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PubMed · 977604

A unified mathematical model for diffusion from drug-polymer composite tablets.

J C Fu·C Hagemeir·D L Moyer
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Abstract

The derivation and experimental verification of a unified mathematical model for the estimation of drug release rate from drug-polymer composite tablets are presented. Cylindrical coordinates are utilized in the solution of the diffusion equation for a three-dimensional system. The model is applicable to tablets that range from the shape of a flat disk (radius greater than thickness) to that of a cylindrical rod (radius less than thickness). The general solution for the fraction of drug released at a time t is (see article). This approach to a three-dimensional system, utilizing cylindrical coordinates, presents a comprehensive method for the estimation of drug release rates from sustained release tablets with drug distributed homogeneously throughout a polymer matrix. The calculated and experimental drug diffusion rate of pyrimethamine from pyrimethamine-silicone rubber composite tablets that range in shape from that of a disk to a cylinder, and of hydrocortisone from EVA, polycaprolactone, and PVA terpolymer, are compared.

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CaprolactamDelayed-Action PreparationsDiffusionEthylenesHalf-LifeHydrocortisoneMathematicsModels, TheoreticalPolymersPyrimethamineSiliconesTabletsTime FactorsJournal Article

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BibTeXRIS

J C Fu, C Hagemeir, D L Moyer. 1976. A unified mathematical model for diffusion from drug-polymer composite tablets.. https://doi.org/10.1002/jbm.820100507

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