Gastro retention using polymer cocoons

Abstract

A gastro-retentive capsule has been prepared which is retained in the stomach for a period of 24h, providing a vehicle for the controlled delivery to the upper intestines. These “gastro cocoons” can resist passage through the sphincter of the stomach, and can retain a high drug payload (30%). They are made from oppositely charged polyelectrolytes and can swell to twice their initial volume. They are strong and also can resist 550 N of compressive force. They are based on filled pharmaceutical capsules which are visible to X-rays. Using ambroxol hydrochloride as a model drug linear, zero-order, release curves were obtained.

Keywords::

• drug-delivery
• encapsulation
• gastro-retention
• polyelectrolyte

Acknowledgments

The authors would like to thank Klaus Eichler, for his work on the project since the outset as well as Diogo Figueiredo for his assistance in the library as well as with graphics. We would also like to thank Dr. Redouan Mahou of the EPFL (Lausanne) for providing access to the mechanical testing equipment, Peter Langguth, Pharmaceutical Technology & Biopharmaceutics Institut, Johannes Gutenberg-University Mainz, Germany, for his work on the swelling of the capsules, and Prof. Gra a Rasteiro and Ms. Maria Jo o Travassos, both of the Department of Chemical Engineering, University of Coimbra, for the light scattering measurements.

Control-release experiments were carried out at the University of Basel's Pharma Centrum courtesy of Dr. Maxim Puchkov. X-ray testing as well as the canine studies were graciously carried out my Prof. Farzaneh Sharifi Aghdas and her team at the Shahid Beheshti University of Medical Sciences (Tehran). The animal experiments were carried out by Mohammad Naji of the Urology and Nephrology Research Center (UNRC), Shahid Beheshti University of Medical Sciences, Tehran, Iran. The animal facility was located at the Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.

Declaration of interest

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