Determination of Intraparticulate Mass Transfer Coefficients via Permeation Measurements: Theory and Experimental Validation
| Autor: | Edward G. Rippie, Wei-Cheng Liaw |
|---|---|
| Rok vydání: | 1996 |
| Předmět: |
Mass transfer coefficient
Molecular diffusion Antimetabolites Differential equation Chemistry Water Pharmaceutical Science Thermodynamics Membranes Artificial General Medicine Penetration (firestop) Experimental validation Permeation Diffusion Linear relationship Models Chemical Mass transfer Emulsions Fluorouracil Oils |
| Zdroj: | Pharmaceutical Development and Technology. 1:77-89 |
| ISSN: | 1097-9867 1083-7450 |
| DOI: | 10.3109/10837459609031421 |
| Popis: | A mathematical model of mass transfer through a heterogeneous, multiphase barrier has been developed where the dispersed phase is capable of uptake of the diffusant according to a linear relationship. The model was used to describe the penetration of drugs through dispersions of permeable globules in media of known diffusional properties. Water-in-oil-in-water (W/O/W) multiple emulsions have been studied by this method. When used to analyze data obtained with a simple diffusion cell, the model allows the calculation of the mass transfer coefficient which characterizes the diffusional mass transfer across oil-water interfaces within the emulsions. The mass transfer coefficient is directly related to the drug release rate from the internal phases of multiple emulsions. Those cases where instantaneous equilibria are established or where impermeable globules are present can be treated as special limiting cases. Differential equations which express diffusant concentrations as functions of time, space, and dispersion system parameters have been solved by Laplace transformation without recourse to numerical methods. The values of the mass transfer coefficient are shown to reflect the physical characteristics of multiple emulsion systems. |
| Databáze: | OpenAIRE |
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