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A Method for Determination and Simulation of Permeability and Diffusion in a 3D Tissue Model in a Membrane Insert System for Multi-well Plates
Published on: February 23, 2018
Percolative drug diffusion from cylindrical matrix systems with unsealed boundaries
U Brohede1, S Valizadeh, M Strømme
1Department of Engineering Sciences, The Angström Laboratory, Uppsala University, PO Box 534, SE-751 21 Uppsala, Sweden.
Journal of Pharmaceutical Sciences
|August 28, 2007
Summary
Drug release from ethyl cellulose tablets occurs via two overlapping processes, influenced by pore structure and porosity. This research informs the design of advanced controlled drug delivery systems.
Area of Science:
- Pharmaceutical Sciences
- Materials Science
- Chemical Engineering
Background:
- Controlled drug delivery aims to optimize therapeutic efficacy and patient compliance.
- Understanding drug release mechanisms from matrix tablets is crucial for formulation design.
- Previous studies often focused on unidirectional drug release, limiting applicability.
Purpose of the Study:
- To investigate NaCl release in multiple directions from cylindrical ethyl cellulose tablets.
- To characterize the pore structure and its influence on drug release kinetics.
- To provide insights for developing tailored drug delivery vehicles with specific release profiles.
Main Methods:
- Alternating ionic current method for monitoring NaCl release.
- Mercury porosimetry and scanning electron microscopy for pore structure analysis.
- Krypton gas adsorption for determining fractal surface dimension.
Main Results:
- Drug release comprises two overlapping processes: boundary dissolution/diffusion and bulk diffusion.
- A porosity percolation threshold of 0.22 was identified.
- Effective-medium behavior was observed at a porosity of approximately 0.44.
- Release from unsealed walls differs significantly from unidirectional release models.
Conclusions:
- The pore structure and multi-directional release significantly impact drug release kinetics.
- Findings highlight the importance of considering tablet geometry and porosity in drug delivery design.
- This study offers valuable knowledge for optimizing controlled drug release formulations.
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