Acta Pharm. 57 (2007) 301-314
10.2478/v10007-007-0024-6

 

full paper

Original research paper

 

Swelling behavior and release properties of pH-sensitive hydrogels based on methacrylic derivatives

 

TAHAR BARTIL*1, MAHMOUD BOUNEKHEL1, CALBERG CEDRIC2 and ROBERT JEROME2

tbartil2002@yahoo.fr

1Département de génie des procédés Faculté des sciences de l’ingénieur, Université ferhat Abbas SETIF (19000), Algérie

2Centre de recherche et d’étude sur les macromolécules (CERM) B6 chimie, Université de Liège Sart-Tilman, 4000-Liege, Belgique aculty of Pharmacy and Biochemistry, University of Zagreb, 10000 Zagreb, Croatia

Accepted July 9, 2007

 

The purpose of this study is to develop novel intestinal-specific drug delivery systems with pH sensitive swelling and drug release properties. Methacrylic-type polymeric prodrugs were synthesized by free radical copolymerization of methacrylic acid, poly(ethyleneglycol monomethyl ether methacrylate) and a methacrylic derivative of N-(4-hydroxyphenyl)-2-(4-methoxyphenyl) acetamide in the presence of ethylene glycol dimethacrylate as crosslinking agent. The effect of copolymer composition on the swelling behavior and hydrolytic degradation were studied in simulated gastric (SGF, pH 1.2) and intestinal fluids (SIF, pH 7.0). The dynamic swelling behavior of these hydrogels was investigated to determine the mechanism of water transport through these hydrogels. The mechanism of water transport through the gels was significantly affected by the pH of the swelling medium and became more relaxation-controlled in a swelling medium of pH 7.0. The swelling and hydrolytic behaviors of hydrogels were dependent on the content of methacrylic acid (MAA) groups and caused a decrease and increase in gel swelling in SGF and SIF, respectively. Drug release studies showed that the increasing content of MAA acid in the copolymer enhances hydrolysis in SIF. These results suggest that pH-sensitive systems could be useful for preparation of a muccoadhesive system and controlled release of N-(4-hydroxyphenyl)-2-(4-methoxyphenyl) acetamide.

 

Keywords: pH-sensitive hydrogels, swelling, controlled release, poly(ethylene glycol), poly(methacrylic acid)

 

 

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*Correspondence ; e-mail

 
 

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