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Published on: October 29, 2013
Influence of ethanol on aspirin release from hypromellose matrices
Matthew Roberts1, Marco Cespi, James L Ford
1School of Pharmacy and Chemistry, Liverpool John Moores University, Byrom St. L3 3AF, UK. M.Roberts1@ljmu.ac.uk
Abstract:
Release profiles of aspirin from hypromellose matrices in hydro-ethanolic media were studied. Percent aspirin released increased with increasing levels of ethanol in the dissolution media, correlating with the drug's solubility, however, dose dumping of aspirin did not occur. An initial rapid release was observed in media comprising 40% ethanol. Release in these conditions was considered to be both erosion and diffusion-mediated, in contrast to the release in 0, 10, 20 and 30% ethanol media, where erosion-controlled release dominated. Image analysis of matrix swelling indicated a slower initial interaction between ethanol and hypromellose accounting for the initial rapid release. Cloud point studies suggested that ethanol retarded hydration of the polymer.
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