载香豆素6的PEG-PCL胶束跨MDCK极性上皮细胞的转运过程

Transcellular process of coumarin 6 loaded PEG-PCL micelles on MDCK epithelial cells

本课题对聚乙二醇聚ε-己内酯[poly(ethyl ethylene phosphate)-co-poly(ε-caprolactone),PEG-PCL]胶束跨犬肾极性上皮细胞(Madin-Darby Canine Kidney,MDCK)的转运过程进行了研究。采用薄膜水化法制备载香豆素6(coumarin 6,C6)的PEG-PCL胶束,并采用激光粒度测定仪测定其粒径,芘荧光探针法测定其临界胶束浓度(critical micelle concentration,CMC)。通过透射电镜、激光共聚焦扫描显微镜和荧光能量共振转移等方法研究了载C6的PEG-PCL胶束跨MDCK极性上皮细胞的转运过程。结果表明,PEG-PCL胶束的粒径约为30 nm,CMC为1.01μg·mL 1。PEG-PCL胶束以完整的形式被内吞进入细胞,经过细胞内转运过程将疏水性的模型药物C6从极性上皮细胞的基底侧排出,而PEG-PCL胶束本身很难以完整的形式跨膜。PEG-PCL胶束转运C6的过程是穿细胞途径,而非打开细胞紧密连接的细胞旁路途径。

The transcellular process of coumarin 6 （C6） loaded poly（ethyl ethylene phosphate）-co-poly （ε- caprolactone） （PEG-PCL） micelles on Madin-Darby Canine Kidney （MDCK） epithelial cells was investigated. C6 loaded PEG-PCL miceUes were prepared using the thin-film hydration method. The size of the micelles was characterized by dynamic light scattering analysis using a Malvern Zetasizer Nano ZS. The critical micelle concentration （CMC） was determined by pyrene fluorescence probe method. And the transcellular process of the micelles on MDCK epithelial cells was investigated by using transmission electron microscope, laser confocal scanning microscope and Forster resonance energy transfer technology. It turned out that the size ofPEG-PCL micelles was about 30 nm and CMC was 1.01 μg·mL^-1. PEG-PCL micelles were endocytosed in intact form and they could deliver hydrophobic drugs across the basolateral membrane of the epithelial cells. However, PEG-PCL is hardly being transported in micelle formation itself. The transportation of C6 by PEG-PCL micelles was through the transcellular pathway, yet not the paracellular pathway.