International journal of pharmaceutics vol:87 issue:1-3 pages:37-46
In order to develop a colon-specific drug delivery system, copolymers of 2-hydroxyethyl methacrylate and methyl methacrylate were prepared in the presence of bis(methacryloylamino)azobenzene. The conditions of polymerization were optimized to prevent crosslinking. Film coatings were prepared with the azo polymers. The films were insoluble in simulated gastric and intestinal juice. Dependent on the content of the hydrophilic groups in the polymers, the films were more or less permeable to water. In vitro and in vivo tests prove that it is possible to use the polymers to deliver drugs to the large intestine. Due to the presence of the azo compound, the azo polymer coatings can be degraded by intestinal bacteria.