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    Examination of drug release from hydrogels
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    Abstract:
    Abstract The liberation of several important active agents was studied from hydrogels produced from new macromolecular substances. Liberation was examined with an in vitro method, with a Hanson's vertical diffusion cell. Polymers were used in an increasing concentration, while the quantity of active agents was constant. Several quantitative relationships were established after the examination of liberation from 240 drug‐containing gels. A power function was found between the concentration of the polymers and the quantity of the liberated active agents, while a logarithmic relationship existed between the viscosity of the gels and the extent of liberation. Interactions between the active agent and the vehicles can be inferred from the rheological functions as well as from the constants of the liberation versus concentration and liberation versus viscosity functions. Copyright © 2003 John Wiley & Sons, Ltd.
    Keywords:
    Liberation
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