Department of Chemistry, Université de Montréal, C.P. 6128 succursale Centre-Ville, Montréal, QC, H3C 3J7 Canada.
Langmuir. 2012 Sep 18;28(37):13431-40. doi: 10.1021/la303218q. Epub 2012 Sep 4.
Bile acids are amphiphilic endogenous steroids that act as anionic surfactants in the digestive tract and aggregate in aqueous solutions. Nonionic surfactants were synthesized by grafting poly(ethylene glycol) chains of various lengths (pegylation) to three bile acids (lithocholic, deoxycholic, and cholic acid) using anionic polymerization. The aggregation properties of the derivatives were studied with viscosity measurements and light scattering as well as with steady-state and time-resolved fluorescence techniques, and the aggregates were visualized by transmission electron microscopy to elucidate the effect of pegylation on the aggregation process. The fluorescence results showed a good correlation with the capacity of the bile acid derivatives to solubilize a hydrophobic drug molecule. The solubilization of ibuprofen depends on the length and the number of grafted PEG chains, and the solubilization efficiency increases with fewer PEG chains on the bile acid. The results indicate their potential for use in the design of new bile acid-based drug-delivery systems.
胆酸是具有两亲性的内源性甾体，在消化道中作为阴离子表面活性剂发挥作用，并在水溶液中聚集。通过阴离子聚合，将不同长度的聚乙二醇（PEG）链（PEG 化）接枝到三种胆酸（石胆酸、脱氧胆酸和胆酸）上，合成了非离子型表面活性剂。通过粘度测量、光散射以及稳态和时间分辨荧光技术研究了衍生物的聚集性质，并通过透射电子显微镜观察了聚集体，以阐明 PEG 化对聚集过程的影响。荧光结果与胆酸衍生物溶解疏水分子药物的能力有很好的相关性。布洛芬的溶解取决于 PEG 链的长度和数量，而胆酸上接枝的 PEG 链越少，溶解效率越高。结果表明它们有可能用于设计新的基于胆酸的药物传递系统。
