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Development of extended release dosage forms using non-uniform drug distribution techniques
Kuo-Kuang Huang1, Da-Peng Wang, Chung-Ling Meng
1Tajen Institute of Technology, Pingtung, Taiwan. leon@ccsun.tajen.edu.tw
Drug Development and Industrial Pharmacy
|July 9, 2002
Summary
This study developed an extended-release nifedipine oral dosage form using a non-uniform drug distribution method. The optimized formulation achieved a zero-order release rate, maintaining constant plasma concentration.
Area of Science:
- Pharmaceutical Sciences
- Drug Delivery Systems
- Materials Science
Background:
- Extended-release formulations aim to improve therapeutic efficacy and patient compliance.
- Achieving zero-order drug release is a key goal for sustained therapeutic effects.
- Non-uniform drug distribution offers a novel approach to control drug release kinetics.
Purpose of the Study:
- To develop an extended-release oral dosage form for nifedipine.
- To optimize the non-uniform drug distribution matrix method for controlled nifedipine release.
- To achieve a zero-order release rate for nifedipine.
Main Methods:
- Utilized a fluid bed processing unit for coating non-pareil beads with nifedipine.
- Controlled nifedipine concentration gradient and spray rate during coating.
- Employed instantaneous dilutions of coating solution with polymer dispersion.
- Evaluated release rate characteristics using USP dissolution method (100 rpm, 0.1 N HCl, 37°C).
Main Results:
- Increased ethyl cellulose content decreased nifedipine release rate.
- Incorporation of sucrose increased nifedipine release rate.
- Adjusted spray coating and polymer dispersion rates achieved zero-order release.
Conclusions:
- The non-uniform drug distribution technique successfully produced an extended-release nifedipine dosage form.
- Zero-order release and constant plasma concentration were achieved.
- Further in vivo/in vitro correlation studies are warranted for this drug delivery system.
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