Design and development of an innovative water insoluble film-coating combination for oral pulsatile drug delivery

Abstract

There are many situations where a drug needs to be released in a pulsatile manner at a specific time and site in the GI tract. This study presents a novel film-coating, based on a hydrophobic rigid film forming polymer (FFP) imbedded by water insoluble hydrophilic particulates, especially designed for providing a pulsatile drug delivery. Ethyl celluse and calcium pectinate particulates were used as the FFP and hydrophilic component respectively. A fast disintegrating core containing sodium diclofenac as a model drug was used to assess the properties of such a coating combination using a dissolution method. The film-coating showed the capability to breach after a lag time, immediately providing a fast release of the drug during the disintegration of the core. The lag time can be controlled by either the coating weight or the ratio between the components in the coating. The release was found to be insusceptible to pH, pectinolytic enzymes, the agitation rate and to the viscosity of the dissolution medium. The molecular weight of the FFP presented a primary impact on the performance of the film. The findings from this study indicate the ability of such a film-coating combination to create an oral pulsatile drug delivery system.