STUDY OF TRYPSIN RELEASE IN KINETIC MODELS FROM POLY-N-VINYLPYRROLIDONE BASED pH-SENSITIVE HYDROGEL

In the presented work, the release processes of trypsin immobilized on a pH-sensitive, water-swellable hydrogel sample obtained from the cross-linked of poly-N-vinylpyrrolidone with an average molecular weight of 40 kDa with 10% (mass) N,N'-methylene-bis-acrylamide were studied. The controlled release process was studied in a buffer medium of pH=7, which is close to the small intestine medium. The release of the drug was quantitatively characterized as a function of time. The kinetic data of the release were applied to various kinetic equations such as zero, first order, Higuchi square root law, Korsmeyer-Peppas and Hixon-Crowwell cube root. It was found that the release of trypsin occurs by a non-Fickian diffusion mechanism and the direction of release is well consistent with the Korsmeyer-Peppas release mechanism, so that the poly-N-vinylpyrrolidone-based gel-forming material can be used in the preparation of capsule-type pharmaceutical formulations