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Published on: December 23, 2013
Microencapsulated Eudragit RS30D-coated controlled-release pellets: the influence of dissolution variables and
T Govender1, C M Dangor, D J Chetty
1Pharmacy Department, University of Durban-Westville, South Africa.
Journal of Microencapsulation
|January 1, 1997
Summary
Controlled-release salbutamol pellets prepared via air suspension maintain their 8-hour drug release profile across various dissolution methods and pH conditions. Dissolution testing confirmed consistent performance, independent of method but influenced by pH.
Area of Science:
- Pharmaceutical Technology
- Drug Delivery Systems
Background:
- Controlled-release formulations aim to optimize drug delivery and patient compliance.
- Eudragit RS30D is a common polymer for creating pH-independent or pH-dependent drug release profiles.
- Salbutamol is a widely used bronchodilator for managing asthma and COPD.
Purpose of the Study:
- To investigate the influence of dissolution methods and pH on salbutamol release from Eudragit RS30D-coated pellets.
- To confirm the controlled-release characteristics of the prepared pellets under simulated gastrointestinal conditions.
Main Methods:
- Air suspension technique for pellet preparation.
- In vitro dissolution testing using USP XXII rotating basket, rotating paddle, and rotating bottle methods.
- Evaluation of drug release at different pH values (1.5, 6.8, 7.2) and a simulated gastrointestinal pH gradient.
- Scanning electron microscopy (SEM) for physical characterization.
Main Results:
- Drug release was independent of the dissolution method employed (rotating basket, paddle, bottle).
- Pellets exhibited pH-dependent drug release, with consistent 8-hour release observed.
- Simulated gastrointestinal conditions confirmed sustained drug release over 8 hours.
- SEM provided insights into pellet morphology and drug release mechanisms.
Conclusions:
- The air suspension method effectively produced controlled-release salbutamol pellets.
- The pellets demonstrate robust performance across various dissolution methods and pH conditions, maintaining sustained release.
- These findings support the potential of these pellets for effective oral drug delivery of salbutamol.
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