PREPARATION OF A NOVEL TYPE OF CONTROLLED-RELEASE CARRIER AND EVALUATION OF DRUG RELEASE FROM THE MATRIX TABLET AND ITS PHYSICAL-PROPERTIES

Solved mixtures of hydrogels (SMH), composed of hydroxypropylcellulose (HPC), a pseudo-hydrogel, and ethylcellulose, a water-insoluble polymer, were prepared by solvent evaporation. Phenylpropanolamine hydrochloride was used as a model drug. The amount of drug released from a matrix tablet containing SMH powder and the drug increased with decreasing weight fraction of HPC (WFH) in SMH. SMH showed improved properties compared to HPC alone, for example, flowability and hydroscopicity. These properties increased with decreasing WFH. The sorption apparatus described in this study is capable of an immediate, sensitive and accurate response to initial moisture sorption. The kinetics of moisture sorption measurement using this apparatus is useful for a preliminary study.