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Preparation of Controlled-Release Fine Particles Using a Dry Coating Method.
Shohei Nakamura1, Takatoshi Sakamoto2, Tomonori Ito2
1Department of Pharmaceutical Technology, College of Pharmaceutical Sciences, Matsuyama University, 4-2 Bunkyo-cho, Matsuyama, Ehime, 790-8578, Japan. snakamur@cc.matsuyama-u.ac.jp.
AAPS Pharmscitech
|January 16, 2016
Summary
A novel dry coating method creates fine, multi-layered particles for controlled-release theophylline. This technique avoids issues associated with wet coating, offering improved pharmaceutical stability and drug delivery.
Area of Science:
- Pharmaceutical Technology
- Materials Science
- Drug Delivery Systems
Background:
- Wet coating methods for controlled-release medications often lead to particle agglomeration, reduced drug stability, and residual organic solvents.
- Developing advanced drug delivery systems requires overcoming the limitations of traditional coating techniques.
Purpose of the Study:
- To develop and evaluate a dry coating method for producing multi-layered, controlled-release drug particles.
- To overcome the disadvantages of wet coating, such as agglomeration and residual solvents.
Main Methods:
- Utilized a dry coating technique involving an ultrahigh-speed mixer to coat cornstarch (CS) particles with theophylline (TP) as the model drug.
- Incorporated polyethylene glycol 20,000 (PEG) as a drug fixative, and hydrogenated castor oil (HCO) and hydrogenated rapeseed oil (HRSO) as controlled-release materials.
- Achieved particle sizes below 50 μm with a drug reservoir and a controlled-release layer.
Main Results:
- The dry coating method successfully produced multi-layer coated single-core particles less than 50 μm in diameter.
- Theophylline (TP) dissolution was less than 10% after 8 hours, indicating effective controlled release.
- Demonstrated the feasibility of coating 16-μm CS particles with both a drug reservoir and a controlled-release layer.
Conclusions:
- The developed dry coating method offers a viable alternative to wet coating for preparing controlled-release drug particles.
- This technique effectively minimizes particle agglomeration and enhances pharmaceutical stability.
- The resulting multi-layered particles are suitable for various dosage forms, including tablets, capsules, and orally disintegrating tablets.
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