Department of Chemical & Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118, USA.
Langmuir. 2010 Mar 2;26(5):3225-31. doi: 10.1021/la9032157.
Tubular liposomes containing a hydrophilic model compound (fluorescein sodium salt, FSS) were entrapped inside the internal aqueous phase (W(1)) of water-in-oil-in-water (W(1)/O/W(2)) double-emulsion globules. Our hypothesis was that the oil membrane of double emulsions can function as a layer of protection to liposomes and their contents and thus better control their release. Liposomes were prepared in bulk, and their release was observed microscopically from individual double-emulsion globules. The liposomes containing FSS were released through external coalescence, and the behavior of this system was monitored visually by capillary video microscopy. Double-emulsion globules were stabilized with Tween 80 as the water-soluble surfactant, with Span 80 as the oil-soluble surfactant, while the oil phase (O) was n-hexadecane. The lipids in the tubular liposomes consist of L-alpha-phosphatidylcholine and Ceramide-VI. Variations of Tween 80 concentration in the external aqueous phase (W(2)) and Span 80 concentration in the O phase controlled the release of liposomes from the W(1) phase to the W(2) phase. The major finding of this work is that the sheer presence of liposomes in the W(1) phase is by itself a stabilizing factor for double-emulsion globules.
管状脂质体内部水相（W(1)）中包裹了亲水性模型化合物（荧光素钠盐，FSS）。我们的假设是，双乳液的油膜可以作为脂质体及其内容物的保护层，从而更好地控制它们的释放。脂质体是批量制备的，从单个双乳液滴中观察到它们的释放。含有 FSS 的脂质体通过外部聚结释放，通过毛细管视频显微镜可以直观地监测该体系的行为。双乳液滴由 Tween 80 稳定，Tween 80 是水溶性表面活性剂，Span 80 是油溶性表面活性剂，油相（O）是正十六烷。管状脂质体中的脂质由 L-α-磷脂酰胆碱和神经酰胺-VI 组成。外部水相（W(2)）中 Tween 80 浓度和 O 相中的 Span 80 浓度的变化控制着脂质体从 W(1)相到 W(2)相的释放。这项工作的主要发现是，W(1)相中脂质体的存在本身就是双乳液滴的稳定因素。
