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Coherent anti-Stokes Raman Scattering (CARS) Microscopy Visualizes Pharmaceutical Tablets During Dissolution
Published on: July 4, 2014
Hydrodynamic simulation (computational fluid dynamics) of asymmetrically positioned tablets in the paddle dissolution
D M D'Arcy1, O I Corrigan, A M Healy
1School of Pharmacy, University of Dublin, Trinity College, Dublin 2, Ireland.
The Journal of Pharmacy and Pharmacology
|November 2, 2005
Summary
Dissolution rates of benzoic acid compacts increase with off-center placement in dissolution vessels. Fixing compacts reduces result variability, while computational fluid dynamics (CFD) models fluid flow and dissolution dynamics.
Area of Science:
- Pharmaceutical Sciences
- Chemical Engineering
- Physical Chemistry
Background:
- Understanding drug dissolution is crucial for predicting in vivo performance.
- Compact positioning in dissolution apparatus can significantly influence results.
- Variability in dissolution testing necessitates investigation into influencing factors.
Purpose of the Study:
- To investigate benzoic acid dissolution rates from different surfaces and positions.
- To assess the impact of compact fixation on dissolution variability.
- To correlate local hydrodynamics with dissolution rates using CFD.
Main Methods:
- Dissolution testing of cylindrical benzoic acid compacts in a paddle apparatus.
- Varying compact placement (central vs. non-central) and fixation.
- Computational Fluid Dynamics (CFD) simulations of fluid flow around compacts.
- Analysis of dissolution rate and surface morphology changes.
Main Results:
- Dissolution rate increased from central to off-center positions for both planar and curved surfaces.
- Fixing compacts reduced variability in dissolution results compared to unfixed ones.
- CFD simulations showed increased fluid velocities at off-center positions, correlating with higher dissolution rates.
- Asymmetric fluid flow led to observable changes in compact erosion patterns.
Conclusions:
- Compact positioning significantly impacts benzoic acid dissolution rates and variability.
- CFD is a valuable tool for modeling hydrodynamics and understanding dissolution behavior.
- Optimizing compact placement and fixation can improve dissolution test reproducibility.
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