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arXiv · 2004.05921

Modelling drug delivery from multiple emulsions

G. Pontrelli·E. J. Carr·A. Tiribocchi·S. Succi
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Abstract

We present a mechanistic model of drug release from a multiple emulsion into an external surrounding fluid. We consider a single multi-layer droplet where the drug kinetics are described by a pure diffusive process through different liquid shells. The multi-layer problem is described by a system of diffusion equations coupled via interlayer conditions imposing continuity of drug concentration and flux. Mass resistance is imposed at the outer boundary through the application of a surfactant at the external surface of the droplet. The two-dimensional problem is solved numerically by finite volume discretization. Concentration profiles and drug release curves are presented for three typical round-shaped (circle, ellipse and bullet) droplets and the dependency of the solution on the mass transfer coefficient at the surface analyzed. The main result shows a reduced release time for an increased elongation of the droplets.

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G. Pontrelli, E. J. Carr, A. Tiribocchi, S. Succi. 2020-04-09. Modelling drug delivery from multiple emulsions. https://doi.org/10.1103/physreve.102.023114

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