Nanoemulsions as novel oral carriers of stiripentol: insights into the protective effect and absorption enhancement

Abstract

Oral administration remains a significant challenge in regards to drugs with serious solubility and stability issues. This article aimed to investigate the suitability of nanoemulsions as oral carriers of stiripentol (STP), an acid-labile drug, for enhancement of stability and bioavailability. STP-loaded nanoemulsions (STP-NEs) were prepared by using a solvent-diffusion/ultrasonication technique. STP-NEs were characterized in a variety of ways such as by particle size, entrapment efficiency, in vitro drug release, and transmission electron microscopy. A bioavailability study was performed in rats after oral administration of either STP-NEs, or commercial formulation (Diacomit^®). The resultant nanoemulsions were 146.6 nm in particle size with an entrapment efficiency of 99.47%. It was demonstrated that nanoemulsions significantly improved the biochemical stability and bioavailability of STP. The bioavailability of STP-NEs was up to 206.2% relative to Diacomit^®. Nanoemulsions fabricated from poly(ethylene glycol) monooleate/medium-chain triglycerides exhibited excellent performance in drug stabilization and absorption enhancement. The results suggest that STP-NEs are a promising means to solve the problems associated with stability and solubility of STP.

Keywords:

• stiripentol
• nanoemulsions
• stability
• intestinal permeability
• bioavailability

Acknowledgments

This work was supported by National Natural Science Foundation of China (81273532). The authors are thankful to the financial assistance from the Shandong Provincial Natural Science Foundation (ZR2011HQ028).

Disclosure

The authors report no conflicts of interest in this work.