Korobko A V, Backendorf C, van der Maarel J R C
Leiden Institute of Chemistry, Leiden University, P. O. Box 9502, 2300 RA Leiden, The Netherlands.
J Phys Chem B. 2006 Aug 3;110(30):14550-6. doi: 10.1021/jp057363b.
We report the design and structural characterization of cationic diblock copolymer vesicles loaded with plasmid DNA based on a single emulsion technique. For this purpose, a DNA solution was emulsified in an organic solvent and stabilized by an amphiphilic diblock copolymer. The neutral block forms an interfacial brush, whereas the cationic attachment complexes with DNA. A subsequent change of the quality of the organic solvent results in the collapse of the brush and the formation of a capsule. The capsules are subsequently dispersed in aqueous medium to form vesicles and stabilized with an osmotic agent in the external phase. Inside the vesicles, the plasmid is compacted in a liquid-crystalline fashion as shown by the appearance of birefringent textures under crossed polarizers and the increase in fluorescence intensity of labeled DNA. The compaction efficiency and the size distribution of the vesicles were determined by light and electron microscopy, and the integrity of the DNA after encapsulation and subsequent release was confirmed by gel electrophoresis. We demonstrate reverse transfection of in vitro cultured HeLa cancer cells growing on plasmid-copolymer vesicles deposited on a glass substrate.
我们报道了基于单乳液技术的负载质粒DNA的阳离子双嵌段共聚物囊泡的设计与结构表征。为此，将DNA溶液在有机溶剂中乳化，并通过两亲性双嵌段共聚物使其稳定。中性嵌段形成界面刷，而阳离子部分与DNA形成复合物。随后有机溶剂性质的改变导致刷的塌陷并形成胶囊。这些胶囊随后分散在水介质中形成囊泡，并在外相中用渗透剂使其稳定。在囊泡内部，质粒以液晶方式压缩，如在正交偏振器下双折射纹理的出现以及标记DNA荧光强度的增加所示。通过光学和电子显微镜确定囊泡的压缩效率和尺寸分布，并通过凝胶电泳确认包封和随后释放后DNA的完整性。我们展示了在沉积于玻璃基板上的质粒 - 共聚物囊泡上生长的体外培养的HeLa癌细胞的反向转染。
