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Oxycellulose beads with drug exhibiting pH-dependent solubility
Martina Bajerová1, Kateřina Krejčová, Miloslava Rabišková
1Department of Pharmaceutics, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences Brno, Czech Republic. martina.bajerova@seznam.cz
AAPS Pharmscitech
|October 19, 2011
Summary
Novel hydrogel beads made of oxycellulose were developed for targeted drug delivery to the gastrointestinal (GI) tract. These beads effectively encapsulated and released diclofenac sodium over 12-16 hours, showing potential for distal GI drug delivery.
Area of Science:
- Materials Science
- Pharmaceutical Sciences
- Biomedical Engineering
Background:
- Drug delivery systems are crucial for enhancing therapeutic efficacy and patient compliance.
- Targeting specific regions of the gastrointestinal (GI) tract requires sophisticated delivery vehicles.
- Hydrogels offer promising properties for controlled drug release applications.
Purpose of the Study:
- To develop and characterize novel hydrogel-based beads for targeted drug delivery.
- To evaluate the potential of these beads for releasing drugs with pH-dependent solubility in the distal GI tract.
- To investigate the drug-polymer interactions and release kinetics of diclofenac sodium from oxycellulose beads.
Main Methods:
- Oxycellulose beads containing diclofenac sodium were prepared using ionotropic external gelation with calcium chloride.
- Characterization included particle size, sphericity, encapsulation efficiency, swelling studies, and in vitro drug release.
- Fourier transform infrared spectroscopy (FTIR) was used to analyze drug-polymer interactions.
Main Results:
- Particle size ranged from 0.92-1.60 mm, with sphericity between 0.70-0.81.
- Encapsulation efficiency was between 58% and 65%.
- Drug release occurred over 12-16 hours after a 4-hour lag time, with Fickian diffusion as the primary release mechanism.
Conclusions:
- The developed oxycellulose hydrogel beads demonstrate significant potential for targeted drug delivery to the distal GI tract.
- The system is suitable for drugs with pH-dependent solubility, like diclofenac sodium.
- Controlled release profiles and Fickian diffusion suggest effective drug localization and release.
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