the release behavior of tetracycline hydrochloride (tch) from carboxymethyl chitosan (cmcs)/ montmorrilonite (mmt) microcapsules

Abstract microcapsules (mcs) were prepared by the emulsion crosslinking method, where carboxymethyl chitosan (cmcs)/montmorrilonite (mmt) served as the shell materials, and tetracycline hydrochloride (tch) antibiotic as core drug. mcs were characterized by xrd, tga/dtga, and sem. the in vitro drug release behavior of tch from mcs was investigated in different buffer media (ph=4,7 and 9). the release in alkaline medium was higher as compared to acidic and neutral media and mcs displayed a ph-dependent drug release behavior. the drug release kinetic was investigated and a swelling-release model was proposed.