Food protein-stabilized nanoemulsions as potential delivery systems for poorly water-soluble drugs: preparation, in vitro characterization, and pharmacokinetics in rats

Wei He¹, Yanan Tan¹, Zhiqiang Tian¹, Lingyun Chen², Fuqiang Hu³, Wei Wu^1
1Department of Pharmaceutics, School of Pharmacy, Fudan University, Shanghai, People's Republic of China; ²Department of Agricultural, Food and Nutritional Sciences, University of Alberta, Alberta, Canada; ³Department of Pharmaceutics, School of Pharmacy, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China

Abstract: Nanoemulsions stabilized by traditional emulsifiers raise toxicological concerns for long-term treatment. The present work investigates the potential of food proteins as safer stabilizers for nanoemulsions to deliver hydrophobic drugs. Nanoemulsions stabilized by food proteins (soybean protein isolate, whey protein isolate, ß-lactoglobulin) were prepared by high-pressure homogenization. The toxicity of the nanoemulsions was tested in Caco-2 cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium-bromide viability assay. In vivo absorption in rats was also evaluated. Food protein-stabilized nanoemulsions, with small particle size and good size distribution, exhibited better stability and biocompatibility compared with nanoemulsions stabilized by traditional emulsifiers. Moreover, ß-lactoglobulin had a better emulsifying capacity and biocompatibility than the other two food proteins. The pancreatic degradation of the proteins accelerated drug release. It is concluded that an oil/water nanoemulsion system with good biocompatibility can be prepared by using food proteins as emulsifiers, allowing better and more rapid absorption of lipophilic drugs.

Keywords: oil in water nanoemulsions, food proteins, poorly water-soluble drugs, biocompatibility, in vivo absorption