presence of dextranase. Obtained release profiles suggest the potential use of BDP loaded DEX-MA/PHM based hydrogels for the treatment of IBD. (c) 2007 Elsevier B.V. All rights reserved.
Photocrosslinking of dextran and polyaspartamide derivatives: A combination suitable for colon-specific drug delivery / Giovanna, Pitarresi; Casadei, Maria Antonietta; Delia, Mandracchia; Paolicelli, Patrizia; Fabio Salvatore, Palumbo; Gaetano, Giammona. - In: JOURNAL OF CONTROLLED RELEASE. - ISSN 0168-3659. - STAMPA. - 119:3(2007), pp. 328-338. [10.1016/j.jconrel.2007.03.005]
Photocrosslinking of dextran and polyaspartamide derivatives: A combination suitable for colon-specific drug delivery
CASADEI, Maria Antonietta;PAOLICELLI, PATRIZIA;
2007
Abstract
The aim of this study was to prepare and characterize novel hydrogels with polysaccharide-polyaminoacid structure, able to undergo an enzymatic hydrolysis in the colon and potentially useful for treating inflammatory bowel diseases (1131)). Starting materials were methacrylated dextran (DEX-MA) and methacrylated alpha,beta-poly(N-2-hydroxyethyl)-DL-aspartamide (PHM). These polymers were photocrosslinked by exposure of their aqueous solutions at 313 nm without photoinitiators. Different samples, shaped as microparticles, were obtained as a function of polymer concentration and irradiation time. FT-IR analysis confirmed the occurrence of a co-crosslinking between DEX-MA and PHM in all experimental conditions. Size analysis evidenced a narrow particle distribution and swelling studies, performed in twice-distilled water and simulated gastrointestinal fluids, showed a good affinity of these hydrogels towards the aqueous medium. DEX-MA/PHM based hydrogels undergo a negligible chemical hydrolysis, whereas they are partially degraded by dextranase. In vitro biological assays showed cell compatibility of these samples. Beclomethasone dipropionate (BDP), a drug recently proposed for the treatment of 1131) was entrapped into a DEX-MA/PHM based hydrogel and its release was evaluated in the absence or in the presence of dextranase. Obtained release profiles suggest the potential use of BDP loaded DEX-MA/PHM based hydrogels for the treatment of IBD. (c) 2007 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
