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Sustained release coating of tablets with Eudragit(®) RS/RL using a novel electrostatic dry powder coating process
Mingxi Qiao1, Yanfeng Luo, Liqiang Zhang
1Department of Chemical and Biochemical Engineering, University of Western Ontario, London, Ontario, Canada.
International Journal of Pharmaceutics
|August 4, 2010
Summary
This study developed an electrostatic dry powder coating for sustained release tablets using Eudragit® RS/RL. The process, involving a plasticizer and electrostatic powder spraying, offers an effective alternative for controlled drug delivery.
Area of Science:
- Pharmaceutical Technology
- Materials Science
- Drug Delivery Systems
Background:
- Conventional tablet coating methods face challenges in achieving uniform and controlled drug release.
- Eudragit® RS/RL polymers are widely used for sustained drug release applications.
- Developing efficient and alternative coating techniques is crucial for pharmaceutical innovation.
Purpose of the Study:
- To develop an electrostatic dry powder coating process for sustained release tablets.
- To investigate the influence of process parameters on coating characteristics and drug release.
- To evaluate Eudragit® RS/RL for electrostatic dry powder coating applications.
Main Methods:
- Development of an electrostatic dry powder coating technique using Eudragit® RS/RL.
- Application of a liquid plasticizer (triethyl citrate) followed by electrostatic powder spraying.
- Curing of coated tablets at elevated temperatures to ensure film formation.
- In vitro drug release studies to assess sustained release profiles.
Main Results:
- Electrostatic charging significantly enhanced coating deposition efficiency.
- Liquid plasticizer improved polymer properties (lower T(g), increased conductivity) for better coating.
- Curing temperature and time were critical for effective film formation.
- Curing time, temperature, coating level, and polymer ratio influenced the sustained release profile.
Conclusions:
- The electrostatic dry powder coating process is a viable alternative for sustained release tablet coating.
- Process parameters like curing conditions and coating level are key to controlling drug release.
- This method offers potential for developing advanced drug delivery systems with Eudragit® polymers.
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