Oily in situ gels as an alternative floating platform for ketoconazole release

Sodium alginate, calcium carbonate, and guar gum were mixed with oils such as olive oil (OO), sesame oil (SO), and medium chain triglyceride (MCT). The oily formulations were found to simplify the preparation of in situ floating gel. This was the aim of this study using ketoconazole (keto) as a model drug. The investigations for the floating property were established by In vitro gelling capacity study and In vitro floating study. Additionally, in vitro release study was applied to find the best formulations to delay the release of keto. Then, selected formulations were studied by FTIR and SEM. Lastly, in vivo gelation was performed to examine the gelation in the rat’s stomach. The results showed all formulations were floating after successful gelation as the least amount of sodium alginate to gel oils was 20% w/w. The gels in SO and OO were better than MCT in delaying keto release, and 30% w/w sodium alginate in SO was the best to delay the release of keto within 8 hours of the release study. Selected gels showed interactions between the keto molecules and the molecules of the gel contents by FTIR study, and SEM showed a difference in the internal structure of selected formulations. Lastly, the 30% w/w sodium alginate in SO proved to gel and remain in the rat's stomach in the following periods: 30 min, 1 hour, 2 hours, and after 8 hours. Oily suspension formulations showed floating properties in the stomach and slowed the release of keto and specifically 30% w/w of sodium alginate in SO.