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Updated: Jun 7, 2026

Models and Methods to Evaluate Transport of Drug Delivery Systems Across Cellular Barriers
Published on: October 17, 2013
Mathematical modeling of drug delivery from torus-shaped single-layer devices
Ignacio M Helbling1, Julio A Luna, María I Cabrera
1Laboratorio de Química Fina, Instituto de Desarrollo Tecnológico para la Industria Química (INTEC), Universidad Nacional del Litoral and Consejo Nacional de Investigaciones Científicas y Técnicas (UNL-CONICET), CCT CONICET-SANTA FE, Ruta Nacional 168, Paraje El Pozo, 3000, Santa Fe, Argentina. ihelbling@santafe-conicet.gov.ar
Abstract:
A mathematical modeling of controlled release of drug from torus-shaped single-layer devices is presented. Analytical solutions based on the pseudo-steady state approximation are derived. The reliability and usefulness of the model are ascertained by comparison of the simulation results with matrix-type vaginal ring experimental release data reported in the literature. A good agreement between the model prediction and the experimental data is observed. An analysis of the effect of the variation in torus design parameters on the solute release is also presented. The model is applicable only to torus-shaped single-layer systems wherein the initial load of drug is higher than its solubility in the polymer.
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