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Updated: Jul 18, 2026
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Quantifying Mixing using Magnetic Resonance Imaging
Published on: January 25, 2012
A study of tablet dissolution by magnetic resonance electric current density imaging
Ursa Mikac1, Alojz Demsar, Franci Demsar
1Jozef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia. urska.mikac@ijs.si
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|December 26, 2006
Summary
Electric current density imaging (CDI) monitored tablet dissolution by tracking conductivity changes. This technique accurately measured ion concentration changes, demonstrating CDI
Area of Science:
- Electrochemistry
- Materials Science
- Chemical Engineering
Background:
- Monitoring the dissolution of ion-releasing materials is crucial for various applications.
- Traditional methods for tracking ion release can be complex and invasive.
- Developing non-invasive techniques for real-time monitoring of ion migration is needed.
Purpose of the Study:
- To evaluate the electric current density imaging (CDI) technique for monitoring ion-releasing tablet dissolution.
- To quantitatively assess spatial and temporal changes in ionic concentrations around dissolving tablets.
- To determine diffusion constants of various acids using experimental data and mathematical modeling.
Main Methods:
- Utilized electric current density imaging (CDI) to observe conductivity changes in an agar-agar gel surrounding dissolving tablets.
- Calculated spatial and temporal changes in ionic concentrations based on measured conductivity variations.
- Compared experimental ion migration data with a mathematical diffusion model featuring moving boundary conditions.
Main Results:
- CDI successfully monitored the dissolution process of ion-releasing tablets (carboxylic acids, NaCl).
- The technique allowed for the calculation of ionic concentration changes in the surrounding medium.
- Diffusion constants for different acids were determined by fitting the mathematical model to experimental CDI data.
Conclusions:
- Electric current density imaging (CDI) is a viable technique for monitoring ion release from dissolving samples.
- CDI provides valuable data on spatial and temporal ion concentration changes.
- The study demonstrates the potential of CDI for in-situ measurements in proximity to ion-releasing materials.
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