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Updated: Mar 16, 2026
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An Intestine/Liver Microphysiological System for Drug Pharmacokinetic and Toxicological Assessment
Published on: December 3, 2020
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Dissolution profile of theophylline modified release tablets, using a biorelevant Dynamic Colon Model (DCM)
Konstantinos Stamatopoulos1, Hannah K Batchelor2, Mark J H Simmons1
1School of Chemical Engineering, University of Birmingham, Birmingham B15 2TT, United Kingdom.
Summary
A new Dynamic Colon Model (DCM) simulates the human colon's complex environment for drug delivery. This advanced in vitro model accurately predicts how drug dosage forms will perform in the body.
Area of Science:
- Pharmacology
- Gastroenterology
- Biomedical Engineering
Background:
- The proximal colon is a key site for drug delivery, but its dynamic environment challenges dosage form performance.
- Existing in vitro models often fail to replicate the colon's complex hydrodynamics and physiological conditions.
- Accurate prediction of in vivo drug performance requires models that incorporate colonic biomechanics.
Purpose of the Study:
- To develop and validate a novel biorelevant Dynamic Colon Model (DCM) that mimics the proximal human colon.
- To assess the influence of colonic hydrodynamics and physiological parameters on drug dissolution and distribution.
- To improve the in vitro prediction of drug dosage form performance in the human colon.
Main Methods:
- Development of a Dynamic Colon Model (DCM) simulating colonic smooth muscle architecture, pressure, and motility.
- Measurement of pressure dynamics within the DCM in relation to fluid viscosity and membrane occlusion.
- Assessment of theophylline dissolution and distribution using Positron Emission Tomography (PET) imaging and sampling at various locations.
Main Results:
- DCM pressure measurements correlated with fluid viscosity and occlusion rate, validating its physiological relevance.
- Drug release rates varied significantly based on sampling location, fluid viscosity, and mixing dynamics within the DCM.
- PET imaging revealed convective fluid motion, linking tracer distribution to potential drug concentration hotspots and precipitation zones.
Conclusions:
- The Dynamic Colon Model (DCM) offers a realistic in vitro platform for studying drug delivery in the proximal colon.
- Understanding hydrodynamics and physiological factors is crucial for predicting drug behavior, including supersaturation and precipitation.
- This model enhances the ability to predict in vivo drug performance, optimizing dosage form design for colonic delivery.
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