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Floating microspheres of valacyclovir HCl: Formulation, optimization, characterization, in vitro and in vivo
Nilamgiri Goswami1, Garima Joshi, Krutika Sawant
1TIFAC Centre of Relevance and Excellence, M S University of Baroda, Vadodara, Gujarat.
Journal of Pharmacy & Bioallied Sciences
|October 16, 2012
Summary
Floating microspheres were developed for Valacyclovir hydrochloride (VCH) to improve drug absorption by localizing it in the upper gastrointestinal tract. These gastroretentive systems demonstrated effective floating behavior, offering a promising alternative to standard drug formulations.
Area of Science:
- Pharmaceutical Sciences
- Drug Delivery Systems
Background:
- Valacyclovir hydrochloride (VCH) is a prodrug of acyclovir susceptible to degradation in the intestinal environment.
- Gastroretentive drug delivery systems aim to prolong drug residence time in the upper gastrointestinal tract (GIT) for enhanced absorption.
Purpose of the Study:
- To develop and characterize floating microspheres of Valacyclovir hydrochloride (VCH).
- To achieve gastric retention of VCH for improved therapeutic efficacy.
Main Methods:
- Floating microspheres were prepared using the W/O emulsification solvent evaporation technique.
- Ethylcellulose (EC) was employed as the primary polymer for microsphere formulation.
- Particle size, entrapment efficiency, and in vitro/in vivo floatability were evaluated.
Main Results:
- Microspheres exhibited a particle size of 550.021±0.241 μm.
- The entrapment efficiency (% EE) for VCH was determined to be 79.88±2.236%.
- Successful in vitro and in vivo floatability studies confirmed the gastroretentive potential of the microspheres.
Conclusions:
- Developed VCH-loaded floating microspheres demonstrate effective gastroretentive properties.
- These microspheres offer a viable alternative to conventional formulations for enhancing VCH absorption in the upper GIT.
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