204
Views
9
CrossRef citations to date
0
Altmetric
Original Article

Preparation and evaluation of a novel gastric mucoadhesive sustained-release acyclovir microsphere

, , , &
Pages 1098-1105 | Received 04 Dec 2009, Accepted 03 Feb 2010, Published online: 05 Nov 2010
 

Abstract

Objective: The objective of this study was to prepare a novel gastric mucoadhesive sustained-release acyclovir (AV)-resinate microsphere. Methods: First, AV absorption ratio was quantified in a rat gastrointestinal (GI) tract model. AV-resinate was prepared by bath method and used as cores to prepare microspheres by an emulsion solvent diffusion technique with carbopol 934 as coating material. GI transit test of the prepared microspheres was carried out in rats and beagle dogs, followed by the in vivo bioavailability evaluation of the microspheres in beagle dogs. Results: The AV absorption ratio in different segments of rat's GI track for 3 hours was as following: stomach 9.46 ± 0.62%, duodenum 20.22 ± 1.50%, jejunum 15.7 ± 1.33%, ileum 9.15 ± 1.01%, and colon 4.59 ± 0.48%. These results showed that AV was mainly absorbed in the stomach and upper intestine. The average diameter of the microspheres was 115.3 μm. The microspheres had a drug content of 33.3 ± 0.7% (w/w) and a sustained-release profile for 12 hours in vitro. The mucoadhesive test in rats and beagle dogs showed that most of the microspheres were retained in the stomach 6 hours after oral administration. The in vivo pharmacokinetics test revealed that the microsphere and reference (AV tablets) preparations have no significant difference for Cmax. The tmax has increased from 2.33 hours (reference) to 5 hours (test). Meanwhile, the relative bioavailability of AV microspheres was 145%. Conclusion: A novel AV-resinate microsphere was prepared. The microspheres were proved to be gastric mucoadhesive and sustained-release with higher bioavailability.

View correction statement:
Erratum

Acknowledgments

Thanks to Professor Molly Stevens (Imperial College London) for his support.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this paper.

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.