Sulpiride gastro-retentive floating microsponges; analytical study, in vitro optimization and in vivo characterization

Abstract

Sulpiride (SUL), anti-dopaminergic drug, has a specific site for absorption located in the upper portion of the gastrointestinal tract hence, its oral delivery represents a challenge regarding SUL absorption and bioavailability. So, a gastro-retentive oral platform of SUL was developed to increase its gastric residence time, release SUL at a controlled rate in the stomach and consequently, enable it to reach its specific absorption site. Floating microsponges were prepared via quasi-emulsion solvent diffusion method and characterised for their physico-chemical properties. In addition, Taguchi design of experiment was utilised to optimise some independent variables affecting microsponges performance. The optimised SUL microsponges showed a yield of 79.82 ± 2.37%, an encapsulation efficiency of 89.11 ± 2.28% and in vitro time for floatation of 8.0 h. Additionally, pharmacokinetics were investigated in rabbits and compared with the commercial SUL formulation, Dogmatil^® capsules. Optimised SUL microsponges showed a significantly (p < .05) higher C_max, AUC and 2-fold increase in oral bioavailability compared with the commercial product. Moreover, the optimised SUL microsponges remained present in the stomach up to 8.0 h post administration when viewed via X-ray radiographs in rabbits. It could be concluded that the floating microsponges could be useful as an oral platform to enhance the sulpiride absorption and bioavailability.

Keywords:

• Sulpiride
• gastroretension
• Taguchi design of experiment
• oral bioavailability
• charge-transfer complexation reaction

Acknowledgements

The authors are thankful to Faculty of Pharmacy, Assiut University, Egypt for funding and facilitating this study. The authors are also thankful to Assiut University Veterinary Hospital for facilitating X-ray imaging of animals.

Disclosure statement

The authors report no conflict of interests regarding this work.