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Development and evaluation of a monolithic floating drug delivery system for acyclovir
Naser Tavakoli1, Jaleh Varshosaz, Farid Dorkoosh
1Department of Pharmaceutics, School of Pharmacy and Isfahan Pharmaceutical Sciences Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
Chemical & Pharmaceutical Bulletin
|February 2, 2012
Summary
This study developed floating drug delivery systems (FDDS) for acyclovir (ACV) to improve oral absorption. Optimized ACV tablets demonstrated excellent in vitro floating and drug release properties, suggesting enhanced bioavailability.
Area of Science:
- Pharmaceutical Sciences
- Drug Delivery Systems
- Antiviral Therapeutics
Background:
- Acyclovir (ACV) is effective against herpes viruses but has variable oral absorption (15-30% bioavailability).
- ACV absorption occurs in the duodenum, making it a candidate for gastroretentive systems like floating drug delivery systems (FDDS).
Purpose of the Study:
- To formulate and evaluate acyclovir (ACV) matrix tablets as a floating drug delivery system (FDDS).
- To enhance the oral absorption and bioavailability of acyclovir through gastroretention.
Main Methods:
- ACV matrix tablets (200 mg) were prepared using direct compression with effervescent bases and polymers (HPMC, carbopol, Na CMC, PVP, sodium alginate).
- Tablets were evaluated for physicochemical properties, in vitro floating ability (lag time, duration), bioadhesiveness, and drug release in 0.1 N HCl.
- Drug release was monitored spectrophotometrically at 259 nm.
Main Results:
- Tablets with 15% effervescent base exhibited a short floating lag time (10-30 s) and long floating duration (24 h).
- Formulations containing HPMC combined with PVP, Na CMC, carbopol, or sodium alginate released 60-90% of ACV over 12 hours.
- Increased carbopol concentration resulted in slower drug release.
Conclusions:
- Optimized ACV tablets containing 15% effervescent base and specific polymer combinations (HPMC-Na CMC, HPMC-PVP, HPMC-carbopol, HPMC-sodium alginate) demonstrated favorable in vitro floating and drug release profiles.
- These FDDS hold promise for improving acyclovir's oral bioavailability and therapeutic efficacy.
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