Drug release profile of acetaminophen APAP in cellulose exci

Drug release profile of acetaminophen (APAP) in cellulose excipient was
observed by dissolving the tablet in the saturated solution of APAP. If the
initial porosity of the tablet before dissolution is 2%, diffusion constants of
excipient and APAP are 0.3 and 0.5,

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Solution

INTRODUCTION:
Ethylcellulose polymer is widely used in pharmaceutical coating, especially when producing modified release
dosage forms. Drug release through barrier membrane systems is influenced by several process and
formulation variables; however, our understanding of the influence of these variables is hindered by a lack of
comprehensive models to guide our coating efforts. The purpose of this work was to study the influence of an
aqueous or an organic coating process on drug release profile characteristics from an ethylcellulose barrier
membrane coated multiparticulate system.
Either ETHOCEL ethylcellulose (Standard 20 Premium, The Dow Chemical Company) or aqueous
ethylcellulose dispersion (Surelease E-7-19040, Colorcon, USA) was used as the barrier membrane polymer.
Hypromellose (HPMC, METHOCEL