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Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
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Prediction of coning phenomena for irregular particles in paddle dissolution test
Mizuki Higuchi1, Shunki Nishida1, Yasuo Yoshihashi1
1Department of Pharmaceutics, Faculty of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan.
Summary
The Zwietering equation accurately predicts particle behavior in dissolution testing. It successfully forecasts the no coning speed for non-spherical, porous, and swellable particles, aiding dissolution test method development.
Area of Science:
- Pharmaceutical Sciences
- Chemical Engineering
- Materials Science
Background:
- Predicting particle behavior in dissolution testing is crucial for method development.
- Coning phenomena can affect dissolution test results.
- The Zwietering equation is a theoretical model for predicting powder dynamics.
Purpose of the Study:
- To evaluate the Zwietering equation's ability to predict coning phenomena.
- To assess its applicability for non-spherical, porous, and swellable particles.
- To determine its utility in paddle dissolution testing.
Main Methods:
- Utilized the Zwietering equation to model particle behavior.
- Investigated the influence of particle shape (non-spherical) and properties (porous, swellable).
- Determined the minimum rotation speed for coning disappearance (NCrpm).
Main Results:
- Stokes diameter or short side length accurately predicted NCrpm for non-spherical particles.
- Stokes density accurately predicted NCrpm for porous and swellable particles.
- The Zwietering equation demonstrated sufficient accuracy for dissolution test development.
Conclusions:
- The Zwietering equation is applicable for predicting coning phenomena in paddle dissolution tests.
- It provides reliable predictions for diverse particle types, including non-spherical, porous, and swellable ones.
- This validates its use in developing robust dissolution testing methodologies.
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