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Updated: Jun 5, 2026
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An Intestine/Liver Microphysiological System for Drug Pharmacokinetic and Toxicological Assessment
Published on: December 3, 2020
Microporous bilayer osmotic tablet for colon-specific delivery.
Anil Chaudhary1, Neha Tiwari, Vikas Jain
1School of Pharmaceutical Sciences, Shobhit University, Meerut, UP, India. anil84_anu@rediff.com
Summary
A novel microporous bilayer osmotic tablet was developed for colon-specific drug delivery, enabling targeted release of dicyclomine hydrochloride and diclofenac potassium without laser drilling. This system offers timed, zero-order drug release for effective Irritable Bowel Syndrome treatment.
Area of Science:
- Pharmaceutical Technology
- Drug Delivery Systems
- Colon Targeting
Background:
- Colon targeting requires specialized drug delivery systems to overcome physiological barriers.
- Osmotic pump tablets offer controlled drug release but often need laser drilling for orifices.
- Biodegradable polymers present an alternative for creating release pores in oral drug delivery.
Purpose of the Study:
- To develop a novel microporous bilayer osmotic pump tablet (OPT) for colon-specific drug delivery.
- To achieve colon targeting of dicyclomine hydrochloride and diclofenac potassium without laser drilling.
- To investigate the influence of formulation variables on drug release kinetics.
Main Methods:
- Fabrication of microporous bilayer osmotic pump tablets using a conventional pan-coating process.
- Coating with a microporous semipermeable membrane and an enteric polymer.
- Utilizing pectin's colon-specific biodegradation to form in situ pores for drug release.
- Evaluating formulation variables including osmogen, HPMC, NaCMC, and pore former content.
Main Results:
- Scanning electron microscopy confirmed the formation of in situ pores post-contact with dissolution medium.
- The number of pores formed was directly related to the amount of pore former in the semipermeable membrane.
- In vitro dissolution studies demonstrated acid resistance and timed, near zero-order drug release up to 24 hours.
Conclusions:
- The developed microporous bilayer osmotic pump tablet effectively targets the colon for drug delivery.
- This novel system avoids the need for laser drilling, simplifying the manufacturing process.
- The optimized tablet formulation shows significant potential for treating Irritable Bowel Syndrome (IBS) through colon-specific drug delivery.
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