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10:54
Extraction of Plant-based Capsules for Microencapsulation Applications
Published on: November 9, 2016
Formulation development and in vitro evaluation of theophylline microcapsules
Mahmood Ahmad1, Naveed Akhtar, Ghulam Murtaza
1Faculty of Pharmacy and Alternative Medicines, The Islamia University of Bahawalpur, Bahawalpur, Pakistan. ma786_786@yahoo.com
Pakistan Journal of Pharmaceutical Sciences
|December 22, 2011
Summary
Microencapsulation of theophylline using Eudragit S 100 enhanced sustained release. The optimized formulation (F2) demonstrated comparable release profiles to a commercial product, indicating successful drug delivery system development.
Area of Science:
- Pharmaceutical Technology
- Drug Delivery Systems
- Materials Science
Background:
- Theophylline is a bronchodilator requiring controlled release for effective therapy.
- Microencapsulation offers a viable strategy for modulating drug release kinetics.
- Eudragit S 100 is a pH-sensitive polymer suitable for enteric coating and controlled release applications.
Purpose of the Study:
- To investigate the microencapsulation of theophylline using Eudragit S 100.
- To evaluate the impact of Eudragit S 100 ratios on theophylline release.
- To characterize the release kinetics and stability of theophylline microcapsules.
Main Methods:
- Emulsion solvent evaporation technique for microencapsulation.
- Preparation of theophylline microcapsules with varying Eudragit S 100 concentrations.
- In vitro dissolution studies across different pH conditions and stirring speeds.
- Kinetic modeling (Zero order, First order, Higuchi, Hixson Crowell, Korsmeyer Peppas) to analyze release data.
Main Results:
- Increased Eudragit S 100 content reduced the theophylline release rate.
- Drug release predominantly followed Higuchi's kinetic model.
- Lower release rates were observed at acidic pH (pH 1.0).
- Stirring speed and storage temperature had minimal impact on release profiles.
- Formulation F2 exhibited a sustainable release rate comparable to the commercial product Quibron-T/SR.
Conclusions:
- Eudragit S 100 microencapsulation effectively controls theophylline release.
- The Higuchi model best describes the drug release mechanism.
- Optimized formulation F2 shows potential as a sustained-release theophylline tablet.
- The developed microcapsules offer a promising alternative to existing theophylline formulations.
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