Peceosomes for oral delivery of glibenclamide: In vitro in situ correlation

Peceol containing niosomes (peceosomes) have been shown to widen absorption window of acidic drugs. However, the relationship between drug release and intestinal absorption is not clear. Accordingly, the objective was to probe peceosomes for enhancing intestinal absorption of glibenclamide with the goal of correlating drug release with intestinal absorption. Glibenclamide was encapsulated into peceosomes. The drug entrapment and release were determined at pH values of 6.6 and 7.4. In situ rabbit intestinal absorption of glibenclamide was monitored from peceosomes with reference to aqueous solution. The entrapment efficiency of glibenclamide was 89.3% and 68.7% with the release efficiency being 6.5% and 19.1% at pH 6.6 and 7.4, respectively. In situ perfusion of glibenclamide solution reflected incomplete absorption from duodenum and jejuno-ileum. Peceosomal encapsulation enhanced glibenclamide intestinal absorption with complete absorption being achieved from jejuno-ileum. Correlating intestinal absorption with in vitro release, the former was always greater. This indicates that drug release rate is not the rate limiting step. Taking this into consideration together with augmented jejuno-ileal transcellular absorption, intact peceosomal translymphatic absorption can be suggested. The study confirmed the ability of peceosomes to widen absorption window of acidic drugs and highlighted the need for drug retention in vesicles for efficient delivery.

244