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PubMed · 9552467

Controlled-release tablet matrices from carrageenans: compression and dissolution studies.

M Hariharan·T A Wheatley·J C Price
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Abstract

This study investigates the potential of two commercial carrageenans, Gelcarin GP-379 (iota-carrageenan) and Viscarin GP-209 (lambda-carrageenan) to be used for the preparation of controlled-release tablet matrices. Tablets were compressed on an instrumented Stokes single punch machine and compression characteristics of the carrageenans were analyzed. Heckel plots using out-of-die tablet densities were linear with calculated yield pressures of 81.3 MPa and 105.2 MPa for iota- and lambda-carrageenan, respectively. Drug release from tablet formulations that contained equal amounts of the two carrageenans had near zero-order release profiles. There was little or no effect of tablet compression pressure on the drug release profiles from 70 to 175 MPa. As drug loading was increased from 5 to 20%, the diffusional exponent decreased from 1.056 to 0.678. Thirty percent drug loading resulted in breakup of tablets during dissolution and departure from zero-order release. Multiple regression analysis was used to predict the time for 50% release as a function of the concentration of the two carrageenans and a third filler material, microcrystalline cellulose. Predicted values were in good agreement with observed values and R2 for the final cubic model was 0.9984.

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CarrageenanCompressive StrengthDelayed-Action PreparationsExcipientsLinear ModelsSolubilityTabletsWaterJournal ArticleResearch Support, Non-U.S. Gov't

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M Hariharan, T A Wheatley, J C Price. 1997. Controlled-release tablet matrices from carrageenans: compression and dissolution studies.. https://doi.org/10.3109/10837459709022637

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