Sjöström B, Kaplun A, Talmon Y, Cabane B
Institute for Surface Chemistry, Stockholm, Sweden.
Pharm Res. 1995 Jan;12(1):39-48. doi: 10.1023/a:1016278302046.
Hydrophobic substances were dissolved in an organic solvent and emulsified with an aqueous solution at very high shear. Droplets of very small sizes (50-100 nm) were obtained by using surfactants which were combinations of lecithins and bile salts. After emulsification, the organic solvent was removed by evaporation, yielding stable dispersions of solid particles. The sizes, shapes, and structures of the particles were examined through quasi-elastic light scattering, small-angle neutron scattering and cryotransmission electron microscopy. Cholesterol acetate particles stabilized by lecithin and bile salts were found to be platelets of 10-20 nm thickness and 80 nm diameter. Cholesteryl acetate particles stabilized with POE-(20)-sorbitan monolaurate were dense spherical globules of diameter 100 nm. Particles with a composition similar to the endogenously occurring, lipoprotein, LDL, were large spherical globules studded with small vesicles. The subsequent evolution of the cholesteryl acetate dispersion upon aging was examined. There was no transfer of cholesteryl acetate between particles nor to large crystals. However, some aggregation of the particles was observed when the volume fraction of the particles in the aqueous dispersion exceeded 0.05. Thus, the structure of the nanoparticles obtained through deswelling of emulsion droplets changes according to the nature of the emulsifiers and to the composition of the hydrophobic substances which they contain.
疏水性物质溶解于有机溶剂中，并在极高剪切力下与水溶液乳化。通过使用卵磷脂和胆盐的组合作为表面活性剂，可得到非常小尺寸（50 - 100纳米）的液滴。乳化后，通过蒸发除去有机溶剂，得到固体颗粒的稳定分散体。通过准弹性光散射、小角中子散射和低温透射电子显微镜对颗粒的尺寸、形状和结构进行了检查。发现由卵磷脂和胆盐稳定的醋酸胆固醇颗粒是厚度为10 - 20纳米、直径为80纳米的血小板状颗粒。用聚氧乙烯（20）-脱水山梨醇单月桂酸酯稳定的醋酸胆甾醇颗粒是直径为100纳米的致密球形小球。具有与内源性脂蛋白低密度脂蛋白（LDL）相似组成的颗粒是布满小囊泡的大球形小球。研究了醋酸胆甾醇分散体老化后的后续演变。醋酸胆甾醇在颗粒之间或向大晶体之间没有转移。然而，当水分散体中颗粒的体积分数超过0.05时，观察到一些颗粒聚集。因此，通过乳液滴去溶胀获得的纳米颗粒的结构根据乳化剂的性质及其所含疏水性物质的组成而变化。
